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281.
Summary A relatively safe and simple procedure was developed for the induction of hepatomas in the rat by the s.c. administration of powdered 3-methyl-p-dimethylaminoazobenzene. 相似文献
282.
Summary The effects of time and various doses of testosterone on the responsiveness of lactate dehydrogenase of pituitary of 7-, 38- and 78-week-old rats were studied. The activity of the enzyme increases in 78-week-old rats. Castration decreases the enzyme activity at all ages. Maximum increase in the enzyme activity is seen with 50 and 100 g of testosterone 4 h after administration of hormone to castrated rats. No further time and dose-dependent effect is observed. The magnitude of increase for the enzyme is higher at the age of 38 weeks and decreases in 78-week-old rats.To whom all correspondence should be addressed. The authors are grateful to Professor M.S. Kanungo, Biochemistry Laboratory, Department of Zoology, Banaras Hindu University for the suggestions and encouragement. K.V.G. thanks the PL-480 for a research fellowship. 相似文献
283.
M M Beljanski P Bourgarel M S Beljanski 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(24):1825-1828
Under well defined conditions ribosomal RNAs purified from Escherichia coli can be degraded by ribonuclease U2 giving rise to RNA fragments of 60--70 nucleotides. In vitro, these fragments are efficiently transcribed into a complementary DNA by DNA polymerase RNA dependent, partially purified from extracts of E. coli. In vivo, "RNA-fragments-U2" inhibit the development of plant tumors. 相似文献
284.
C Torrossian 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(9):693-696
The oxygen consumption of "hibernating" ants shows a grouping effect translated by a significant decrease in the level of oxygen consumption as a function of grouping effect. The general relation between oxygen consumption and the living body mass is the same, if the living material belongs to a single animal, or a social community of ants. 相似文献
285.
Triiodothyronine injected daily to pregnant rats for the last week of gestation (50 microgram/100 g b.wt) increased the specific activities of 5 acid glycosidases in the fetal forebrain and cerebellum. Cortisone (50 mg/100 g b.wt) administered in the same period had no effect on cerebellum acid hydrolases, but decreased their activity in the forebrain. 相似文献
286.
Daily administration of vitamin D3 (75,000 IU/kg b. wt) for 7 days accelerated Trichinella spiralis cyst calcification in rats with a 14-week-old infection. When disodium ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered (50 mg/kg b. wt) from 2 days before until 2 days after vitamin D3 treatment, cyst calcification was inhibited. Thus, the ability to inhibit E. spiralis calcification has demonstrated for the first time. 相似文献
287.
288.
The spontaneous conversion of mammalian cyclic GMP-dependent protein kinase (G-PK) into modulator-dependent protein kinase (type II) (M-PKII) in the absence of cGMP or histone was observed in vitro. The findings, together with similarity in substrate protein specificity, suggest that M-PKII is the catalytic subunit of mammalian G-PK. 相似文献
289.
At ambient temperatures (Ta) of both 8 and 22 degrees C, intraventricular administration of TRH (10-80 microgram) produced a dose-dependent hypothermia in rats. The hypothermia was due to both decreased metabolic heat production and cutaneous vasodilatation. In contrast, at 30 degrees C Ta, TRH increased metabolic heat production (due to behavioral excitation) and led to hyperthermia. 相似文献
290.
Summary Silver-staining has been used to identify the nucleolus organizer regions (NORs) in the bharal. These show homology with sheep, goat, cattle and aoudad. The association of the NORs on both telomeres of chromosome 3 results in a ring chromosome. 相似文献