| effect of magnesium deficiency on erythrocyte aging in rats. | rats placed on a magnesium-deficient diet show decreased erythrocyte magnesium concentration, shortened erythrocyte survival, and erythrocyte membrane ultrastructure defects and become progressively anemic. whether these pathologic processes are due to abnormal erythropoiesis or occur in the peripheral circulation is unknown. in the present study, magnesium and hemoglobin concentrations, reticulocyte count, erythrocyte pyrophosphatase, and pyruvate kinase activities were determined at weekly int ... | 1980 | 6106388 |
| enzymatic and ultrastructural study of lysosomes in rats bearing radiation-induced thyroid follicular carcinoma. | radiation-induced well-differentiated and poorly differentiated follicular thyroid cancers were transplanted into the intrascapular fat pads of male fisher 144 rats. the tumors grew in the recipient rats and after a time interval were removed and studied along with normal rat thyroids for lysosomal activity and ultrastructural characteristics. plasma from experimental and control rats was also studied for lysosomal activity. rats with radiation-induced thyroid carcinoma had a decrease in growth ... | 1981 | 6109795 |
| propagation of korean hemorrhagic fever virus in laboratory rats. | korean hemorrhagic fever virus (khfv) has been adapted to the wistar and fisher strains of rats. infection was detected by the appearance of specific antigen in the lung tissue of the infected rats at 14 to 64 days after inoculation and by the appearance of circulating antibodies in ther serum which reacted specifically with khfv antigen in the lungs of infected apodemus agrarius subsp. coreae 3 weeks after inoculation. distribution of antigen in rat tissues as determined by immunofluorescent st ... | 1981 | 6111538 |
| age-related changes in dopamine, lhrh and somatostatin in the rat hypothalamus. | the distribution of dopamine, somatostatin and lhrh was examined in young and aged male rats of the fisher 344 strain. dopamine histofluorescence and peptide immunocytochemical staining were performed together in each animal by the use of a stimultaneous visualization technique. comparative analysis or rats at 3, 12, 20, and 30 months of age revealed a general decrease in somatostatin and lhrh in the median eminence; dopamine fluorescence intensity also was depressed in the median eminence altho ... | 1980 | 6115324 |
| histochemistry of nadh diaphorase and gamma-glutamyltranspeptidase in rat bladder tumors. | to improve identification of preneoplastic bladder cancer cells, we have studied two enzyme histochemical changes in bladder tumors induced in male fisher 344 rats by the carcinogen n-butyl-n-(4-hydroxybutyl)-nitrosamine. in early areas of focal nodular hyperplasia there was a dramatic increase in staining for nadh:menadione oxidoreductase (diaphorase)activity. in nonfocal areas as well, there were many individual cells with intense staining, while the controls were of uniform moderate staining. ... | 1982 | 6124324 |
| diazepam disposition in mature and aged rabbits and rats. | the disposition of diazepam after intravenous administration was investigated in mature young and old female dutch belted rabbits (1-1.5 and 5.6.5 years) and fischer-344 rats (6 and 30 months) to determine whether they exhibited an age-related increase in distribution similar to that previously observed in the human. no significant differences were found in the pharmacokinetic behavior of diazepam or its n,-demethylated metabolite between the young and old rabbits, although there was a suggestio ... | 1982 | 6126343 |
| a 174-kilodalton atpase/datpase polypeptide and a glycoprotein of apparently identical molecular weight are common but distinct components of higher eukaryotic nuclear structural protein subfractions. | a 174-kilodalton polypeptide of the drosophila nuclear matrix-pore complex-lamina fraction has been identified as an atpase/datpase on the basis of direct uv photoaffinity labeling studies; a polypeptide with similar properties has been found in nuclear envelope fractions prepared from several vertebrate sources (berrios, m., blobel, g., and fisher, p. a. (1983) j. biol. chem. 258, 4548-4555). this atpase/datpase polypeptide co-migrates on sodium dodecyl sulfate (sds)-polyacrylamide gels with a ... | 1983 | 6138358 |
| effects of cimetidine and ranitidine on halothane metabolism and hepatotoxicity in an animal model. | this study was undertaken to determine the effects of two h2-receptor antagonists, cimetidine and ranitidine, on halothane metabolism and hepatotoxicity in the hypoxic fisher 344 rat model for halothane hepatitis. in this model, liver injury is caused by toxic intermediates formed during metabolism of halothane by a reductive pathway. administration of cimetidine (120 mg/kg ip) 20 min prior to anesthesia led to inhibition of the reductive pathway, as assessed by measurement of the exhaled metabo ... | 1984 | 6141900 |
| age-dependent alterations in synaptic membrane systems for ca2+ regulation. | the effects of aging on two neuronal plasma membrane ca2+ regulating systems have been examined using synaptic membranes isolated from the brains of adult (5-7-month-old) and aged (23-25-month-old) fisher 344 rats. the kinetic characteristics of the na+-dependent ca2+ transport system were found to be altered in the aged animals. the affinity of the transport carrier for ca2+ was decreased in membranes from aged animals, with very little change in the maximal transport capacity of the system. th ... | 1984 | 6144821 |
| effect of acetaminophen toxicity on erythrocyte osmotic fragility in the fisher rat. | the protective effect of propylthiouracil (ptu) pretreatment against acetaminophen-induced erythrocyte osmotic fragility was determined in the male fisher rat. hepatotoxicity was assessed for comparative purposes. ptu (0.15%) was fed in chow for a period of 12 days. acetaminophen (1 g/kg body wt) was then administered orally by a stomach tube after an overnight fast. the rats were killed either 4 or 24 hr later. erythrocyte osmotic fragility was determined by the extent of hemolysis in various c ... | 1984 | 6149873 |
| control of growth of estrogen-sensitive cells: role for alpha-fetoprotein. | the role played by alpha-fetoprotein (afp) during the perinatal period in rats has not yet been ascertained despite earlier suggestions that this plasma protein affected the multiplication, in an "in animal-in culture" system of tumor cells that are stimulated by estrogen (e) for growth. to test this inference developed from our previous work, afp was purified by reverse affinity chromatography to homogeneity by electrophoretic and immunochemical criteria. purified afp was added at different con ... | 1980 | 6154944 |
| collagen lysyl oxidase activity in the lung increases during bleomycin-induced lung fibrosis. | intratracheal administration of bleomycin caused pulmonary fibrosis in rats. bleomycin sulfate (640 micro grams/165 g b.wt. in 0.5 ml of sterile saline) was instilled intratracheally into male fisher 344 rats (169 +/- 5 g), whereas control animals received 0.5 ml of sterile saline by the same route. one, 3, 7, 14, 28 and 322 days after instillation, the animals were killed, the lungs were homogenized in 6 m urea, 0.01 m nacl, 0.001 m potassium phosphate (ph 8.3) and the homogenates were subjecte ... | 1981 | 6170751 |
