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181.
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
182.
Lipoplysaccharide (endotoxin) from E. coli cells produced lethal effects in guinea-pigs. Endotoxin caused no visible dermal change in normal animals, but produced skin reactions characterized by specific Arthus-type (Type III immune hypersensitivity) vascular inflammation in immunized animals. It is concluded that Arthus allergic reactions were evoked by endotoxin, however, endotoxin lethal toxicity appears independent of this process. 相似文献
183.
A K Sayadi G Gaudin-Chazal N Seyfritz J J Puizillout 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(6):569-572
A minute amount of serotonin injected in the nodose ganglion circulation area develops abrupt myosis and general electrocortical synchronization activity in "encéphale isolé" Cat preparation. This hypnogenic effect of serotonin can still be reproduced after transection of vago-aortic nerves caudally to the nodose ganglia. The same injections become ineffective after rostral transection of the same pathway. These results suggest that serotonin may trigger some signs of sleep through peripheric nervous elements in which are probably localized in the nodose ganglia. 相似文献
184.
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
185.
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
186.
Summary Direct incorporation and cold trap experiments suggest that cholest-4-en-3-one is an intermediate in the conversion of cholesterol into 3-hydroxymethyl-A-nor-cholestane in the marine spongeAxinella verrucosa. Cholest-4-en-3-one is further transformed by the sponge into cholest-4-en-3-ol, 5-cholestan-3-one and 5-cholestan-3-ol; these compounds arise from side reactions, which are not part of the major metabolic route leading to 3-hydroxymethyl-A-norsteranes. 相似文献
187.
Summary The karyotype of the pampas fox has 2n=74 and a NF=76. Except forChrysocyon brachyurus, 2n=74 is a common diploid number for the South American Canidae. This number is higher than in theVulpes group and lower than in the group of the typicalCanis. No marker chromosomes are present in the South American Canidae. 相似文献
188.
D. V. Amin R. B. Doctor A. O. Girdhar U. H. Shah 《Cellular and molecular life sciences : CMLS》1980,36(12):1410-1411
Summary Prostaglandin (PG) release was measured from the isolated perfused rabbit heart. The effects of -adrenergic stimulation and blockade suggest that PG synthesis is regulated in part by adrenergic mechanisms. 相似文献
189.
Summary The concentrations of testosterone (T) and 5-dihydrotestosterone were measured in fluid collected from the rete testis of immature and adult rats. The results indicate that adult levels of T are attained in the seminiferous tubules much earlier than in the peripheral circulation.This work was performed at the Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts, USA and supported by the National Institutes of Health through grants HD12641 and HD12642. We thank Dr B.V. Caldwell for antiserum to testosterone. 相似文献
190.
H. Watanabe J. A. Menzies J. C. K. Loo 《Cellular and molecular life sciences : CMLS》1981,37(8):883-884
Summary Isonicotinic acid hydrazide (isoniazid) was shown to react readily with 17-ethinyl-17-hydroxyestr-4-en-3-one (norethindrone) to form the isonicotinyl hydrazone of the steroid under conditions likely to exist in the stomach. The hydrazone was detected in guinea-pig, but not rat, plasma following its oral administration. Rat liver tissue metabolized the compound more rapidly than guinea-pig liver in vitro which probably accounts for the failure to detect the hydrazone in rat plasma. 相似文献