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871.
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Summary Serum thymic factor (FTS, zinc-free thymulin) protected mice from death after whole-body X-irradiation. It was significantly radioprotective even when administered after irradiation, but it was more effective when administered both before and after irradiation. The protective effect appears to be due to the enhancement of hematologic recovery in the animals.  相似文献   
875.
N-acyl dehydroalanines react with and scavenge mainly superoxide radical (O-2.) and hydroxyl radical (HO.). The ortho-methoxyphenylacetyl dehydroalanine derivative, indexed as AD-20, protects mice against damage resulting from total body X-irradiation, as measured by the increase in their survival time. AD-20 increases the LD50 at 30 days from 6.1 to 7.3 Gy in animals exposed to a wide range of X-rays (6 to 10 Gy). The dose reduction factor (D R F) of AD-20 is 1.20. We postulate that such radioprotective effect may result from its free radical scavenging activity.  相似文献   
876.
A series of microiontophoretic and VTA stimulation experiments, conducted in intact, GBR-12909-treated, alpha-methylparatyrosine-depleted or 6-hydroxydopamine-denervated rats, provide suggestive evidence for the existence of a presynaptic, positive feedback mechanism triggered by dopamine reuptake and favoring the release of this transmitter in the anterior cingulate cortex.  相似文献   
877.
Summary 1-O-Monoalkylglycerols with C12 to C20 chains were identified in the scent, gland secretions of the western diamondback rattlesnake (Crotalus atrox). This is the first documentation of these compounds in the skin secretions of a reptile.  相似文献   
878.
M G Tovey 《Experientia》1989,45(6):526-535
Specific interferon genes are transcribed at low levels in the spleen, liver, and peripheral blood leukocytes of normal individuals in the apparent absence of virus infection while other interferon genes remain unexpressed in the same tissues. In contrast, the genes of cytokines such as IL-1, IL-6 and TNF are expressed at relatively high levels in the organs of normal individuals. The level of expression of the IL-1, IL-6 and TNF genes is markedly reduced in the livers of patients with autoimmune liver disease compared to the level of expression in the liver of normal individuals, whereas the expression of interferon genes is similar in both normal and diseased liver, suggesting that a defect in the expression of specific cytokines is associated with severe liver disease.  相似文献   
879.
Chemistry of male dominance in the house mouse, Mus domesticus   总被引:1,自引:0,他引:1  
M Novotny  S Harvey  B Jemiolo 《Experientia》1990,46(1):109-113
Two terpenic constituents, E,E,-alpha-farnesene and E-beta-farnesene, were found to be elevated in dominant male urine when compared to subordinate or control males. These two urinary compounds were absent in the bladder urine of males; however, they were the most prominent constituents of the perputial gland's aliquots. The results of a two-choice preference test, conducted on ICR/Alb subordinate males, gave a strong indication that these two terpenic constituents introduced into the previously attractive stimulus significantly discouraged prolonged investigations by male mice. The compounds, whether present in the urine matrix or water, rendered the stimulus with a quality behaviorally similar to the urine of dominant males. It appears that they may be synonymous with the previously described aversion signal produced by dominant males. We suggest that these compounds may play a wide-ranging role in the territorial marking behavior of male mice.  相似文献   
880.
Inhibitory effects on fertilization of the ascidian of three benzyloxycarbonyl(Z)-aminoacyl prolinals and Z-Gly-Pro-chloromethyl ketone added before and after insemination were examined. The results suggest that the prolyl endopeptidase is involved in the process of fertilization, especially in a process taking place between chorion elevation and cell cleavage.  相似文献   
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