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961.
Xiang-Lan Sun Sarah J. Lessard Ding An Ho-Jin Koh Hiroyasu Esumi Michael F. Hirshman Laurie J. Goodyear 《Journal of cellular biochemistry》2019,120(1):685-696
The signaling mechanisms mediating myocardial glucose transport are not fully understood. Sucrose nonfermenting AMP-activated protein kinase (AMPK)-related kinase (SNARK) is an AMPK-related protein kinase that is expressed in the heart and has been implicated in contraction-stimulated glucose transport in mouse skeletal muscle. We first determined if SNARK is phosphorylated on Thr208, a site critical for SNARK activity. Mice were treated with exercise, ischemia, submaximal insulin, or maximal insulin. Treadmill exercise slightly, but significantly increased SNARK Thr208 phosphorylation. Ischemia also increased SNARK Thr208 phosphorylation, but there was no effect of submaximal or maximal insulin. HL1 cardiomyocytes were used to overexpress wild-type (WT) SNARK and to knockdown endogenous SNARK. Overexpression of WT SNARK had no effect on ischemia-stimulated glucose transport; however, SNARK knockdown significantly decreased ischemia-stimulated glucose transport. SNARK overexpression or knockdown did not alter insulin-stimulated glucose transport or glycogen concentrations. To study SNARK function in vivo, SNARK heterozygous knockout mice (SNARK+/−) and WT littermates performed treadmill exercise. Exercise-stimulated glucose transport was decreased by ~50% in hearts from SNARK+/− mice. In summary, exercise and ischemia increase SNARK Thr208 phosphorylation in the heart and SNARK regulates exercise-stimulated and ischemia-stimulated glucose transport. SNARK is a novel mediator of insulin-independent glucose transport in the heart. 相似文献
962.
Jin Qin Yunmei Sun Shuge Liu Rui Zhao Qiyue Zhang Weijun Pang 《Journal of cellular biochemistry》2019,120(11):18751-18761
Skeletal muscle is an important and complex organ with multiple biological functions in humans and animals. Proliferation and differentiation of myoblasts are the key steps during the development of skeletal muscle. MicroRNA (miRNA) is a class of 21-nucleotide noncoding RNAs regulating gene expression by combining with the 3′-untranslated region of target messenger RNA. Many studies in recent years have suggested that miRNAs play a critical role in myogenesis. Through high-throughput sequencing, we found that miR-323-3p showed significant changes in the longissimus dorsi muscle of Rongchang pigs in different age groups. In this study, we discovered that overexpression of miR-323-3p repressed myoblast proliferation and promoted differentiation, whereas the inhibitor of miR-323-3p displayed the opposite results. Furthermore, we predicted Smad2 as the target gene of miR-323-3p and found that miR-323-3p directly modulated the expression level of Smad2. Then luciferase reporter assays verified that Smad2 was a target gene of miR-323-3p during the differentiation of myoblasts. These findings reveal that miR-323-3p is a positive regulator of myogenesis by targeting Smad2. This provides a novel mechanism of miRNAs in myogenesis. 相似文献
963.
Lifan Sun Jun Qin Wei Rong Hao Ni Hui-Shan Guo Jie Zhang 《Molecular Plant Pathology》2019,20(3):323-333
The soil-borne vascular pathogen Verticillium dahliae infects many dicotyledonous plants to cause devastating wilt diseases. During colonization, V. dahliae spores develop hyphae surrounding the roots. Only a few hyphae that adhere tightly to the root surface form hyphopodia at the infection site, which further differentiate into penetration pegs to facilitate infection. The molecular mechanisms controlling hyphopodium formation in V. dahliae remain unclear. Here, we uncovered a cellophane surface-induced gene (VdCSIN1) as a regulator of V. dahliae hyphopodium formation and pathogenesis. Deletion of VdCSIN1 compromises hyphopodium formation, hyphal development and pathogenesis. Exogenous application of cyclic adenosine monophosphate (cAMP) degradation inhibitor or disruption of the cAMP phosphodiesterase gene (VdPDEH) partially restores hyphopodium formation in the VdΔcsin1 mutant. Moreover, deletion of VdPDEH partially restores the pathogenesis of the VdΔcsin1 mutant. These findings indicate that VdCSIN1 regulates hyphopodium formation via cAMP-mediated signalling to promote host colonization by V. dahliae. 相似文献
964.
