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81.

Background

Although a number of proteins and genes relevant to schizophrenia have been identified in recent years, few are known about the exact metabolic pathway involved in this disease. Our previous proteomic study has revealed the energy metabolism abnormality in subchronic MK-801 treated rat, a well-established animal model for schizophrenia. This prompted us to further investigate metabolite levels in the same rat model to better delineate the metabolism dysfunctions and provide insights into the pathology of schizophrenia.

Methods

Metabolomics, a high-throughput investigatory strategy developed in recent years, can offer comprehensive metabolite-level insights that complement protein and genetic findings. In this study, we employed a nondestructive metabolomic approach (1H-MAS-NMR) to investigate the metabolic traits in cortex and hippocampus of MK-801 treated rats. Multivariate statistics and ingenuity pathways analyses (IPA) were applied in data processing. The result was further integrated with our previous proteomic findings by IPA analysis to obtain a systematic view on our observations.

Results

Clear distinctions between the MK-801 treated group and the control group in both cortex and hippocampus were found by OPLS-DA models (with R2X = 0.441, Q2Y = 0.413 and R2X = 0.698, Q2Y = 0.677, respectively). The change of a series of metabolites accounted for the separation, such as glutamate, glutamine, citrate and succinate. Most of these metabolites fell in a pathway characterized by down-regulated glutamate synthesis and disturbed Krebs cycle. IPA analysis further confirmed the involvement of energy metabolism abnormality induced by MK-801 treatment.

