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1.
遗传资源获取与惠益分享:背景、进展与挑战   总被引:15,自引:1,他引:14       下载免费PDF全文
薛达元 《生物多样性》2007,15(5):563-568
本文回顾了《生物多样性公约》(CBD)有关遗传资源获取与惠益分享(access and benefit sharing,ABS)问题的谈判背景,介绍了ABS问题特设工作组的工作历程。对《公约》第8次缔约方大会以来有关ABS问题的谈判进展进行了详细的分析,特别是有关遗传资源来源证书制度的讨论与成果,进而对当前ABS问题面临的挑战进行了分析研究,包括国际层面上WTO体系和世界知识产权组织(WIPO)体系与CBD之间在遗传资源及相关传统知识在知识产权问题上的冲突,国家层面上ABS问题的立法需求与焦点问题,以及在确定遗传资源来源和实施惠益分享方面的技术限制等。  相似文献
2.
《生物多样性公约》国际履约的进展与趋势   总被引:6,自引:0,他引:6       下载免费PDF全文
张丽荣  成文娟  薛达元 《生态学报》2009,29(10):5636-5643
<生物多样性公约>履约15a来,在国际履约层次上已形成由缔约方大会、科技咨询附属机构会议、特设工家组会议以及技术专家组会议等构成的会议制度与履约机制.<公约>以生态系统方式为指导,制定了7个生态系统类型的专题工作方案;提出10个跨领域议题的准则及其主要目标和原则;并通过"战略计划",提出到2010年大幅度降低全球、地区和各国生物多样性锐减速度的战略目标.而在<公约>的国际谈判过程中,缔约方形成了不同的利益集团.2008年5月召开的第九次缔约方大会,在遗传资源获取和惠益分享、应对气候变化、构建海洋保护区体系等方面取得进展;并进一步提出未来在国际层面的履约需要集中资源,具体实施已经制定的计划和工作方案.  相似文献
3.
木聚糖是植物细胞壁的主要组分,它是木糖以β1 ,4 木糖苷键形成主链,乙酰基,阿拉伯糖基等为附链组成的复合多聚糖.木聚糖酶可以降解木聚糖主链,在木聚糖的生物降解中起着非常重要的作用[1 ] .根据木聚糖酶催化域(catalyticdomain ,CD)氨基酸序列的相似性,木聚糖酶可分为两个家  相似文献
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5.
This review focuses on matrix metalloproteinases (MMPs)-2 (gelatinase A) and -9 (gelatinase B), both of which are cancer-associated, secreted, zinc-dependent endopeptidases. Gelatinases cleave many different targets (extracellular matrix, cytokines, growth factors, chemokines and cytokine/growth factor receptors) that in turn regulate key signaling pathways in cell growth, migration, invasion, inflammation and angiogenesis. Interactions with cell surface integral membrane proteins (CD44, αVβ/αβ1/αβ2 integrins and Ku protein) can occur through the gelatinases' active site or hemopexin-like C-terminal domain. This review evaluates the recent literature on the non-enzymatic, signal transduction roles of surface-bound gelatinases and their subsequent effects on cell survival, migration and angiogenesis. Gelatinases have long been drug targets. The current status of gelatinase inhibitors as anticancer agents and their failure in the clinic is discussed in light of these new data on the gelatinases' roles as cell surface transducers — data that may lead to the design and development of novel, gelatinase-targeting inhibitors.  相似文献
6.
成功  王程  薛达元 《生物多样性》2012,20(4):505-511
传统知识是多个国际政府间组织的重要议题,各个组织开展了一系列讨论,形成了相关报告和决议,反映了不同的利益诉求,也表达了对于传统知识的不同见解和立场。在国际政府间组织中,以《生物多样性公约》为代表的国际组织关注环境与生物;以世界知识产权组织和世界贸易组织为代表的国际组织关注经济与贸易;以《土著人民权利宣言》为代表的国际组织关注社会和权利。结合我国在国际政府间组织中的已有承诺,以及丰富多样的传统知识等具体国情,建议我国需要更重视传统知识保护,并采取惠益分享的立法行动,制定以《名古屋议定书》为基础的传统知识保护制度和惠益分享制度,以期达成环境、经济和社会的协调发展。  相似文献
7.
