| topographic specificity in the retinocollicular projection of the developing ferret: an anterograde tracing study. | to assess the degree of order exhibited during development by crossed and uncrossed retinocollicular pathways, focal deposits of 1,1'-dioctodecyl-3,3,3'3'-tetramethylinodocarbocyanine perchlorate (dii) were made into the temporal or nasal retina of prenatal and postnatal ferrets. this procedure revealed that the first retinal fibers (from the ipsilateral temporal retina) grow into the superior colliculus at embryonic (e) day 30. both crossed and uncrossed fibers innervate the colliculus by e34. ... | 1998 | 9482231 |
| overrepresentation of horizontal and vertical orientation preferences in developing ferret area 17. | one of the fundamental principles of visual cortical organization is that neurons form a "map" in which neighboring cells have similar orientation preferences. previous anatomical and imaging studies have shown that although the exact layouts of these orientation preference maps vary between individuals, features of iso-orientation domains such as width and spacing appear constant within a species. using chronic optical imaging of intrinsic signals we now demonstrate that in ferret area 17 a lar ... | 1998 | 9482934 |
| unequal representation of cardinal and oblique contours in ferret visual cortex. | we have measured the amount of cortical space activated by differently oriented gratings in 25 adult ferrets by optical imaging of intrinsic signal. on average, 7% more area of the exposed visual cortex was preferentially activated by vertical and horizontal contours than by contours at oblique angles. this anisotropy may reflect the real-world prevalence of contours in the cardinal axes and could explain the greater sensitivity of many animals to vertical and horizontal stimuli. | 1998 | 9482936 |
| cell death in the sexually dimorphic dorsal preoptic area/anterior hypothalamus of perinatal male and female ferrets. | a sexually dimorphic male nucleus (mn) is present in nissl-stained sections through the dorsal (d) preoptic area/anterior hypothalamus (poa/ah) of male ferrets. the mn-poa/ah is composed of a cluster of large cells which is organized in males by the action of estradiol, formed via the neural aromatization of circulating testosterone (t), during the last quarter of a 41-day gestation. several recent studies using rodent species have raised the possibility that the hormone-induced masculinization ... | 1998 | 9485049 |
| effect of dehydroepiandrosterone on hypoxic pulmonary vasoconstriction: a ca(2+)-activated k(+)-channel opener. | in the present study, we investigated the effects of the naturally occurring hormone dehydroepiandrosterone (dhea) on hypoxic pulmonary vasoconstriction (hpvc) in isolated ferret lungs and on k+ currents in isolated and cultured ferret pulmonary arterial smooth muscle cells (fpsmcs). severe alveolar hypoxia (3% o2-5% co2-92% n2) caused an initial increase in pulmonary arterial pressure (ppa) that was followed by a reversal in pulmonary hypertension. maintaining alveolar hypoxia caused a sustaine ... | 1998 | 9486202 |
| cytoskeletal targeting of calponin in differentiated, contractile smooth muscle cells of the ferret. | 1. biochemical and quantitative image analysis methods were used to investigate the anatomical basis for the previously described agonist-induced redistribution of calponin. 2. at 140 nm resolution, the quantitative distribution of calponin in resting cells was statistically indistinguishable from that of filament bundles containing alpha-smooth muscle actin and myosin, but was significantly different from that of filaments containing beta-non-muscle actin. conversely, in stimulated cells, the d ... | 1998 | 9490838 |
| quantitative comparison of autoradioluminographic and radiometric tissue distribution studies using carbon-14 labeled xenobiotics. | the tissue distribution of two 14c drugs were quantitatively compared using the techniques of whole body autoradioluminography (wbal) and radiometry. quantitative analysis of tissue radioactivity in whole body cryosections was accomplished from storage phosphor images using the microcomputer imaging device. after obtaining whole body sections from four frozen rats and three frozen ferrets, each wbal-sectioned specimen was partially thawed before obtaining tissue samples for radiometric analysis. ... | 1998 | 9492392 |
| intrinsic circuitry of the superior colliculus: pharmacophysiological identification of horizontally oriented inhibitory interneurons. | much of what is known about the organization of the superior colliculus is based on the arrangement of its external connections. consequently, there is little information regarding pathways that remain intrinsic to it, even though recent data suggest that a horizontally oriented local circuit may mediate the functional reciprocity among fixation and saccade-related neurons. therefore, the present experiments sought physiological evidence for neurons intrinsic to the superior colliculus that migh ... | 1998 | 9497438 |
| spontaneous ca2+ transients and their transmission in the developing chick retina. | the development of the central nervous system is dependent on spontaneous action potentials and changes in [ca2+]i occurring in neurons [1-4]. in the mammalian retina, waves of spontaneous electrical activity spread between retinal neurons, raising [ca2+]i as they pass [5-7]. in the ferret retina, the first spontaneous ca2+ waves have been reported at postnatal day 2 and are thought to result from the ca2+ influx associated with bursts of action potentials seen in ganglion cells at this time [5- ... | 1998 | 9501073 |
| presence of putative neurotransmitters in the myenteric plexus of the gastrointestinal tract and in the musculature of the urinary bladder of the ferret. | the innervation of the musculature in the ferret stomach, ileum, colon and urinary bladder was investigated using immunohistochemistry in noncolchicin-treated tissues. in the gastrointestinal tract two main subpopulations of myenteric neurones were found: cholinergic neurones expressing choline acetyltransferase (chat), which made up 68, 67 and 67% of the neurones in the stomach, ileum and colon, respectively, and nitrergic neurones containing nitric oxide synthase and nadph-diaphorase (stomach: ... | 1998 | 9507249 |
| mechanisms of gastro-oesophageal reflux in the ferret. | transient lower oesophageal sphincter (los) relaxation is the major mechanism of gastro-oesophageal reflux in humans--an event unassociated with swallowing. mechanisms involved in triggering transient los relaxation are poorly understood, and their further study requires a small animal model. in this study we aimed to establish methods for prolonged ambulant oesophageal manometry in ferrets, and to determine motor events associated with reflux episodes and their triggering by different gastric n ... | 1998 | 9507250 |
| effect of potent urease inhibitor, fluorofamide, on helicobacter sp. in vivo and in vitro. | the therapeutic potential of urease inhibition of helicobacter pylori has been studied by examining the effect of the potent urease inhibitor, fluorofamide (n-(diaminophosphinyl)-4-fluorobenzenamide), on urease activity and bacterial survival in vivo and in vitro. in culture, acid protection in h. pylori was shown to be due to changes in the ph of the medium brought about by the release of ammonia. both the acid protection and the ammonia release were completely blocked by fluorofamide at low do ... | 1998 | 9508511 |