Conclusions

Our metabolomics findings reveal systematic changes in pathways of glutamate metabolism and Krebs cycle in the MK-801 treated rats’ cortex and hippocampus, which confirmed and improved our previous proteomic observation and served as a valuable reference to the etiology research of schizophrenia.  相似文献   
82.
一种长效胰岛素的分子设计和目标产品制备   总被引:1,自引:0,他引:1  
按照“增加次级键,稳化寡聚体”以产生长效性的分子设计原理,以精确的胰岛素三维结构为基础,通过计算机模拟提出对残基B2-Val-Lys/Arg的分子改造方案,并预测它能在不影响生物活力的条件下产生长效效应。在此基础上,用化学半合成的方法制备了目标产品desBl-LysB2胰岛索,并进行了产物活力和基本性质测定。结果表明,与天然胰岛素相比较,该目标产品保有基本的降血糖生物活力(82%),表现出显著的长效效应。  相似文献   
83.
环境雌激素的微生物降解   总被引:4,自引:0,他引:4  
雌激素作为环境内分泌干扰物的一类重要物质,生物降解法是最为经济、最为绿色和最为适用的去除方法。通过分析雌激素的主要来源和危害、国内外雌激素降解菌的筛选与鉴定、类固醇雌激素降解酶的表达与检测、雌激素降解菌的基因组学特征以及雌激素的降解途径和机制,进一步阐述了雌激素生物降解的研究现状与进展,对未来的研究工作作出了展望。  相似文献   
84.
Liu  Qing  Wang  Chun  Jiao  Xiaozhen  Zhang  Huawei  Song  Lili  Li  Yanxin  Gao  Caixia  Wang  Kejian 《中国科学:生命科学英文版》2019,62(1):1-7
The CRISPR/Cas system has been extensively applied to make precise genetic modifications in various organisms. Despite its importance and widespread use, large-scale mutation screening remains time-consuming, labour-intensive and costly. Here, we developed Hi-TOM(available at http://www.hi-tom.net/hi-tom/), an online tool to track the mutations with precise percentage for multiple samples and multiple target sites. We also described a corresponding next-generation sequencing(NGS) library construction strategy by fixing the bridge sequences and barcoding primers. Analysis of the samples from rice, hexaploid wheat and human cells reveals that the Hi-TOM tool has high reliability and sensitivity in tracking various mutations, especially complex chimeric mutations frequently induced by genome editing. Hi-TOM does not require special design of barcode primers,cumbersome parameter configuration or additional data analysis. Thus, the streamlined NGS library construction and comprehensive result output make Hi-TOM particularly suitable for high-throughput identification of all types of mutations induced by CRISPR/Cas systems.  相似文献   
85.
胡纫秋  王森 《动物学研究》1989,10(3):185-193
经Sephadex G-50和Sp-Sephadex C-25两次柱层析,从山东马氏钳蝎(Buthus martensi Karsch)粗毒中分离纯化得到8种哺乳动物神经毒(BmK Ⅰ-Ⅷ)和一种甲壳动物神经毒(CT)。纯度鉴定表明它们在聚丙烯酰胺凝胶电泳和等电聚焦电泳时均呈现一条主带。除BmK Ⅳ外,其等电点在7.9—9.1之间,但BmK Ⅳ呈酸性,其等电点为5.3。SDS-PAGE测得它们的分子量为6000—8000。哺乳动物神经毒的氨基酸组成中Asp的含量较多,而不含Met,CT的氨基酸组成中Gly的含量高于Asp,且含Met,但缺乏Ile和Val。 Bmk Ⅲ和Bmk Ⅳ的N端部分序列比较,发现N端序列具有较强的保守性,15个残基中相同的残基占60%,各组份的CD谱显示它们的主链构象很相似,主要二级结构是β折迭,不含或含较少α-螺旋。  相似文献   
86.
以长白落叶松(Larix olgensis)未成熟合子胚为外植体诱导胚性愈伤组织, 通过调节影响体胚发生的营养物质和植物生长调节剂配比, 进行愈伤组织的胚性恢复与保持以及体胚发生再生体系的优化。结果表明: 不同无性系之间胚性愈伤组织诱导率差异显著, 胚性愈伤组织在S+0.2 mg·L -1NAA+0.5 mg·L -1BA+0.5 mg·L -1KT+0.5 g·L -1谷氨酰胺+0.5 g·L -1水解酪蛋白+30 g·L -1蔗糖及3.0 g·L -1植物凝胶培养条件下, 可以恢复胚性并长久保持。在S+20 mg·L -1ABA+60 g·L -1PEG4000+60 g·L -1蔗糖及3.0 g·L -1植物凝胶条件下分化培养6周, 体胚发生率可达100%。将正常发育的体胚先在WPM+ 6 mg·L -1间苯三酚+1.0 g·L -1活性炭+3.0 mg·L -1VB1+20 g·L -1蔗糖及3.0 g·L -1植物凝胶条件下培养2周, 再转接至B5+ 0.4 mg·L -1NAA+1.0 mg·L -1IBA+0.5 mg·L -1GA3+2.0 mg·L -1VB1+1.0 g·L -1活性炭+20 g·L -1蔗糖及3.0 g·L -1植物凝胶条件下培养2周, 可见子叶舒展、下胚轴伸长且根系正常的体胚苗。该研究建立了长白落叶松胚性愈伤组织胚性恢复与保持方法, 并进一步优化了体胚发生的植株再生体系, 为林木资源快速繁育和遗传改良奠定了基础。  相似文献   
87.
Drug medications inevitably affect not only their intended protein targets but also other proteins as well. In this study we examined the hypothesis that drugs that share the same therapeutic effect also share a common therapeutic mechanism by targeting not only known drug targets, but also by interacting unexpectedly on the same cryptic targets. By constructing and mining an Alzheimer''s disease (AD) drug-oriented chemical-protein interactome (CPI) using a matrix of 10 drug molecules known to treat AD towards 401 human protein pockets, we found that such cryptic targets exist. We recovered from CPI the only validated therapeutic target of AD, acetylcholinesterase (ACHE), and highlighted several other putative targets. For example, we discovered that estrogen receptor (ER) and histone deacetylase (HDAC), which have recently been identified as two new therapeutic targets of AD, might already have been targeted by the marketed AD drugs. We further established that the CPI profile of a drug can reflect its interacting character towards multi-protein sets, and that drugs with the same therapeutic attribute will share a similar interacting profile. These findings indicate that the CPI could represent the landscape of chemical-protein interactions and uncover “behind-the-scenes” aspects of the therapeutic mechanisms of existing drugs, providing testable hypotheses of the key nodes for network pharmacology or brand new drug targets for one-target pharmacology paradigm.  相似文献   
88.
遮荫对新疆紫草育苗的影响   总被引:1,自引:0,他引:1  
目的 探讨新疆紫草育苗的最佳遮荫条件.方法 采用不同的遮荫条件,研究了遮荫处理对新疆紫草原生苗生长量和成活率的影响.结果 结果表明,不同强度的遮荫处理对原生苗的叶面积、成活率、地下生长量影响显著.适度遮荫可以增加叶面积和地下生长量,提高幼苗成活率,结论 采用30%遮荫率的遮荫处理能够同时满足增加生长量和提高成活率的要求,同时避免了叶片先端的日灼伤害.  相似文献   
89.
众所周知,繁殖鸟能否成功繁殖,并使后代存活取决于许多因素.繁殖鸟往往需要消耗很多的精力来进行繁殖,这对它们来说十分不利.但在部分鸟类中,存在一种常见的生殖合作形式,就是非双亲个体帮助繁殖鸟来喂养它们的后代.帮手鸟帮助它们筑巢,孵卵,觅食,喂食和保护领域等,极大提高了繁殖鸟的适合度,即所谓的"帮手效应".同时帮手鸟也获得了未来的适合度.  相似文献   
90.
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