| [cell-free pseudomonas vaccine. iii. immunochemical analysis of purified pseudomonas aeruginosa protein antigens and protective properties of antisera against these antigens]. | the immunochemical analysis of isolated and purified antigens a and b obtained from p. aeruginosa, strains 868 (serogroup o3 according to lányi or immunotype 3/7 according to fisher) and 170015 (serogroup o7 or immunotype 2), was carried out. rabbit antisera to proteins a and b, as well as to the initial aqueous extracts and partially purified aqueous extracts, were obtained. cross activity between the protein antigens of different strains was established by the methods of immunodiffusion and tw ... | 1983 | 6188300 |
| repeated pulmonary function evaluation following bleomycin treatment. | a computerized, nonsurgical, pulmonary function measurement method was tested for sensitivity and utility in detecting the development of fibrosis. bleomycin, a fibrogenic agent, was intratracheally instilled into male fisher 344 rats. respiratory function was monitored in restrained, awake animals before treatment and for the subsequent 4 wk. in the first week, among responders, a significant (p less than 0.05) drop in body weight, tidal volume, and compliance was accompanied by a significant i ... | 1983 | 6188851 |
| cytokeratin and nonhistone protein antigenic changes in rat liver during azo dye but not hepatotoxin feeding. | chromosomal proteins from rat liver have been assessed immunologically for changes in specific cytokeratins or primary tumor nonhistone proteins during treatment with an azo dye hepatocarcinogen (3'-methyl-4-dimethylaminoazobenzene), (3'-me-dab) or the hepatotoxin alpha-naphthyl-iso-thiocyanate (alpha-nit). fisher rats were fed laboratory diets supplemented with either agent and sacrificed sequentially at various intervals. chromosomal proteins from these livers were electrophoresed in the prese ... | 1983 | 6190586 |
| abnormal phagolysosome fusion in pulmonary alveolar macrophages of rats exposed chronically to cigarette smoke. | cigarette smoking is strongly associated with functional and morphologic changes in pulmonary alveolar macrophages (pam). phagocytic activity is a primary function of pam, and although the ingestion of particles appears to be normal in the pam of cigarette smokers, published data suggest that antimicrobial activity of these cells might be diminished. because phagolysosome fusion (plf) is an important aspect of the phagocytic process subsequent to the ingestion phase, plf was evaluated in pam lav ... | 1984 | 6206755 |
| susceptibility to adjuvant arthritis in da and f344 rats. a dominant trait controlled by an autosomal gene locus linked to the major histocompatibility complex. | the hereditary of adjuvant-induced arthritis in rats of the da and fisher 344 strains was examined. development of arthritic lesions in response to a single injection of supplemented freund's complete adjuvant has been found to be controlled by an autosomal, dominant gene locus, ar. the capacity to respond was present in da rats and absent in our fisher rats. ar has been found to be linked to the major histocompatibility complex genes with which it exhibits a high rate of recombination. | 1982 | 6215923 |
| induction of prostaglandin synthesis-dependent suppressor cells with endotoxin: occurrence in patients with thermal injuries. | the induction of lymphocyte suppressor activity with bacterial endotoxin is well documented. while most of the evidence has been obtained using animal models and has required large doses of endotoxin, we have demonstrated that additions of as little as 1.0 ng of chromatographically purified endotoxin [from escherichia coli 055:b5, e. coli 0111:b4, pseudomonas aeruginosa (fisher-devlin immunotype 1), serratia marcescens, or salmonella minnesota] to human mixed lymphocyte or to mitogen-stimulated ... | 1983 | 6222063 |
| imino proton assignments in the proton nuclear magnetic resonance spectrum of the lambda phage or3 deoxyribonucleic acid fragment. | the 17 base pair duplex d(tatcaccgcaagggatap) . d(tatcccttgcggtgatap) corresponding to the or3 operator site of lambda phage has been synthesized and studied by 1h nuclear magnetic resonance spectroscopy at 470 mhz. the 13 imino proton resonances observed at 20 degrees c have been assigned to specific base pairs at positions 3-15 on the basis of nuclear overhauser effect measurements and studies of the temperature dependence of peak intensities. resonances from the a-t base pairs at positions 1, ... | 1983 | 6226312 |
| pontine hemorrhage causing fisher one-and-a-half syndrome with facial paralysis. | the case of a 58-year-old white man with a history of high blood pressure and chronic obstructive pulmonary disease who developed double vision followed by right-sided facial paralysis is reported. a computerized axial tomogram (ct) scan showed an enhancing lesion in the pontine tegmentum, and the diagnoses of pontine glioma or hemorrhage were considered. physical findings were limited to the cranial nerves. conservative management with decadron for 3 weeks resulted in a prompt clinical improvem ... | 1982 | 6226696 |
| dracunculus insignis in fishers in new hampshire. | | 1984 | 6239848 |
| cyclic nucleotides and platelet aggregation in hypertensive rats with ectopic pituitary tumor. | the transplantable pituitary tumor mtt-f4 secretes several pituitary hormones in fisher rats, resulting in severe cardiovascular disease with a mineralocorticoid type of hypertension and hyperlipidemia. the mineralocorticoid-dependent hypertension possesses particular characteristics in humans and animals. it was of interest to study cyclic nucleotides and platelet aggregation in the fisher rat with an mtt-f4 tumor in order to evaluate the type of abnormalities in this form of hypertension. the ... | 1980 | 6249246 |
| distinct transformation phenotypes induced by polyoma virus and simian virus 40 in rat fibroblasts and their control by an early viral gene function. | several transformed cell lines established from fisher rat cells (fr 3t3) infected with wild-type polyoma virus or simian virus 40 or early temperature-sensitive mutants (polyoma tsa and simian virus 40 tsa30) were studied for their transformation phenotypes. the distinct patterns which were obtained for polyoma and simian virus 40 transformants led to the conclusion that these two viruses express different transforming abilities in rat cells. the results obtained with temperature-sensitive muta ... | 1980 | 6251242 |
| integration of the simian virus 40 genome into cellular dna in temperature-sensitive (n) and temperature-insensitive (a) transformants of 3t3 rat and chinese hamster lung cells. | we studied the pattern of integration of the simian virus 40 (sv40) genome into the cellular dna of n-transformants (temperature sensitive) and a-transformants (temperature insensitive) derived from 3t3-fisher rat and chinese hamster lung cells. the sv40 dna was covalently linked to the cellular dna in both types of transformants. in the rat cells, most n-transformants contained sv40 sequences integrated at a single site; most a-transformants contained sv40 sequences integrated at two to five si ... | 1980 | 6251267 |
| aerosol stability and respiratory infectivity of japanese b encephalitis virus. | experiments were conducted to examine the aerosol stability and respiratory infectivity of japanese b encephalitis virus. at 75 degrees f (about 24 degrees c), survival of the virus as aerosol was inversely related to relative humidity. after correction for physical decay, the mean virus half-lives of the virus were 28, 38, and 62 min at relative humiditis of 80, 55, and 30%, respectively. virus recoveries as aerosol at 4 min aftr dissemination generally exceeded the theoretical limit of 100%, b ... | 1980 | 6254888 |
