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81.
马铃薯致病疫霉研究进展   总被引:3,自引:0,他引:3  
马铃薯致病疫霉(Phytophthora infestans)属卵菌纲(Oomycetes)霜霉目(Peronosporales)腐霉科(Pythiaceae)疫霉属(Phytophthora),是马铃薯和番茄晚疫病病原菌。由于晚疫病对马铃薯生产的毁灭性和严重性,对致病疫霉的研究一直是关注的重点。本文首先对病害引起的症状、发生特点及流行规律进行阐述,对有性生殖发生的遗传规律和多种交配型共存的大环境下病原菌群体结构变异特点进行归纳总结。随着2009年致病疫霉基因组测序的完成,本文比对了疫霉属目前已完成测序各个种的基因组学特点,介绍了致病疫霉在效应子克隆方面的研究进展及线粒体基因组研究现状,阐述了功能基因组学的两个重要技术:高密度遗传连锁图谱(high density linkage mapping)和全基因组关联分析(genome-wide association study,GWAS),及其在挖掘致病疫霉重要功能基因上的应用。本文有助于了解致病疫霉研究热点及后续突破方向,可为深入解析致病疫霉的功能基因及致病机制提供参考,对开发马铃薯晚疫病菌药物靶标及预测病害的大规模流行趋势也具有重要意...  相似文献   
82.
It is a renewed pleasure to wish our authors, editorial board members, and readership an excellent new year, full of professional and personal satisfactions. According to the Chinese Horoscope, 2023, the Year of Water Rabbit, is predicted to be quiet; a year to step back, assess the situation and make plans. It will be the time to carefully appraise, with the patience of the Water Rabbit, the future and scientific wealth of our Journal. Based on a few aspects of the CCN3 biology status that remain open questions, I am presenting below a short summary of a few CCN research directions that in my eyes, become necessary to undertake through wide-angle collaborative approaches.  相似文献   
83.
In celebration of the twentieth anniversary of the inception of the CCN society, and of the first post-Covid-19 live meeting, the executive board of the ICCNS had chosen Nice as the venue for the 11th International workshop on the CCN family of genes. On this occasion participation in the meeting was extended to colleagues from other cell signaling fields who were invited to present both an overview of their work and the future directions of their laboratory. Also, for the first time, the members of the JCCS Editorial Board were invited to participate in a JCCS special session during which all aspects of the journal « life » were addressed and opened to free critical discussion. The scientific presentations and the discussions that followed showed once more that an expansion of the session topics was beneficial to the quality of the meeting and confirmed that the ARBIOCOM project discussed last April in Nice was now on track to be launched in 2023. The participants unanimously welcomed Professor Attramadal’s proposition to organize the 2024, 12th International CCN workshop in Oslo, Norway.  相似文献   
84.
With accumulating dysregulated circular RNAs(circRNAs) in pathological processes,the regulatory functions of circRNAs, especially circRNAs as microRNA(miRNA) sponges and their interactions with RNA-binding proteins(RBPs), have been widely validated. However, the collected information on experimentally validated circRNA–disease associations is only preliminary.Therefore, an updated CircR2Disease database providing a comprehensive resource and web tool to clarify the relationships between circRNAs...  相似文献   
85.
鼎湖山气候顶极群落种间联结变化   总被引:9,自引:0,他引:9  
彭李菁 《生态学报》2006,26(11):3732-3739
通过与前人工作的比较,研究鼎湖山地带性植被气候顶极群落种间联结22a来的变化。研究结果表明,经过了22a,其种类结构尤其优势种类组成没有明显变化,这反映了厚壳桂群落处于演替的顶极阶段,其物种组成上具有相对的稳定性。现群落中的种间联结强度比1984年趋于缓和,高联结值的种对减少,完全正或负联结的种对,1984年为15,而2006年为5;一般联结的种对大为增加,联结值40以下的1984年为约1,2,而2006年为约3/5弱,表明群落的种群更趋向于独立分布而不是联结分布。生物竞争特性对种间关系有一定1的影响。主要原因是与物种对群落的选择和群落对生存物种的选择和淘汰有密切的关系。特别虫灾事件使该群落的群落结构有了较大的波动,但是群落的性质没有改变。反映了厚壳桂群落作为地带性气候顶级群落具有稳定性与较强的自我调节、自我恢复能力。整个群落的种群随时间进程趋向于独立分布,但这种分布趋势有其相对性,其中强独立分布(完全没有种间联结)的种群分布格局变弱,弱独立分布(只有微弱种间联结)的种群格局变强。  相似文献   
86.