| paf-induced secretory hyperresponsiveness in the ferret trachea to bradykinin and its pharmacological inhibition. | both paf (10 microm) and bradykinin (0.1-10 microm) increased lysozyme (from submucosal gland serous cells (+138 and +45% for paf, 10 microm, and bradykinin, 1 microm, respectively) and albumin (mainly active epithelial transport; +387 and +108%) outputs into the ferret tracheal lumen in vitro and reduced the negativity of the potential difference (pd: -33 and -17%) across the trachea. since paf can cause bronchial smooth muscle hyperresponsiveness, we tested whether these effects were interacti ... | 1997 | 9514626 |
| competition in retinogeniculate patterning driven by spontaneous activity. | when contacts are first forming in the developing nervous system, many neurons generate spontaneous activity that has been hypothesized to shape appropriately patterned connections. in mustela putorius furo, monocular intraocular blockade of spontaneous retinal waves of action potentials by cholinergic agents altered the subsequent eye-specific lamination pattern of the lateral geniculate nucleus (lgn). the projection from the active retina was greatly expanded into territory normally belonging ... | 1998 | 9516112 |
| molecular mimicry of ferret gastric epithelial blood group antigen a by helicobacter mustelae. | molecular mimicry of lewis blood group antigens by helicobacter pylori may be involved in immune evasion by the bacteria and in the pathogenesis of chronic atrophic gastritis. helicobacter mustelae infects ferrets naturally, causing gastritis, and may be involved in ulcerogenesis. the aim of this study was to determine if h. mustelae shows a similar form of molecular mimicry. | 1998 | 9516389 |
| oral administration of a prodrug of the influenza virus neuraminidase inhibitor gs 4071 protects mice and ferrets against influenza infection. | we have recently described gs 4071, a carbocyclic transition-state analog inhibitor of the influenza virus neuraminidase, which has potent inhibitory activity comparable to that of 4-guanidino-neu5ac2en (gg167; zanamivir) when tested against influenza a virus replication and neuraminidase activity in vitro. we now report that gs 4071 is active against several strains of influenza a and b viruses in vitro and that oral gs 4104, an ethyl ester prodrug which is converted to gs 4071 in vivo, is acti ... | 1998 | 9517945 |
| identification of gs 4104 as an orally bioavailable prodrug of the influenza virus neuraminidase inhibitor gs 4071. | gs 4071 is a potent carbocyclic transition-state analog inhibitor of influenza virus neuraminidase with activity against both influenza a and b viruses in vitro. gs 4116, the guanidino analog of gs 4071, is a 10-fold more potent inhibitor of influenza virus replication in tissue culture than gs 4071. in this study we determined the oral bioavailabilities of gs 4071, gs 4116, and their respective ethyl ester prodrugs in rats. both parent compounds and the prodrug of the guanidino analog exhibited ... | 1998 | 9517946 |
| cytosolic and mitochondrial ca2+ signals in patch clamped mammalian ventricular myocytes. | 1. ventricular myocytes isolated from ferret or cat were loaded with the acetoxymethyl ester form of indo-1 (indo-1 am) such that approximately 75% of cellular indo-1 was mitochondrial. the intramitochondrial indo-1 concentration was 0.5-2 mm. 2. myocytes were also voltage clamped (membrane capacitance, cm = 100 pf) and a typical wash-out time constant of cytosolic indo-1 by a patch pipette was found to be approximately 300 s. depolarizations to +110 mv produced graded and progressive cellular c ... | 1998 | 9518700 |
| modulation of l-type calcium current kinetics by sarcoplasmic reticulum calcium release in ferret isolated right ventricular myocytes. | the gigaohm seal patch clamp (whole cell configuration) and an internal perfusion technique were used to study the effects of sarcoplasmic reticulum (sr) calcium release on l-type calcium current (ica,l) in ferret enzymatically isolated right ventricular myocytes. ica,l (22 to 24 degrees c) was isolated by using various sodium- and potassium-free salines, which eliminated or greatly minimized activation of the sodium-calcium exchanger and calcium-activated cation and anion currents. when calcium ... | 1998 | 9520864 |
| control of maximum sarcoplasmic reticulum ca load in intact ferret ventricular myocytes. effects of thapsigargin and isoproterenol. | in steady state, the ca content of the sarcoplasmic reticulum (sr) of cardiac myocytes is determined by a balance among influx and efflux pathways. the sr ca content may be limited mainly by the atp-supplied chemical potential that is inherent in the gradient between sr and cytosol. that is, forward ca pumping from cytosol to sr may be opposed by energetically conservative reverse pumping dependent on intra-sr free [ca]. on the other hand, sr ca loading may be limited by dissipative pathways (pu ... | 1998 | 9524134 |
| ferret adrenal-associated endocrinopathy. | | 1998 | 9524724 |
| inhibition of helicobacter pylori and helicobacter mustelae binding to lipid receptors by bovine colostrum. | helicobacter pylori, the etiologic agent of chronic-active gastritis and duodenal ulcers in humans, and helicobacter mustelae, a gastric pathogen in ferrets, bind to phosphatidylethanolamine (pe), a constituent of host gastric mucosal cells, and to gangliotetraosylceramide (gg4) and gangliotriaosylceramide (gg3). the effect of a bovine colostrum concentrate (bcc) on the interaction of h. pylori and h. mustelae to their lipid receptors was examined. bcc blocked attachment of both species to gg4, ... | 1998 | 9534968 |
| differential atrial versus ventricular activities of class iii potassium channel blockers. | the atrial versus ventricular activities of class iii agents with differing k+ channel blocking profiles were assessed in vitro in ferret atrial and right ventricular papillary muscles. in concentration-effective refractory period (erp) response studies at 2 hz and 32 degreesc, the selective ikr blockers dofetilide, e-4031 and d-sotalol, as well as ibutilide, an ikr blocker also reported to enhance inward na+ current, displayed markedly greater efficacies in increasing atrial erp (+90-110%) vers ... | 1998 | 9536003 |
| large-scale human exposures to rabid or presumed rabid animals in the united states: 22 cases (1990-1996). | to identify common elements of large-scale human exposures to rabid or presumed rabid animals in the united states from 1990 to 1996. | 1998 | 9569151 |
| age-dependent and cell class-specific modulation of retinal ganglion cell bursting activity by gaba. | competition for postsynaptic targets during development is thought to be driven by differences in temporal patterns of neuronal activity. in the ferret visual system, retinal ganglion cells that are responsive either to the onset (on) or to the offset (off) of light exhibit similar patterns of spontaneous bursting activity early in development but later develop different bursting rhythms during the period when their axonal arbors segregate to occupy spatially distinct regions in the dorsal later ... | 1998 | 9570807 |
