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931.
Determination of mitiglinide in rat plasma by high-performance liquid chromatography with UV detection 总被引:3,自引:0,他引:3
Lushan Y Su Z 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,834(1-2):204-207
A selective and sensitive high-performance liquid chromatography method has been developed and validated for determination of mitiglinide (MGN) in rat plasma using 2-(4-biphenylyl) propionic acid (BPA) as internal standard. Liquid-liquid extraction was used for sample preparation. Chromatographic separation was achieved on a C(18) column using acetonitrile and 0.02 mol/l KH(2)PO(4) buffer (pH 4.0) (45:55, v/v) as mobile phase delivered at 1.0 ml/min. The UV detector was set at 210 nm. The assay was linear over the range 0.1-20 microg/ml for MGN. The average extraction recoveries of MGN and BPA from rat plasma were 98.6 and 97.4%, respectively. The developed method has been applied to the pharmacokinetic study of MGN in rats. 相似文献
932.
Vibrio cholerae can be differentiated into epidemic and non-epidemic strains by sorbitol fermentation speed, but little research has been done on its mechanisms. In this study, we investigated differential protein expression of the two strains in response to sorbitol metabolism. V. cholerae strains were cultured in media with and without sorbitol, respectively. Proteins were separated by 2-DE, and those that showed different expression in the two media were identified by MALDI-TOF MS. Fifteen proteins in epidemic strains and 11 proteins in non-epidemic strains showed a different expression in sorbitol medium. Among them, 4 proteins were common to epidemic and non-epidemic strains. Gene sequence analysis showed that some mutations occurred in these proteins between the two strains. Potential functions of these proteins included sugar uptake, amino acid uptake, electron transport, sulfate and thiosulfate transport. 相似文献
933.
春化作用在控制高等植物开花中起着重要的作用。本文综述了近年来以拟南芥(Arabidopsis thaliana)和冬小麦(Triticum aestivum)为主要研究对象进行的有关春化作用分子机制的研究; 概括和分析了已经分离得到的与春化有关的基因的功能及其调控方式以及各基因间的相互作用。 相似文献
934.
Exchange of Proton and Major Elements in Two-Layer Canopies Under Acid Rain in a Subtropical Evergreen Forest in Central-South China 总被引:1,自引:0,他引:1
Gong Zhang Guang-Ming Zeng Yi-Min Jiang Chun-Yan DU Guo-He Huang Mei Zeng Xiao-Kang Su Ren-Jun Xiang 《植物学报(英文版)》2006,48(10):1154-1162
Canopy exchanges of H^+ and N (NH4^+-N, NO3^--N) and other major ions were evaluated and quantified In twolayer canopies based on throughfall measurements in Shaoshan Forest during the period 2000-2002, central-south China, The collected annual rainfall, throughfall, and sub-throughfall were 1 401, 1 191, and 1 084 mm/year, respectively. Fifteen percent and 8% of rainfall (or 9% of throughfall) were intercepted by the top canopy and sub-canopy layers, respectively, The foliar leaching of base cations from the top canopy was significantly higher than that from the sub-canopy, and the latter accounted for 25% of the former. The uptake of H^+ and NH4^+ was significantly higher in the top canopy than in the sub-canopy, indicating that the canopy buffering capacity in the top canopy was stronger than the sub-canopy; Mg^2+ can be absorbed from water flux on the sub-canopy foliar surfaces to compensate for the Mg deficit in the forest soil during the growing season, 相似文献
935.
Hui-Cai Zeng Liu-Hong Deng Chun-Fa Zhang 《植物学报(英文版)》2006,48(8):952-957
In an attempt to isolate and identify the target genes relevant to salt tolerance in a mangrove plant (Sesuvium portulacastrum L.), a subtracted cDNA library was constructed via suppressive subtractive hybridization (SSH), in which the poly(A)+RNA isolated from salt-tolerant S. portulacastrum leaves was used as a tester, whereas the driver was poly(A)+RNA, derived from salt-sensitive S. portulacastrum leaves. Screening of this subtracted cDNA library revealed five clones, of which the expression levels in the salt-tolerant plant were markedly higher than those observed in the salt-sensitive plant, indicating that these candidate clones may be involved in salt-tolerance pathways. Among the clones isolated, P66, P175, and P233 are novel because no significant similarity was obtained upon alignment with the GenBank database. Clone P89 demonstrated high homology with NADPH of Arabidopsis thaliana, whereas clone P152 was highly homologous with the gene encoding late embryogenesis abundant (LEA) protein of A. thaliana. The full-length gene of clone P152, with a predicated 344 amino acid residues, was shown to bear LEA-2 domains, a signature motif for proteins that have been enriched under salty and drought conditions. It is thus implied that clone P152 would be a salt-tolerance gene of S. portulacastrum. In addition, we have also developed a strategy for the extraction of total RNA from mangrove plants. 相似文献
936.
