TitleAbstractYear(sorted ascending)
replication of dna in mammalian chromosomes: isolation of replicating segments.from chinese hamster cells, blocked at the beginning of the s phase by treatment with fluorodeoxyuridine and pulse-labeled with [(3)h]thymidine, one can release segments of native dna containing template polyuncleotide chains and the most recently replicated dna. the segments, which can be released without shear by lysis at temperatures below the melting point for the double helix, can be separated from both the nascent single chains (okazaki pieces) and the long strands of native dna in sodium ...19734268701
interallelic complementation in hybrid cells derived from chinese hamster diploid clones deficient in hypoxanthine-guanine phosphoribosyl-transferase activity. 19734570359
phosphorylation of high-molecular-weight membrane protein species in chinese-hamster ovary cells in culture: effect of 6-n,2'-o-dibutyryladenosine 3':5'-cyclic monophosphate plus testosterone.growth of chinese-hamster ovary cells in [(32)p]phosphate and [(3)h]leucine and subsequent assay of the plasma membranes reveals phosphorylation in two protein regions corresponding to molecular weights of 280000 and 195000. culture in the presence of the 6-n,2-o'-dibutyryl derivative of cyclic amp plus testosterone does not stimulate [(32)p]-phosphate incorporation, but determines a modification in the qualitative pattern of phosphorylation.19734353384
evidence for pleiotropic changes in lines of chinese hamster ovary cells resistant to concanavalin a and phytohemagglutinin-p.lines of chinese hamster ovary cells resistant to the lectins concanavalin a (con a) and phytohemagglutinin-p (pha-p) have been isolated and characterized. lines were isolated by a stepwise, a single-step, or a cycling single-step procedure, from both mutagen-treated and untreated cultures. the resistant lines showed a higher efficiency of colony formation in the presence of the appropriate lectin than did the wild-type parental line. the cell lines resistant to con a did not exhibit any detecta ...19734347206
initiation and continuation of dna replication are not associated with the nuclear envelope in mammalian cells.for determination of whether dna replication is initiated at the nuclear envelope, synchronized chinese hamster ovary cells labeled with [(3)h]thymidine were examined by electron microscope radioautography. the cells were synchronized initially by mitotic shake-off and held at the g(1)-s border by 5-fluorodeoxyuridine plus amethopterin. cells were fixed at 1, 5, 10, and 30 min after the inhibitors were counteracted with [(3)h]thymidine. radioautographic silver grains in each case were present ov ...19734268475
radiation-induced cycle delay in synchronized chinese hamster cells: comparison between dna synthesis and division. 19734695230
cytotoxicity and mutagenicity of ultraviolet irradiation as a function of the interval between split doses in cultured chinese hamster cells. 19734684406
relative radiosensitivities of tetraploid and diploid chinese hamster cells in culture exposed to ionizing radiation. 19734684404
caffeine potentiation of the chromosome damage produced in bean root tips and in chinese hamster cells by various chemical and physical agents. 19734684403
cytogenetic and mutagenic effects of ddt and dde in a chinese hamster cell line. 19734346226
unscheduled dna synthesis and repair replication in uv-irradiated chinese-hamster cells. 19734122930
the effect of inhibitors of rna and protein synthesis on dibutyryl cyclic amp mediated morphological transformations of chinese hamster ovary cells in vitro. 19734347524
[expression of tumorigenic potential in isologous hybrid clones of chinese hamster cells (author's transl)]. 19734790834
photoreactivation of ultraviolet-induced chromosomal aberrations.ultraviolet induces only chromatid-type aberrations in synchronized g(1) v-79 chinese hamster and a8w243 xenopus tissue culture cells. posttreatment with white light prevents expression of most potential aberrations in the a8 toad cell, which possesses a photoreactivation enzyme. we conclude that the major ultraviolet-induced dna lesion leading to chromosomal aberrations is the pyrimidine dimer.19734682133
determination of the cell cycle by microautoradiographic method in the cells of bone marrow in the chinese hamster in vivo. 19734805256
caffeine, caffeine derivatives and chromosomal aberrations. vi. the influence of temperature on the aberration-frequency induced during prophase and late g2 by 8-methoxycaffeine and 8-chlorocaffeine in chinese hamster cells. 19734798690