| lack of relay toxicity in ferret hybrids fed carbaryl-treated prairie dogs. | carbaryl (1-napthol methylcarbamate) is being considered for control of fleas on prairie dogs (cynomys spp.) used in black-footed ferret (mustela nigripes) recovery in the western united states. the potential for relay toxicity in ferrets was determined by feeding carbaryl treated prairie dogs to black-footed ferret x siberian polecat (m. eversmanni) hybrids. adult prairie dogs were treated topically with 2.5 g of commercial 5% carbaryl dust sold as flea powder. after 14 days prairie dogs were k ... | 1998 | 9577785 |
| fos expression in the ferret trigeminal nuclear complex following tooth pulp stimulation. | the aim of this study was to establish which regions of the trigeminal nucleus are activated by tooth pulp stimulation in the normal ferret. the distribution of fos-like immunoreactivity was examined following electrical stimulation of the tooth pulp in the awake and anaesthetized ferret. stimulus-specific labelling was found in subnuclei caudalis and oralis of the trigeminal spinal nucleus. three groups of chronically prepared animals; conscious, anaesthetized (alphaxolone/alphadolone) and anae ... | 1998 | 9578406 |
| zanamivir. | zanamivir is the first of a new class of selective influenza virus neuraminidase inhibitors. it inhibits both influenza a and influenza b virus replication in vitro. in the ferret model of influenza, zanamivir reduced viral replication and diminished pyrexia associated with the infection. repeated passage of influenza virus in the presence of zanamivir could produce resistance in vitro. however, there have been no changes in sensitivity to zanamivir in any influenza virus isolates from patients ... | 1998 | 9585868 |
| comparison of sedative and cardiorespiratory effects of diazepam, acepromazine, and xylazine in ferrets. | the sedative and cardiorespiratory effects of an intramuscular injection of diazepam (3 mg/kg body weight), acepromazine (0.1 mg/kg body weight), or xylazine (2 mg/kg body weight) in ferrets (n = 10, crossover design) was evaluated. time from injection to assuming lateral recumbency was not significantly different between the three drugs. duration of recumbency expressed as mean+/-standard deviation was significantly longer with xylazine (68.3+/-20.8 min) than with diazepam (43.2+/-8.2 min) or a ... | 1998 | 9590452 |
| the development of local, layer-specific visual cortical axons in the absence of extrinsic influences and intrinsic activity. | the laminar specificity of vertical connections in the primary visual cortex (area 17) develops precisely from the outset, leading to the hypothesis that layer-specific axonal targeting is attributable to molecular cues intrinsic to the cortex (lund et al., 1977; katz and callaway, 1992). however, alternative factors that could influence axonal development have not been investigated. this study examines the roles of intrinsic cortical activity and extrinsic influences that could arise from earli ... | 1998 | 9592094 |
| neuropeptide immunoreactivity in ligature-induced neuromas of the inferior alveolar nerve in the ferret. | injury to branches of the trigeminal nerve can sometimes result in persistent dysaesthesia. in an attempt to understand the aetiology of this condition we are currently investigating changes which occur at the injury site. in the present study we have examined the expression of seven neuropeptides, all of which have been implicated in nociceptive transmission, or have previously been shown to have altered expression following nerve injury. in 20 adult ferrets the inferior alveolar nerve was sect ... | 1998 | 9593929 |
| relationship between dye coupling and spontaneous activity in developing ferret visual cortex. | neuronal coupling by gap junctions is common during early development of the brain. coupling is thought to create functional cell assemblies which may be involved in the functional specification of brain areas and the formation of synaptic circuits. in the present study we used slices from the visual cortex of postnatal ferrets to investigate the temporal relationship of gap junction coupling and formation of functional synapses. individual neurons were filled with the gap-junction-permeable dye ... | 1998 | 9600391 |
| human respiratory syncytial virus produces prolonged alterations of neural control in airways of developing ferrets. | a dysfunction of pathways that normally cause contraction or relaxation of airways has been proposed to explain heightened levels of responsiveness produced by various insults to the airway. for example, we previously reported (4) that infection of cotton rats with the human respiratory syncytial virus (hrsv) leads to a significant decrease in an airway's nonadrenergic noncholinergic inhibitory (nanci) response shortly after the infection. in the present study we addressed the more chronic effec ... | 1998 | 9603130 |
| spectral-ripple representation of steady-state vowels in primary auditory cortex. | responses to various steady-state vowels were recorded in single units in the primary auditory cortex (ai) of the barbiturate-anaesthetized ferret. six vowels were presented (/a/, /epsilon/, 2 different /i/'s, and 2 different /u/'s) in a natural voiced and a synthetic unvoiced mode. in addition, the responses to broadband stimuli with a sinusoidally shaped spectral envelope (called ripple stimuli) were recorded in each cell, and the response field (rf), which consists of both excitatory and inhi ... | 1998 | 9604344 |
| animal models for host-pathogen interaction studies. | there is no model of helicobacter pylori infection that exactly mimics the human diseases. in a particular, there are no good models of ulceration or gastric adenocarcinoma. patterns of gastritis induced in the animals tend to be lymphocytic and lack the neutrophil infiltration typical of h. pylori infection in the adult. however, the animal models are starting to provide valuable information with respect to factors involved in the colonisation of the gastric mucosa and the importance of host fa ... | 1998 | 9604440 |
| calcium-binding proteins and gaba reveal spatial segregation of cell types within the developing lateral superior olivary nucleus of the ferret. | chemical characteristics of developing neurons in the superior olivary complex of the ferret were analyzed using immunohistochemical methods. the present report of calcium-binding proteins in the developing and adult superior olivary complex shows distinct distribution patterns for parvalbumin, calbindin, and calretinin in the lateral superior olivary nucleus (lso) of the developing ferret that correspond to distribution patterns for different projection cell types and neurotransmitters. in the ... | 1998 | 9605341 |
| sympathectomy does not affect the early ectopic discharge from myelinated fibres in ferret inferior alveolar nerve neuromas. | ectopic neural activity from damaged axons is thought to contribute to the development of sensory disorders following nerve injury. here we have studied the role of sympathetic fibres in the generation or potentiation of this abnormal activity by determining the effect of predegenerating these fibres. twelve adult ferrets were used in the study and six of them underwent sympathectomy by removal of the left superior cervical ganglion. electrophysiological recordings were made from myelinated axon ... | 1998 | 9605492 |
