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991.
992.
Z. J. Chen H. Yang C. C. Liu A. Mittelman S. Ferrone 《Pigment cell & melanoma research》1990,3(Z2):113-122
993.
本文主要就激光在国外兽医领域的激光内窥镜外科、肿瘤外科、眼外科、小动物外科以及激光动力学治疗等方面的应用及基础理论方面的研究进展进行综述。 相似文献
994.
Chi Zhang Hanqin Tian Shufen Pan Mingliang Liu Graeme Lockaby Erik B. Schilling John Stanturf 《Ecosystems》2008,11(8):1211-1222
Forest regrowth after cropland abandonment and urban sprawl are two counteracting processes that have influenced carbon (C)
sequestration in the southeastern United States in recent decades. In this study, we examined patterns of land-use/land-cover
change and their effect on ecosystem C storage in three west Georgia counties (Muscogee, Harris, and Meriwether) that form
a rural–urban gradient. Using time series Landsat imagery data including MSS for 1974, TM for 1983 and 1991, and ETM for 2002,
we estimate that from 1974 to 2002, urban land use in the area has increased more than 380% (that is, 184 km2). Most newly urbanized land (63%) has been converted from forestland. Conversely, cropland and pasture area has decreased
by over 59% (that is, 380 km2). Most of the cropland area was converted to forest. As a result, the net change in forest area was small over the past 29
years. Based on Landsat imagery and agricultural census records, we reconstructed an annual gridded data set of land-cover
change for the three counties for the period 1850 to 2002. These data sets were then used as input to the Terrestrial Ecosystem
Model (TEM) to simulate land-use effects on C fluxes and storage for the study area. Simulated results suggest that C uptake
by forest regrowth (approximately 23.0 g C m−2 y−1) was slightly greater than the amount of C released due to deforestation (approximately 18.4 g C m−2 y−1), thus making the three counties a weak C sink. However, the relative importance of different deforestation processes in
this area changed significantly through time. Although agricultural deforestation was generally the most important C-release
process, the amount of C release attributable to urbanization has increased over time. Since 1990, urbanization has accounted
for 29% of total C loss from the study area. We conclude that balancing urban development and forest protection is critically
important for C management and policy making in the southeastern United States. 相似文献
995.
The present work deals with the capability for producing fumonisin by Fusarium proliferatum strains isolated from asparagus in China. Fifty of F. proliferatum strains were randomly selected and incubated on cultures of maize grain and asparagus spear, respectively. Fumonisin levels
(FB1 and FB2) were determined by high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS).
The results showed that all 50 strains produced fumonisins in maize culture within a wide range of concentrations, 10–11,499 μg/g
and 2–6,598 μg/g for FB1 and FB2, respectively. On culture of asparagus spear,48 strains (96%) produced fumonisins in the range 0.2–781.6 μg/g and no detected
to 40.3 μg/g for FB1 and FB2, respectively. All of F. proliferatum strains produced much higher levels of FB1, FB2 and total fumonisins (FB1 + FB2) in maize grain culture than in asparagus spear culture. Meanwhile, fumonisin B3 (FB3) was identified in all maize culture extracts and most of asparagus spear culture extracts. This is the first study carried
out the fumonisin-producing ability of F. proliferatum strains isolated from asparagus in China. The information obtained is useful for assessing the risk of fumonisins contamination
in asparagus spear.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
996.
Recombinant industrial brewing yeast strains with ADH2 interruption using self-cloning GSH1+CUP1 cassette 总被引:2,自引:0,他引:2
Zhao-Yue Wang Jin-Jing Wang Xi-Feng Liu Xiu-Ping He & Bo-Run Zhang 《FEMS yeast research》2009,9(4):574-581
A self-cloning module for gene knock-out and knock-in in industrial brewing yeast strain was constructed that contains copper resistance and γ-glutamylcysteine synthetase gene cassette, flanked by alcohol dehydrogenase II gene ( ADH2 ) of Saccharomyces cerevisiae . The module was used to obtain recombined strains RY1 and RY2 by targeting the ADH2 locus of host Y1. RY1 and RY2 were genetically stable. PCR and enzyme activity analysis of RY1 and RY2 cells showed that one copy of ADH2 was deleted by GSH1 + CUP1 insertion, and an additional copy of wild type was still present. The fermentation ability of the recombinants was not changed after genetic modification, and a high level of glutathione (GSH) was secreted, resulting from GSH1 overexpression, which codes for γ-glutamylcysteine synthetase. A pilot-scale brewing test for RY1 and RY2 indicated that acetaldehyde content in fermenting liquor decreased by 21–22%, GSH content increased by 20–22% compared with the host, the antioxidizability of the recombinants was improved, and the sensorial evaluation was also better than that of the host. No heterologous DNA was harbored in the recombinants; therefore, they could be applied in the beer industry in terms of their biosafety. 相似文献
997.