《名古屋议定书》的主要内容及其潜在影响   总被引:1,自引:0,他引:1  
<生物多样性公约>第10次缔约方大会(2010年10月,日本名古屋)通过了<名古屋议定书>,这为全面实现<生物多样性公约>的三大目标,特别是第三项目标(公平公正地分享因利用遗传资源所产生的惠益)迈出了关键一步.建立遗传资源及相关传统知识获取与惠益分享(ABS)国际制度是<生物多样性公约>过去10年来的一项主要任务,<公约>缔约方大会于2000年专门建立了"ABS工作组",致力于该ABS国际制度的谈判.自2001年在德国波恩召开ABS工作组第1次会议到<名古屋议定书>达成,一共召开了9次工作组会议,其中第9次工作组会议召开了3次续会.<名古屋议定书>的主要内容包括:议定书目标;适用范围;获取遗传资源及相关传统知识的要求(事先知情同意程序);"共同商定条件"下公平分享因利用遗传资源和相关传统知识所产生的惠益;确保遵约的措施,包括披露遗传资源来源与原产地,遗传资源合法来源证书和监测遵约的检查点;能力建设等.谈判中最为核心的问题是遗传资源的定义是否包括衍生物,以及采取何种措施监测遗传资源的利用.因分歧太大,议定书文本未能规定在申请专利时强制性披露遗传资源来源及原产地,对建立遵约的监测检查点也未严格要求,在处理收集保存库中遗传资源的获取与惠益分享方面也不太明确.中国是全球生物多样性最为丰富的国家之一,是遗传资源重要提供国.<名古屋议定书>的通过和实施将对加强中国生物遗传资源的保护及促进其公平惠益分享具有重要意义.中国需要加强国家层次的立法,以配合议定书的实施.  相似文献
8.
Uroporphyrinogen decarboxylase (URO-D; EC 4.1.1.37), the fifth enzyme of the heme biosynthetic pathway, is required for the production of heme, vitamin B12, siroheme, and chlorophyll precursors. URO-D catalyzes the sequential decarboxylation of four acetate side chains in the pyrrole groups of uroporphyrinogen to produce coproporphyrinogen. URO-D is a stable homodimer, with the active-site clefts of the two subunits adjacent to each other. It has been hypothesized that the two catalytic centers interact functionally, perhaps by shuttling of reaction intermediates between subunits. We tested this hypothesis by construction of a single-chain protein (single-chain URO-D) in which the two subunits were connected by a flexible linker. The crystal structure of this protein was shown to be superimposable with wild-type activity and to have comparable catalytic activity. Mutations that impaired one or the other of the two active sites of single-chain URO-D resulted in approximately half of wild-type activity. The distributions of reaction intermediates were the same for mutant and wild-type sequences and were unaltered in a competition experiment using I and III isomer substrates. These observations indicate that communication between active sites is not required for enzyme function and suggest that the dimeric structure of URO-D is required to achieve conformational stability and to create a large active-site cleft.  相似文献
9.
There is an urgent need to develop simple and inexpensive methods for monitoring wildlife populations in resource-poor countries. List-based methods have been advocated as simple yet potentially useful biodiversity monitoring tools, and systems have recently been launched in a number of countries to collect species lists. We attempt to advance the use of systematic list-based monitoring by (1) suggesting improvements to the way in which list reporting rates are calculated; (2) assessing the extent to which degrading effort-corrected measures of abundance into simple species lists results in loss of information on population trends; (3) comparing long-term trends in list reporting rates with population trends from a wholly independent monitoring scheme. Daily species lists of birds were derived from regular trapping at a nature reserve in southern England. Most species showed a strong correlation across years between the proportion of lists on which they occurred, adjusted for list length (adjusted list reporting rate; ALRR), and an effort-corrected measure of abundance (captures per unit effort; CPUE). ALRR revealed almost as much about annual variation in abundance as CPUE for all but the most frequently captured species. Long-term (>20 years) trends in ALRRs at the nature reserve were positively correlated with UK national population trends recorded over the same period by an independent, labour-intensive monitoring scheme that counted birds at a large number of widely spread sites. Our results support previous claims that simple species lists could generate data useful for monitoring long-term population trends, particularly where such lists are collected systematically. However, further research on the efficiency of list reporting rates relative to more sophisticated methods is necessary, before list-based methods can be advocated for dedicated monitoring schemes in resource-poor regions.  相似文献
10.
For technical, environmental and economical reasons, industrial demands for process-fitted enzymes have evolved drastically in the last decade. Therefore, continuous efforts are made in order to get insights into enzyme structure/function relationships to create improved biocatalysts. Xylanases are hemicellulolytic enzymes, which are responsible for the degradation of the heteroxylans constituting the lignocellulosic plant cell wall. Due to their variety, xylanases have been classified in glycoside hydrolase families GH5, GH8, GH10, GH11, GH30 and GH43 in the CAZy database. In this review, we focus on GH11 family, which is one of the best characterized GH families with bacterial and fungal members considered as true xylanases compared to the other families because of their high substrate specificity. Based on an exhaustive analysis of the sequences and 3D structures available so far, in relation with biochemical properties, we assess biochemical aspects of GH11 xylanases: structure, catalytic machinery, focus on their "thumb" loop of major importance in catalytic efficiency and substrate selectivity, inhibition, stability to pH and temperature. GH11 xylanases have for a long time been used as biotechnological tools in various industrial applications and represent in addition promising candidates for future other uses.  相似文献
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