低分子量肝素钠的制备与临床应用

低分子肝素有抗凝血、抗血栓、调血脂、抗肿瘤等作用,与普通肝素相比具有皮下注射吸收好、半衰期长、生物利用率高,与血浆、血小板亲和力小、出血副作用少等优点.对低分子肝素的制备、质量检测和临床应用的研究进展进行了综述.     

近三年环烯醚萜类新化合物的研究进展

环烯醚萜类化合物是一类具有镇静、止痛、抗氧化、抗肿瘤等多种生理活性的天然活性分子。本文以环烯醚萜类化合物的母核结构特征进行分类,对近三年为主文献报导的新环烯醚萜类化合物进行了综述。     

植物激素检测技术研究进展

植物激素是植物体内合成的一系列痕量有机化合物,它们在植物的生长发育和环境应答过程中具有非常重要的作用,其超微定量及原位测定技术仍是制约植物激素研究的瓶颈问题之一。该文着重介绍了近年来茉莉酸及其甲酯、脱落酸、生长素、赤霉素和多肽激素等植物激素分析检测技术的最新研究进展,并对植物激素超微量、高灵敏检测技术研究中存在的问题和发展前景进行了简要的讨论。     

铁线莲属植物分类学及园艺学研究进展

从分类地位、引种育种、繁殖栽培和资源开发等方面,对铁线莲属植物的研究现状进行了较为系统的综述,并对其野生资源的合理利用和保护提出了一些建议,为今后进一步的研究工作提供参考。今后我国应在保护种质资源的基础上,加强铁线莲新品种的培育,尽快实现产业化生产。     

Detection of competitive enzyme inhibition with end point progress curve data

A model for a dimensionless factor, the inhibition detection limit (IDL), which describes the limit of detection of competitive inhibition for end point assays as a function of the proportion of substrate converted into product, has been developed. For a given end point enzymatic assay, the IDL function has a maximum that is dependent on the error structure parameters (four parameters) of the assay, the value of [S]o/K(ms), and the extent of product inhibition (K(ms)/K(mp)). Accordingly, the substrate conversion level that maximized the ability to detect samples with high Ki/[I] ratios was predicted for each member of a population of simulated assays. Furthermore, we identified a consensus substrate conversion level where the probability of a near-optimal robustness and detection limit for all the members of the assay population is maximal. Unlike the optimal substrate conversion level for individual assays, this consensus substrate conversion level was dependent only on [S]o/K(m), K(ms)/K(mp), and whether the signal increases or decreases during the course of the reaction. Consensus substrate conversion levels were beyond the initial velocity range for almost all the analyzed assay populations. It was shown that the IDL factor was a more informative indicator of assay quality than the popular Z' factor.     

毛翅目化石研究进展

本文详细总结和回顾了世界毛翅目化石研究简史,列出已发表的化石种类名录、分布及年代,共37科、193属、661种(包括中国发现的4科9属15种),描述了不同地质时期主要毛翅目化石的分类单元和分布地区。简要介绍了毛翅目分类系统及系统发育、不同地质时期毛翅目化石的产地及时代。初步分析了目前该类群所存在的一些问题,并对今后的研究工作进行了展望。     

Solar radiation decreases parasitism in Daphnia

Climate change and variation in atmospheric ozone are influencing the intensity of ultraviolet radiation (UVR) reaching ecosystems. Changing UVR regimes, in turn, may alter epidemics of infectious disease. This possibility hinges on the sensitivity of epidemiologically relevant traits of host and parasite to UVR. We address this issue using a planktonic system (a zooplankton host, Daphnia dentifera, and its virulent fungal parasite, Metschnikowia bicuspidata). Controlled laboratory experiments, coupled with in situ field incubations of spores, revealed that quite low levels of UVR (as well as longer wavelength light) sharply reduced the infectivity of fungal spores but did not affect host susceptibility to infection. The parasite's sensitivity to solar radiation may underlie patterns in a lake survey: higher penetration of solar radiation into lakes correlated with smaller epidemics that started later in autumn (as incident sunlight declined). Thus, solar radiation, by diminishing infectivity of the parasite, may potently reduce disease.     

石灰岩特有植物圆叶乌桕叶表皮形态特征及其生态适应性研究

采用扫描电子显微镜和光学显微镜,对石灰岩特有植物圆叶乌桕与同属的乌桕、山乌桕的叶表皮微形态进行观察,比较3个种的叶表皮形态特征,分析圆叶乌桕在石灰岩地区生长的环境适应特点。结果表明:圆叶乌桕叶下表皮细胞小且呈无规则型,细胞排列紧密;气孔集中分布于下表皮,气孔密度和气孔指数相对最小;气孔类型是无规则型,无副卫细胞;圆叶乌桕上下叶表皮有厚角质层和蜡质层,蜡被呈片状和网状。圆叶乌桕的叶表皮微形态特征反映了它对石灰岩生境的适应性较强。     

异嗜性小鼠白血病病毒相关病毒研究现状及展望

异嗜性小鼠白血病病毒相关病毒(XMRV)是第一个能够感染人类的γ逆转录病毒,该病毒最早在前列腺癌患者体内被发现。越来越多的研究提示,XMRV可能与前列腺癌和慢性疲劳综合征密切相关。我们就已知的XMRV的生物学特征、流行病学特征及研究展望做简要综述。     

进展性卒中血同型半胱氨酸变化的相关研究

目的:了解各型SIP患者Hcy浓度改变特点的同时,更深一层地探讨各型进展性卒中病情变化与血Hcy水平的关系.方法:抽取SIP组、SIS组脑卒中患者各50名,发病第1,2,3天清晨空腹肘静脉血5mL,采用全自动快速分析仪及其配套Hcy试剂盒,用荧光偏振免疫法测定血浆总Hcy水平.结果:不论是进展性脑卒中还是稳定性脑卒中,与正常相比,Hcy的水平要高于正常组,差异具有显著性,P＜0.01;同时进展性脑卒中与稳定性脑卒中相比较而言,进展性脑卒中的Hcy水平显著高于稳定性脑卒中,P＜0.05.结论:SIP患者Hcy水平显著高于稳定性脑卒中,Hcy增高可能是SIP发展的一个标志.