| monoclonal antibodies against antigens displayed on a progressively growing mammary tumor. | we have produced lymphocyte hybridomas between mouse myeloma cells and either spleen cells of c3h/f/c57bl/6 mice bearing the mm5mt/c1 tumor-producing murine mammary tumor virus (mmtv) or spleen cells from fisher rats inoculated with the same tumor. two classes of hybridoma-secreted monoclonal antibodies were obtained. in the first class are ivc11, iiia1, and ve7, each of which precipitated a 52,000-dalton protein from 125i-labeled purified preparations of mmtv and [3h]glucosamine-labeled mm5mt/c ... | 1981 | 6264447 |
| transformation of rat cells by an altered polyoma virus genome expressing only the middle-t protein. | a modified polyoma virus genome has been constructed which can encode the middle-t protein, but not the large-t or small-t proteins. this was achieved, starting with the full length viral dna inserted into a plasmid vector, by replacing a small genomic restriction fragment spanning the middle-t intervening sequence with the equivalent fragment from a cloned partial cdna copy of the middle-t protein mrna. transfection of the modified viral dna into cultured rat cells efficiently induced the forma ... | 1981 | 6265803 |
| isoproterenol responsiveness and myocardial beta-adrenergic receptors in young and old rats. | to elucidate the association of beta-adrenergic receptors with decreased myocardial catecholamine responsiveness in aging, we investigated the chronotropic response to isoproterenol and myocardial beta-adrenergic receptors in fisher 344 rats of 3, 12, and 24 months of age. heart rate response to isoproterenol (50 mug/kg, subcutaneously) was greatest in 3-month-old animals, both in maximum heart rate achieved and increment over baseline. twelve-month-old animals had significantly lower maximal he ... | 1982 | 6276461 |
| reversal of diabetes by the isotransplantation of nicotinamide-streptozotocin-induced islet adenoma in rats. | the effect of syngeneic transplantation of islet tumors induced by streptozotocin-nicotinamide treatment into fisher inbred diabetic rats was studied. transplantation of 10 mg of tumor tissue under the kidney capsule of severely diabetic animals resulted in complete amelioration in 9 of 14 animals. partial improvement was noted in three animals, whereas only one animal showed no change in diabetic condition within 4 months. improvement in diabetes was accompanied by gain in body weight, decrease ... | 1982 | 6277054 |
| metabolism of acetaminophen by the isolated perfused kidney. | acetaminophen (apap) produces proximal tubular necrosis in the fisher 344 rat. this lesion may result from the covalent binding of reactive intermediates of apap to cellular macromolecules when glutathione (gsh) is sufficiently depleted. experiments were designed to evaluate the ability of the kidney to convert apap to reactive electrophilic metabolites capable of depleting renal gsh by quantifying gsh concentrations in isolated perfused kidneys perfused with apap. perfusion without apap reduced ... | 1982 | 6278138 |
| aging and benzodiazepine binding in the rat cerebral cortex. | the specific binding of 3h-diazepam in the cerebral cortex was investigated in membrane preparations from 6 and 30 month old fisher-344 rats. no age-related differences in the association, equilibrium, or dissociation, binding characteristics were observed. the increased sensitivity of the elderly to the central sedative effects of the benzodiazepines does not, therefore, appear to involve changes in binding to the receptor site located in the cortex. | 1982 | 6280005 |
| retinoic acid binding protein in normal and neopolastic rat prostate. | sucrose density gradient analysis of cytosol from normal and neoplastic rat prostatic tissues exhibited a peak of (3h) retinoic acid binding in the 2s region, corresponding to the cytoplasmic retinoic acid binding protein (crabp). in the fisher-copenhagen f1 rat, crabp was present in the lateral lobe, but could not be detected in the ventral nor in the dorsal prostatic lobes. four sublines of the r-3327 rat prostatic tumor contained similar levels of this binding protein. the absence of crabp in ... | 1982 | 6283503 |
| bacteriophage lambda dna packaging: scanning for the terminal cohesive end site during packaging. | bacteriophage lambda packages the dna of the related phage 21 poorly [hohn, b. (1975) j. mol. biol. 98, 93--106]. to understand the nature of the packaging defect, the interaction of the cohesive end site (cos) specific for phage 21 (cos phi 21) with phage lambda terminase has been investigated. the ability of lambda terminase to cleave cos phi 21 was studied in vitro; lambda terminase cleaved cos phi 21 only 1% as well as it cleaved the phage lambda cohesive end site (cos lambda). in vitro pack ... | 1982 | 6285351 |
| a physiological and morphological study of the horizontal cell types of the rabbit retina. | a perfused, isolated retina-eyecup preparation of the rabbit was utilized to correlate the physiology and morphology of horizontal cells. neurons were physiologically characterized by intracellular recording techniques and subsequently stained with intracellular iontophoretically injected horseradish peroxidase for morphological identification. three types of rabbit horizontal cell recordings have been differentiated, based on variations in response waveform, amplitude-intensity properties, and ... | 1982 | 6288777 |
| perchloric acid-soluble serum glycoprotein as an index for tumor cell burden in the early detection of cancer. | neoplastic cells, particularly human mammary carcinoma cells, shed or secrete glycoproteins which are tumor-specific. these compounds contain n-acetylneuraminic acid (nana) and they differ from the bulk of serum proteins and glycoproteins in being soluble in perchloric acid. graded number of r3230 adenocarcinoma (adca) cells were implanted subcutaneously in groups of female fisher rats. at time intervals, while under anesthesia the spleens were dissected out, and blood was drawn from the animals ... | 1982 | 6290061 |
| deletions of n-terminal sequences of polyoma virus t-antigens reduce but do not abolish transformation of rat fibroblasts. | polyoma virus transforms, upon infection or dna transfection, nonpermissive fisher rat fibroblasts. cloned viral dna was deleted of sequences around the bg/i site at nucleotide 86 by bal31 nuclease treatment and then recloned in escherichia coli. the extent of deletion for each mutant was then determined by dna sequencing. deletions included the early transcription control signals; others stretched into the n-terminal coding sequences of the viral tumor antigens. the transformation efficiency of ... | 1982 | 6294500 |
| characterization of tumor-specific transplantation antigen induced in cells infected or transformed by polyomavirus. | tumor-specific transplantation antigen (tsta) activity was investigated (with the use of inbred balb/c and c3h mice and inbred fisher and wistar rats) in various early polyomavirus (py)-coded proteins by three methodologies: 1) immunoprecipitation by anti-t-antigen sera, gel slicing, and immunization; 2) affinity chromatography with the use of anti-tumor-associated antigen serum; and 3) use of a py mutant, ng18. the results obtained by all three techniques allowed refutation of the hypothesis th ... | 1983 | 6296521 |
| similar transforming growth factors (tgfs) produced by cells transformed by different isolates of feline sarcoma virus. | fisher rat embryo cells transformed by each of three independent isolates of feline sarcoma virus (fesv) are shown to release transforming growth factors (tgfs) into cell culture medium. these acid- and heat-stable peptides compete for binding to, and stimulate phosphorylation of, egf membrane receptors and promote anchorage-independent cell growth. cells transformed by the gardner and synder-theilen strains of fesv produce high titers of tgf (60-200 ng eq egf/liter) while cells transformed by m ... | 1983 | 6297155 |
