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91.
A field experiment was conducted to determine the seasonal patterns of arbuscular mycorrhiza (AM) in a dryland winter wheat
(Triticum aestivum L.) system and to determine wheat growth and P uptake responses to inoculation with mycorrhizal fungus. Broadcast-incorporated
treatments included (1) no inoculation with mycorrhizal fungus, with and without P fertilizer, and (2) mycorrhizal fungal
inoculation at a rate of 5000 spores of Glomus intraradices (Schenck and Smith), per 30 cm in each row, with and without fertilizer P. Winter wheat was seeded within a day after treatments
were imposed, and roots were sampled at five growth stages to quantify AM. Shoot samples were also taken for determination
of dry matter, grain yield and yield components, and N and P uptake. No AM infection was evident during the fall months following
seeding, which was characterized by low soil temperature, while during the spring, the AM increased gradually. Increases in
wheat grain yields by enhanced AM were of similar magnitude to the response obtained from P fertilization. However, responses
differed at intermediate growth stages. At the tillering stage, P uptake was mainly increased by P fertilization but not by
fungal inoculation. At harvest, enhanced AM increased P uptake regardless of whether or not fertilizer P was added. The AM
symbiosis increased with rising soil temperatures in the spring, in time to enhance late-season P accumulation and grain production.
Accepted: 15 July 1998 相似文献
92.
93.
94.
Changtian Pan Dandan Yang Xiaolin Zhao Chen Jiao Yanqiu Yan Anthony Tumbeh Lamin‐Samu Qiaomei Wang Xiangyang Xu Zhangjun Fei Gang Lu 《Plant, cell & environment》2019,42(4):1205-1221
High temperature (HT) is becoming an increasingly serious factor in limiting crop production with global climate change. During hot seasons, owing to prevailing HT, cultivated tomatoes are prone to exhibiting stigma exsertion, which hampers pollination and causes fruit set failure. However, the underlying regulatory mechanisms of the HT‐induced stigma exsertion remain largely unknown. Here, we demonstrate that stigma exsertion induced by HT in cultivated tomato is caused by more seriously shortened stamens than pistils, which is different from the stigma exsertion observed in wild tomato species. Under the HT condition, the different responses of pectin, sugar, expansin, and cyclin cause cell wall remodelling and differentially localized cell division and selective cell enlargement, which further determine the lengths of stamens and pistils. In addition, auxin and jasmonate (JA) are implicated in regulating cell division and cell expansion in stamens and pistils, and exogenous JA instead of auxin treatment can effectively rescue tomato stigma exsertion through regulating the JA/COI1 signalling pathway. Our findings provide a better understanding of stigma exsertions under the HT condition in tomato and uncover a new function of JA in improving plant abiotic stress tolerance. 相似文献
95.
文章运用Agilent 双标记表达谱芯片, 基于已建立的苏太猪大肠杆菌F18菌株敏感性和抗性型全同胞配对个体, 分析十二指肠组织基因表达谱差异, 旨在筛选导致仔猪断奶后腹泻和水肿病发生的大肠杆菌F18菌株受体相关基因, 探讨造成大肠杆菌病抗性和敏感性资源家系抗性差异的分子生物学机理。研究结果显示, 以Fold change绝对值大于2倍进行筛选, 在敏感型(GG基因型)对抗性型(AA基因型)配对组中, 差异基因共13个, 其中上调6个, 下调7个, 在以敏感型(AG基因型)对抗性型(AA基因型)配对组中, 共筛选出差异基因6个, 其中上调4个, 下调2个。经GO分析发现差异基因的生物学过程主要涉及免疫应答、胞外区修饰(如糖基化)、细胞黏附、信号转导等。通路发现大肠杆菌F18菌株抵抗性和敏感性差异基因主要涉及糖脂合成代谢以及炎症免疫相关通路, 经芯片筛选出的相关基因的功能还需进一步的研究验证。 相似文献
96.
Pan Kai-Yu 《植物分类学报:英文版》1988,26(6):429-442
Ten new species, three new varieties and a new section of the family Gesneriaceae are described from China in the present paper. They are Tremacron urceolatum
K. Y. Pan from Muli of SW Sichuan, T. obliquifolium K. Y. Pan from Miyi and Yanyuan
of SW Sichuan, T. aurantiacum K. Y. Pan from Mabian and Pinshan of S Sichuan, lsometrum
Sect. Chorianthera W. T. Wang et K. Y. Pan (with I. eximium Chun as the section type),
Isometrum eximium Chun ex K. Y. Pan from Jiulong, Muli and Jinyang of SW Sichuan;
Ancylostemon mairei (Levl.) Craib var. emeiensis K. Y. Pan from Mt. Emei of Sichuan, A.
aureus (Franch.) Burtt var. angustifolius K. Y. Pan from Zhenkang of SW Yunnan, A. gamosepalus K. Y. Pan from Hanyuan, Yanyuan and Yuexi of SW Sichuan, A. rhombifolius K.