硝基苯污染物的生物降解途径   总被引:5,自引:0,他引:5  
硝基苯是一种有毒化合物,目前,关于硝基苯污染物的生物降解已进行了大量的研究。综述了生物降解硝基苯的两种主要途径氧化途径和部分还原途径,介绍了两种途径降解硝基苯的具体机制及相关酶和编码基因的特点,并对两种降解途径进行了简要的对比分析,为硝基苯及其它有机污染物生物降解技术的开发应用提供依据。  相似文献   
87.
茄子是重要的园艺作物,也是茄科植物中种植最广泛的蔬菜之一。茄子果实相关农艺性状是一种复杂的数量性状,传统育种选育效率低、周期长。高通量测序技术与生物信息学技术的快速发展,使得全基因组关联分析(genome-wide association study, GWAS)在解析茄子果实相关复杂农艺性状的遗传规律方面展现出巨大的应用前景。本文对全基因组关联分析在茄子的果形、果色等果实相关农艺性状中的研究进展进行了综述;针对茄子数量性状遗传研究中普遍存在的“丢失遗传力”(missing heritability)问题,从4个GWAS策略在茄子果实相关农艺性状研究中的应用热点出发,提出了未来茄子GWAS的发展对策;并结合当前茄子遗传改良的实践需求,展望了GWAS策略在茄子分子育种领域的广阔应用前景。本文为今后利用GWAS解析各种茄子果实相关性状的遗传基础以及选育符合消费者需求的果实材料提供了理论依据和参考。  相似文献   
88.
89.
Microbes play important roles in human health and disease. The interaction between microbes and hosts is a reciprocal relationship, which remains largely under-explored. Current computational resources lack manually and consistently curated data to connect metagenomic data to pathogenic microbes, microbial core genes, and disease phenotypes. We developed the MicroPhenoDB database by manually curating and consistently integrating microbe-disease association data. MicroPhenoDB provides 5677 non-redundant associations between 1781 microbes and 542 human disease phenotypes across more than 22 human body sites. MicroPhenoDB also provides 696,934 relationships between 27,277 unique clade-specific core genes and 685 microbes. Disease phenotypes are classified and described using the Experimental Factor Ontology (EFO). A refined score model was developed to prioritize the associations based on evidential metrics. The sequence search option in MicroPhenoDB enables rapid identification of existing pathogenic microbes in samples without running the usual metagenomic data processing and assembly. MicroPhenoDB offers data browsing, searching, and visualization through user-friendly web interfaces and web service application programming interfaces. MicroPhenoDB is the first database platform to detail the relationships between pathogenic microbes, core genes, and disease phenotypes. It will accelerate metagenomic data analysis and assist studies in decoding microbes related to human diseases. MicroPhenoDB is available through http://www.liwzlab.cn/microphenodb and http://lilab2.sysu.edu.cn/microphenodb.  相似文献   
90.
Although several genome‐wide association studies (GWAS) of non‐syndromic cleft lip with or without cleft palate (NSCL/P) have been reported, more novel association signals are remained to be exploited. Here, we performed an in‐depth analysis of our previously published Chinese GWAS cohort study with replication in an extra dbGaP case‐parent trios and another in‐house Nanjing cohort, and finally identified five novel significant association signals (rs11119445: 3’ of SERTAD4, P = 6.44 × 10−14; rs227227 and rs12561877: intron of SYT14, P = 5.02 × 10−13 and 2.80 × 10−11, respectively; rs643118: intron of TRAF3IP3, P = 4.45 × 10−6; rs2095293: intron of NR6A1, P = 2.98 × 10−5). The mean (standard deviation) of the weighted genetic risk score (wGRS) from these SNPs was 1.83 (0.65) for NSCL/P cases and 1.58 (0.68) for controls, respectively (P = 2.67 × 10−16). Rs643118 was identified as a shared susceptible factor of NSCL/P among Asians and Europeans, while rs227227 may contribute to the risk of NSCL/P as well as NSCPO. In addition, sertad4 knockdown zebrafish models resulted in down‐regulation of sox2 and caused oedema around the heart and mandibular deficiency, compared with control embryos. Taken together, this study has improved our understanding of the genetic susceptibility to NSCL/P and provided further clues to its aetiology in the Chinese population.  相似文献   
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