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关键词： 三价铬   生物学功能   机体代谢   缺乏   毒性  

摘要： 三价铬(Cr3+)是机体正常葡萄糖代谢所必需的微量元素。文章综述了Cr3+在动物体内吸收和代谢过程,以及通过增强胰岛素敏感性和葡萄糖耐受性发挥生物学功能的机制,并在此基础上介绍了Cr3+调节葡萄糖、脂质、蛋白质和核酸代谢的研究进展,Cr3+的缺乏及其毒性,以期为现代畜牧生产中科学应用Cr3+添加剂提供参考。

关键词： 黄河兰州段   大型底栖动物   群落结构   水质评价  

摘要： 本研究共从黄河兰州段抚河桥、湟水桥、新城桥、中山桥、包兰桥五个断面收集底栖动物2123头,分别隶属于1门10纲12目32科3属(种)。其中水生昆虫17属(种),环节动物7属(种),软体动物7属(种),扁形动物7属(种)和线性动物7属(种)。利用生物学污染指数(BPI)和Chandler生物指数(CBI),对春季和秋季黄河兰州段五个断面的水质分别进行了生物学评价,其中,春季湟水桥断面受污染最严重,呈现中污染,秋季湟水桥断面和春季、秋季其余各断面均呈现轻-中污染的趋势。说明底栖动物作为黄河兰州段水质监测评价的指标是可行的,通过对底栖动物群落结构的监测分析,有效弥补了物理和化学监测的不足,使得生物学指标与理化指标有机结合,二者相辅相成、相互补充,综合得出水质污染的程度和状况,进而反映更加真实的水体污染情况。

关键词： 壳糖胺微量元素螯合盐   生物学功能   动物生产  

摘要： 壳糖胺微量元素螯合盐是由脱乙酰壳聚糖(Chitosan,CTS)与微量元素金属离子(Zn、Cu、稀土等)进行配位反应而生成的具有环状结构的络合物。文章综述了壳糖胺微量元素螯合盐的理化性质、生物学功能及在动物生产中的应用,旨在为壳糖胺微量元素螯合盐作为新型饲料添加剂在动物生产中的应用提供参考。

关键词： biostratigraphy   deep-water benthic foraminifers   Paleocene   Eocene   North Pacific regions  

摘要： A zonal scheme for the Lower Paleogene of the northern Pacific Ocean is proposed on the basis of the stratigraphic distribution of benthic foraminifers in the lower bathyal-abyssal beds studied in boreholes in the North and South Pacific regions. This scheme includes eight subdivisions (six zones and two subzones). The boundaries of the benthic zonal subdivisions are defined by bioevents (appearance or disappearance of stratigraphically important taxa) and are linked to the zonal scales based on planktonic foraminifers and cal-careous nannoplankton. It is established that most of these bioevents are recognized subglobally. Apart from the evolutionary events, changes in the deep-water benthic foraminiferal assemblages were caused by changes in the paleooceanological environment. This allowed detailed characterization of a global mass extinction of assemblages of deep-water benthic foraminifers in the region studied. It is also established that changes in the assemblages of deep-water benthic foraminifers, observed in either change in their taxonomic composition or changes in abundance and diversity, resulted from the presence of different deep-water masses in the region.

关键词： INSECT flight   BATS  

摘要： An introduction to the special issue of the journal is presented which includes information on papers from a symposium entitled 'Advances in animal flight studies' which has perspectives on biology of flight of insects, pterosaurs and bats and mentions information of the editor of the issue.

关键词： Testis   Spermatogenesis   Non-receptor tyrosine kinase   Cell junction  

摘要： Src kinases are non-receptor tyrosine kinases that phosphorylate diverse substrates, which control processes such as cell proliferation, differentiation and survival;cell adhesion;and cell motility. c-Src, the prototypical member of this protein family, is widely expressed by several organs that include the testis. In the seminiferous epithelium of the adult rat testis, c-Src is highest at the tubule lumen during the release of mature spermatids. Other studies show that testosterone regulates spermatid adhesion to Sertoli cells via c-Src, indicating Src phosphorylates key substrates that prompt the disassembly of Sertoli cell spermatid junctions. A more recent in vitro study reveals that c-Src participates in the internalization of proteins that constitute the blood testis barrier, which is present between Sertoli cells, suggesting a similar mechanism of junction disassembly is at play during spermiation. In this review, we discuss recent findings on c-Src, with an emphasis on its role in spermatogenesis in the mammalian testis. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

