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21.
C. Gianoulakis 《Cellular and molecular life sciences : CMLS》1989,45(5):428-435
Summary Alcoholism and alcohol abuse are serious health problems. Alcohol is known to influence the activity of a number of biological systems, for example the hormonal and neuronal systems. One of the biological systems whose activity is greatly influenced by alcohol is the endogenous opiate system. Alcohol modifies the function of both opiate receptors and opioid peptides. In fact it has been proposed that many of the effects of ethanol are mediated by its effects on the endogenous opiate system. This review will present results from various laboratories on the effects of acute and chronic ethanol treatments on various species, and on the release, biosynthesis and post-translational processing of the endorphins, enkephalins and dynorphins, the three known families of endogenous opioid peptides. Furthermore, the effect of acute and chronic ethanol consumption on the -endorphin system in man, and the possible implications of the functional activity of the endogenous opiate system for the genetic predisposition to alcoholism will be discussed. 相似文献
22.
H. J. Bestmann J. Erler O. Vostrowsky 《Cellular and molecular life sciences : CMLS》1988,44(9):797-799
Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.13. 相似文献
23.
J. Lukanov E. Milieva G. Russev B. Trifonov 《Cellular and molecular life sciences : CMLS》1985,41(1):68-70
Summary Follow-up investigation of the blood sera from preparturient women and women with habitual, abortions showed the presence of a factor which has an activating effect on smooth muscle preparations because it causes the release of prostaglandins. Gel-chromatographic counter flow separation and microelectrophoresis of the blood sera have shown that the isolated serum factor is a water soluble glycopeptide with a molecular weight of about 2000. 相似文献
24.
S. S. Tobe R. P. Ruegg B. A. Stay F. C. Baker C. A. Miller D. A. Schooley 《Cellular and molecular life sciences : CMLS》1985,41(8):1028-1034
Summary Titres of juvenile hormone (JH) have been determined in both hemolymph and whole body extracts of femaleDiploptera punctata during the first gonotrophic cycle using a method employing gas chromatography/mass spectrometry for qualitative and quantitative analysis. JH III is the sole JH found in both adult and last instarD. punctata. Maximum values of 1500 ng/ml (6M) were observed at the middle of the gonotrophic cycle, when basal oocyte growth rate was greatest. Changes in rates of JH release in vitro by corpora allata paralleled closely the changes in JH titre, suggesting that biosynthesis is a major regulator of titre. JH levels per animal were calculated from observed JH titres, and at certain time points in the gonotrophic cycle JH levels obtained from analysis of whole bodies were significantly greater than those predicted from hemolymph titres. These results suggest the existence of a nonhemolymph JH pool inD. punctata. Decay in JH titre after allatectomy of 5 day females has also been studied. Following a rapid initial decline, the rate of decay slowed appreciably 4 h post-operation. Thus, use of a first-order rate constant to estimate half-life of JH significantly underestimated the longevity of the hormone. The apparent persistence of JH following allatectomy may be due to the existence of a nonhemolymph JH pool. 相似文献
25.
A. Rakovska K. Milenov P. Henklein 《Cellular and molecular life sciences : CMLS》1990,46(10):1037-1041
Summary Suc-Tyr-(SE)-Met-Gly-Trp-Met-Asp--phenethylamide (GE 410) competitively antagonized the contractions of smooth muscle strips from guinea pig ileum (pA2=7.6, n=0.95) induced by cholecystokinin-octapeptide (CCK8). GE 410 inhibited the electrically-induced cholinergically mediated contractile responses and the [3H]ACh release in the ileum, as well as the CCK-stimulated electrical contractile responses and the [3H]ACh release in the cholinergic nerve terminals. The results suggest the existence of CCK-receptors not only in the smooth muscles but also on the neurons. 相似文献
26.
从受重油和焦化废水污染的水及土壤中分离出产鼠李糖脂的假单胞菌(Pseudomonas)12株,发现其菌群分布、糖脂产量与特定污染环境有一定相关性,产糖脂量较高的假单胞菌群是该污染环境中的优势降解菌. 相似文献
27.
双频辐照的声化学产额及其频率效应的研究 总被引:10,自引:1,他引:9
用碘释放法首次研究了28kHz分别与0.87MHz,1.06MHz,1.7MHz组成的双频超声辐照的声化学效应,结果表明,双频辐照增强的声化学产额存在着明显的频率效应。 相似文献
28.
Ecological long-term effects of cultigens becoming feral and of naturalization of non-native species
Transgenic cultigens may become feral as we know of some non-transgenic cultigens. The article explains two basic ways how cultigens become feral: through hybridization with a closely related wild plant and through revert to the wild-type. A long list of examples of cultigens becoming feral in Central Europe is presented. The process of becoming feral is compared to the naturalization of non-native species (Exotic Species Model). Ecological long-term effects of both cultigens becoming feral and non-native species being naturalized are discussed with special regard to the predictability of such events. The ecological aspects discussed in the article are as significant for transgenic cultigens as for non-transgenic cultigens. 相似文献
29.
经对六安市交通大厦的监测表明,装修会引起室内空气中氨和苯系物浓度升高。而比较简便的控制办法是:选用质 量较好的石材便有可能使氡含量达标;注意改善通风条件也可在一个多月的时间里使室内氨、甲醛、苯、甲苯、二甲苯的含量达 标。 相似文献
30.
廖华 《五邑大学学报(自然科学版)》2005,19(1):73-78
对拆船行业的发展现状作了介绍,对拆船生产工艺流程进行了阐述,重点分析了拆船生产过程中产生废水、废气和固体废弃物等的污染情况,并提出了拆船事故排油的处理方法以及拆船生产的有关环保措施. 相似文献