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991.
Xiaoshu Deng Lu Gan Yan Liu Ancai Luo Liang Jin Jiao Chen Ruyu Tang Lixia Lei Jianghong Tang Jiani Zhang Zhengwu Zhao 《Genes & genomics.》2018,40(12):1351-1361
A new cold tolerant germplasm resource named glutinous rice 89-1 (Gr89-1, Oryza sativa L.) can overwinter using axillary buds, with these buds being ratooned the following year. The overwintering seedling rate (OSR) is an important factor for evaluating cold tolerance. Many quantitative trait loci (QTLs) controlling cold tolerance at different growth stages in rice have been identified, with some of these QTLs being successfully cloned. However, no QTLs conferring to the OSR trait have been located in the perennial O. sativa L. To identify QTLs associated with OSR and to evaluate cold tolerance. 286 F12 recombinant inbred lines (RILs) derived from a cross between the cold tolerant variety Gr89-1 and cold sensitive variety Shuhui527 (SH527) were used. A total of 198 polymorphic simple sequence repeat (SSR) markers that were distributed uniformly on 12 chromosomes were used to construct the linkage map. The gene ontology (GO) annotation of the major QTL was performed through the rice genome annotation project system. Three main-effect QTLs (qOSR2, qOSR3, and qOSR8) were detected and mapped on chromosomes 2, 3, and 8, respectively. These QTLs were located in the interval of RM14208 (35,160,202 base pairs (bp))–RM208 (35,520,147 bp), RM218 (8,375,236 bp)–RM232 (9,755,778 bp), and RM5891 (24,626,930 bp)–RM23608 (25,355,519 bp), and explained 19.6%, 9.3%, and 11.8% of the phenotypic variations, respectively. The qOSR2 QTL displayed the largest effect, with a logarithm of odds score (LOD) of 5.5. A total of 47 candidate genes on the qOSR2 locus were associated with 219 GO terms. Among these candidate genes, 11 were related to cell membrane, 7 were associated with cold stress, and 3 were involved in response to stress and biotic stimulus. OsPIP1;3 was the only one candidate gene related to stress, biotic stimulus, cold stress, and encoding a cell membrane protein. After QTL mapping, a total of three main-effect QTLs—qOSR2, qOSR3, and qOSR8—were detected on chromosomes 2, 3, and 8, respectively. Among these, qOSR2 explained the highest phenotypic variance. All the QTLs elite traits come from the cold resistance parent Gr89-1. OsPIP1;3 might be a candidate gene of qOSR2. 相似文献
992.
研究了鼠肝线粒体内膜体呼吸链复合体Ⅱ+Ⅲ的H~+/2e比与Δψ的相关性及其调节因素。证明:(1)用光谱法测得复合体Ⅱ+Ⅲ的电子传递与质子转移初速度的H~+/2e比值接近4,与铁氰化钾脉冲法测得的结果相同。H~+/2e随着ΔμH~+升高而逐渐下降。荧光透析法测定不同Fe~(3+)还原速率建立的不同Δψ时,证明H~+回漏对Δψ和H~+泵出速度的依赖性。讨论了呼吸链复合体Ⅱ+Ⅲ电子传递与质子转移之间的偶联以及“Redoxslip”和“protonleak”的现象。(2)抑制剂实验说明线粒体内膜中Ca~(2+)、Pi与H~+的协同运输系统对线粒体内膜H~+泵出及H~+回漏作用有一定的调控作用。 相似文献
993.
用扫描隧道显微镜观察了兔S抗原及其与鼠抗兔S抗原抗体相互作用所形成的复合物,结果表明,S抗原单体呈椭球状。其二维尺寸为7.5nm×5.3nm,且常以二聚体形式存在。抗原分别结合于抗体的二个Fab段,既可以单体结合,也可以二聚体形式结合。 相似文献
994.