Bret Wankel Jiangyong Ouyang Xuemei Guo Krassimira Hadjiolova Jeremy Miller Yi Liao Daniel Kai Long Tham Rok Romih Leonardo R. Andrade Iwona Gumper Jean-Pierre Simon Rakhee Sachdeva Tanya Tolmachova Miguel C. Seabra Mitsunori Fukuda Nicole Schaeren-Wiemers Wan Jin Hong David D. Sabatini Xue-Ru Wu Xiangpeng Kong Gert Kreibich Michael J. Rindler Tung-Tien Sun 《Molecular biology of the cell》2016,27(10):1621-1634
Uroplakins (UPs) are major differentiation products of urothelial umbrella cells and play important roles in forming the permeability barrier and in the expansion/stabilization of the apical membrane. Further, UPIa serves as a uropathogenic Escherichia coli receptor. Although it is understood that UPs are delivered to the apical membrane via fusiform vesicles (FVs), the mechanisms that regulate this exocytic pathway remain poorly understood. Immunomicroscopy of normal and mutant mouse urothelia show that the UP-delivering FVs contained Rab8/11 and Rab27b/Slac2-a, which mediate apical transport along actin filaments. Subsequently a Rab27b/Slp2-a complex mediated FV–membrane anchorage before SNARE-mediated and MAL-facilitated apical fusion. We also show that keratin 20 (K20), which forms a chicken-wire network ∼200 nm below the apical membrane and has hole sizes allowing FV passage, defines a subapical compartment containing FVs primed and strategically located for fusion. Finally, we show that Rab8/11 and Rab27b function in the same pathway, Rab27b knockout leads to uroplakin and Slp2-a destabilization, and Rab27b works upstream from MAL. These data support a unifying model in which UP cargoes are targeted for apical insertion via sequential interactions with Rabs and their effectors, SNAREs and MAL, and in which K20 plays a key role in regulating vesicular trafficking. 相似文献
965.
A phylogenetic analysis was carried out to clarify the systematic position of Gyrocheilos and Didymocarpus, particularly the species placed in Didymocarpus sect.Heteroboea by Wang et al. Based on sequencing the internal transcribed spacer and the chloroplast spacer trnL-F, parsimony and Bayesian inference analyses were carried out using separate nuclear and chloroplast datasets, as well as a combined dataset. Our results showed that the two sections of Didymocarpus in China andGyrocheilos did not form separate monophyletic subclades, but turned up in three different places in the phylogenetic trees. In the frame of the present study, the pollen morphology of the species included in the analysis was studied. It proved inconsistent with the delimitation between Didymocarpus and Gyrocheilos. Furthermore, pollen and other morphological characters indicate that Gyrocheilos and some taxa of Didymocarpus should be placed within Didymocarpus. 相似文献
966.
967.
968.
969.
海因酶在生产手性药物中间体上具有广泛的应用价值,本文综述了海因酶的研究历史、分类与进化、酶学性质、工业应用及发展方向。 相似文献
970.
Jiashan Sun Xiurong Wang Xuexia Wen Hongmei Bao Lin Shi Qimeng Tao Yongping Jiang Xianying Zeng Xiaolong Xu Guobin Tian Shimin Zheng Hualan Chen 《PloS one》2016,11(3)
Avian influenza virus (AIV) non-structural protein 1 (NS1) is a multifunctional protein. It is present at high levels in infected cells and can be used for AIV detection and diagnosis. In this study, we generated monoclonal antibody (MAb) D7 against AIV NS1 protein by immunization of BALB/c mice with purified recombinant NS1 protein expressed in Escherichia coli. Isotype determination revealed that the MAb was IgG1/κ-type subclass. To identify the epitope of the MAb D7, the NS1 protein was truncated into a total of 225 15-mer peptides with 14 amino acid overlaps, which were spotted for a peptide microarray. The results revealed that the MAb D7 recognized the consensus DAPF motif. Furthermore, the AIV NS1 protein with the DAPF motif deletion was transiently expressed in 293T cells and failed to react with MAb D7. Subsequently, the DAPF motif was synthesized with an elongated GSGS linker at both the C- and N-termini. The MAb D7 reacted with the synthesized peptide both in enzyme-linked immunosorbent assay (ELISA) and dot-blot assays. From these results, we concluded that DAPF motif is the epitope of MAb D7. To our knowledge, this is the first report of a 4-mer epitope on the NS1 protein of AIV that can be recognized by MAb using a peptide microarray, which is able to simplify epitope identification, and that could serve as the basis for immune responses against avian influenza. 相似文献