| neuroregulation of mucus secretion by opioid receptors and k(atp) and bk(ca) channels in ferret trachea in vitro. | 1. opioid agonists inhibit neurogenic mucus secretion in the airways. the mechanism of the inhibition is unknown but may be via opening of potassium (k+) channels. we studied the effect on neurogenic secretion in ferret trachea in vitro of the op1 receptor (formerly known as delta opioid receptor) agonist [d-pen2,5]enkephalin (dpdpe), the op2 receptor (formely kappa) agonist u-50,488h, the op3 receptor (formerly micro) agonist [d-ala2, n-me-phe, gly-ol5]enkephalin (damgo), the atp-sensitive k+ ( ... | 1998 | 9605570 |
| childhood risks from the ferret. | the ferret is becoming an increasingly popular pet, yet the dangers of ferret ownership remain unrecognized by physicians and the general public. reported are three incidents of ferret attacks in a 3-month period of time. the risk of attack is greatest in infants and small children. wounds caused by ferret attacks must be evaluated for injury, infection, and rabies prophylaxis. such attacks should be reported to animal control authorities. physicians need to recognize the ferret as a risk to chi ... | 1998 | 9610971 |
| activation of non-adrenergic non-cholinergic inhibitory pathways by endogenous and exogenous tachykinins in the ferret lower oesophageal sphincter. | repeated oesophageal acidification causes lower oesophageal sphincter (los) relaxation in the anaesthetized ferret which is mediated by a peripheral neurokinin (nk-1) receptor mechanism. our aim in this study was to characterize neural pathways in the los activated by capsaicin and tachykinin receptor agonists in vitro. circular muscle strips of los (two per animal) from a total of 24 ferrets were maintained in organ baths. electrical field stimulation (efs, 50 v, 5-50 hz) caused frequency-depen ... | 1998 | 9614673 |
| the ferret files. | | 1998 | 9616639 |
| lef1 transcription factor expression defines airway progenitor cell targets for in utero gene therapy of submucosal gland in cystic fibrosis. | cystic fibrosis (cf) has emerged as a paradigm disorder for assessing the utility of gene therapy in the treatment of genetic diseases. it is hypothesized that submucosal glands may play an important role in the pathophysiology of cf lung disease. however, this region poses several significant obstacles for gene therapy due to its inaccessibility from the lumen of adult proximal airways. in utero gene therapy to correct submucosal gland dysfunction in cf provides an attractive alternative strate ... | 1998 | 9618379 |
| periodicity of thalamic spindle waves is abolished by zd7288,a blocker of ih. | the actions of the novel bradycardiac agent zd7288 [4-(n-ethyl-n-phenylamino)-1, 2-dimethyl-6-(methylamino)pyrimidinium chloride] were investigated on the hyperpolarization-activated cation current ih and on network activity in spontaneously spindling ferret lateral geniculate (lgnd) slices in vitro using intracellular recording techniques. in voltage-clamp recordings, local application of zd7288 (1 mm in micropipette) resulted in a complete block of ih, whereas in current-clamp recordings, appl ... | 1998 | 9636128 |
| ontogeny of postcanine tooth form in the ferret, mustela putorius (carnivora: mammalia), and the evolution of dental diversity within the mustelidae. | this study describes dental development within the ferret, mustela putorius, through study of the form of the carnassial teeth and the upper first molar at progressive growth stages. primordial teeth were serially sectioned in sagittal and transverse planes and three-dimensional reconstructions of tooth primordia were generated using macreco software. regional growth of the crown and asynchronous maturation of the dental tissues were observed in each tooth. the upper carnassial blade develops ea ... | 1998 | 9642793 |
| potentiation of the contraction following a prolonged depolarization in isolated ferret myocardium. | the contractile force was studied in ferret papillary muscles during voltage clamp depolarizations, using the single sucrose gap method. prolongation of a test depolarization within a train produced potentiation of the following contraction. the effects of varied duration and membrane potential of the test depolarization upon the potentiated force of the following beat were studied. we assumed that force of a beat was an index of calcium entry on the previous depolarization. the relationship bet ... | 1998 | 9648617 |
| diagnosis of mycobacterium microti infections among humans by using novel genetic markers. | as a result of dna typing of mycobacterium microti isolates from animals in the united kingdom and the netherlands, we diagnosed four human m. microti infections. these are the first m. microti infections among humans to be reported. three of the patients were immunocompromised and suffered from generalized forms of tuberculosis. the fourth patient was a 34-year-old immunocompetent male with a persistent cough and undefined x-ray abnormalities. two of the m. microti infections were recognized by ... | 1998 | 9650922 |
| the interaction of neuraminidase and hemagglutinin mutations in influenza virus in resistance to 4-guanidino-neu5ac2en. | we have previously described a 4-guanidino-neu5ac2en (zanamivir)-resistant neuraminidase (na) variant g70c4-g, with an active site mutation glu 119 to gly. this variant has been found to also harbor a hemagglutinin (ha) mutation in the receptor binding site, ser 186 to phe. examination of early passages of the g70c4-g virus revealed that this ha mutation had arisen by the first passage. from a subsequent passage two transient variants were isolated which had each acquired a different second ha m ... | 1998 | 9656997 |
| the unimportance of being (protein kinase c) epsilon. | the purpose of our study was to determine the mechanism through which phorbol esters and smooth muscle myosin phosphatase inhibitors can induce contraction of smooth muscle in the absence of ca2+. protein kinase c-epsilon (pkc-epsilon) was previously implicated in this process based largely on its supposed absence in the ferret portal vein, and a correlation was drawn between the presence of this isoform and the ability of smooth muscle to contract independently of ca2+ and phosphorylation of th ... | 1998 | 9657521 |
| insulin-like growth factor-1 but not growth hormone augments mammalian myocardial contractility by sensitizing the myofilament to ca2+ through a wortmannin-sensitive pathway: studies in rat and ferret isolated muscles. | a growing body of evidence has been accumulated recently suggesting that growth hormone (gh) and insulin-like growth factor-1 (igf-1) affect cardiac function, but their mechanism(s) of action is unclear. in the present study, gh and igf-1 were administered to isolated isovolumic aequorin-loaded rat whole hearts and ferret papillary muscles. although gh had no effect on the indices of cardiac function, igf-1 increased isovolumic developed pressure by 24% above baseline. the aequorin transients we ... | 1998 | 9670918 |
| the role of the medullary raphe nuclei in regulation of cholinergic outflow to the airways. | in these studies we determined the role of the medullary midline nuclei on a cholinergic outflow to the airways by examining the response of tracheal tone and lung resistance to pharmacological stimulation. studies were performed on alpha-chloralose-anesthesized, paralyzed and mechanically ventilated cats, and ferrets. l-glutamate microinjection into the medullary midline neurons significantly decreased tracheal tension, and reduced lung resistance. these effects were abolished by prior topical ... | 1998 | 9672125 |