关键词： SPERMATOZOA   LIPIDS   MAMMALS   COMPUTATIONAL biology   MALE reproductive organs  

摘要： To become fully fertile, mammalian spermatozoa must undergo a complex process of biochemical maturation within the female genital tract, which determines a marked lipid remodeling (LR) of membranes. Here, we represent this process as a biological network, which is a graph constituted by nodes (the molecules involved in LR) and by edges (their interactions). As a result, we found that LR network has a scale-free and small world topology. This implies that it is robust against random damage and that it allows a fast and specific transmission of information. In addition, the hubs in the network allow identification of the control mechanisms involved in membrane-related signaling, which could concur in determining the fate of ejaculated spermatozoa. Interestingly, different pathways involved in LR (maintenance of functional incompetence, reaching of fertilizing ability, apoptosis) are overlapped and some molecules take part in different signalling cascades;thus their role in sperm biology needs to be interpreted in a more large context. In addition, it was possible to differentiate, either based on their topological and biological characteristics, the molecules acting as global or local controller in LR. These findings may contribute to the understanding of capacitation-related signaling and of sperm physiopathology.

关键词： circadian rhythm   systems biology   genomics   transcriptomics   proteomics  

摘要： Systems biology, which can be defined as integrative biology, comprises multistage processes that can be used to understand components of complex biological systems of living organisms and provides hierarchical information to decoding life. Using systems biology approaches such as genomics, transcriptomics and proteomics, it is now possible to delineate more complicated interactions between circadian control systems and diseases. The circadian rhythm is a multiscale phenomenon existing within the body that influences numerous physiological activities such as changes in gene expression, protein turnover, metabolism and human behavior. In this review, we describe the relationships between the circadian control system and its related genes or proteins, and circadian rhythm disorders in systems biology studies. To maintain and modulate circadian oscillation, cells possess elaborative feedback loops composed of circadian core proteins that regulate the expression of other genes through their transcriptional activities. The disruption of these rhythms has been reported to be associated with diseases such as arrhythmia, obesity, insulin resistance, carcinogenesis and disruptions in natural oscillations in the control of cell growth. This review demonstrates that lifestyle is considered as a fundamental factor that modifies circadian rhythm, and the development of dysfunctions and diseases could be regulated by an underlying expression network with multiple circadian-associated signals.

关键词： 艾蒿   动物   生产性能   免疫功能   抗氧化功能  

摘要： 艾蒿作为中草药添加剂的一种,不仅可预防疾病,增强畜禽体质,而且还可促进血液循环,增强机体代谢,提高饲料转化率及生产性能。综述艾蒿作为绿色饲料添加剂的安全性及其对动物生产性能、血液生理生化指标、免疫和抗氧化功能的影响,为其在动物生产中的研究和应用提供参考依据。

关键词： 人非小细胞肺癌   生物学特性   动物模型   严重联合免疫缺陷   实验动物   常染色体隐性   无特定病原体   许可证号  

摘要： 我们采用不同方法，将具有高转移潜能的非小细胞肺癌细胞接种到实验动物肺组织，观察不同方法建立人非小细胞肺癌原位动物模型的生物学特性。 一、材料与方法 1．材料：实验动物购自北京维通利华公司。5～6周龄雄性严重联合免疫缺陷（SCIO）Beige小鼠（CB17．B6-PrkdcscidLystbg／CrlVr），Scid和Beige常染色体隐性突变同类系，T、B淋巴细胞功能缺失，自然杀伤（NK）细胞功能低下，许可证号SCXK（京）2011-0011，合格证号0250000。5～6周龄雄性裸大鼠（Vr：NIH-Foxnlmu），缺乏胸腺和T细胞，许可证号SCXK（京）2012-0001，合格证号0291126。无特定病原体（SPF）级环境中饲养实验动物，按昆明医科大学实验动物伦理委员会要求进行实验。人非小细胞肺癌细胞株H460SM由加拿大多伦多大学Ming-Sound Tsao惠赠。