采自贵州省宽阔水自然保护区的另6种虫草,它们是娄山虫草新种(CordycepsloushanensisLiang&Liusp.nov.),绿核虫草新种(CordycepsaeruginosclerotaLiang&Liusp.nov.),拟暗绿虫草(cordycepspseudoatrovirensKob.&Shim.),布氏虫草(CordycepsbrongniartiiShimazu),金针虫虫草(CordycepsagriotaKawam),和幼虫虫草[Cordycepslarvarum(Westwood)Olliff]。还报道了多颈被毛孢(HirsutellapolycollutaLiang),云南被毛孢丝梗新变种(HirsutellayunnanensisvartenuisynnemiLiangetLiuvar.nov.),巨人被毛孢(HirsutellgiganteaPetch)和枝多头霉[Polycephalomycesramosum(Peck)Mains]等几种束梗孢科的虫生真菌,及娄山拟青霉新种(PaecilomycesloushanensisLiang&Liusp.nov.)。 相似文献
995.
Direct association with and dephosphorylation of Jak2 kinase by the SH2-domain-containing protein tyrosine phosphatase SHP-1. 总被引:20,自引:5,他引:15
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H Jiao K Berrada W Yang M Tabrizi L C Platanias T Yi 《Molecular and cellular biology》1996,16(12):6985-6992
SHP-1 is an SH2-containing cytoplasmic tyrosine phosphatase that is widely distributed in cells of the hematopoietic system. SHP-1 plays an important role in the signal transduction of many cytokine receptors, including the receptor for erythropoietin, by associating via its SH2 domains to the receptors and dephosphorylating key substrates. Recent studies have suggested that SHP-1 regulates the function of Jak family tyrosine kinases, as shown by its constitutive association with the Tyk2 kinase and the hyperphosphorylation of Jak kinases in the motheaten cells that lack functional SHP-1. We have examined the interactions of SHP-1 with two tyrosine kinases activated during engagement of the erythropoietin receptor, the Janus family kinase Jak-2 and the c-fps/fes kinase. Immunoblotting studies with extracts from mouse hematopoietic cells demonstrated that Jak2, but not c-fes, was present in anti-SHP-1 immunoprecipitates, suggesting that SHP-1 selectively associates with Jak2 in vivo. Consistent with this, when SHP-1 was coexpressed with these kinases in Cos-7 cells, it associated with and dephosphorylated Jak2 but not c-fes. Transient cotransfection of truncated forms of SHP-1 with Jak2 demonstrated that the SHP-1-Jak2 interaction is direct and is mediated by a novel binding activity present in the N terminus of SHP-1, independently of SH2 domain-phosphotyrosine interaction. Such SHP-1-Jak2 interaction resulted in induction of the enzymatic activity of the phosphatase in in vitro protein tyrosine phosphatase assays. Interestingly, association of the SH2n domain of SHP-1 with the tyrosine phosphorylated erythropoietin receptor modestly potentiated but was not essential for SHP-1-mediated dephosphorylation of Jak2 and had no effect on c-fes phosphorylation. These data indicate that the main mechanism for regulation of Jak2 phosphorylation by SHP-1 involves a direct, SH2-independent interaction with Jak2 and suggest the existence of similar mechanisms for other members of the Jak family of kinases. They also suggest that such interactions may provide one of the mechanisms that control SHP-1 substrate specificity. 相似文献
996.
杜氏盐藻细胞质膜氧化还原系统与K^+吸收 总被引:3,自引:0,他引:3
杜氏盐藻(Dunaliella salina)细胞表面存在氧化NADH 与还原Fe(CN)3-6 的氧化还原系统(redoxsystem )。该系统在氧化NADH 时,抑制K+ 的吸收,在还原Fe(CN)3-6 时, 促进K+ 的吸收,当NADH 同时存在时, 促进效应最显著, 高达735% 。外源NADH 促进藻细胞的氧吸收达165% ,而使胞质pH 下降; 当NADH 存在时, Fe(CN)3-6 被快速地还原, 同时藻细胞膜外酸化程度增加。质膜H+ -ATPase和氧化还原系统的典型抑制剂都不同程度地抑制K+ 吸收; 并且钒酸盐对K+ 吸收的抑制可以被加入NADH 和Fe(CN)3-6 而部分恢复, 表明质膜H+ -ATPase和氧化还原系统共同参与了细胞K+ 的吸收过程 相似文献
997.