cell membrane permeability during the cell generation cycle in chinese hamster ovary cells. 19734797788
structuredness of the cytoplasmic matrix and michaelis-menten constants for the hydrolysis of fda during the cell cycle in chinese hamster ovary cells. 19734797787
the development of the diencephalon in the chinese hamster: an investigation into the validity of the criteria of subdivision of the brain. 19734755748
a quantitative analysis of colcemid-induced chromosomal nondisjunction in chinese hamster cells in vitro. 19734714918
[topographic anatomy of the thoracic cavity and neck in the chinese dwarf hamster (cricetulus griseus milne edwards 1867)]. 19734707943
the effect of x-rays on labelling pattern of m 1 and m 2 chromosomes in chinese hamster cells. 19734682596
stable telocentric chromosomes produced by centric fission in chinese hamster cells in vitro. 19734682090
the chromosomes of cho, an aneuploid chinese hamster cell line: g-band, c-band, and autoradiographic analyses. 19734120885
mutagenicity and carcinogenicity of n-methyl-n'-nitro-n-nitrosoguanidine i. induction of chromosome aberrations and mitotic anomalies in chinese hamster ovary cells.cultured chinese hamster ovary (cho) cells were exposed to different concentrations of n-methyl-n'-nitro-n-nitrosoguanidine (mnng) for either 24 hr or 6 days. for cytological consequences of mnng exposure, cho cells were treated for 24 hr and allowed a 24 hr recovery period prior to analysis; for the estimation of cytotoxicity of mnng, cells were treated for 6 days followed by a 6 day recovery period. the cytotoxic effect of mnng based on the colony-forming ability of treated cells showed a semi ...1973422929
isolation and characterization of revertants of the mammalian temperature sensitive leucyl-trna synthetase mutant tshl.nine spontaneous and seven ethyl methanesulfonate induced revertants of the chinese hamster ovary cell line mutant (tshl), which possesses a temperature sensitive leucyl-trna synthetase, were isolated and characterized with respect to growth rate, leucyl-trna synthetase activity and thermolability, intracellular leucine pool size, and rrna content. although most revertants had increased leucyl-trna synthetase activity, and of those tested, all but one had increased thermostability, each appears ...1973422661
nature of the iron requirement for chinese hamster v79 cells in tissue culture medium. 19734734766
relationship between the ratio of parental chromosomes and parental doubling times in chinese hamster-mouse somatic cell hybrids. 19734736587
surface antigens of mammalian cells as genetic markers. ii.a second surface antigen, b(l), lethal in the presence of specific antibody and complement has been identified on some human cells and shown to behave as a good genetic marker. it is autosomal, unlinked to the human a(l) antigen previously described, and unlinked to 15 other human genes. the a(l) antigen, which is linked to the lactic dehydrogenase a gene, is found on the hela, the cultured human fibroblast, and in small amounts on the human lymphocyte. b(l) occurs on hela cells, on cultured hum ...19734736830
independent loss of human hexosaminidases a and b in man-chinese hamster somatic cell hybrids. 19734737100
a cytological study of the karyotype of spleen cells from scrapie-affected chinese hamsters. 19734738622
caffeine inhibition of postreplication repair of n-acetoxy-2-acetylaminofluorene-damaged dna in chinese hamster cells. 19734741935
[the development of cell classes in the liver of rats and chinese hamsters (author's transl)]. 19734777261
comparative studies of organs in the european hamster (cricetus cricetus l.), the syrian golden hamster (mesocricetus auratus w.) and the chinese hamster (cricetulus griseus m.). 19734779674
cytological mapping of the genes assigned to the human a 1 chromosome by use of radiation-induced chromosome breakage in a human-chinese hamster hybrid cell line. 19734785162
cell-cycle-dependent variations of deoxyribonucleoside triphosphate pools in chinese hamster cells. 19734795783
effect of amino acid and serum deprivation on the regulation of rna synthesis in cultured chinese hamster ovary cells. 19734796172
a comparison of the interaction of chinese hamster fibroblasts with human and bovine transferrins, and conalbumin (chick-egg transferrin). 19734796207
