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131.
简要介绍了生物细胞色素P450分布的多样性、P450的功能、P450在不同领域的研究现状与进展。鉴于P450的研究无论在理论上探索生物的生理代谢、选择进化和生物与环境的关系方面,或在环境保护、农业生态、生物防治、作物基因工程和医药卫生等应用方面,都有广泛的实践意义,因此,应该受到更大的关注和重视。 相似文献
132.
The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited resource of new antitumor agents in the field of the development of marine bioactive substances. In this review, the progress on studies of antitumor peptides from marine sources is provided. The biological properties and mechanisms of action of different marine peptides are described; information about their molecular diversity is also presented. Novel peptides that induce apoptosis signal pathway, affect the tubulin-microtubule equilibrium and inhibit angiogenesis are presented in association with their pharmacological properties. It is intended to provide useful information for further research in the fields of marine antitumor peptides. 相似文献
133.
The metabolism of exogenous glucose-14C in the light and the dark was studied in the detached leaves of tomato plants grown with ammonium nitrogen and nitrate nitrogen. In the light, 14CO2, release and incorporation of glucose into insoluble materials were hardly affected at all by the nitrogen sources. Among the soluble labelled amino acids, serine had the greatest amount of label in the ammonium-plants while aspartate had the greatest amount in the nitrate-plants. This aspartate was synthesized from C3-compounds by carboxylation. During dark-light transition, the change in the composition of soluble amino acids was more rapid in the ammonium-plants than in the nitrate-plants. In the dark, 14CO2-release, which was ten times as much as in the light, was larger in the ammonium-plants than in the nitrate-plants; but the synthesis of high molecular compounds from glucose in the ammonium-plants was about half that in the nitrate-plants. So, it is considered that respiration operates sufficiently in the ammonium-plants. The effects of DCMU and a 100% O2 atmosphere on glucose metabolism in both groups of plants were studied and the respiration of leaves in the light was discussed. 相似文献
134.
对江苏和安徽地区患颤抖病的中华绒螯蟹(Eriocheir sinensis)各器官和组织进行光镜和电镜观察。结果表明,类立克次体(Richettsia-like Organisms,RLOs)广泛寄生于病蟹各器官和组织中。它们特异性地寄生于病蟹各器官的肌肉和结缔组织以及血细胞中,血淋巴中的小颗粒细胞是类立克次体的主要繁殖场所和传播载体。类立克次体对病蟹机体的结缔组织的广泛侵入,以及对胸神经节及神经与肌肉的接头-运动终板的侵染正是颤抖病症状(不食、肌无力、肢体阵发性颤抖)的病理结构基础。本研究旨在探讨RLOs与中华绒螯蟹颤抖病的关系,从而为建立有效的防治措施奠定理论基础。 相似文献
135.
我国水生生物多样性及其研究进展 总被引:1,自引:0,他引:1
生物多样性是地球上生命经历几十亿年发展进化的结果,是人类赖以生存的物质基础。广大科技工作者围绕生物多样性保护与可持续利用2大目标进行了一系列研究,取得一定进展。文章在综合论述国内水生生物多样性现状、利用与保护研究基础上,侧重对鱼类多样性研究技术手段、参与国际合作的渠道及保护措施进行了概述,同时分析了生物技术在重要水生生物多样性研究领域的应用前景。 相似文献
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138.
Not only physiological phenomena but also pathological phenomena can now be explained by the change of signal transduction in the cells of specific tissues. Commonly used cellular signal transductions are limited. They consist of the protein–tyrosine kinase dependent or independent Ras-ERK pathway, and the PI3K-Akt, JAK-STAT, SMAD, and NF-κB-activation pathways. In addition, biodegradation systems, such as the ubiquitin–proteasome pathway and autophagy, are also important for physiological and pathological conditions. If we can control signaling for each by a low-molecular-weight agent, it would be possible to treat diseases in new ways. At present, such cell signaling inhibitors are mainly looked for in plants, soil microorganisms, and the chemical library. The screening of bioactive metabolites from deep-sea organisms should be valuable because of the high incidence of finding novel compounds. Although it is still an emerging field, there are many successful examples, with new cell signaling inhibitors. In this review, we would like to explain the current view of the cell signaling systems important in diseases, and show the inhibitors found from deep-sea organisms, with their structures and biological activities. These inhibitors are possible candidates for anti-inflammatory agents, modulators of metabolic syndromes, antimicrobial agents, and anticancer agents. 相似文献
139.
根据设计对象所处地理位置和周围环境,在设计理念上打破传统的单位附属绿地以规则式为主的惯例而采用自然式,在功能要求、景观布局方面充分考虑实用性和观赏性,并将生态学理论和景观美学运用于植物景观设计中,进行甘肃省第四劳教所园林景观设计。
相似文献
140.
通过收集国内外现行标准、规范,以中国海洋领域现行标准体系为基础,研究以原子吸收法测定海洋生物体中Fe、Mn、Ni元素的标准方法。通过加入Cacl2消除火焰法测定Fe、Mn元素的干扰或加入Pd(NO3)2和Mg(NO3)2消除石墨炉法测定Mn、Ni元素的干扰;在特定温度以HNO3-H2O2常压消解或微波消解样品,Fe、Mn元素以火焰法测定、Mn、Ni元素以石墨炉法测定,实验结果表明Fe、Mn、Ni元素的溶出值均在标准值范围内,从而证明该方法具有可行性,适用于海洋生物体的标准方法。 相似文献