| molecular characterization of mouse pneumocystis carinii surface glycoprotein a. | since the mouse offers an easily manipulated experimental animal model for the study of the immunopathogenesis of pneumonia caused by the opportunist pneumocystis carinii, we cloned and characterized cdnas encoding an abundant, immunogenic surface antigen termed glycoprotein a (gpa) from mouse p. carinii. a cdna library was constructed in bacteriophage lambda gt11 from p. carinii-infected mouse lung poly(a+) rna. using a nucleic acid probe derived from a conserved region of the mouse p. carinii ... | 1998 | 9679195 |
| changes in ventricular repolarization during acidosis and low-flow ischemia. | myocardial ischemia, primarily a metabolic insult, is also defined by altered cardiac mechanical and electrical activity. we have investigated the metabolic contributions to the electrophysiological changes during low-flow ischemia (7.5% of the control flow) using 31p nmr spectroscopy to monitor metabolic parameters, suction electrodes to study epicardial monophasic action potentials, and 86rb as a tracer for k+-equivalent efflux during low-flow ischemia in the langendorff-perfused ferret heart. ... | 1998 | 9683444 |
| ultrasonography of the adrenal glands in the dog, cat, and ferret. | ultrasonography has become an important modality for imaging adrenal glands in small animals. normal adrenal glands and structural abnormalities, such as changes in size, shape, and echogenicity, can be identified. in the case of adrenal tumors, ultrasonography is a valuable tool for identifying neoplastic masses with local and regional involvement, as well as potential abdominal metastases. when correlated with clinical findings and results of hematologic, serum biochemical and endocrine tests, ... | 1998 | 9698619 |
| preservation of the in vivo phosphorylation status of phospholamban in the heart: evidence for a site-specific difference in the dephosphorylation of phospholamban. | the phosphorylation status of the cardiac sarcoplasmic reticular (sr) protein phospholamban determines the activity of the sr ca(2+)-atpase. in order to predict sr ca2+ transport in vivo, it is vital that techniques used to measure the phosphorylation status of phospholamban adequately clamp the endogenous kinases and phosphatases which modify phosphorylation during sample preparation. a recent study (boateng, s., seymour, a-m., dunn, m., yacoub, m., and boheler, k. (1997) biochem. biophys. res. ... | 1998 | 9703990 |
| bilateral perinephric pseudocysts and polycystic kidneys in a ferret. | a 3-year-old castrated male domestic ferret was evaluated for abdominal distention. survey lateral and dorsoventral abdominal radiographs were made. there were two soft tissue radiopacities consistent with grossly enlarged kidneys displacing small bowel and colon cranially, ventrally and caudally. abdominal ultrasound was performed and revealed bilateral perinephric pseudocysts and polycystic kidneys. the perinephric pseudocysts were found to be dilated renal capsules on exploratory surgery and ... | 1998 | 9710132 |
| errors in quiz corner question on ferrets. | | 1998 | 9711382 |
| a traveling wave of lateral movement coordinates both turning and forward walking in the ferret. | relative phase was recently suggested as a key variable for the dynamical modeling of coordination in both quadruped locomotion and undulation swimming in fish. relative phase analysis has not yet been applied, however, to the behavior of intact, freely moving animals, but only to simplified situations involving restrained animals and humans. in order to investigate relative phase under free movement conditions, we filmed free locomotion of ferrets (mustella putorius) from below (through a glass ... | 1998 | 9711818 |
| molecular cloning of the bile salt-dependent lipase of ferret lactating mammary gland: an overview of functional residues. | ferret lactating mammary gland bile salt-dependent lipase (bsdl, ec 3.1.1.-) has been cloned by rt-pcr. the open reading frame consists of 1869 nucleotides which encode 623 amino acids of the functional enzyme. when compared to other species, the greatest homology is observed between residues 1 and 484, with little or no homology at the c-terminal end where seven repeated segments of similar sequence are located. ferret mammary gland bsdl retains residues involved in the active site and the tent ... | 1998 | 9714751 |
| the role of nitric oxide in the control by the vagal nerves of the heart of the ferret. | this study focuses on the potential role for nitric oxide on the actions of the parasympathetic innervation to the heart. earlier, we showed that the nitric oxide synthase (nos) inhibitor n omega-nitro-l-arginine methyl ester (l-name) reduced the bradycardia induced by stimulation of vagal efferent motor fibres and that these effects are reversible through administration of the nos substrate l-arginine. in the present study, we show that d-arginine does not reverse the effects of the inhibitors ... | 1998 | 9717069 |
| the zeta cell: a new ganglion cell type in cat retina. | we define a new morphological type of ganglion cell in cat retina by using intracellular staining in vitro. the zeta cell has a small soma, slender axon, and compact, tufted, unistratified dendritic arbor. dendritic fields were intermediate in size among cat ganglion cells, typically twice the diameter of beta cell fields. they were smallest in the nasal visual streak (<280 microm diameter), especially near the area centralis (60-150 microm diameter), and largest in the nonstreak periphery (maxi ... | 1998 | 9721908 |
| action potential shortening through the putative beta4-adrenoceptor in ferret ventricle: comparison with beta1- and beta2-adrenoceptor-mediated effects. | the electrophysiological responses to (-)-cgp 12177 ((-)-4-(3-tertiarybutylamino-2-hydroxypropoxy) benzimidazol-2-one), an agonist for the putative beta4-adrenoceptor, were investigated on isolated perfused ferret hearts paced at 100 min(-1) and compared to those of (-)-noradrenaline and (-)-adrenaline, mediated through beta1- and beta2-adrenoceptors respectively. the three agonists decreased ventricular monophasic action potential duration but prolonged the action potential plateau; beta3-adren ... | 1998 | 9723943 |
| comparison of anesthetic and cardiorespiratory effects of diazepam-butorphanol-ketamine, acepromazine-butorphanol-ketamine, and xylazine-butorphanol-ketamine in ferrets. | ten ferrets were used in a crossover study to determine the sedative effects of intramuscularly administered diazepam (3 mg/kg body weight)-butorphanol (0.2 mg/kg body weight)-ketamine (15 mg/kg body weight); acepromazine (0.1 mg/kg body weight)-butorphanol (0.2 mg/kg body weight)-ketamine (15 mg/kg body weight); and xylazine (2 mg/kg body weight)-butorphanol (0.2 mg/kg body weight)-ketamine (15 mg/kg body weight). all of the ferrets became laterally recumbent following the administration of eac ... | 1998 | 9728472 |
| granisetron, a 5-ht3 receptor antagonist, inhibited cisplatin-induced 5-hydroxytryptamine release in the isolated ileum of ferrets. | we investigated the influence of granisetron, a 5-ht3 receptor antagonist, on the increase in 5-hydroxytryptamine (5-ht) release induced by cisplatin from the isolated ileum of the ferret, a species known to vomit in response to cisplatin. 2-methyl-5-ht, a selective 5-ht3 receptor agonist, increased the release of 5-ht from the ferret ileum in a concentration-dependent manner within the range of 10(-7) to 10(-6)m. the 5-ht release induced by 2-methyl-5-ht was significantly inhibited by a concomi ... | 1998 | 9730004 |