asparagine-requiring tumor cell lines and their non-requiring variants: cytogenetics, biochemistry and population dynamics.asparagine-requiring jensen and walker rat tumor cells and their asparagine-independent variants have been analyzed. the following results were obtained: (1) both cell lines have very low levels of asparagine synthetase, and non-requiring revertants isolated from these lines have elevated levels of the enzyme. (2) no differences in chromosome number were detected between the parent jensen line and five jensen non-requiring revertants isolated from it. (3) both jensen and walker cells undergo asp ...19734798091
cellular reactions of o6-methylguanine, a product of some alkylating carcinogens.cultures of a purine-requiring mutant of chinese hamster ovary cells (cho-104b), randomly bred hamster embryo cells, or escherichia coli b(s-1) were treated with non-toxic doses of (3)h-labelled o(6)-methylguanine. dna and rna were isolated and subjected to enzymic digestion to nucleosides at ph8. the products of digestion were analysed by ion-exchange chromatography on columns of dowex 50 (nh(4) (+) form) at ph8.9. no (3)h-labelled o(6)-methylguanosine was detected in nucleic acid digests. (3)h ...19734590203
transfer of genetic information by purified metaphase chromosomes.transfer of genetic information from isolated mammalian chromosomes to recipient cells has been demonstrated. metaphase chromosomes isolated from chinese hamster fibroblasts were incubated with mouse a(9) cells containing a mutation at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus. cells were plated in a selective medium, resulting in death of all unaltered parental a(9) cells. however, colonies of cells containing hypoxanthine phosphoribosyl transferase (ec appeared ...19734515624
chromosomal interchanges induced by radiation in spermatogonial cells and leukocytes of mouse and chinese hamster. 19734515916
regional localization of loci for human pgm and 6pgd on human chromosome one by use of hybrids of chinese hamster-human somatic cells.the human gene loci phosphoglucomutase(1) (pgm(1), ec and 6-phosphogluconate dehydrogenase (6pgd, ec, which are located on human chromosome one, have been assigned to a specific region of the short arm of that chromosome, by use of a hybrid cell line derived from a chinese hamster cell line deficient in hypoxanthine phosphoribosyl transferase and a strain of human diploid fibroblasts. cytogenetic analysis of a hybrid clone maintained for about 50 generations in vitro revealed ...19734517931
identification of chick chromosomes in cell hybrids formed between chick erythrocytes and adenine-requiring mutants of chinese hamster cells.when chick erythrocytes were fused with adenine-requiring mutants of chinese hamster cells of two different complementation classes and grown in adenine-free medium for 1 week or longer, mitotic cells were observed containing both chick and chinese hamster metaphase chromosomes within a single cell. stable hybrid clones were subsequently isolated that possessed, in addition to a complete chinese hamster genome, a single specific chick chromosome. hybrids resulting from fusions involving differen ...19734517942
chromosome and chromatid exchanges in chinese hamster cells. 19734348023
the heterogeneous distribution of acid hydrolases within a homogeneous population of cultured mammalian cells.1. chinese-hamster ovary fibroblasts were cultured to provide a homogeneous cell population. homogenates obtained from these cells were fractionated by centrifugation techniques and the resulting fractions were analysed for protein and for enzymes representative of certain subcellular particles. 2. unlike those in rat liver homogenates, the mitochondrial and lysosomal populations proved impossible to separate by differential centrifugation owing to the similarity of their sedimentation propertie ...19734353380
expression of malignancy in interspecies chinese hamster x mouse cell hybrids. 19734355218
proline biosynthesis: multiple defects in chinese hamster ovary cells. 19734356052
microbial flora and viral contact status of chinese hamsters (cricetulus griseus). 19734357853
localization of genes on human chromosomes by studies of human-chinese hamster somatic cell hybrids. assignment of pgm3 to chromosome c6 and regional mapping of the pgd, pgm1 and pep-c genes on chromosome a1. 19734358963
a temperature-sensitive function in a chinese hamster line affecting dna synthesis. 19734359532