Callister SJ Dominguez MA Nicora CD Zeng X Tavano CL Kaplan S Donohue TJ Smith RD Lipton MS 《Journal of proteome research》2006,5(8):1940-1947
The high-throughput accurate mass and time (AMT) tag proteomic approach was utilized to characterize the proteomes for cytoplasm, cytoplasmic membrane, periplasm, and outer membrane fractions from aerobic and photosynthetic cultures of the gram-nagtive bacterium Rhodobacter sphaeroides 2.4.1. In addition, we analyzed the proteins within purified chromatophore fractions that house the photosynthetic apparatus from photosynthetically grown cells. In total, 8,300 peptides were identified with high confidence from at least one subcellular fraction from either cell culture. These peptides were derived from 1,514 genes or 35% percent of proteins predicted to be encoded by the genome. A significant number of these proteins were detected within a single subcellular fraction and their localization was compared to in silico predictions. However, the majority of proteins were observed in multiple subcellular fractions, and the most likely subcellular localization for these proteins was investigated using a Z-score analysis of estimated protein abundance along with clustering techniques. Good (81%) agreement was observed between the experimental results and in silico predictions. The AMT tag approach provides localization evidence for those proteins that have no predicted localization information, those annotated as putative proteins, and/or for those proteins annotated as hypothetical and conserved hypothetical. 相似文献
937.
Wolff S Otto A Albrecht D Zeng JS Büttner K Glückmann M Hecker M Becher D 《Molecular & cellular proteomics : MCP》2006,5(7):1183-1192
The proteome of exponentially growing Bacillus subtilis cells was dissected by the implementation of shotgun proteomics and a semigel-based approach for a particular exploration of membrane proteins. The current number of 745 protein identifications that was gained by the use of two-dimensional gel electrophoresis could be increased by 473 additional proteins. Therefore, almost 50% of the 2500 genes expressed in growing B. subtilis cells have been demonstrated at the protein level. In terms of exploring cellular physiology and adaptation to environmental changes or stress, proteins showing an alteration in expression level are of primary interest. The large number of vegetative proteins identified by gel-based and gel-free approaches is a good starting point for comparative physiological investigations. For this reason a gel-free quantitation with the recently introduced iTRAQ (isobaric tagging for relative and absolute quantitation) reagent technique was performed to investigate the heat shock response in B. subtilis. A comparison with gel-based data showed that both techniques revealed a similar level of up-regulation for proteins belonging to well studied heat hock regulons (SigB, HrcA, and CtsR). However, additional datasets have been obtained by the gel-free approach indicating a strong heat sensitivity of specific enzymes involved in amino acid synthesis. 相似文献
938.
939.
Tao Wang Jinhua Wu Wei Dong Mengwen Wang Xiaodan Zhong Wenjun Zhang Lei Dai Yang Xie Yujian Liu Xingwei He Wanjun Liu Thati Madhusudhan Hesong Zeng Hongjie Wang 《International journal of biological sciences》2021,17(12):2984
Background: Chronic diabetes accelerates vascular dysfunction often resulting in cardiomyopathy but underlying mechanisms remain unclear. Recent studies have shown that the deregulated unfolded protein response (UPR) dependent on highly conserved IRE1α-spliced X-box- binding protein (XBP1s) and the resulting endoplasmic reticulum stress (ER-Stress) plays a crucial role in the occurrence and development of diabetic cardiomyopathy (DCM). In the present study, we determined whether targeting MAPK/ERK pathway using MEK inhibitor U0126 could ameliorate DCM by regulating IRE1α-XBP1s pathway.Method: Three groups of 8-week-old C57/BL6J mice were studied: one group received saline injection as control (n=8) and two groups were made diabetic by streptozotocin (STZ) (n=10 each). 18 weeks after STZ injection and stable hyperglycemia, one group had saline treatment while the second group was treated with U0126 (1mg/kg/day), 8 weeks later, all groups were sacrificed. Cardiac function/histopathological changes were determined by echocardiogram examination, Millar catheter system, hematoxylin-eosin staining and western blot analysis. H9C2 cardiomyocytes were employed for in vitro studies.Results: Echocardiographic, hemodynamic and histological data showed overt myocardial hypertrophy and worsened cardiac function in diabetic mice. Chronic diabetic milieu enhanced SUMOylation and impaired nuclear translocation of XBP1s. Intriguingly, U0126 treatment significantly ameliorated progression of DCM, and this protective effect was achieved through enriching XBP1s'' nuclear accumulation. Mechanistically, U0126 inhibited XBP1s'' phosphorylation on S348 and SUMOylation on K276 promoting XBP1s'' nuclear translocation. Collectively, these results identify that MEK inhibition restores XBP1s-dependent UPR and protects against diabetes-induced cardiac remodeling.Conclusion: The current study identifies previously unknown function of MEK/ERK pathway in regulation of ER-stress in DCM. U0126 could be a therapeutic target for the treatment of DCM. 相似文献
940.
Some fungi are able to control and remediate arsenic (As)-contaminated soil, sediment, or water. Here, we investigate potential
accumulation and volatilisation of As by three fungi strains. Results indicated that the highest level of As was accumulated
by Penicillin
janthinellum with 39.54 μg after 10 days in the culture system amended with 2,500 μg As(V), which represents 50 mg/l As. Fusarium
oxysporum showed the highest amount of volatilised As with 304.06 μg after 15 days. The As content in the treated system (filter paper + As + fungi)
was significantly higher than that in the control (filter paper + As; filter paper + fungi; filter paper). Trichoderma asperellum and F. oxysporum showed superior abilities for the absorption of extracellular As and accumulation of intracellular As, which accounted for
82.2 and 63.4% of the total accumulated As, respectively. However, P. janthinellum presented an equal distribution of intracellular and extracellular As. Scanning electron microscope (SEM) analysis suggested
that little impact on mycelium growth of the three fungal strains was seen after exposure to 50 mg/l As(V) for 5 days, while
the growth of fungi in the control was inhibited. The present results demonstrate that P.
janthinellum, F.
oxysporum, and T. asperellum would be expected to tackle As-contaminated environments. 相似文献