| mechanism for the cardioprotective effects of the calcium channel blocker clentiazem during ischemia and reperfusion. | to elucidate whether or not ca channel blockers have an intrinsic benefit that cannot be attributed to the reduction of ca2+ entry by pretreatment, time-averaged intracellular ca2+ concentration ([ca2+]i) and energy-related phosphates were measured in isolated ferret hearts using nuclear magnetic resonance. in the drug-free ischemic group, [ca2+]i increased significantly during 30 min of global ischemia at 30 degrees c and during 0-5 min of reperfusion. after 30 min of reperfusion, isovolumic le ... | 1998 | 9741740 |
| functional and ionic properties of a slow afterhyperpolarization in ferret perigeniculate neurons in vitro. | intracellular recordings from spontaneously spindling gabaergic neurons of the ferret perigeniculate nucleus in vitro revealed a fast afterhyperpolarization after each action potential, a medium-duration afterhyperpolarization after each low-threshold ca2+ spike, and a slow afterhyperpolarization after the cessation of spindle waves. the slow afterhyperpolarization was associated with an increase in membrane conductance, and the reversal potential was sensitive to extracellular [k+]o, indicating ... | 1998 | 9744934 |
| the carboxyl terminus of pneumocystis carinii glycoprotein a encodes a functional glycosylphosphatidylinositol signal sequence. | pneumocystis carinii pneumonia is a hallmark disease associated with aids. an abundant glycoprotein, termed gpa, on the surface of p. carinii is considered an important factor in host-parasite interactions. the primary structure of ferret p. carinii gpa contains a carboxyl-terminal sequence characteristic of a signal for glycosylphosphatidylinositol (gpi) anchors. here we report the capacity for this gpa carboxyl sequence to direct attachment of a secreted protein, human growth hormone (hgh), to ... | 1998 | 9748303 |
| dirofilariasis in the domestic ferret. | the popularity of pet ferrets in heartworm-endemic and -nonendemic areas is growing, with ferret ownership in the united states currently exceeding 10 million. the domestic ferret (mustela putorius furo) has been reported to be susceptible to naturally-acquired and experimentally-induced infections of dirofilaria immitis. host-parasite relationships between d. immitis and domestic dogs and cats have been well studied, but there have been relatively few reports on infections in ferrets. laborator ... | 1998 | 9753800 |
| a role for map kinase in differentiated smooth muscle contraction evoked by alpha-adrenoceptor stimulation. | the purpose of this study was to investigate the potential role of mitogen-activated protein (map) kinase in smooth muscle contraction by monitoring map kinase activation, caldesmon phosphorylation, and contractile force during agonist stimulation. isometric tension in response to kcl and phenylephrine (pe) was measured from strips of ferret aorta. map kinase activation was monitored by western blot using a phosphospecific p44/p42 map kinase antibody. caldesmon phosphorylation was assessed using ... | 1998 | 9755061 |
| temporal, spatial, and oxygen-regulated expression of hypoxia-inducible factor-1 in the lung. | hypoxia-inducible factor (hif)-1 is a basic helix-loop-helix transcription factor that transactivates genes encoding proteins that participate in homeostatic responses to hypoxia. several of these downstream gene products, such as erythropoietin, vascular endothelial growth factor, heme oxygenase-1, and inducible nitric oxide synthase, may contribute to the pathogenesis of pulmonary hypertension. previous studies demonstrated increased hif-1 mrna levels in rats and mice subjected to hypoxia. in ... | 1998 | 9755115 |
| nerve fibers immunoreactive to calcitonin gene-related peptide, substance p, neuropeptide y, and dopamine beta-hydroxylase in innervated and denervated oral tissues in ferrets. | the effect of sensory and sympathetic denervation on the localization and distribution of nerve fibers immunoreactive (ir) to calcitonin gene-related peptide (cgrp), substance p (sp), neuropeptide y (npy), and dopamine beta-hydroxylase (dbh) was studied in the dental pulp, periodontal ligament (pdl), and gingiva in ferrets. unilateral axotomy was performed by resection of the inferior alveolar nerve (ian) 10 days before the experiment (group 1); sympathectomy, by unilateral removal of the cervic ... | 1998 | 9765014 |
| spatial-frequency tuning and geniculocortical projections in the visual cortex (areas 17 and 18) of the pigmented ferret. | we have examined the spatial-frequency selectivity of neurons in areas 17 and 18 of the adult pigmented ferret, by measuring how the amplitude of response depends on the spatial-frequency of moving sinusoidal gratings of optimal orientation and fixed contrast. neurons in area 17 of the ferret respond optimally to low spatial frequencies [average 0.25 cycles per degree (c/deg)], much lower than the optima for cat area 17. the tuning curves are of the same form as those found in cat and monkey: un ... | 1998 | 9767395 |
| an in vitro study of the properties of vagal afferent fibres innervating the ferret oesophagus and stomach. | 1. a novel preparation of the oesophagus with attached vagus nerve from the ferret maintained in vitro was used to study the properties of single vagal afferent nerve fibres with identified receptive fields. 2. recordings were made from three types of gastro-oesophageal vagal afferent fibres that were classified on the basis of their sensitivity to mechanical stimulation. there were those responding to mucosal stroking (mucosal receptors), to circular tension (tension receptors) and those respon ... | 1998 | 9769431 |
| large somal size is associated with the expression of galanin but not with neuronal birthdate in the sexually dimorphic male nucleus of ferret's preoptic area/anterior hypothalamus. | using nissl and golgi stains, a sexually dimorphic male nucleus (mn) comprised of a cluster of large cells with large dendritic arbors has been identified in the dorsal preoptic area/anterior hypothalamus (poa/ah) of male ferrets. the mn-poa/ah is formed only in males by the action of estradiol derived from the neural aromatization of testosterone during the last quarter of a 41-day gestation. the ferret's dorsal poa/ah is also characterized by a sex difference in the expression of the neuropept ... | 1998 | 9772338 |
| vaccine injection-site sarcoma in a ferret. | | 1998 | 9776987 |
| the effect of tasuldine, a bronchosecretolytic agent, on mucus rheology and clearability and the interaction with acetylcholine in ferrets. | tasuldine (ts) is an orally active bronchosecretolytic agent shown to be clinically effective in human studies. tasuldine decreases the sialomucin content of the mucus and, in animal studies, this modulation of the glycopeptide correlates with decreased mucus viscosity. the aim of this study was to evaluate the effect of tasuldine on mucus viscoelasticity and correlate the rheological changes to mucociliary and cough clearability. tracheal mucus samples were collected from anaesthetized adult fe ... | 1997 | 9778490 |