mutations affecting the structure of hypoxanthine: guanine phosphoribosyltransferase in cultured chinese hamster cells.14 clones resistant to 8-azaguanine, isolated from mutagenically treated cultured cells from chinese hamsters, were tested for loss of enzymic and immunological activities of hypoxanthine: guanine phosphoribosyltransferase. three of the clones had no enzymic activity but reacted strongly with antiserum prepared against the enzyme (crm(+)), indicating the presence of a defective enzyme protein, probably caused by a mutation in its structural gene. the other 11 mutants had little or no enzymic or ...19734119786
expression of endogenous rna c-type virus group-specific antigens in mammalian cells.highly sensitive and specific radioimmunoassays are described for quantitation of the intraspecies determinants of several mammalian c-type viral group-specific (gs) antigens. an interspecies (gs-3) immunoassay has been developed which has both the broad reactivity and great sensitivity necessary for detection of c-type viruses where intraspecies gs assays are not available. by using these immunoassays, the expression of endogenous virus-specified gs antigens in mammalian cells of different spec ...19734127032
[characterization of a hybrid cell line, "human leukemia-chinese hamster"]. 19734364713
isolation of replicating dna segments from chinese hamster cells by density equilibrium centrifugation. 19744281034
an "external" rna removable from mammalian cells by mild proteolysis.brief exposure of chinese hamster ovary cell monolayers prelabeled with [(32)p]phosphate and [(3)h]leucine to 1 mug/ml of trypsin under conditions in which cells remain fully viable causes the release of macromolecular (32)p and (3)h. whereas ribonuclease treatment was found to affect markedly both the (32)p and (3)h radioactivity, pronase treatment had little effect on the macromolecular (32)p. treatment of cells prelabeled with [(3)h]glucosamine and [(32)p]phosphate with insolubilized papain a ...19744531029
non-repairable strand breaks induced by 125i incorporated into mammalian dna.when (125)i is incorporated into chinese hamster dna (via (125)i-labeled iododeoxyuridine) and the cells are stored at 77 degrees k, the resulting decays of the isotope cause 4 to 5 breaks/single-strand per disintegration. on the average, about 50% of these breaks are repaired. in contrast, under the same conditions of storage and in the same range of total strand breaks/cell, 70-100% of the breaks induced by x-radiation are repaired. thus, the extreme toxicity of (125)i when incorporated into d ...19744531021
some biochemical properties of chinese hamster cells sensitive and resistant to actinomycin d.a graded series of drug-resistant chinese hamster sublines has been examined for biochemical changes accompanying resistance to actinomycin d. the most highly resistant subline, dc-3f/ad x, is maintained at 10 microg/ml of the antibiotic. it was shown that over 250 times more actinomycin d is required to inhibit rna synthesis in this subline than in the parental dc-3f line. the dc-3f/ad x subline was also shown to have a somewhat reduced capacity to transport uridine as compared to parental cell ...19744474176
the induction of ouabain-resistant mutants by n-methyl-n'-nitro-n-nitrosoguanidine in chinese hamster cells. 19744461312
chromosome aberrations in metaphase ii oocytes of chinese hamster (cricetulus griseus). i. the sensitivity of the pre-ovulatory phase to triaziquone. 19744437573
studies in the diabetic chinese hamster: light microscopy and autoradiography of pancreatic islets. 19744615023
purine mutants of mammalian cell lines. i. accumulation of formylglycinamide ribotide by purine mutants of chinese hamster ovary cells. 19744477717
dna-dependent rna polymerase activity of chinese hamster kidney cells sensitive to high concentrations of alpha-amanitin. 19744474058
selective enhancement of cytoplasmic protein species and continued histone synthesis during inhibition of dna synthesis in temperature-sensitive chinese hamster cells. 19744472590
cholesterol metabolism in the diabetic chinese hamster. 19744448326
streptozotocin-diabetes in the chinese hamster. long-term effects on the light microscopic structure of the pancreatic islet tissue, liver and kidney. 19744280870
aortic glucose metabolism in the diabetic chinese hamster. 19744217299
morphological characterization of membrane systems in a- and b-cells of the chinese hamster. 19744217292
the diabetic chinese hamster: in vitro insulin and glucagon release; the "chemical diabetic";; and the effect of diet on ketonuria. 19744217291
nuclear and cytoplasmic pools of deoxyribonucleoside triphosphates in chinese hamster ovary cells. 19744472692
