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171.
Effects of cyproterone acetate, a synthetic steroidal compound, on the reproductive organs of female rats have been investigated. This agent caused reduction of ovarian weights indicative of suppression of pituitary gonadotrophins. Oestrogenic nature of cyproterone acetate was investigated in intact and ovariectomized rats taking uterine weight and vaginal keratinization as an index of oestrogenicity. Cyproterone acetate in ovariectomized animals induced vaginal keratinization and increased the uterine weights. These effects were parallel to the effect of oestradiol dipropionate in ovariectomized animals, thus indicating oestrogenic activity of cyproterone acetate. We may conclude that the above compound caused antifertility effects due to its oestrogenic nature at the dose level of 2 mg/alternate day in rats when the compound was administered subcutaneously. 相似文献
172.
P Jeyasingh C D Gupta A K Arora M L Ajmani 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1979,37(2):117-122
230 adult Indian tali (from Agra region) were studied for the incidence of squatting facets. Extension of medial articular facet was observed in all the cases. Medial extension of trochlea was observed in 37% of cases; lateral extension of trochlea in 71.6% of cases, lateral squatting facets in 43.5% of cases and medial squatting in 8.6% of cases. The present data are compared with that of other workers. 相似文献
173.
Goutam Gupta Manju Bansal V. Sasisekharan 《International journal of biological macromolecules》1980,2(6):368-380
Left handed duplexes are shown to be in agreement with the X-ray intensity data of A-, B- and D-forms of DNA. The structures are stereochemically satisfactory because they were obtained following a stereochemical guideline derived from theory and single crystal structure data of nucleic acid components. The same stereochemical guideline also led to right handed duplexes for B- and D-forms of DNA which have stereochemically preferred conformation and hence are superior to those given by Arnott and coworkers10,11. 相似文献
174.
A suspension ofPlasmodium berghei obtained by lysis with saponin of red blood cells from an infected rat showed high hemolytic activity, when incubatedin vitro with normal rat red blood cells. The hemolysis was a temperature-dependent process and was dependent on the concentration
of the parasite. Plasma ofPlasmodium berghei infected albino rats also possessed lytic activity. 相似文献
175.
Radhey S. Gupta 《Biochemical and biophysical research communications》1980,94(4):1303-1310
Stable mutants (Dipr), highly resistant to diphtheria toxin have been selected from a sensitive human lymphoblast line. A second human lymphoblast line, HH-4 (and its derivative TK6-1) were found to be highly resistant to diphtheria toxin without any previous selection, suggesting the presence of the Dipr allele in the human population. The resistance of protein synthesis in extracts of mutant cells to diphtheria toxin indicates that the genetic lesion in the resistant lines examined involved an alteration in the protein synthesis. In comparison to sensitive cells, the mutant cell extracts contained reduced (30–40%) levels of ADP-ribosylatable elongation factor-2 activity suggesting that the lesion presumably affects elongation factor-2 in such cells. The biochemical phenotype of these mutants appears similar to that of the DiprIIb class of mutants of Chinese hamster cells (4,6) which behave codominantly in hybrids. 相似文献
176.
Specific protein phosphorylation in interferon-treated uninfected and virus-infected mouse L929 cells: enhancement by double-stranded RNA. 总被引:1,自引:0,他引:1 下载免费PDF全文
S L Gupta 《Journal of virology》1979,29(1):301-311
The enhanced phosphorylation of specific protein(s) observed in extracts from interferon-treated cells (in the presence of ATP and double-stranded [ds] RNA) was also seen in intact mouse L929 cells upon treatment with dsRNA, polyriboinosinic.polyribocytidylic acid [poly(rI.rC)] or reovirus dsRNA, using 32Pi as radiolabel. Labeling of a 65,000-dalton protein(s) with 32P was greatly increased in interferon-treated cells in the presence of added dsRNA, suggesting that the expression in vivo of the kinase activity involved is regulated by dsRNA. This was used as a test system to investigate whether the activity of interferon-induced enzyme(s) is stimulated following virus infection, possibly owing to the accumulation of dsRNA. No obvious increase in 32P-labeling of 65,000-dalton protein(s) was observed upon infection of interferon-treated cells with mengovirus or vesicular stomatitis virus. A basal level of 32P-labeling of the 65,000-dalton protein(s) was detected in interferon-treated cells in the absence of added dsRNA, indicating a basal level of expression of the kinase activity involved. The possible implications of these results are discussed. 相似文献
177.
Clifford M. Renk Rishab K. Gupta Donald L. Morton 《Cancer immunology, immunotherapy : CII》1981,11(1):7-16
Summary Human tumor and normal cell lines in culture were examined for the release of factors capable of inhibiting lymphocyte blastogenesis. Supernatants from tumor cell cultures of melanoma, carcinoma (lung, colon, breast), sarcoma, and normal fibroblasts inhibited normal lymphocyte response to PHA. Only supernatants from the tumor cell lines C1 (colon carcinoma), 734B (breast carcinoma), and 231 (breast carcinoma) were found to inhibit both PHA and ConA responses significantly. The two breast carcinoma cell lines, 734B and 231, which also were capable of inhibiting lymphocyte responses to PPD and alloantigens, were investigated further. The inhibition of lymphocyte blastogenesis caused by the supernatant of these two cell lines could not be overcome by the addition of added mitogen. Further experiments showed that the inhibition was not due to nutrient deficiencies and the supernatants were not directly toxic to the lymphocyte cultures as judged by trypan blue exclusion. 相似文献
178.
V. Sasisekharan Goutam Gupta Manju Bansal 《International journal of biological macromolecules》1981,3(1):2-8
Based upon a stereochemical guideline, two topologically distinct types of helicalduplexes have been deduced for a polynucleotide duplex with alternating purine pyrimidine sequence (PAPP): (a) right-handed uniform (RU) helix and (b) left-handed zig-zag (LZ) helix. Both structures have trinucleoside diphosphate as the basic unit wherein the purine pyrimidine fragment has a different conformation from the pyrimidine-purine fragment. Thus, RU and LZ helices represent two different classes of sequence-dependent molecular conformations for PAPP. The conformationalf eatures of an RU helix of PAPP in B-form and three LZ-helices for B-, D- and Z-forms are discussed. 相似文献
179.
Summary Degeneration of testis has been observed after administration of Iodine-125 in potassiumperchlorate treated rats. Histological damage is associated with loss of DNA, RNA, acid phosphatase, total adenosine triphosphatase (ATPase) and Na/K dependent ATPase. Iodine-125 induced atrophic testis shows higher content of sodium and lower levels of potassium as compared to control testis. Damage of testis by Iodine-125 has been compared with atrophied testis, following gamma irradiation earlier reported. Auger effect due to Iodine-125 decay and transmutation at the sites of nuclei and plasma membrane of germinal cells seems to be the possible explanation for testicular damage caused by Iodine-125. 相似文献
180.