| urinary cyclic amp and cyclic gmp in rats given three different concentrations of cadmium in the diet for one year. | male and female weanling rats of the spf fisher strain were fed purified diets containing three different levels of cadmium (0.008, 0.3, 30 micrograms cd/g feed). urine was collected from each animal 1 year after the start of the experiment, and cyclic amp and cyclic amp in the urine were measured by radioimmunoassay. urinary excretion of cyclic amp and gmp changed in proportion to the intake of cd. the ratio of cyclic amp: cyclic gmp, which combined the changes of these two cyclic nucleotides, ... | 1983 | 6301107 |
| isolation of v-fms and its human cellular homolog. | the integrated form of mcdonough fesv proviral dna, including cellular flanking sequences, was molecularly cloned from nonproductively transformed fisher rat cells. acquired cellular-derived (v-fms) sequences within the cloned proviral dna were mapped from between 2.6 and 5.5 kb from the 5'ltr. upon transfection, the cloned proviral dna was biologically active; it caused induction of the transformed phenotype and the resulting transformed cells expressed the major mcdonough fesv translational pr ... | 1983 | 6302985 |
| comparative studies of the expression of linked escherichia coli gpt gene and bpv-1 dnas in transfected cells. | a series of hybrid plasmids, containing two selective markers that can be expressed in mammalian cells have been constructed. these plasmids are derived from the psv2gpt recombinant plasmid described by mulligan and berg (1980) and contain the entire bpv-1 dna, or the hindiii-bamhi large transforming fragment (t69) or the early transforming region of polyoma virus dna. dna transfers into fisher rat 3t3 cells were performed either by the calcium phosphate coprecipitation technique, or by protopla ... | 1983 | 6306916 |
| transforming growth factors produced by retrovirus-transformed rodent fibroblasts and human melanoma cells: amino acid sequence homology with epidermal growth factor. | transforming growth factors (tgfs) were purified from serum-free medium conditioned by retrovirus-transformed fisher rat embryo fibroblasts, mouse 3t3 cells, and two human melanoma cell lines. the purification of each tgf was monitored in a radioreceptor assay based on receptor crossreactivity with mouse submaxillary gland epidermal growth factor (megf) and was achieved by gel permeation chromatography of the acid-soluble tgf-containing activity, followed by reverse-phase high-pressure liquid ch ... | 1983 | 6308641 |
| an analysis of transformed clones obtained by coinfections with hr-t and ts-a mutants of polyoma virus. | clones of stably transformed rat cells from the f-111 (fisher rat embryo) and nrk (normal rat kidney) cell lines have been obtained by complementation using pairs of nontransforming polyoma mutants of the hr-t and ts-a classes. a total of 78 clones were isolated and studied, 21 from the nrk line, and 57 from the f-111 line. these "complementation transformed clones" were then examined for the presence and expression of each of the parental mutant viruses. the expression of viral t (tumor) antige ... | 1983 | 6314651 |
| class i antibody induction by rat endothelium. | supradiaphragmatic vein grafts were transplanted from aci (rt1a) to fisher (rt1(1)) rats to determine whether the endothelium and/or circulating passenger leukocytes were necessary for the induction of an antibody response. vein grafts from immunosuppressed and irradiated donors induced lymphocytotoxic and hemagglutinating antibody in recipient rats. in addition, igg antibody produced in fisher recipients was found by indirect immunofluorescence to donor endothelium. when the endothelium was rem ... | 1984 | 6323854 |
| evaluation of the toxic effects of aflatoxin b1 with a taste aversion paradigm in rats. | a taste aversion test was used to evaluate the toxic effects of aflatoxin (af) b1 which is considered to be one of the most potent hepatocarcinogens known. sixty male fisher rats were randomly assigned to six treatment (injection) groups: water (h2o); dimethyl sulphoxide (dmso); lithium chloride (licl); 0.125 mg/kg afb1 (af-low); 0.250 mg/kg afb1 (af-medium) and 0.500 mg/kg afb1 (af-high). after adaption to a water-deprivation schedule which permitted 10-min access to water each day, the rats we ... | 1984 | 6325970 |
| cell lines derived from tumors induced in syngeneic rats by fr 3t3 sv40 transformants no longer synthesize the early viral proteins. | several sv40-transformed fr 3t3 rat cell lines formed tumors upon inoculation to syngeneic immunocompetent fisher rats. these tumors, which appeared only after a long latency period, showed a fast rate of growth. tumor-derived (td) cell lines were established in culture from several tumors induced by independent transformants, and their properties were analyzed. though td cells were highly tumorigenic, their level of transformation in culture was similar to that of the original transformants. th ... | 1984 | 6328754 |
| the influence of pituitary hormones on adjuvant arthritis. | adjuvant arthritis was induced in female fisher rats by injecting their right hind paw with 0.1 ml freund's complete adjuvant. the development of adjuvant arthritis was inhibited by hypophysectomy and by daily treatment of intact animals with the dopaminergic agent bromocriptine. adjuvant arthritis developed normally if hypophysectomized or bromocriptine-suppressed animals were treated with either prolactin or growth hormone. additional treatment with adrenocorticotropic hormone inhibited this r ... | 1984 | 6329236 |
| the effects of prolactin on rat ovarian function. | hyperprolactinemia has been associated with several reproductive disorders. to investigate whether hyperprolactinemia directly affects rat ovarian function, we examined the ovarian histopathology and the activities of the four ovarian enzymes 3 beta-hydroxysteroid dehydrogenase (3 beta-hsd), 17-hydroxylase (17-oh), 17,20-desmolase (17,20-d) and aromatase in hyperprolactinemic rats and controls. hypophysectomized, gonadotropin-treated fisher rats were made hyperprolactinemic by isografting pituit ... | 1984 | 6335928 |
| prophylactic metronidazole in appendectomy: a double-blind controlled trial. | ninety-eight patients with suspected nonperforated acute appendicitis have to date been entered into a continuing, prospective, blinded randomized trial to determine the role of prophylactic metronidazole in postoperative wound infection. twenty-six patients were excluded for the following reasons: diagnosis other than acute appendicitis (16), perforation of the appendix (8), administration of other antibiotics (1), and refusal to enter study (1). seventy-two patients, 47 men and 25 women, with ... | 1983 | 6336864 |
| effects of intrasplenic injection of hepatocytes, hepatocyte fragments and hepatocyte culture supernatants on d-galactosamine-induced liver failure in rats. | intraperitoneal injection of 0.5 g/kg d-galactosamine results in 95% lethal acute acute liver failure in male fisher 344 rats. intrasplenic injection of viable syngeneic hepatocytes 20-28 h after poisoning improves survival in a dose-dependent fashion, 10(7) cells being the optimal dose with a survival rate of 47.1%. while nonviable cells and hepatocyte fragments are totally ineffective, 42.9% of rats survive after injection of 28-hour liver cell culture supernatant. it is concluded that soluble ... | 1983 | 6345168 |