Sims Stephen M.; Jiao Yang; Preiksaitis Harold G. 《American journal of physiology. Cell physiology》1997,273(5):C1679
We have investigated sources ofCa2+ contributing to excitation ofhuman esophageal smooth muscle, using fura 2 to study cytosolic freeCa2+ concentration([Ca2+]i)in dispersed cells and contraction of intact muscles. Acetylcholine (ACh) caused an initial peak rise of[Ca2+]ifollowed by a plateau accompanied by reversible contraction. Removal ofextracellular Ca2+ or addition ofdihydropyridine Ca2+ channelblockers reduced the plateau phase but did not prevent contraction.Caffeine also caused elevation of[Ca2+]iand blocked responses to ACh. Undershoots of[Ca2+]iwere apparent after ACh or caffeine. Blockade of the sarcoplasmic reticular Ca2+-ATPase bycyclopiazonic acid (CPA) reduced the ACh-evoked increase of[Ca2+]iand abolished the undershoot, indicating involvement ofCa2+ stores. When contraction wasstudied in intact muscles, removal ofCa2+ or addition of nifedipinereduced, but did not abolish, carbachol (CCh)-induced contraction.Elevation of extracellular K+caused contraction that was inhibited by nifedipine, although CCh stillelicited contraction. CPA caused contraction and suppressed theCCh-induced contraction, whereas ryanodine reduced CCh-induced contraction. Our studies provide evidence that muscarinic excitation ofhuman esophagus involves both release ofCa2+ from intracellular stores andinflux of Ca2+. 相似文献
998.
多头绒泡菌染色体构建过程的形态学研究 总被引:4,自引:0,他引:4
以同步核内有丝分裂的多头绒泡菌(Physarum polycephalum)原质团为材料,在有丝分裂周期中连续取材,按常规方法制备超薄切片,在电镜下研究了染色体形态构建的整个过程。有丝分裂前期,首先是G_2期凝集的染色质块逐渐解集缩成为松散状,染色质在松散的同时逐渐改组成直径为80~150nm的松散染色线结构。接着是在松散的染色线上形成一些电子密度高的集缩区,随着集缩区的增多和扩展,染色线缩短变粗,最后形成直径300~350nm的染色体。上述两个过程各需30min左右。与上述过程同时发生的是,核仁由中央位置逐渐移向边缘,前期50min左右时在近核膜处呈团块状解体。染色体形态构建的整个过程约需1h,可分为染色质的松散改组和集缩两个连续的步骤,25~30nm染色质纤维是这一过程中能分辨的最细的形态单位。 相似文献
999.
地中海拟无枝菌酸菌U-32对硝酸盐的同化及其硝酸还原酶特性 总被引:2,自引:0,他引:2
对地中海拟无枝菌酸菌U-32菌株的研究发现,像植物及真菌硝酸还原酶一样,地中海拟无枝菌酸菌U-32硝酸还原酶也是诱导酶,其合成受铵盐阻遏,受硝酸盐的诱导。氯霉素抑制实验的结果表明,该菌株硝酸还原酶的诱导涉及到蛋白质的新合成。钼和钨的竞争实验说明U-32菌株硝酸还原酶也为一钼酶。另外在离体实验中,发现硝酸还原酶活力受到KCN和NADH的抑制,但至今未能找到其生理电子供体。此外,U-32菌株硝酸还原酶也不表现类似于植物的黄递酶等组份酶活性。该菌株硝酸还原酶和其力复霉素产量有一定相关性,但两者确切的关系尚待研究。 相似文献
1000.