| brainstem inputs to the ferret medial geniculate nucleus and the effect of early deafferentation on novel retinal projections to the auditory thalamus. | following specific neonatal brain lesions in rodents and ferrets, retinal axons have been induced to innervate the medial geniculate nucleus (mgn). previous studies have suggested that reduction of normal retinal targets along with deafferentation of the mgn are two concurrent factors required for the induction of novel retino-mgn projections. we have examined, in ferrets, the relative influence of these two factors on the extent of the novel retinal projection. we first characterized the inputs ... | 1998 | 9779945 |
| evidence for zanamivir resistance in an immunocompromised child infected with influenza b virus. | zanamivir, a neuraminidase inhibitor, has shown promise as a drug to control influenza. during prolonged treatment with zanamivir, a mutant virus was isolated from an immunocompromised child infected with influenza b virus. a hemagglutinin mutation (198 thr-->ile) reduced the virus affinity for receptors found on susceptible human cells. a mutation in the neuraminidase active site (152 arg-->lys) led to a 1000-fold reduction in the enzyme sensitivity to zanamivir. when tested in ferrets, the mut ... | 1998 | 9780244 |
| immunophenotypic characterization of lymphomas from the mediastinum of young ferrets. | to determine the phenotype of naturally developing lymphomas in young ferrets. | 1998 | 9781462 |
| depletion of acinar secretory granules in the ferret parotid gland: effects of substance p and vasoactive intestinal peptide. | the acinar cells of the ferret parotid gland are supplied with parasympathetic nerve fibres containing vasoactive intestinal peptide (vip) and substance p. in this study intracarotid infusions of the two peptides (0.5-1.0 microgram kg-1 min-1 of each for 40 min) in the pentobarbitone-anaesthetized ferret, treated with atropine and adrenoceptor antagonists, induced a loss of acinar secretory granules from this gland, by 32 % in response to vip and by 46 % in response to substance p. stimulation o ... | 1998 | 9782183 |
| modelling the mechanical properties of cardiac muscle. | a model of passive and active cardiac muscle mechanics is presented, suitable for use in continuum mechanics models of the whole heart. the model is based on an extensive review of experimental data from a variety of preparations (intact trabeculae, skinned fibres and myofibrils) and species (mainly rat and ferret) at temperatures from 20 to 27 degrees c. experimental tests include isometric tension development, isotonic loading, quick-release/restretch, length step and sinusoidal perturbations. ... | 1998 | 9785944 |
| establishment of patterned thalamocortical connections does not require nitric oxide synthase. | subplate neurons are early-generated neurons that project into the overlying neocortex and are required for the formation of ocular dominance columns. a subset of subplate neurons express nitric oxide synthase (nos) and produce nitric oxide (no), a neuronal messenger thought to be involved in adult hippocampal synaptic plasticity and also in the establishment of certain specific connections during visual system development. here, we examine whether the nos-containing subplate neurons are involve ... | 1998 | 9786989 |
| genetic heterogeneity in pneumocystis carinii: an introduction. | molecular techniques have played an important role in demonstrating a high level of heterogeneity among the different types of organisms which are collectively known as pneumocystis carinii. genetic heterogeneity has been observed in pneumocystis organisms isolated from different host species, suggesting that pneumocystis infection is host-species specific. on the basis of this genetic divergence a provisional trinomial nomenclature has been adopted, in which different types of pneumocystis orga ... | 1998 | 9792056 |
| the genome of pneumocystis carinii. | the best understood special form of p. carinii, p. carinii formae specialis (f.sp.) carinii, appears to be haploid and contains about 8 million base pairs of dna (8.5 fg) per nucleus. the genome of p. carinii f.sp. carinii is divided into 13-15 linear chromosomes that range from 300 to 700 kb in size. eight different p. carinii f.sp. carinii karyotypes have been observed. the karyotypes of p. carinii f.sp. carinii differ due to slight variations in the lengths of chromosomes, but the 8 karyotype ... | 1998 | 9792057 |
| animal models of pneumocystosis. | as in vitro culture systems allowing to isolate pneumocystis samples from patients or other mammal hosts are still not available, animal models have critical importance in pneumocystis research. the parasite was reported in numerous mammals but p. carinii pneumonia (pcp) experimental models were essentially developed by using rats, mice, rabbits and ferrets. the rat treated with corticosteroids for 9-12 weeks is a useful pcp model. like laboratory rats, conventional mice develop pcp after prolon ... | 1998 | 9792075 |
| f2-isoprostane generation in isolated ferret lungs after oxidant injury or ventilated ischemia. | pulmonary edema develops when pulmonary blood flow is interrupted, then restored. because the lung is not always hypoxic when ischemic, mechanisms of pulmonary ischemia-reperfusion injury are likely to differ from systemic organs, where reactive oxygen species generated during reperfusion mediate organ dysfunction. we previously showed that pulmonary vascular permeability of isolated ferret lungs increased prior to reperfusion, if ventilation was maintained while blood flow was impaired. to dete ... | 1998 | 9801071 |
| signals from the superficial layers of the superior colliculus enable the development of the auditory space map in the deeper layers. | we have examined whether the superficial layers of the superior colliculus (sc) provide the source of visual signals that guide the development of the auditory space map in the deeper layers. anatomical tracing experiments with fluorescent microspheres revealed that a retinotopic map is present in the newborn ferret sc. aspiration of the caudal region of the superficial layers of the right sc on postnatal day 0 did not cause a reorganization of this projection. consequently, recordings made when ... | 1998 | 9801378 |
| characterization of neural control and contractile function in airway smooth muscle of the ferret. | several recent studies have characterized neuroanatomical and neurophysiological aspects of ferret airways, but regional differences in reactivity and cholinergic, adrenergic and non-adrenergic-non-cholinergic (nanc) neural responses have not been examined. the aim of this study was to characterize the contractile and relaxant response elicited by electrical field stimulation (efs), and the contractions induced by cholinergic agonists in isolated ferret tracheal and bronchial preparations. efs p ... | 1998 | 9802964 |
| structural optimization affording 2-(r)-(1-(r)-3, 5-bis(trifluoromethyl)phenylethoxy)-3-(s)-(4-fluoro)phenyl-4- (3-oxo-1,2,4-triazol-5-yl)methylmorpholine, a potent, orally active, long-acting morpholine acetal human nk-1 receptor antagonist. | structural modifications requiring novel synthetic chemistry were made to the morpholine acetal human neurokinin-1 (hnk-1) receptor antagonist 4, and this resulted in the discovery of 2-(r)-(1-(r)-3, 5-bis(trifluoromethyl)phenylethoxy)-3-(s)-(4-fluoro)phenyl-4-(3-ox o-1 ,2,4-triazol-5-yl)methyl morpholine (17). this modified compound is a potent, long-acting hnk-1 receptor antagonist as evidenced by its ability to displace [125i]substance p from hnk-1 receptors stably expressed in cho cells (ic5 ... | 1998 | 9804700 |