| hepatocellular transplantation in rats with toxic induced liver failure: results of iso-, allo- and xenografts. | intrasplenic hepatocytes transplantation was carried out in wistar-lewis strain inbred rats, after inducing acute hepatic failure by intravenous injection of dimethylnitrosamine (dmna) (30 mg/kg). iso-, allo-(cdf-fisher strain) and xenogeneic (new zealand white rabbit) grafts were performed. liver cells suspension was obtained by mechanical separation. the results demonstrated the efficacy of iso- and allotransplants, but not of xenogeneic hepatocytes, in improving significantly the survival rat ... | 1983 | 6347966 |
| treatment of occult bacteremia: a prospective randomized clinical trial. | antibiotic therapy for children without foci of infection and at risk for bacteremia is controversial. a prospective randomized clinical trial was conducted using expectant antibiotic therapy in children at risk for bacteremia. a total of 96 children (aged 6 to 24 months) with temperature of more than 40 degrees c, no identifiable source of infection, and a leukocyte count greater than or equal to 15,000/microl and/or sedimentation rate greater than or equal to 30 were enrolled. the following te ... | 1983 | 6356004 |
| cutaneous inflammatory reactions to group a streptococcal cell wall fragments in fisher and lewis inbred rats. | systemic administration of an aqueous suspension of group a streptococcal cell wall fragments induces severe, chronic erosive polyarthritis in lew/n female rats, but rarely in f344/n female rats. in the present study, we attempted to exclude unresponsiveness to the cell walls as a mechanism for arthritis resistance in f344/n females. cutaneous inflammatory reactions were assessed in both strains at various time points after direct injection of cell wall fragments of three different average molec ... | 1983 | 6358033 |
| selective lymphoid irradiation and cyclosporin a in rat heart allografts. | short-term peritransplant treatment utilizing 2-dose alg and 1-dose palladium-109-hematoporphyrin (pd-h) for selective lymphoid irradiation (sli) leads to donor-specific permanent acceptance of heart allografts in the fisher to lewis rat model. the same treatment significantly prolongs survival of hearts transplanted to strongly histoincompatable , presensitized, and xenogeneic recipients. the purpose of this study was to evaluate synergistic effects of short-term, low-dose cyclosporin treatment ... | 1984 | 6374286 |
| the effect of perioperative adriamycin on skin-graft take and adherence in the rat. | this two-part study was undertaken to evaluate the effect of perioperative adriamycin on skin-graft take and adherence in an animal model. thirty-four male fisher rats were divided into control and experimental groups. the controls received intravenous saline, and the experimental animals received adriamycin 6 mg/kg (ld 10) 24 hours preoperatively. each animal was then grafted with an autogenous split-thickness skin graft on a contiguous dermal and fascial bed. skin-graft take was judged and mea ... | 1984 | 6382370 |
| in vitro response of human t cells to pseudomonas aeruginosa. | pseudomonas aeruginosa is a gram-negative bacillus that is a major cause of morbidity and mortality in immunosuppressed patients, burn patients, and patients with cystic fibrosis. although immunity to these bacteria has been associated with serum antibody, more recent evidence suggests that t-cell-mediated immunity may also be important. to evaluate human t-cell responsiveness to these bacteria, the optimal conditions were determined for in vitro proliferation of human peripheral blood lymphocyt ... | 1983 | 6404830 |
| anti-pseudomonas aeruginosa activity of an intravenous human igg preparation in burned mice. | a commercially available human igg chemically modified for intravenous infusion (igiv) was tested in burned mice for activity against eight strains of pseudomonas aeruginosa. an 8.7 to 9.6% full-thickness burn was made with a gas flame on the shaved backs of anesthetized mice. a suspension of p. aeruginosa in 0.5 ml saline was then injected subcutaneously in the burn site. inocula included seven american type culture collection reference strains representing the seven fisher-devlin-gnabasik immu ... | 1983 | 6408266 |
| pseudomonas aeruginosa isolates from patients with cystic fibrosis: a class of serum-sensitive, nontypable strains deficient in lipopolysaccharide o side chains. | twenty-six pseudomonas aeruginosa strains from patients with cystic fibrosis were typed by the fisher immunotyping scheme. only 6 strains were agglutinated by a single typing serum, whereas 15 strains were agglutinated with more than one serum and 5 were not agglutinated by any serum. neither the polyagglutinable nor the nonagglutinable strains were typable by hemagglutination inhibition or immunodiffusion, suggesting that these polyagglutinable strains did not express multiple serotype antigens ... | 1983 | 6413410 |
| immunologic basis for mouse protection provided by high-molecular-weight polysaccharide from immunotype 1 pseudomonas aeruginosa. | antibody responses were assayed in inbred strains of mice immunized with a high-molecular-weight polysaccharide (it-1 ps) isolated from fisher immunotype 1 pseudomonas aeruginosa (p. aeruginosa 1). c3h/anf mice generated the greatest antibody response after immunization with 1 microgram of antigen and could then survive challenge with 5 ld100 of p. aeruginosa 1 organisms. balb/c mice produced lower levels of antibody and did so only after immunization with 50 micrograms of it-1 ps. these mice co ... | 1983 | 6419317 |
| toxicity of aflatoxin b1 in rat and mouse hepatocytes in vivo and in vitro. | the reported ld50 for the adult, male fisher rat is 1.2 mg aflatoxin b1/kg body weight (i.p.); we have found that male c57bl/6 mice survive single doses of aflatoxin b1 as high as 60 mg/kg (i.p.). we have demonstrated a 1000-fold greater lc50 of aflatoxin b1 for primary mouse liver cell cultures from c57bl/6 male mice (3 x 10(-5) m) than for primary liver cells from f344 male rats (3 x 10(-8) m). in 4 h of exposure to a non-toxic dose (1 x 10(-9) m) of [3h]aflatoxin b1, cultured rat liver cells ... | 1984 | 6424269 |
| comparative anti-pseudomonas aeruginosa activity of chemically modified and native immunoglobulin g (human), and potentiation of antibiotic protection against pseudomonas aeruginosa and group b streptococcus in vivo. | immunoglobulin g intravenous is prepared by controlled reduction and alkylation of approximately four interheavy chain disulfide bonds per molecule. to determine if the protective activity of antibody modified by this process is diminished, mice were treated with identical doses of reduced and alkylated igg and native igg prepared from the same plasma pool. three hours later mice were given a 10 percent body surface burn followed by challenge with the seven fisher-devlin-gnabasik immunotypes of ... | 1984 | 6424444 |
| effects of adrenergic agents, vasopressin and ionophore a23187, on the phosphorylation of, and flux through, phenylalanine hydroxylase in rat liver cells. | the adrenergic amines noradrenaline and adrenaline increased flux through phenylalanine hydroxylase by approx. 50%. this effect, which appears to be mediated by an alpha-adrenergic mechanism, was accompanied by a rapid increase in the phosphorylation of phenylalanine hydroxylase. although ionophore a23187 mimicked the effects of the adrenergic amines, vasopressin was completely without effect on either phenylalanine hydroxylation or enzyme phosphorylation. flux through phenylalanine hydroxylase ... | 1984 | 6426473 |
