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911.
912.
Background and aims
The response of plants and soil to rain pulses determines seasonal variations in the exchange of materials and energy at the ecosystem scale in arid and semi-arid regions. We assessed how the ecosystem carbon exchange (NEE) of desert halophyte communities of different plant functional-types responds to summer precipitation pulses in Tamarix and Haloxylon communities.Methods
Plant water status, photosynthetic gas exchange, soil respiration and net ecosystem carbon exchange were measured to test the hypothesis that high physiological sensitivity may induce a greater changes in NEE resulting from the summer precipitation pulses in Haloxylon community.Results
Plant water status and photosynthetic assimilation did not differ before and after summer precipitation pulses in either community. In contrast, soil respiration and NEE responded strongly to summer precipitation events in both communities. At the ecosystem level, precipitation pulses induced a pulse of CO2 release, rather than absorption. The NEE response to summer precipitation was less in the deep-rooted Tamarix community, compared to the shallow-rooted Haloxylon community, which was even converted into a carbon source after summer precipitation inputs. As a result, the effect of summer precipitation inputs on soil respiration was more important than the plant (carbon assimilation) response in determining the ecosystem response to episodic precipitation pulses. 相似文献913.
A core functional region of the RFP1 promoter from Chinese wild grapevine is activated by powdery mildew pathogen and heat stress 总被引:1,自引:0,他引:1
Yihe Yu Weirong Xu Jie Wang Lei Wang Wenkong Yao Yan Xu Jiahua Ding Yuejin Wang 《Planta》2013,237(1):293-303
RING-finger proteins (RFP) function as ubiquitin ligases and play key roles in plant responses to biotic and abiotic stresses. However, little information is available on the regulation of RFP expression. Here, we isolate and characterize the RFP promoter sequence from the disease-resistant Chinese wild grape Vitis pseudoreticulata accession Baihe-35-1. Promoter-GUS fusion assays revealed that defense signaling molecules, powdery mildew infection, and heat stress induce VpRFP1 promoter activity. By contrast, the RFP1 promoter isolated from Vitis vinifera was only slightly induced by pathogen infection and heat treatment. By promoter deletion analysis, we found that the ?148 bp region of the VpRFP1 promoter was the core functional promoter region. We also found that, in Arabidopsis, VpRFP1 expressed under its own promoter activated defense-related gene expression and improved disease resistance, but the same construct using the VvRFP1 promoter slightly improve disease resistance. Our results demonstrated that the ?148 bp region of the VpRFP1 promoter plays a key role in response to pathogen and heat stress, and suggested that expression differences between VpRFP1 and VvRFP1 may be key for the differing disease resistance phenotypes of the two Vitis genotypes. 相似文献
914.
Guocai Zhong Huan Yan Haimin Wang Wenhui He Zhiyi Jing Yonghe Qi Liran Fu Zhenchao Gao Yi Huang Guangwei Xu Xiaofeng Feng Jianhua Sui Wenhui Li 《Journal of virology》2013,87(12):7176-7184
Primary Tupaia hepatocytes (PTHs) are susceptible to woolly monkey hepatitis B virus (WMHBV) infection, but the identity of the cellular receptor(s) mediating WMHBV infection of PTHs remains unclear. Recently, sodium taurocholate cotransporting polypeptide (NTCP) was identified as a functional receptor for human hepatitis B virus (HBV) infection of primary human and Tupaia hepatocytes. In this study, a synthetic pre-S1 peptide from WMHBV was found to bind specifically to cells expressing Tupaia NTCP (tsNTCP) and it efficiently blocked WMHBV entry into PTHs; silencing of tsNTCP in PTHs significantly inhibited WMHBV infection. Ectopic expression of tsNTCP rendered HepG2 cells susceptible to WMHBV infection. These data demonstrate that tsNTCP is a functional receptor for WMHBV infection of PTHs. The result also indicates that NTCP''s orthologs likely act as a common cellular receptor for all known primate hepadnaviruses. 相似文献
915.
Sung-Tae Hong Yan Jin Khikmat Anvarov Abdukhakim Khadjibaev Samin Hong Yusufjon Ahmedov Utkir Otaboev 《The Korean journal of parasitology》2013,51(3):383-385
Uzbekistan is endemic of cystic echinococcosis (CE). In order to estimate endemicity of CE, we collected data from emergency surgery due to CE in 2002-2010 and also investigated the prevalence of hydatid cysts in the liver and lungs of sheep at an abattoir in Uzbekistan from July 2009 to June 2010. In 14 emergency hospitals, 8,014 patients received surgical removal or drainage of CE during 2002-2010, and 2,966 patients were found in 2010. A total of 22,959 sheep were grossly examined of their liver and lungs, and 479 (2.1%) and 340 (1.5%) of them were positive for the cyst in the liver and lungs, respectively. Echinococcus granulosus is actively transmitted both to humans and sheep, and CE is a zoonotic disease of public health priority in Uzbekistan. 相似文献
916.