Y. Pan from Meigu of SW Sichuan, A. ronganensis K. Y. Pan from Rong an of Guangxi;
Corallodiscus flabellatus) (Craib) Burtt var. puberulus K.Y. Pan from Zhongdian and Deqin
of NW Yunnan, Nanchuan of S Sichuan and Zayü of Xizang (Tibet), Beccarinda minima
K. Y. Pan from Jinxiu and Xiangzhou of Guangxi, Boeica stolonifera K. Y. Pan from Fangcheng, Shiwandashan, Pingnan and Dongxing of S Guangxi, B. multinervia K. Y. Pan from
Yingjiang of W Yunnan, and Paraboea barbatipes K. Y. Pan from Napo of W Guangxi and
Xichou of SE Yunnan. 相似文献
97.
98.
Guo Zhao Xiaobing Gu Xinlun Lu Jinjin Pan Zhiqiang Duan Kunkun Zhao Min Gu Qingtao Liu Liang He Jian Chen Shengqiang Ge Yanhong Wang Sujuan Chen Xiaoquan Wang Daxin Peng Hongquan Wan Xiufan Liu 《PloS one》2012,7(9)
There has been multiple evidence that domestic poultry may act as a vessel for the generation of novel influenza A viruses. In this study, we have analyzed the evolution and pathogenicity of 4 H5N2 avian influenza viruses isolated from apparently healthy poultry from H5N1 virus endemic areas in China. Phylogenetic analysis revealed that two of these viruses, A/duck/Eastern China/1111/2011 (DK/EC/1111/11) and A/goose/Eastern China/1112/2011 (GS/EC/1112/11) were derived from reassortment events in which clade 2.3.4 highly pathogenic avian influenza (HPAI) H5N1 viruses acquired novel neuraminidase and nonstructural protein genes. Another two isolates, A/chicken/Hebei/1102/2010 (CK/HB/1102/10) and A/duck/Hebei/0908/2009 (DK/HB/0908/09), possess hemagglutinin (HA) gene belong to clade 7 H5 viruses and other genes from endemic H9N2 viruses, or from viruses of various subtypes of the natural gene pool. All of these H5N2 isolates bear characteristic sequences of HPAI virus at the cleavage site of HA, and animal experiments indicated that all of these viruses but DK/HB/0908/09 is highly pathogenic to chickens. In particular, DK/EC/1111/11 and GS/EC/1112/11 are also highly pathogenic to ducks and moderately pathogenic to mice. All of these 4 viruses were able to replicate in domestic ducks and mice without prior adaptation. The emergence of these novel H5N2 viruses adds more evidence for the active evolution of H5 viruses in Asia. The maintenance of the highly pathogenic phenotype of some of these viruses even after reassortment with a new NA subtypes, their ability to replicate and transmit in domestic poultry, and the pathogenicity in the mammalian mouse model, highlight the potential threat posed by these viruses to both veterinary and public health. 相似文献
99.
蝙蝠是很多病原微生物的自然宿主, 全球多项研究表明蝙蝠是巴尔通体(Bartonella species)的主要宿主。为了解滇西南地区蝙蝠中巴尔通体的流行特征, 我们于2015-2017年间在云南省4个地区应用网捕法捕获蝙蝠3种305只。经种类鉴定后采集肝脾组织, 提取核酸, 通过TaqMan实时荧光定量PCR方法检测巴尔通体的tmRNA基因ssrA, 并进行测序鉴定和系统发育分析。结果发现172只蝙蝠检出该基因, 总感染率为56.4%; 其中临沧、西双版纳、保山和瑞丽4个采样点的蝙蝠感染率分别为50.0% (22/44)、61.7% (29/47)、62.1% (18/29)和55.7% (103/185)。中菊头蝠(Rhinolophus affinis)、小菊头蝠(R. blythi)和棕果蝠(Rousettus leschenaultii)的感染率分别为50.0% (22/44)、62.1% (18/29)和56.9% (132/232), 差异没有统计学意义(χ2 = 1.135, P = 0.567), 表明巴尔通体在云南当地的蝙蝠种群中高度流行。定量PCR扩增产物2次扩增后测序获得37个巴尔通体ssrA序列, 属于10个系统发育分支, 其中1个为伊丽莎白巴尔通体(B. elizabethae)、特利波契巴尔通体(B. tribocorum)和克拉斯诺夫巴尔通体(B. krasnovii)的近缘种。其余序列与已知巴尔通体距离较远, 与亚洲、欧洲和美洲等其他地域来源于蝙蝠的巴尔通体近缘。遗传多样性分析显示, ssrA基因的核苷酸多样性指数(π)为0.11381 ± 0.00928, 基因型多样性指数(Hd)为0.985 ± 0.010, 形成29个基因型(单倍型), 说明云南蝙蝠巴尔通体具有丰富的遗传多样性。通过对本研究标本与全球相关序列的系统发育网络重建, 分析全球蝙蝠巴尔通体的地理和宿主分布特征, 可以看出巴尔通体与蝙蝠之间存在显著的宿主特异性关联。因此可初步确定蝙蝠-巴尔通体具有协同进化特征, 同时受到地理隔离的影响。 相似文献
100.
Hui Liu Guangdi Chen Yifeng Pan Zexin Chen Wen Jin Chuan Sun Chunjing Chen Xuanjun Dong Kun Chen Zhengping Xu Shanchun Zhang Yunxian Yu 《PloS one》2014,9(10)