| effects of saturated and unsaturated dietary fat on aflatoxin b1 metabolism. | male fisher 344 rats were fed diets containing either 20% corn oil, 20% coconut oil or 18% coconut oil plus 2% corn oil for 3 wk. a single dose of [3h]aflatoxin b1 [(3h]afb1) was administered ip and the biliary excretion of aflatoxin metabolites and the binding of 3h to nucleic acids were studied. in other experiments the in vitro metabolism of afb1 by liver postmitochondrial supernatants prepared from rats fed the different sources of dietary fat was determined. the major nonextractable aqueous ... | 1984 | 6427082 |
| sex differences in arachidonate cyclo-oxygenase products in elicited rat peritoneal macrophages. | peritoneal macrophages were elicited by freund's incomplete adjuvant from adult male and female fisher 344 rats. the release of prostaglandin e2 and thromboxane b2 from these macrophages was determined by radioimmunoassay. the basal release of these products was the same for males and females. the macrophages of the female rats released, in a dose-dependent manner, significantly more prostaglandin e2 and thromboxane b2 than macrophages from the male, following challenge with either a particulate ... | 1984 | 6428458 |
| immunochemical characterization of high-molecular-weight polysaccharide from fisher immunotype 3 pseudomonas aeruginosa. | a high-molecular-weight polysaccharide (ps) was isolated from the culture supernatant of a fisher immunotype 3 (it-3) strain of pseudomonas aeruginosa. consistent with previously reported findings for it-1 and it-2 ps, the preparation of it-3 ps was found to be an immunogenic, nontoxic form of the o polysaccharide side chain on the lipopolysaccharide (lps). the it-3 ps was mainly carbohydrate in composition. it was serologically and chemically identical to lps o side chain, but distinct from tha ... | 1984 | 6430805 |
| speed of movement initiation performance predicts differences in [3h]spiroperidol receptor binding in normal rats. | speed of movement initiation is altered in normal aging and in neurological disorders such as parkinson's disease. this study was undertaken to extend our previous results, which suggested a relationship between nigrostriatal dopamine function and an animal model of movement initiation speed (reactive capacity). fisher 344 rats exhibiting exceptionally fast or slow reactive capacity but otherwise normal were examined for differences in the striatal binding of the dopaminergic ligand, [3h]spirope ... | 1984 | 6431475 |
| immunologic investigations of mucoid strains of pseudomonas aeruginosa: comparison of susceptibility to opsonic antibody in mucoid and nonmucoid strains. | mucoid strains of pseudomonas aeruginosa, isolated from patients with cystic fibrosis, were studied for the prevalence of each of the seven fisher immunotype antigens and were compared with their nonmucoid transformants, obtained by repeated subculturing, for susceptibility to opsonic antibody. of the 30 strains tested--one from each of 30 patients--16 were typable and were tested in the opsonophagocytic assay with use of immunotype-specific rabbit antiserum; eight had significant opsonization b ... | 1980 | 6444976 |
| inhibition of prostate tumor growth in two rat models by chronic administration of d-trp6 analogue of luteinizing hormone-releasing hormone. | we have investigated the effect of the d-trp6 analogue of luteinizing hormone-releasing hormone (lh-rh), a superactive analogue of lh-rh, on the growth of two different models of prostate tumors in rats. chronic administration of d-trp6-lh-rh in a dose of 25 micrograms/day for 14-21 days significantly inhibited the growth of the chemically induced squamous cell carcinoma 11095 in fisher 344 male rats. the weights of the ventral prostate and testes were also significantly reduced by treatment wit ... | 1981 | 6458815 |
| bulinus crystallinus (morelet, 1868) acting as intermediate host for schistosoma intercalatum fisher, 1934 in gabon. | | 1984 | 6464139 |
| [primary chemotherapy in breast cancer. preliminary results]. | primary chemotherapy in carcinoma of the breast is justified by the high risk of distant metastases, immunodepression related to surgery and the experimental studies and clinical trials of nissen-meyer in 1967, and fisher in 1968. chemotherapy was associated with loco-regional patey-type surgery (20 patients) or radiotherapy with cobalt and irridium (43 patients) in 63 cases of breast cancer, 33 of which were t4 or in exarcerbation. initial chemotherapy comprised 3 to 6 infusions of velbe, thiot ... | 1984 | 6476666 |
| [effect of perfluorochemicals on tissue po2 levels in a subcutaneous 9l rat glioma model]. | the purpose of this study was to investigate the effect of perfluorochemicals(fluosol-43) and/or oxygen on tissue po2 levels in a subcutaneous 9l rat glioma model. thirty days after subcutaneous implantation of 9l cells in to the flank of fisher 344 rats, tumors contained large central areas of necrosis and showed a heterogeneity in tissue po2 levels. tissue po2 levels in the solid area, border area, and necrotic area were about 45 mmhg, 5 mmhg, and 0 mmhg respectively. more significant elevatio ... | 1984 | 6486835 |
| interaction of purified nicotinamidenucleotide transhydrogenase with dicyclohexylcarbodiimide. | the inhibition of the energy-linked nicotinamidenucleotide transhydrogenase (th; ec 1.6.1.1) by dicyclohexylcarbodiimide (dccd) has been further studied because of its important mechanistic implications. we had shown earlier that th bound to submitochondrial particles from bovine heart is inhibited by dccd and that nad(h) protects the enzyme against this inhibition [phelps, d.c., & hatefi, y. (1981) j. biol. chem. 256, 8217-8221]. by contrast, pennington and fisher [pennington, r.m., & fisher, r ... | 1984 | 6487611 |
| morphologic changes in rat urothelial cells during carcinogenesis: i. histologic and cytologic changes. | the methods of either image or flow cytometry applied to developing bladder tumors in rats requires satisfactory cell samples and a system for cell classification that is related to the lesions from which the cells are derived. seven- to eight-week-old male fisher 344 rats were fed 0.05% of the carcinogen n-butyl-4-n-hydroxybutylnitrosamine (bbn) in drinking water for 10 wk and then returned to tap water. animals were killed at 14, 26, 34, 45 and 62 wk after the start of carcinogen feeding. age- ... | 1984 | 6489059 |
| some aspects of the phosphorylation of phenylalanine 4-monooxygenase by a calcium-dependent and calmodulin-dependent protein kinase. | a calmodulin-dependent protein kinase purified from liver catalyzed the incorporation of up to 0.7 mol of phosphate per mol subunit of phenylalanine 4-monooxygenase. the phosphorylation was accompanied by a proportional increase in the hydroxylase activity. the reaction was ca2+-dependent and was inhibited by physiological concentrations of phenylalanine. phenylalanine 4-monooxygenase was also a substrate for the cgmp-dependent protein kinase, but in this system phenylalanine stimulated the rate ... | 1984 | 6489353 |
| lipid fluidity and composition of intestinal microvillus membranes isolated from rats of different ages. | the lipid composition and fluidity of microvillus (luminal) membranes isolated from the small intestines of fisher 344 rats aged 6, 17, and 117 weeks were compared. lipid fluidity, as assessed by the fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene, was significantly greater in rats aged 6 weeks as compared to 17 or 117 weeks. a lipid thermotropic transition was observed at 17.5 +/- 1.3 degrees c in the membranes of the youngest group, approx. 5-6 degrees c lower than that of the older a ... | 1984 | 6498196 |