Bo Peng Yongxiang Li Yang Wang Cheng Liu Zhizhai Liu Yan Zhang Weiwei Tan Di Wang Yunsu Shi Baocheng Sun Yanchun Song Tianyu Wang Yu Li 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(3):773-789
Simultaneous improvement in grain yield and related traits in maize hybrids and their parents (inbred lines) requires a better knowledge of genotypic correlations between family per se performance (FP) and testcross performance (TP). Thus, to understand the genetic basis of yield-related traits in both inbred lines and their testcrosses, two F 2:3 populations (including 230 and 235 families, respectively) were evaluated for both FP and TP of eight yield-related traits in three diverse environments. Genotypic correlations between FP and TP, $ \hat{r}_{\text{g}} $ (FP, TP), were low (0–0.16) for grain yield per plant (GYPP) and kernel number per plant (KNPP) in the two populations, but relatively higher (0.32–0.69) for the other six traits with additive effects as the primary gene action. Similar results were demonstrated by the genotypic correlations between observed and predicted TP values based on quantitative trait loci positions and effects for FP, $ \hat{r}_{\text{g}} $ (M FP, Y TP). A total of 88 and 35 QTL were detected with FP and TP, respectively, across all eight traits in the two populations. However, the genotypic variances explained by the QTL detected in the cross-validation analysis were much lower than those in the whole data set for all traits. Several common QTL between FP and TP that accounted for large phenotypic variances were clustered in four genomic regions (bin 1.10, 4.05–4.06, 9.02, and 10.04), which are promising candidate loci for further map-based cloning and improvement in grain yield in maize. Compared with publicly available QTL data, these QTL were also detected in a wide range of genetic backgrounds and environments in maize. These results imply that effective selection based on FP to improve TP could be achieved for traits with prevailing additive effects. 相似文献
917.
Heterotrophic nitrification and aerobic denitrification by a novel Halomonas campisalis 总被引:1,自引:0,他引:1
Yan Guo Xuemei Zhou Yuguang Li Ke Li Caixia Wang Jianfei Liu Daojiang Yan Yilan Liu Dehui Yang Jianmin Xing 《Biotechnology letters》2013,35(12):2045-2049
A novel halophilic strain that could carry out heterotrophic nitrification and aerobic denitrification was isolated and named as Halomonas campisalis ha3. It removed inorganic nitrogen compounds (e.g. NO3 ?, NO2 ? and NH4 +) simultaneously, and grew well in the medium containing up to 20 % (w/v) NaCl. PCR revealed four genes in the genome of ha3 related to aerobic denitrification: napA, nirS, norB and nosZ. The optimal conditions for aerobic denitrification were pH 9.0, at 37 °C, with 4 % (w/v) NaCl and sodium succinate as carbon source. The nitrogen removal rate was 87.5 mg NO3 ?–N l?1 h?1. Therefore, this strain is a potential aerobic denitrifier for the treatment of saline wastewater. 相似文献
918.
Scott R. Higgins Ryan J. Lopez Eulyn Pagaling Tao Yan Michael J. Cooney 《Enzyme and microbial technology》2013,52(6-7):344-351
An electrogenic biofilm was developed on a macroporous chitosan-carbon nanotube (CHIT-CNT) electrode under constant poised potential (?0.25 V versus Ag/AgCl reference electrode) and flow through conditions utilizing the effluent of an anaerobic digester as both the inoculant and substrate for the electrogenic biofilm. After 125 days of inoculation the bioelectrode demonstrated an open circuit potential of ?0.62 V and a current density of 9.43 μA cm?3 (at ?0.25 V). Scanning electron microscopy images indicate thorough surface coverage of the biofilm with a high density of bacterial nanowires physically connecting bacteria to bacteria and bacteria to carbon nanotube (electrode surface) suggesting the nanowires are electrically conductive. DGGE was used to identify the major bacterial and archaeal populations. 相似文献
919.
Yu Tian Yan-feng Zhu Zhen Wu Jian-nan Feng Yan Li Bei-fen Shen Jian Sun 《Biotechnology letters》2013,35(4):523-528
B lymphocyte stimulator (BLyS) antagonists are new therapeutic reagents for treating the autoimmune diseases. Peptibodies can inhibit the bioactivity of BLyS, the same as other BLyS antagonists: decoyed BLyS receptors and anti-BLyS antibodies. In this study, a new optimized BLyS antagonist peptide was designed according to our previous work by the computer-aided homology modeling. Competitive ELISA showed that the peptide at 100 μg/ml could inhibit 54 % of the BCMA-Fc binding to BLyS. To maintain its stability and spatial conformation, the peptide was fused to human IgG1 Fc to form a peptide-Fc fusion protein—a novel peptibody by gene engineering. ELISA indicated that the peptibody could bind with BLyS in dosage-dependent manner as BCMA-Fc did. This study highlights the possibility of designing and optimizing BLyS antagonist peptides with high biopotency by the computer-aided design. Thus, these peptides could neutralize BLyS activity and be potential antagonists to treat autoimmune diseases related with BLyS overexpression. 相似文献
920.
Teng-Fei Xu Jiang Xiang Feng-Ju Li Tie-Mei Li Yi-He Yu Yue-Jin Wang Yan Xu 《Acta Physiologiae Plantarum》2013,35(8):2355-2364
Among the 17 plant pathogenesis-related (PR) protein families, only PR10 family is intracellular and cytosolic. PR proteins are expressed in response to pathogen challenge and abiotic stresses in higher plants. However, the molecular mechanisms of their actions remain poorly understood. In a previous work, we isolated a PR10 gene from Erysiphe necator-resistant Chinese wild Vitis sp. (Baihe-35-1) and it was designated as VpPR10.1. In this study, yeast two-hybrid method was used to screen proteins interacting with VpPR10.1 proteins. Twenty-one ESTs were isolated and sequenced. All sequences were compared using BLASTx to identify presumptive orthologs. Several proteins associated with VpPR10.1 protein were screened, including CNR8, UFGT6, HSP, DEAD-box, Trx h2, Grx C9 and GLOX. These proteins are closely related to defensive action of plants against pathogens and abiotic stresses. Our results reveal that VpPR10.1 gene may be involved in hormone signaling, programmed cell death and defense responses of grapevine. 相似文献