To obtain an overall view on gene expression during the early stage (24 h) of tomato fruit in response to postharvest UV-C irradiation (4 kJ/m(2)), we performed a microarray analysis by using Affymetrix Tomato Genechip. The results showed that 274 and 403 genes were up- or down-regulated, respectively, more than two folds in postharvest tomato fruit irradiated with UV-C as compared with that in control fruit. The up-regulated genes mainly involve in signal transduction, defense response and metabolism. Conversely, genes related to cell wall disassembly, photosynthesis and lipid metabolism were generally down-regulated. These results opened ways to probe into the molecular mechanisms of the effects of postharvest UV-C irradiation on increased disease resistance, delayed softening, better quality maintenance and prolonged postharvest life in tomato fruit. 相似文献
998.
小麦中与白粉病抗性相关的两个新基因序列的克隆、特征分析及染色体定位 总被引:6,自引:0,他引:6
999.
Yang Liu Limei Ren Lingmiao Ge Qingxin Cui Xiaofang Cao Yuanyuan Hou Fang Bai Gang Bai 《Biotechnology letters》2014,36(8):1675-1680
KGLP-1, a 31-amino acid glucagon-like peptide-1 (GLP-1) analogue, has a great therapeutic potential for anti-diabetes. In this work, a strategy for expression and purification of functional KGLP-1 peptide has been established. KGLP-1 cDNA was fused with glutathione S-transferase (GST), with an enterokinase cleavage site in the fusion junction. The recombinant fusion protein GST–KGLP-1 was affinity purified via the GST-tag, and then digested with enterokinase. The resulting GST part as well as the enzymes were eliminated by ultra-filtration followed by size exclusion chromatograph. The yield of purified KGLP-1 was approximately 12.1 mg/L, with purity of 96.18 %. The recombinant KGLP-1 was shown to have similar bioactivity as native GLP-1 when evaluated in a Chinese hamster ovary cell line expressing a GLP-1 receptor-egfp reporter gene. 相似文献
1000.
Jiajia Dong Leiliang He Fei Yu Songcheng Yu Lie Liu Yongmei Tian Yilin Wang Jia Wang Lingbo Qu Yongjun Wu Runping Han 《Luminescence》2019,34(3):368-374
The occurrence of many diseases is closely related to the high expression of DNA methyltransferase 1 (DNMT1). However, most studies are focused on the detection of DNMT1 activity, a few are concerned with the detection of DNMT1 content. In this study, we developed a simple and highly sensitive chemiluminescence (CL) assay for the detection of DNMT1 content. In this method, anti‐DNMT1 monoclonal antibody was coated on a polystyrene microplate to capture DNMT1. Then anti‐DNMT1 polyclonal antibody and goat anti‐rabbit immunoglobulin G with horseradish peroxidase (IgG‐HRP) were respectively added to combine with captured DNMT1 to form a sandwich structure. Finally, the HRP could catalyze CL substrate and achieve CL signal response. Based on this novel sensitive strategy, the recovery percents were in the ranges from 71.5% to 91.0%. The precision of intra‐assays and inter‐assays were 5.45%–11.29% and 7.03%–11.25%, respectively. The method was successfully applied for the determination of DNMT1 in human serum. The detection results of serum samples showed that the proposed assay had a high correlation with enzyme‐linked immunosorbent assay (ELISA) kit. Compared with the ELISA kit (limit of detection = 0.1 ng/mL), the method has a lower limit of detection of 0.042 ng/mL. Therefore, our method has the potential for the detection of DNMT1 content in clinical diagnosis. 相似文献