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131.
132.
Fertile rice plants have been regenerated from protoplasts of two japonica rice varieties (Radon and Baldo) using a protocol
initially developed for plant regeneration from protoplasts of an indica rice. Embryogenic calli were developed from immature
embryos of Radon and Baldo rice on a callus induction medium, and then used to establish cell suspensions. Protoplasts were
isolated from the cell suspensions, and cultured on a Millipore filter placed on a Kao/agarose medium that contained cell
clusters from suspensions of IR52 or IR45. The protoplasts grew vigorously on Kao medium and developed into embryogenic calli
within two to three weeks. Somatic embryo development occurred during a subsequent transfer of the calli to an LS medium for
two to three weeks. The calli were then transferred to MS or N6 plant regeneration medium, and within one to three weeks,
plants regenerated from 21 to 32% of the Radon calli, and 33 to 35% of the Baldo calli. Based upon these results and the previous
success in regenerating an indica variety from protoplasts, this procedure has great promise for regenerating a range of rice
varieties, and probably for regeneration of other monocotyledonous plants from protoplasts 相似文献
133.
Ching-San Chen Tuan-Nan Wen Hsiao-Mei Tuan 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1982,699(2):92-97
It has been previously shown that Clostridium sticklandii specifically synthesized three readily separable 75Se-labeled tRNAs, designated seleno-tRNAs I, II and III, and the partially purified seleno-tRNA II cochromatographed with l-prolyl-tRNA on DEAE-Sephadex A-50 (Chen, C.S. and Stadtman, T.C. (1980) Proc. Natl. Acad. Sci. U.S.A. 77, 1403–1407). In the present study a highly purified 75Se-labeled tRNA I was obtained by chromatography on benzoylated DEAE-cellulose, DEAE-Sephadex A-50 and Sepharose 4B. The 75Se-labeled tRNA I cochromatographed with an l-valine-accepting species on DEAE-Sephadex A-50 and Sepharose 4B. Addition of a 285-fold molar excess of unlabeled l-valine to the l-valine acceptor activity assay mixture markedly decreased the amount of l-[14C]valine bound to seleno-tRNA I. 相似文献
134.
135.
Differential response of cycling and noncycling cells to inducers of DNA synthesis and mitosis 总被引:1,自引:0,他引:1
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The objective of this study was to determine whether cells in G(0) phase are functionally distinct from those in G(1) with regard to their ability to respond to the inducers of DNA synthesis and to retard the cell cycle traverse of the G(2) component after fusion. Synchronized populations of HeLa cells in G(1) and human diploid fibroblasts in G(1) and G(0) phases were separately fused using UV-inactivated Sendai virus with HeLa cells prelabeled with [(3)H]ThdR and synchronized in S or G(2) phases. The kinetics of initiation of DNA synthesis in the nuclei of G(0) and G(1) cells residing in G(0)/S and G(1)/S dikaryons, respectively, were studied as a function of time after fusion. In the G(0)/G(2) and G(1)/G(2) fusions, the rate of entry into mitosis of the heterophasic binucleate cells was monitored in the presence of Colcemid. The effects of protein synthesis inhibition in the G(1) cells, and the UV irradiation of G(0) cells before fusion, on the rate of entry of the G(2) component into mitosis were also studied. The results of this study indicate that DNA synthesis can be induced in G(0)nuclei after fusion between G(0)- and S-phase cells, but G(0) nuclei are much slower than G(1) nuclei in responding to the inducers of DNA synthesis because the chromatin of G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells differ from G(1) cells with regard to their effects on the cell cycle progression of the G(2) nucleus into mitosis. This difference between G(0) and G(1) cells appears to depend on certain factors, probably nonhistone proteins, present in G(1) cells but absent in G(0) cells. These factors can be induced in G(0) cells by UV irradiation and inhibited in G(1) cells by cycloheximide treatment. 相似文献
136.
ZAKβ antagonizes and ameliorates the cardiac hypertrophic and apoptotic effects induced by ZAKα
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Chien‐Yao Fu Wei‐Wen Kuo Tsung‐Jung Ho Su‐Ying Wen Ling‐Chun Lin Yan‐Shen Tseng Hui‐Chuan Hung Vijaya Padma Viswanadha Chih‐Yang Huang 《Cell biochemistry and function》2016,34(8):606-612
ZAK (sterile alpha motif and leucine zipper containing kinase AZK), a serine/threonine kinase with multiple biochemical functions, has been associated with various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy. In our previous reports, we found that the activation of ZAKα signaling was critical for cardiac hypertrophy. In this study, we show that the expression of ZAKα activated apoptosis through both a FAS‐dependent pathway and a mitochondria‐dependent pathway by subsequently inducing caspase‐3. ZAKβ, an isoform of ZAKα, is dramatically expressed during cardiac hypertrophy and apoptosis. The interaction between ZAKα and ZAKβ was demonstrated here using immunoprecipitation. The results show that ZAKβ has the ability to diminish the expression level of ZAKα. These findings reveal an inherent regulatory role of ZAKβ to antagonize ZAKα and to subsequently downregulate the cardiac hypertrophy and apoptosis induced by ZAKα. 相似文献
137.
138.
ZHENG LianBin LI YongLan XI HuanJiu YU KeLi LU ShunHua SHI Rui WEN YouFeng BAO JingPing ZHANG XingHua LI YuLing REN Fu XU GuoChang 《中国科学:生命科学英文版》2015,58(2):215-217,1,3
<正>Dear Editor,Shortly after initiating the"Physical Anthropological Research on Han Chinese"research project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable 相似文献
139.
H. B. Li W. Yan G. R. Liu S. M. Wen C. J. Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(2):395-403
Tan spot, caused by Pyrenophora tritici-repentis, is a foliar disease of wheat, and it can inflict serious reduction in grain yield and quality. The bread wheat variety Ernie
was found to be immune to this disease in Australia, and its genetic control was investigated by quantitative trait loci (QTL)
analysis using a doubled haploid population. Eight QTL were identified in this population from three independent trials, and
four of them were derived from the parent Ernie. The most significant QTL was located on chromosome arm 2BS, explaining 38.2,
29.8 and 36.2% of the phenotypic variance, respectively, in these trials. The effects of the 2BS QTL were further validated
in four additional populations. The presence of this single QTL reduced disease severity by between 29.2 and 67.1% with an
average of 50.5%. The significant effects of this QTL and its consistent detection across all the trials with different genetic
backgrounds make it an ideal target for breeding programmes as well as for its further characterization. Data from this study
also showed that neither plant height nor heading date significantly affects tan spot resistance. 相似文献
140.
The NLR (nucleotide-binding domain leucine-rich repeat containing) proteins serve as regulators of inflammatory signaling pathways. NLRX1, a mitochondria-localized NLR protein, has been previously shown to negatively regulate inflammatory cytokine production activated via the MAVS-DDX58 (RIG-I) pathway. The literature also indicates that DDX58 has a negative impact upon autophagy. Consistent with the inhibitory role of NLRX1 on DDX58, our recent study indicates a role of NLRX1 in augmenting virus-induced autophagy. This effect is through its interaction with another mitochondrial protein TUFM (Tu translation elongation factor, mitochondrial, also known as EF-TuMT, COXPD4, and P43). TUFM also reduces DDX58-activated cytokines but augments autophagy. Additionally it interacts with ATG12–ATG5-ATG16L1 to form a molecular complex that modulates autophagy. The work shows that both NLRX1 and TUFM work in concert to reduce cytokine response and augment autophagy. 相似文献