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991.
研究腺病毒介导的低氧诱导因子=1α(HIF=1α)在急性心肌梗死(AMI)后缺血心肌中的表达变化.建立兔AMI模型,随机分为4组,分别心肌内注入腺病毒介导的HIF-1α基因(Ad-HIF-1α)、不含HIF-1α基因腺病毒颗粒(Ad--Blank)、HIF-1α核酶基因(Rz-HIF-1α),假手术组(Sham)为对照.RT-PCR和免疫组化方法分别检测HIF-1α及下游基因VEGF的mRNA和蛋白在不同时间点的表达.结果显示,AMI后1 d, HIF-1α、VEGF的mRNA和蛋白表达开始升高,7 d 达高峰,14 d、28 d逐渐下降,56 d时HIF-1αmRNA和蛋白无表达,而VEGF mRNA和蛋白仍有表达. 因此, 腺病毒介导的HIF-1α基因在缺血心肌能被有效转染并激活,其表达的时间窗为心肌缺血急性期至亚急性期.HIF-1α核酶基因能抑制HIF-1α及其下游基因的表达. 相似文献
992.
Chen CP Lin SP Tzen CY Hwu WL Chern SR Chuang CK Chiang SS Wang W 《Genetic counseling (Geneva, Switzerland)》2007,18(1):49-56
We present prenatal diagnosis of mucopolysaccharidosis type II (MPS II) (Hunter syndrome) and demonstrate marked mucopolysaccharide deposition in multiple vital organs in a 22-gestational-week affected fetus. Level II ultrasound showed cardiomegaly and hepatomegaly. Histological examinations of the fetal vital organs manifested marked mucopolysaccharide deposition. We suggest that any therapeutic approach and counseling for prenatally diagnosed MPS II should consider the early signs of in utero marked mucopolysaccharide storage. 相似文献
993.
Wickens P Kluender H Dixon J Brennan C Achebe F Bacchiocchi A Bankston D Bierer D Brands M Braun D Brown MS Chuang CY Dumas J Enyedy I Hofilena G Hong Z Housley T Jones B Khire U Kreiman C Kumarasinghe E Lowinger T Ott-Morgan R Perkins L Phillips B Schoenleber R Scott WJ Sheeler R Redman A Sun X Taylor I Wang L Wilhelm S Zhang X Zhang M Sullivan E Carter C Miglarese M Levy J 《Bioorganic & medicinal chemistry letters》2007,17(15):4378-4381
Novel anthranilamides were surprisingly found to exert additional activity on B-RAF. Corresponding thiophene, pyrazole, and thiazole core analogs were prepared as VEGFR-2 inhibitors with c-KIT, and B-RAF activity. Compounds in the phenyl, thiophene, and thiazole series are in vivo active. 相似文献
994.
995.
Wenyaw Chan Asha S. Kapadia Alice Z. Chuang 《Biometrical journal. Biometrische Zeitschrift》2001,43(1):53-62
A stochastic model describing the movements, resulting from a smoking cessation program, of a cohort of individuals from the smoking to the non‐smoking compartment is proposed. The distribution and first two moments of the number of smokers are derived. 相似文献
996.
997.
998.
A sequence-specific heparin pentasaccharide activates the serpin, antithrombin, to inhibit factor Xa through an allosteric mechanism, whereas full-length heparin chains containing this sequence further activate the serpin to inhibit thrombin by an alternative bridging mechanism. To test whether the factor Xa specificity of allosterically activated antithrombin is encoded in the serpin reactive center loop, we mutated the factor Xa-preferred P2 Gly to the thrombin-preferred P2 Pro. Kinetic studies revealed that the mutation maximally enhanced the reactivity of antithrombin with thrombin 15-fold and decreased its reactivity toward factor Xa 2-fold when the serpin was activated by heparin pentasaccharide, thereby transforming antithrombin into an allosterically activated inhibitor of both factor Xa and thrombin. Surprisingly, the enhanced thrombin specificity of the mutant antithrombin was attenuated when a full-length bridging heparin was the activator, due both to a reduced rate of covalent reaction of the mutant serpin and thrombin and preferred reaction of the mutant serpin as a substrate. These results demonstrate that the reactive center loop sequence determines the specificity of allosterically activated antithrombin for factor Xa and that the conformational flexibility of the P2 Gly may be critical for optimal bridging of antithrombin and thrombin by physiologic heparin and for preventing antithrombin from reacting as a substrate in the bridging complex. 相似文献
999.
Mei-Chin Lai Chi-Ming Shu Ming-Shing Chiou Tong-Yung Hong Ming-Jen Chuang Jack Jay Hua 《Current microbiology》1999,39(2):79-84
A new methanogenic isolate, designated as strain N2M9705 (=OCM 668), was isolated from an aquaculture fishpond near Wang-gong,
Taiwan. This strain grew on trimethylamine and methanol, but it did not catabolize H2-CO2, acetate, or formate. The cells were stained Gram-negative, nonmotile, irregular coccus 0.6–0.8 μm in diameter. Gas vacuoles
were observed and cell aggregated to form various sizes of granules. Cells grew optimally at 32°–37°C with 1% NaCl. The pH
range of growth was 6.2–7.4, and higher pH inhibited the cell growth. The cells grew well in minimal medium, but growth was
greatly stimulated by yeast extract and peptone. A comparison of 16S rDNA sequences of this organism phylogenetically related
to Methanosarcina mazei. This is the first report of methyltrophic methanogenic isolated from an aquaculture fishpond.
Received: 16 March 1999 / Accepted: 16 April 1999 相似文献
1000.
Rhodopsin's carboxy-terminal cytoplasmic tail acts as a membrane receptor for cytoplasmic dynein by binding to the dynein light chain Tctex-1. 总被引:17,自引:0,他引:17
The interaction of cytoplasmic dynein with its cargoes is thought to be indirectly mediated by dynactin, a complex that binds to the dynein intermediate chain. However, the roles of other dynein subunits in cargo binding have been unknown. Here we demonstrate that dynein translocates rhodopsin-bearing vesicles along microtubules. This interaction occurs directly between the C-terminal cytoplasmic tail of rhodopsin and Tctex-1, a dynein light chain. C-terminal rhodopsin mutations responsible for retinitis pigmentosa inhibit this interaction. Our results point to an alternative docking mechanism for cytoplasmic dynein, provide novel insights into the role of motor proteins in the polarized transport of post-Golgi vesicles, and shed light on the molecular basis of retinitis pigmentosa. 相似文献