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991.
Cycloxygenase-2 catalyzes the synthesis of prostaglandins from arachidonic acid and this enzyme has been implicated in the
metastasis of gastric cancer. In order to examine the significance of cycloxygenase-2 (Cox-2) in the survival and proliferation
of gastric cancer cells, we have stably overexpressed an antisense Cox-2 in two gastric cancer cell lines, SGC7901 and AGS,
in order to reduce the expression of this protein. The sense and antisense Cox-2 expression vectors were created by cloning
COX-2 cDNA, in pIRES2-EGFP plasmid. Cox-2 gene expression was monitored by RT-PCR and Western blotting and the results indicated that cells with antisense
Cox-2 construct had significantly reduced Cox-2 expression in comparison to the cells that received sense-Cox-2 plasmid. Reduction
of Cox-2 expression in SGC7901 and AGS gastric cancer cells led to markedly decreased proliferation. The metastatic capability
of the two cell lines, as assessed by in vitro colony formation assay, is also significantly compromised by lowered Cox-2
expression. Thus, this study demonstrates that Cox-2 activity is necessary for the proliferation and metastasis of gastric
cancer cells. 相似文献
992.
993.
Shalchian-Tabrizi K Reier-Røberg K Ree DK Klaveness D Bråte J 《The Journal of eukaryotic microbiology》2011,58(4):315-318
The Haptophyta is a common algal group in many marine environments, but only a few species have been observed in freshwaters, with DNA sequences available from just a single species, Crysochromulina parva Lackey, 1939. Here we investigate the haptophyte diversity in a high mountain lake, Lake Finsevatn, Norway, targeting the variable V4 region of the 18S rDNA gene with PCR and 454 pyrosequencing. In addition, the freshwater diversity of Pavlovophyceae was investigated by lineage-specific PCR-primers and clone library sequencing from another Norwegian lake, Lake Svaersvann. We present new freshwater phylotypes belonging to the classes Prymnesiophyceae and Pavlovophyceae, as well as a distinct group here named HAP-1. This is the first molecular evidence of a freshwater species belonging to the class Pavlovophyceae. The HAP-1 and another recently detected marine group (i.e. HAP-2) are separated from both Pavlovophyceae and Prymnesiophyceae and may constitute new higher order taxonomic lineages. As all obtained freshwater sequences of haptophytes are distantly related to the freshwater species C. parva, the phylogeny demonstrates that haptophytes colonized freshwater on multiple independent occasions. One of these colonizations, which gave rise to HAP-1, took place very early in the history of haptophytes, before the radiation of the Prymnesiophyceae. 相似文献
994.
Brittain JM Duarte DB Wilson SM Zhu W Ballard C Johnson PL Liu N Xiong W Ripsch MS Wang Y Fehrenbacher JC Fitz SD Khanna M Park CK Schmutzler BS Cheon BM Due MR Brustovetsky T Ashpole NM Hudmon A Meroueh SO Hingtgen CM Brustovetsky N Ji RR Hurley JH Jin X Shekhar A Xu XM Oxford GS Vasko MR White FA Khanna R 《Nature medicine》2011,17(7):822-829
995.
996.
The cDNA encoding an extracellular copper zinc superoxide dismutase (LvECSOD) was cloned from the hepatopancreas of white shrimp Litopenaeus vannamei. It consisted of 915 bp nucleotides with an open reading frame corresponding to a deduced protein of 178 amino acids. The LvECSOD contains a putative signal peptide of 16 amino acids, two potential N-linked glycosylation sites (N(115)GTA and N(135)ITG) and a copper zinc superoxide dismutase family signature sequence (G(162)NAGaRvACctI(173)). It was found that four copper binding sites, four zinc binding sites and two cysteines involving in the formation of the disulfide bridge were conserved in the protein. LvECSOD shared 33-58% identity to ECSODs from other organisms. Expression analysis revealed that LvECSOD mRNA was widely distributed in all the tissues examined. When the shrimp challenged with Vibrio alginolyticus or white spot syndrome virus (WSSV), expression of LvECSOD mRNA in the hepatopancreas and hemocytes was mediated responsively. Our results suggested that LvECSOD was implicated in the immune response induced by V. alginolyticus and WSSV. 相似文献
997.
998.
Bo Zhou Dan Peng Jianzhong Lin Xingqun Huang Wusheng Peng Reqing He Ming Guo Dongying Tang Xiaoying Zhao Xuanming Liu 《Journal of Plant Biology》2011,54(1):23-32
Gibberellins (GAs) are endogenous hormones that play an important role in regulating plant stature by increasing cell division
and promoting seed germination. The GA2-oxidase gene from Arabidopsis thaliana (AtGA2ox8) was introduced into Brassica napus L. by Agrobacterium-mediated floral-dip transformation with the aim of decreasing the amount of bioactive GA and hence reduced the plant height.
As anticipated, the transgenic plant exhibited dwarf phenotype. Importantly, compared with the wild type, the transgenic plants
had delayed the seed germination, increased the chlorophyll content (28.7–36.3%) and photosynthesis capacity (14.3–18.7%)
in a single leaf. At the same time, the photosynthesis capacity of the whole plants was significantly enhanced (35.7–48.6%)
due to the extra leaves and branches. 相似文献
999.
1000.
Nunes Bdo N Ramos SB Savegnago RP Ledur MC Nones K Klein CH Munari DP 《Genetics and molecular biology》2011,34(3):429-434
The objective of this study was to estimate genetic and phenotypic correlations of body weight at 6 weeks of age (BW6), as well as final carcass yield, and moisture, protein, fat and ash contents, using data from 3,422 F2 chickens originated from reciprocal cross between a broiler and a layer line. Variance components were estimated by the REML method, using animal models for evaluating random additive genetic and fixed contemporary group (sex, hatch and genetic group) effects. The heritability estimates (h(2)) for BW6, carcass yield and percentage of carcass moisture were 0.31 ± 0.07, 0.20 ± 0.05 and 0.33 ± 0.07, respectively. The h(2) for the percentages of protein, fat and ash on a dry matter basis were 0.48 ± 0.09, 0.55 ± 0.10 and 0.36 ± 0.08, respectively. BW6 had a positive genetic correlation with fat percentage in the carcass, but a negative one with protein and ash contents. Carcass yield, thus, appears to have only low genetic association with carcass composition traits. The genetic correlations observed between traits, measured on a dry matter basis, indicated that selection for carcass protein content may favor higher ash content and a lower percentage of carcass fat. 相似文献