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101.
The functional role of 5-HT1 receptors in the memory trace retrieval was investigated in amygdala (AM), central gray substance of midbrain (CGS) and frontal cortex. There is used the passive avoidance response in the rat. The decrease of 5-HT1 binding sites in AM and CGS was revealed for the rats with retention of the passive avoidance response. The binding of 3H-5-HT in AM was found two sets of binding sites. It was concluded, that 5-HT1 receptors of AM and CGS are involved in learning processes either in the moment of the memory trace retrieval or immediately after it. 相似文献
102.
B Schneppe G Deckers-Hebestreit K Altendorf 《The Journal of biological chemistry》1990,265(1):389-395
The uncI gene, the first gene of the unc operon, has been cloned into an expression vector carrying the lambda PRPL promoters in tandem orientation and the gene cI857 coding for the thermolabile repressor. Linkage of the uncI gene to an efficient ribosome binding site (the translational initiation region of the uncE gene) resulted in 10-20-fold increased gene expression. The i protein has been extracted from overproducing cells using chloroform/methanol and purified to homogeneity by ion exchange chromatography. Analyzing the products of the uncI gene encoded by different plasmids, we provide evidence that, in contrast to the previously reported data (Walker, J. E., Saraste, M., and Gay, N. J. (1984) Biochim. Biophys. Acta 768, 164-200), the chromosome-encoded i protein contains the N-terminal sequence Ser-Val-Ser-Leu-Val-Ser-Arg and has a molecular weight of 13,504. 相似文献
103.
S B Seredenin I V Rybina T G Khlopushina V P Zherdev 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(11):491-493
Antipyrine oxidation was studied in C57BL/6 and BALB/c inbred mice. It was found that C57BL/6 are weak oxidant but BALB/c are strong oxidants of antipyrine. Animals F1 hybrids inherited the high capacity of antipyrine oxidation. 相似文献
104.
Sex-dependent effect of melatonin on the secretory activity of rat and hamster adrenal gland in vitro 总被引:1,自引:0,他引:1
Adrenal quarters from adult male or female hamsters were incubated in the presence of melatonin (10(-7) or 10(-4)M), and cortisol concentration in the incubation medium was assayed by RIA. Melatonin did not change cortisol output by adrenals obtained from the male hamsters, while a slight stimulatory effect was observed in female glands, the lower concentration of melatonin being more effective than the higher one. At both concentrations tested, melatonin notably stimulated corticosterone output by isolated rat adrenocortical cells derived from the males, and lowered corticosterone secretion by the cells obtained from the female glands only at a concentration of 10(-7) M. The lower concentration of melatonin increased ACTH (0.1 mU.ml-1)-stimulated corticosterone output by the cells of male and female rat adrenals. The pineal hormone was ineffective at a concentration of 10(-4) M, as well as in the presence of a higher dose of ACTH (1.0 mU.ml-1). These findings indicate a distinct sex-dependent effect of melatonin on in vitro cortisol and corticosterone production, and demonstrate that the modulatory effect of melatonin of the secretion of steroid hormones is more effective at lower concentrations. 相似文献
105.
Carbonic anhydrase (CA) activity in wheat leaves changed upon leaf dehydration: it decreased at mild stress (relative water
content, RWC, 81 %), but increased at severe water stress (RWC 74 %). Phosphoenopyruvate carboxylase activity was not significantly
affected by these stresses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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OBJECTIVE: To assess the relation of smoking and alcohol and coffee consumption to active Helicobacter pylori infection. DESIGN: Cross sectional study of patients attending a general practitioner. Active H pylori infection was measured by the 15C-urea breath test and detailed quantitative information on smoking and on alcohol and coffee consumption was obtained by a standardised self administered questionnaire. SETTING: One general practice in Germany. SUBJECTS: 447 patients aged 15-79 who had not had peptic ulcer disease or treatment for H pylori infection. MAIN OUTCOME MEASURES: Prevalence of H pylori infection according to smoking and alcohol and coffee consumption. RESULTS: Overall prevalence of infection was 21% (94/447). There was no significant relation between smoking and active H pylori infection. Alcohol consumption showed a negative dose-response relation and coffee consumption a positive dose-response relation with active infection. After adjustment for potential confounders, the odds ratios for patients who drank < or = 75 g and > 75 g of ethanol a week compared with non-drinkers were 0.90 (95% confidence interval 0.55 to 1.59) and 0.33 (0.16 to 0.68), respectively (P value for trend 0.005, assuming that 1 litre of beer and 0.51 of wine contain on average 50 g of ethanol in south Germany). Adjusted odds ratios for patients who drank < 3 cups and > or = 3 cups of coffee per day compared with those who did not drink coffee were 1.49 (0.71 to 3.12) and 2.49 (1.23 to 5.03), respectively (P value for trend 0.007). CONCLUSION: These results suggest a protective effect of alcohol consumption against active infection with H pylori and an opposite effect of coffee consumption. 相似文献