| [the effect of preparations of microbial glutamin(asparagin)ase on cultured tumor cells]. | glutamin (asparagin)ase from pseudomonas boreopolis 526 is shown to produce a cytotoxic effect on the human ovary carcinoma cells (caov line), fisher lympholeukemia (l-8 line) and burkitt's lymphoma cells (p3hr line). a significant inhibition of the dna synthesis is found in l-8 and p3hr cell lines. the enzyme is less active in the cells of the caov line. | 1984 | 6499733 |
| [meningeal gliomatosis: development of experimental models]. | experimental models of meningeal gliomatosis (mg) have been produced by intracisternal inoculation of c6 glioma and 9l glioma cells into wistar and fisher 344 rats, respectively. the tumor growth was steady and fast in both mg models if 10(6) cells were implanted. median survival time(mst) of rats inoculated with tumor cells was inversely related to the number of cells inoculated. the clinicopathological features observed in both mg models were similar to those seen in diffuse leptomeningeal inv ... | 1984 | 6504251 |
| increased o- and p-cresol/hippuric acid ratios in the urine of four strains of rat exposed to toluene at thousands-ppm levels. | rats (fisher, wistar, donryu and sprague-dawley strains) were exposed to 5 approximately 3500 ppm toluene for 8 h, and urine samples were analyzed for hippuric acid and cresols. while hippuric acid increased in proportion to the exposure concentration, a sharp increase in o-cresol excretion was observed at high toluene concentrations so that the o-cresol/hippuric acid ratio was elevated after 500 approximately 3500 ppm exposures. changes in the p-cresol: hippuric acid ratio were less marked. the ... | 1984 | 6506100 |
| vasopressin release from individually superfused neurohypophyses decreases in aged rats. | we studied the effect of aging on vasopressin (vp) release from isolated neurohypophyses (nh) individually superfused with synthetic medium tc 199 with hanks' salts. the superfusion technique is described in detail. male fisher 344 rats 2 months (young, n = 17), 12 months (adult, n = 14) and 30 months (old, n = 17) of age were used. vp was measured by radioimmunoassay (ria). the age-related vp release was analyzed as follows: initial traumatic release, basal release, vp release evoked by electri ... | 1984 | 6514137 |
| changes in the plasma concentration of immunoreactive arginine vasotocin during oviposition in the domestic fowl. | the plasma concentrations of immunoreactive arginine vasotocin (avt) were measured during oviposition and shortly before ovulation of the first egg (cl) of a clutch. immunoreactive avt was determined on bentonite extracts of 0.5 ml plasma samples using the method of rosenbloom and fisher (1974). the r-70 antiserum used to measure avt cross reacted with arginine vasopressin (avp), however the fowl pituitary does not synthesise avp. over a period of 10 to 90 min before oviposition the plasma avt c ... | 1984 | 6518411 |
| subchronic inhalation toxicity of dimethylformamide in rats and mice. | fisher f344 rats and b6c3f1 mice were exposed to concentrations of 0, 150, 300, 600 and 1200 ppm of dimethylformamide (dmf) for 6 hours a day, 5 days a week for 12 weeks. detailed clinical observations were obtained weekly and body weights biweekly on all animals. clinical chemistry and hematology evaluations were made on all rats and approximately half the mice at terminal sacrifice. gross necropsy examinations were made on all animals. histopathologic evaluations were conducted on selected tis ... | 1984 | 6534732 |
| [incidence and antibiotic resistance of various species of staphylococci in a hospital environment in eastern sicily]. | in this work we carry out an epidemiologic investigation of the incidence of staphylococci in some hospitals of east sicily, in relation with hospitalized patients. the tests were performed every ten days for a period of four months, by using fisher technique. the strains were isolated from clinical specimens from hospitalized patients, and after identification, we made antibiotics-resistance essays. the results show a correlation between staphylococcus strains isolated from patients and that of ... | 1984 | 6536546 |
| estrone-induced, prolactin-secreting and dopamine-sensitive rat pituitary tumor. | prolactin (prl)-secreting rat pituitary tumors were induced in female fisher 344/lis rats by s.c. implants of estrone (e1) pellets. tumor growth was relatively fast and reached about 100 mg within 2 months. ovariectomy at the time of e1 implants seemed to accelerate the growth of the tumors. tumor cells in primary culture produced mainly prl, while growth hormone (gh) release was about 2% of prl production and the release of some other pituitary hormones did not exceed 1% of prl values. tumor ce ... | 1984 | 6540183 |
| biochemical and histomorphometric characterization of a rat model for humoral hypercalcemia of malignancy. | humoral hypercalcemia of malignancy is a common but incompletely understood syndrome in humans. in an effort to define an animal model of this syndrome, we studied the transplantable rice-500 leydig cell tumor in male fisher rats. animals were studied 4-9, 10-12, and 13-14 days after tumor transplantation. by days 13-14, tumor-bearing animals were significantly hypercalcemic, hypercalciuric, and hyperphosphaturic compared to control animals. fractional phosphorus excretion was elevated 4-fold in ... | 1984 | 6546543 |
| [effects of phenobarbital on the metabolism of acnu in vivo]. | the nitrosourea compounds are often used in the treatment of patients with malignant brain tumors in combination with anticonvulsants, such as phenobarbital (pb). since pb can induce hepatic microsomal enzyme--p 450 and degrade nitrosoureas in vivo, the effect of pb on tumoricidal activity in relation to toxicity of 3-[(4-amino-2-methyl-5-pyrimidinyl)-methyl]-1-(2-chloroethyl)-1-nitrosourea (acnu) was studied using a rat brain tumor model. to determine toxicity, cd-fisher rats were treated for 4 ... | 1983 | 6578801 |
| seminal vesicle secretion iv gene: allelic difference due to a series of 20-base-pair direct tandem repeats within an intron. | the rat seminal vesicle secretion iv (svs iv) gene was isolated from a lambda charon 4a library. the svs iv gene transcription unit was found to be on one 3.3-kilobase (kb) ecori fragment. restriction mapping and dna sequence analysis demonstrated that the entire length of the svs iv transcription unit is 1,930 base pairs (bp) and contains two introns. the 3.3-kb ecori fragment contains 144 bp of 5'-flanking region. at -113 bp from the presumed transcription initiation site an interesting struct ... | 1983 | 6579532 |
| [meningeal gliomatosis models as a chemosensitivity assay system]. | experimental models of meningeal gliomatosis (mg) have been produced by intracisternal inoculation of c6 and 9l glioma cells into wistar and fisher 344 rats, respectively. chemotherapy of these models and in vitro chemosensitivity assay for these cell lines were studied with acnu, bcnu and vm-26. in vitro chemosensitivity assay revealed that 9l cells were sensitive to all of the anticancer drugs above, and that c6 cells were resistant to acnu and bcnu, but not to vm-26. in vivo experiment, the s ... | 1984 | 6584085 |
| [flow cytometric study of enhanced effect of anti-cancer drugs induced by nicardipine hydrochloride]. | flow cytometric analysis was used to study the effect of a calcium influx blocker, nicardipine hydrochloride, on the cytotoxicity of anti-cancer drugs in tumor cells. the parameters used for this study were dna- and protein-cell distribution histograms. cells and drugs used for this study were c6 cells from cd fisher rat glioma and vcr, adm and acnu, respectively. the growth inhibitory effect estimated by concentration at id50 on c6 cells was indicated as follows; vcr showed an 89-fold enhanceme ... | 1984 | 6593005 |
