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141.
142.
SPINDLY(SPY)作为一负调节子参与GA的信号转导,34肽重复结构(TPR)与C-端区域对其正常功能都十分重要。SPY基因在植物中呈组成型表达,其蛋白主要出现在细胞核部位。SPY蛋白与动物中的氧连N-乙酰葡萄糖胺转移酶(OGT)具有广泛的同源性,两者可能有着类似的作用机制。本文主要介绍GA突变体、SPY基因、SPY蛋白及其在大麦中的同源物HvSPY的结构与功能相关方面的一些研究进展。 相似文献
143.
Li S Tao L Jiao X Liu H Cao Y Lopez B Luan RH Christopher T Ma XL 《Apoptosis : an international journal on programmed cell death》2007,12(10):1795-1802
Whole body non-penetrating trauma causes myocardial infarction in humans and mechanical trauma (MT) results in cardiac dysfunction
in animals. Our recent study demonstrated that incubation of cardiomyocytes with plasma isolated from MT animals causes significant
cardiomyocyte apoptosis that can be blocked by neutralization of TNFα. The present study attempted to obtain direct in vivo
evidence to support that overproduction of TNFα plays a causative role in trauma-induced cardiomyocyte apoptosis. Non-lethal
MT caused significant TNFα overproduction (2.4-fold at 1.5 h after MT) and increased cardiomyocyte apoptosis (starting 3 h
and peaking 12 h after MT). Pharmacological inhibition of TNFα with etanercept or TNFα gene deletion reduced post-trauma myocyte
apoptosis (P < 0.01). Expression of iNOS and NADPH oxidase, overproduction of NO and
, and excessive protein nitration in the MT heart were all significantly reduced in etanercept-treated or TNFα−/− mice, suggesting that oxidative/nitrative stress may contribute to TNFα-initiated myocyte apoptosis in MT hearts. Additional
experiments demonstrated that inhibiting iNOS (1400W) or NADPH oxidase (apocynin), or scavenging peroxynitrite (FP15) significantly
reduced myocyte apoptosis in MT animals (P < 0.01). Collectively, these data demonstrated that non-lethal mechanical trauma caused significant TNFα production that
in turn stimulated myocardial apoptosis via oxidative/nitrative stress. 相似文献
144.
145.
基于西北地区143个气象站点的气象数据,采用FAO-56 Penman-Monteith公式计算潜在蒸发量,并结合降水量计算西北地区1989—2019年干燥度指数(AI),采用Mann-Kendall趋势分析、小波分析、偏微分方程等方法来揭示其变化趋势、变化周期和气候因子对AI的贡献率。结果表明: 1989—2019年,西北地区AI整体呈不显著的减小趋势,其中,青海呈显著减小趋势,新疆呈不显著的上升趋势;研究区AI在2010年发生了突变,AI变化存在1个17年的主周期。西北地区AI呈现出由东南部向中部、西北部向中部增加的空间格局。西北地区AI变化的倾向率为-1.267·(10 a)-1,其中,甘肃、宁夏、陕西、青海和新疆AI变化的倾向率分别为-1.17、-0.41、-0.49、-1.77和-2.73·(10 a)-1。青海小灶火、新疆库尔勒、阿克苏和吐鲁番地区干旱风险发生的可能性较高。降水量和实际水汽压是影响甘肃、宁夏、青海、陕西AI变化的主要气侯因子,影响新疆AI变化的主要气侯因子为潜在蒸散、太阳辐射和平均气温。 相似文献
146.
Identification of the novel recessive gene pi55(t) conferring resistance to Magnaporthe oryzae 总被引:2,自引:0,他引:2
XiuYing He XinQiong Liu Li Wang Ling Wang Fei Lin YongSheng Cheng ZhaoMing Chen YaoPing Liao QingHua Pan 《中国科学:生命科学英文版》2012,55(2):141-149
The elite rice cultivar Yuejingsimiao 2 (YJ2) is characterized by a high level of grain quality and yield, and resistance
against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces,
which is a higher frequency than that shown by the well-known resistance (R) gene donor cultivars such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F2 and F4 populations indicated the resistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative
R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a bulked-segregant analysis using
genome-wide selected SSR markers with F4 lines that segregated into 3 resistant (R):1 susceptible (S) or 1R:3S. The recessive R gene on chromosome 8 was further mapped to an interval ≈1.9 cM/152 kb in length by linkage analysis with genomic position-ready
markers in the mapping population derived from an F4 line that segregated into 1R:3S. Given that no major R gene was mapped to this interval, the novel R gene was designated as pi55(t). Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare,
two genes that encode a leucine-rich repeat-containing protein and heavy-metal-associated domain-containing protein, respectively,
were suggested as the most likely candidates for pi55(t). 相似文献
147.
Chen ZY Zeng DY Hu YT He YW Pan N Ding JP Cao ZJ Liu ML Li WX Yi H Jiang L Wu YL 《PloS one》2012,7(4):e35154
Background
Although the basic scorpion K+ channel toxins (KTxs) are well-known pharmacological tools and potential drug candidates, characterization the acidic KTxs still has the great significance for their potential selectivity towards different K+ channel subtypes. Unfortunately, research on the acidic KTxs has been ignored for several years and progressed slowly.Principal Findings
Here, we describe the identification of nine new acidic KTxs by cDNA cloning and bioinformatic analyses. Seven of these toxins belong to three new α-KTx subfamilies (α-KTx28, α-KTx29, and α-KTx30), and two are new members of the known κ-KTx2 subfamily. ImKTx104 containing three disulfide bridges, the first member of the α-KTx28 subfamily, has a low sequence homology with other known KTxs, and its NMR structure suggests ImKTx104 adopts a modified cystine-stabilized α-helix-loop-β-sheet (CS-α/β) fold motif that has no apparent α-helixs and β-sheets, but still stabilized by three disulfide bridges. These newly described acidic KTxs exhibit differential pharmacological effects on potassium channels. Acidic scorpion toxin ImKTx104 was the first peptide inhibitor found to affect KCNQ1 channel, which is insensitive to the basic KTxs and is strongly associated with human cardiac abnormalities. ImKTx104 selectively inhibited KCNQ1 channel with a Kd of 11.69 µM, but was less effective against the basic KTxs-sensitive potassium channels. In addition to the ImKTx104 toxin, HeTx204 peptide, containing a cystine-stabilized α-helix-loop-helix (CS-α/α) fold scaffold motif, blocked both Kv1.3 and KCNQ1 channels. StKTx23 toxin, with a cystine-stabilized α-helix-loop-β-sheet (CS-α/β) fold motif, could inhibit Kv1.3 channel, but not the KCNQ1 channel.Conclusions/Significance
These findings characterize the structural and functional diversity of acidic KTxs, and could accelerate the development and clinical use of acidic KTxs as pharmacological tools and potential drugs. 相似文献148.
149.
150.
Zi Feng Yang Chris Ka Pun Mok Xiao Qing Liu Xiao Bo Li Jian Feng He Wen Da Guan Yong Hao Xu Wei Qi Pan Li Yan Chen Yong Ping Lin Shi Guan Wu Si Hua Pan Ji Cheng Huang Guo Yun Ding Kui Zheng Chang Wen Ke Jin Yan Lin Yong Hui Zhang Horace Hok Yeung Lee Wen Kuan Liu Chun Guang Yang Rong Zhou Joseph Sriyal Malik Peiris Yi Min Li Rong Chang Chen Ling Chen Nan Shan Zhong 《PloS one》2015,10(2)
BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome. 相似文献