| oesophagitis-induced changes in capsaicin-sensitive tachykininergic pathways in the ferret lower oesophageal sphincter. | prolonged oesophageal acidification may impair lower oesophageal sphincter (los) function in reflux disease. the aim of this study was to investigate aspects of altered los innervation in a model of oesophagitis. oesophagitis was induced by acid (hcl, 0.15 m) and pepsin (0.1% w/v) infusions in anaesthetized ferrets. los muscle strip responses to the following stimuli were measured in vitro from control and acid/pepsin-treated ferrets: electrical field stimulation (efs; 1-50 hz), potassium chlori ... | 1998 | 9805316 |
| conditioned antisickness: indirect evidence from rats and direct evidence from ferrets that conditioning alleviates drug-induced nausea and emesis. | in a direct test of conditioned antisickness (cas; b. t. lett, 1983) theory, the authors measured emesis in ferrets and found those with a history of forward pairings of pentobarbital and lithium to have fewer and shorter bouts of emesis on test, whether induced by lithium or, in a subsequent test, by the highly emetogenic anticancer drug cisplatin. in an indirect test of her cas theory, b. t. lett (1992) paired interoceptive (drug) or place cues with lithium chloride toxicosis and found that ra ... | 1998 | 9805793 |
| saphenous vein puncture for blood sampling of the mouse, rat, hamster, gerbil, guinea pig, ferret and mink. | a method is described for blood collection from the lateral saphenous vein. this enables rapid sampling, which if necessary can be repeated from the same site without a need for new puncture wounds. the method is a humane and practical alternative to cardiac and retro-orbital puncture, in species where venepuncture has traditionally been regarded as problematic. | 1998 | 9807749 |
| effects of gr203040, an nk1 antagonist, on radiation- and cisplatin-induced tissue damage in the ferret. | 1. the effects of gr203040, a tachykinin neurokinin1 receptor antagonist, on tissue damage induced by x-irradiation (rad) or cisplatin (cisp) were investigated in ferrets. 2. gr203040 (0.3 mg/kg sc) reduced the rad-induced plasma protein extravasation (ppe) in the duodenum and kidney by 25% in each tissue. 3. gr203040 (3 mg/kg sc, 5-min pretreatment and every 8 hr for 48 hr after cisp) reduced the cisp-induced ppe in the duodenum, jejunum and lung by 59, 52 and 60%, respectively. 4. histological ... | 1998 | 9809472 |
| effects of granisetron and its combination with dexamethasone on cisplatin-induced delayed emesis in the ferret. | 1. granisetron and its combination with dexamethasone for the treatment of delayed emesis following cisplatin (cddp) administration were investigated using ferrets. 2. cddp-induced emesis was significantly inhibited in both the granisetron group and the combined granisetron and dexamethasone group during the acute and delayed phase in terms of total emesis, latency to first emesis and duration of emesis. 3. food and water consumption in the combined group of ferrets was significantly increased a ... | 1998 | 9809477 |
| cystic prostatic disease associated with adrenocortical lesions in the ferret (mustela putorius furo). | a review of case materials at the armed forces institute of pathology identified six cases of prostatitis in domestic ferrets (mustela putorius furo). five of these ferrets (83%) had one or more cysts and the remaining ferret had a paraprostatic cyst. three of the six ferrets (50%) exhibited various degrees of prostatic squamous metaplasia. inflammation ranged from subacute to chronic-active or pyogranulomatous. in addition to the prostatic lesions, hyperplastic and/or neoplastic adrenocortical ... | 1998 | 9823599 |
| insulinoma in the ferret: clinical findings and treatment comparison of 66 cases. | the clinical signs and surgical findings were reported for 66 ferrets with insulinomas confirmed histologically. all of the ferrets were treated with one of three modalities, and disease-free intervals and survival times were gathered to determine the most effective treatment. the three treatment groups included 10 ferrets treated medically, 27 ferrets treated with pancreatic nodulectomy, and 29 ferrets treated with pancreatic nodulectomy combined with a partial pancreatectomy. the mean disease- ... | 1998 | 9826281 |
| evidence for diverse pathways of hypophysiotropic hormone transport in mammals. | comparative studies of mammalian hypothalamic-pituitary relationships have revealed striking variations in hypophysiotropic systems and in portal vascular architecture. immunocytochemical studies indicate that mammalian gnrh, ghrh and somatostatin systems can project to all portions of the neurohypophysis (median eminence, infundibular stem and pituitary neural lobe). in rats, primary secretion sites are located within the median eminence and upper infundibular stem, whereas in bats, most projec ... | 1998 | 9827008 |
| interspecies variations in oral epithelial cytokeratin expression. | the aim of this study was to determine the degree to which the epidermis and oral epithelium of species other than man express cytokeratin (ck) intermediate filaments, which are markers of epithelial differentiation. fixed, wax-embedded samples of skin, buccal mucosa and gingiva from rhesus monkey, marmoset, cow, sheep, pig, ferret, hamster, axolotl and trout were tested for ck expression using a panel of antihuman ck antibodies and an immunoperoxidase procedure. human skin and oral mucosa were ... | 1998 | 9827634 |
| sex difference and testosterone modulation of pheromone-induced neuronalfos in the ferret's main olfactory bulb and hypothalamus. | a carnivore, the ferret possesses a vomeronasal organ--accessory olfactory bulb (vno-aob) projection to the hypothalamus; however, little is known about its function. pheromones in soiled bedding from estrous female ferrets or an artificial peppermint odor significantly augmented nuclear fos protein immunoreactivity (fos-ir), a marker of neural activation, in several main olfactory bulb (mob) sites but not in the aob of gonadectomized male and females. testosterone propionate (tp) significantly ... | 1998 | 9828192 |
| the host range of chronic wasting disease is altered on passage in ferrets. | chronic wasting disease (cwd), a member of the transmissible spongiform encephalopathies (tses), was first identified in captive mule and black-tail deer in 1967. due to the failure to transmit cwd to rodents, we investigated the use of ferrets (mustela putorius furo) as a small animal model of cwd. the inoculation of cwd into ferrets resulted in an incubation period of 17-21 months on primary passage that shortened to 5 months by the third ferret passage. the brain tissue of animals inoculated ... | 1998 | 9837794 |
| the role of semantic context and memory in the acquisition of novel nouns. | three studies assessed the ability of 2-year-olds to use semantic context to infer the meanings of novel nouns and to retain those meanings a day later. in the first experiment, 24 2-year-olds heard novel nouns in sentences that contained semantically constraining verbs (e.g., "mommy feeds the ferret"). they chose from a set of four novel object pictures to indicate the referent. children learned a majority of the novel words. however, they occasionally failed to choose the correct object even w ... | 1998 | 9839419 |