| effects of hypophysectomy and immobilization stress on s-adenosylmethionine levels in rat adrenal glands. | rat adrenal s-adenosylmethionine (sam) levels and phenylethanolamine-n-methyltransferase (pnmt) activity were measured under conditions of hypophysectomy and stress. a new dual-label radioenzymatic assay for sam is presented which eliminates problems found to exist with previous methods. strain-specific differences in both pnmt and sam were found, as well as sex differences in sam levels. immobilization stress resulted in an increase in adrenal sam and pnmt activity, while hypophysectomy decreas ... | 1984 | 6610814 |
| dna repair kinetics in irradiated undifferentiated and terminally differentiated cells. | the brains of male fisher 344 rats bearing 80-150 mg intracerebral 9l/ro tumors were irradiated with doses of 1,250-5,000 rads of x- or gamma-rays. at various times after irradiation, the cerebellum and tumor were excised, dissociated into single cells and the dna from these cells sedimented through alkaline sucrose gradients in zonal rotors with slow gradient reorienting capability. quantitation of the dna repair kinetics demonstrated that the process in both tumor cells and neurons has a fast ... | 1983 | 6611843 |
| androgens as promoters of colon carcinogenesis. | the effects of androgens on colon carcinogenesis were studied in 90 male fisher-344 rats, given 10 weekly subcutaneous (sc) injections of 7.5 mg azoxymethane (aom)/kg body weight, starting at 12 weeks of age. thirty rats received the aom course only (aom only). thirty rats were gonadectomized at 10 weeks of age and underwent the aom course (castrated). in 30 additional castrated rats, hormone substitution was achieved by sc injection of 1 mg dehydrotestosterone (dht) three times a week for 12 we ... | 1983 | 6616504 |
| the effects of amiodarone on serum thyroid hormones and hepatic thyroxine 5'-monodeiodination in rats. | amiodarone (2-n-butyl-3,4'-diethylaminoethoxy-3', 5'-diiodobenzoyl-benzofurane) is an antiarrhythmic drug which increases serum t4 and rt3 levels in patients and lowers serum t3 levels. to investigate its effects on t4 metabolism and its cardiac action, we fed amiodarone to male fisher rats at doses of 5, 15, and 45 mg/kg bw x day; controls received potassium iodide for 4-7 weeks, and another group received sodium ipodate. at 4 weeks, amiodarone caused a dose-dependent increase in the serum t4 c ... | 1983 | 6617581 |
| estimating length density and quantifying anisotropy in skeletal muscle capillaries. | the accurate estimation of stereological parameters defined on anisotropic structures is a long-standing problem. in this paper we seek to estimate the capillary length density jv in skeletal muscle tissue. a well-known model for directional anisotropy in space, namely the 'spherical normal' or 'fisher axial distribution' model, is found to fit the relevant data satisfactorily. based on this model, a short-cut estimation method is proposed and illustrated with a numerical example. this method es ... | 1983 | 6620361 |
| the effect of indomethacin on the growth of epidermoid carcinoma of the palate in rats. | the in vivo effect of indomethacin therapy in head and neck cancer was tested using rats (fisher 344) with implanted epithelial palatal carcinoma. indomethacin was then given to half of the rats in their drinking water, starting two weeks after tumor implantation. the animals were then killed at four weeks and the tumor volumes were measured. it was found that four (21%) of the 19 rats were complete responders and eight (42%) of the 19 rats were partial responders. the control group showed incre ... | 1983 | 6639438 |
| functional brain tissue transplantation: reversal of lesion-induced rotation by intraventricular substantia nigra and adrenal medulla grafts, with a note on intracranial retinal grafts. | using a rotational behavior animal model, it has been found that embryonic substantia nigra (sn) can be homologously transplanted to the brain lateral ventricles to reverse the effects of sn lesions. these grafts were found to decrease the lesion-induced rotational behavior that was provoked either by apomorphine or amphetamine. this effect was not duplicated by grafts of other embryonic brain regions. the sn grafts produced a dopaminergic reinnervation of the dorsomedial striatum that appeared ... | 1983 | 6652162 |
| increased agglutinability of bladder epithelial cells by concanavalin a in rats fed several biphenyl derivatives. | biphenyl and its derivatives, 2-aminobiphenyl, 2-nitrobiphenyl, 4-aminobiphenyl, 4-nitrobiphenyl, p-phenylphenol, o-phenylphenol (opp), and o-phenylphenol sodium salt tetrahydrate (opp-na) were examined for their bladder carcinogenicity in rats by a short-term assay for agglutinability of bladder epithelial cells with concanavalin a. increased agglutinability was observed after 1-week treatment with 2.0% and 1.0% opp, 2.0% and 1.0% opp-na, 0.5 and 0.1% 4-aminobiphenyl, and 0.5% 4-nitrobiphenyl i ... | 1983 | 6654951 |
| the effect of aging on vasopressin system in fisher 344 rats. | vasopressin (vp) was measured by ria in the plasma, neurohypophysis (nh) and hypothalamus (ht) of young (2 months), adult (12 months) and old (30 months) male fisher 344 rats, ten of each age. plasma vp concentration was significantly lower in old compared to adult and to young rats. vp content in the nh expressed per mg weight was similar in all three groups, while the hypothalamic vp content was decreased in the aged rats. this suggests that reduced synthesis and release and/or increased degra ... | 1983 | 6667722 |
| effect of feeding fermented milk on the incidence of chemically induced colon tumors in rats. | the effect of feeding skim milk fermented by streptococcus thermophilus or lactobacillus bulgaricus on the incidence of chemically induced colon tumors was studied in rats. weanling fisher-344 rats were fed chow plus skim milk (sm), chow plus sm fermented by s. thermophilus, chow plus sm fermented by l. bulgaricus, or chow plus water until sacrifice at 36 weeks, or before if moribund. colon tumors were induced by s.c. injections of 1,2-dimethylhydrazine hydrochloride during weeks 3 through 22. t ... | 1983 | 6669478 |
| [histological study of urinary bladder tumor: dna of rat urinary bladder tumor caused by n-butyl-n-(4-hydroxybutyl) nitrosamine and that of human bladder tumor]. | male fisher rats were treated with 0.5% bbn, and the appearance of cancer in the rat's bladder was observed successively. the quantities of dna in the normal and tumorous tissues were compared with those in the bladder cancer excised from man; and, the bladder cancer produced in the rat and that occurring in man were compared. 96 rats were divided into 4 groups, and given 8, 16, 24 or 32 weeks of treatment with bbn. papillomas appeared after administration for 8 weeks, and with subsequent increa ... | 1983 | 6677123 |
| regional vs systemic effect of cis-dichlorodiammine platinum (ii) on squamous cell carcinoma in rats. | utilizing a model that compares the effects of chemotherapeutic agents given regionally vs systemically in the same animal, the effects of cis-dichlorodiammine platinum (ii) (cis-platinum) were evaluated. squamous cell carcinoma was implanted at the bases of both ears of fisher-344 rats. by retrograde cannulation of a branch of the external carotid artery, tumors on the right were treated by intra-arterial infusions of varying doses of cis-platinum while tumors on the left were treated only afte ... | 1983 | 6681693 |