effects of x-irradiation on dna precursor metabolism and deoxyribonucleoside triphosphate pools in chinese hamster cells. 197410881709
the effects of ionizing radiation on the kinetics of dna replication in synchronized chinese hamster ovary cells. 197410881700
ultrastructural changes in the nuclear envelope during mitosis of chinese hamster cells: a proposed mechanism of nuclear envelope reformation. 19744610163
letter: studies on the radiosensitizing effect of oxygen in chinese hamster cells. 19744548052
[a comparison between incorporation of the precursors of the a--t and g--c dna base pairs into the chromosomes of the chinese hamster]. 19744477721
sister chromatid exchanges induced in chinese hamster cells by uv irradiation of different stages of the cell cycle: the necessity for cells to pass through s. 19744473707
killing of chinese hamster cells in vitro by heating under hypoxic or aerobic conditions. 19744465105
chiasma in the xy bivalent of the chinese hamster. 19744371595
polyribosomal and particulate distribution of lysyl- and phenylalanyl-transfer ribonucleic acid synthetases.1. only two aminoacyl-trna synthetases from chinese hamster ovary cells are found associated with ribosomes and polyribosomes. 2. phenylalanyl-trna synthetase activity is found with the 60s subunit, 80s monoribosome and individual polyribosomes. an additional 15s form of the enzyme is also seen. 3. lysyl-trna synthetase activity is found in a form of about 20s and associated with ribosomal subunits and polyribosomes. the ribosomal subunits having lysyl-trna synthetase activity are about 6s large ...19744219282
letter: x-irradiation of mitotic chinese hamster cells. ii. evidence for cell-doublet survival response before karyo-and cytokinesis. 19744547759
the fate of pyrimidine dimers in the dna of ultraviolet-irradiated chinese hamster cells. 19744472368
temperature-sensitive mutants in populations of chinese hamster cells. 19744432118
effect of 239puo2 particle number and size on the frequency and distribution of chromosome aberrations in the liver of the chinese hamster. 19744428016
the effects of treatments with 5-(3,3-dimethyl-1-triazeno)imidazole-4-carboxamide in darkness and in light on survival and progression in chinese hamster ovary cells in vitro. 19744858377
dynamics of the ribosomal rna content and growth of synchronized chinese hamster cells. 19744433925
thermally enhanced radioresponse of cultured chinese hamster cells: damage and repair of single-stranded dna and a dna complex. 19744422045
studies on a chinese hamster line that is temperature sensitive for the commitment to dna synthesis. 19744367532
biosynthesis of biopterin by chinese hamster ovary (cho k1) cell culture. 19744210503
chinese hamster hypoxanthine-guanine phosphoribosyltransferase. purification, structural, and catalytic properties. 19744368495
characterization of a chinese hamster cell with a temperature-sensitive mutation in folate metabolism. 19744472030
an electron microscopy study of the effects on dibutyryl cyclic amp on chinese hamster ovary cells. 19744369770
sister chromatid exchanges induced by light flashes to 5-bromodeoxyuridine- and 5-iododeoxyuridine substituted chinese hamster chromosomes. 19744135474
banding and chromatid separation in chinese hamster chromosomes. 19744134900
thermal sensitivity and the effect of elevated temperatures on the radiation sensitivity of chinese hamster cells. 19744859562
comparative frequency of dominant and recessive markers for drug resistance in chinese hamster cells. 19744834409
enhancement of dna synthesis in a mammalian cell-free system by trypsin treatment.dna synthesis in a broken cellular preparation of chinese hamster cells was enhanced approximately 10-fold by a brief trypsin treatment. alphachymotrypsin also enhanced the synthesis, whereas pronase did not. the trypsin appears to be acting on a component of the nucleus. evidence suggests that the trypsin is not removing protein from the dna, but may be activating the system some other way.19744526218
insulin secretion of the isolated perfused pancreas of the chinese hamster (cricetulus griseus). 19744406592
studies on 1-beta-d-arabinofuranosyl-cytosine (ara-c) resistant mutants of chinese hamster fibroblasts. ii. high resistance to ara-c as a genetic marker for cellular hybridization. 19744366978
effect of quinacrine on survival and dna repair in x-irradiated chinese hamster cells. 19744856778
the frequency and distribution of isolabelling in chinese hamster chromosomes after exposure to x-rays. 19744836308
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