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981.
Effects of Commercial Harvesting on Population Characteristics and Rhizome Yield of Anemone altaica. Commercial harvesting constitutes a direct threat to numerous non–timber forest products (NTFPs), but its ecological effects have not been well documented. Anemone altaica Fisch. ex C. A. Mey, a spring ephemeral plant found in temperate forests of Eurasia, is a traditional Chinese herb. Owing to medicinal value, its rhizomes have been harvested for commercial purposes in northwestern China for many years. This paper addresses the ecological effects of commercial harvesting on A. altaica populations under different harvest intensities. The results show that size–selective harvesting of rhizomes can increase population densities by asexual propagation. Currently, two– to three–year–old individuals derived from asexual propagation are the main targets of commercial harvesting. The increased demand in recent years has resulted in earlier and more intensive harvesting activities largely impacting the natural recovery of the harvested populations. For sustainable use of this traditional medicinal species, we recommend that a periodic harvest strategy of three to four years be adopted. 相似文献
982.
Shi‐Ze Zhang Hong Huang Hong‐Wei Shan Fan Zhang Fang‐Hao Wan Tong‐Xian Liu 《Entomologia Experimentalis et Applicata》2013,147(3):293-300
Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and Pieris rapae L. (Lepidoptera: Pieridae) are serious pests of vegetables, that can occur simultaneously on a single cabbage plant [Brassica oleracea var. capitata L. (Brassicaceae)]. We determined whether pre‐feeding or infestation by B. tabaci on cabbage could induce physiological and biochemical responses of the plant against P. rapae. Developmental time, length, and weight of immature P. rapae, and defense‐related plant compounds (SOD, superoxide dismutase; POD, peroxidase; CAT, catalase; APX, ascorbate peroxidase) were measured. Development of P. rapae larvae was 21% slower on B. tabaci‐pre‐infested plants than on plants without B. tabaci infestation. When feeding on B. tabaci‐pre‐infested plants, 22% of P. rapae larvae pupated as compared with 83% on B. tabaci‐free plants. Weights of P. rapae from first to fourth instars that fed on B. tabaci‐pre‐infested plants were also reduced, whereas those of fifth instars and pupae were not. Similarly, body length of P. rapae from first to fourth instars was affected by B. tabaci pre‐infestation, whereas that of the fifth instars was not. Peroxidase and APX activities of the B. tabaci‐pre‐infested plants increased more than SOD and CAT. Peroxidase and SOD activities of B. tabaci and P. rapae co‐infested plants increased as compared with those of P. rapae‐infested plants; however, CAT and APX activities were not different between B. tabaci‐ and P. rapae‐infested plants. These results showed that B. tabaci infestation had a negative effect on P. rapae when they occurred simultaneously on the same host plant. The implications of the induced plant changes on the herbivore are discussed. 相似文献
983.
Liping Zhang Hong Zhang Yining Zhao Zhe Li Shangke Chen Jing Zhai Yunyun Chen Wei Xie Zhong Wang Qing Li Xuehua Zheng Xiaopeng Hu 《FEBS letters》2013
The antineoplastic target aldo–keto reductase family member 1B10 (AKR1B10) and the critical polyol pathway enzyme aldose reductase (AKR1B1) share high structural similarity. Crystal structures reported here reveal a surprising Trp112 native conformation stabilized by a specific Gln114-centered hydrogen bond network in the AKR1B10 holoenzyme, and suggest that AKR1B1 inhibitors could retain their binding affinities toward AKR1B10 by inducing Trp112 flip to result in an “AKR1B1-like” active site in AKR1B10, while selective AKR1B10 inhibitors can take advantage of the broader active site of AKR1B10 provided by the native Trp112 side-chain orientation. 相似文献
984.
Can-Jie Guo Qin Pan Hua Xiong Yu-Qi Qiao Zhao-Lian Bian Wei Zhong Li Sheng Hai Li Lei Shen Jing Hua Xiong Ma Jing-Yuan Fang 《FEBS letters》2013
In our previous study, miR-126 was identified as one of the leading miRNAs that is downregulated during activation of hepatic stellate cells (HSCs). However, the roles and related mechanisms of miR-126 in HSCs are not understood. In this study, we compared expression of miR-126 during HSC activation both in vitro and in vivo. We also applied RNA interference to analyze the role and mechanism of miR-126∗ in the activation of HSCs. Restoring HSCs with Lv-miR-126∗ resulted in decreased proliferation, accumulation of extracellular matrix components, and cell contraction, while also negatively regulating the vascular endothelial growth factor (VEGF) signal transduction pathways by partially targeted VEGF-A. Thus, we postulate that miR-126 may be a biological marker for the activation of HSCs, and useful for reducing intrahepatic vascular resistance and improving the sinusoidal microcirculation in chronic liver diseases. 相似文献
985.
Y. Ding W. Wu W. Wei R.E. Davis I.‐M. Lee R.W. Hammond J.P. Sheng L. Shen Y. Jiang Y. Zhao 《The Annals of applied biology》2013,162(1):131-139
Phytoplasmas are phloem‐inhabiting, cell wall‐less bacteria that cause numerous plant diseases worldwide. Plants infected by phytoplasmas often exhibit various symptoms indicative of hormonal imbalance. In this study, we investigated the effects of potato purple top (PPT) phytoplasma infection on gibberellin homeostasis in tomato plants. We found that PPT phytoplasma infection caused a significant reduction in endogenous levels of gibberellic acid (GA3). The decrease in GA3 content in diseased plants was correlated with down regulation of genes responsible for biosynthesis of bioactive GAs ( GA20ox1 and GA3ox1) and genes involved in formation of GA precursors [geranyl diphosphate synthase (GPS) and copalyldiphosphate synthase (CPS)]. Exogenous application of GA3 at 200 µmol L?1 was able to restore the GA content in infected plants to levels comparable to those in healthy controls, and to attenuate the characteristic ‘big bud’ symptoms induced by the phytoplasma. The interesting observation that PPT phytoplasma‐infected plants had prolonged low expression of key GA biosynthesis genes GA20ox1 and GA3ox1 under GA deficiency conditions led us to hypothesise that there was a diminished sensitivity of the GA metabolism feedback regulation, especially GA biosynthesis negative feedback regulation, in those affected plants, and such diminished sensitization in early stages of infection may represent a central element of the phytoplasma‐induced disruption of GA homeostasis and pathogenesis. 相似文献
986.
Chunying Jin Peng Luo Huali Zuo Jianming Chen Mingliang Chen Wei Wang 《Antonie van Leeuwenhoek》2013,103(5):989-996
A Gram-negative, oxidase-positive, facultatively anaerobic bacterium, designated strain E20121, was isolated from the digestive tract of a Japanese prawn (Marsupenaeus japonicus) collected from the coastal sea water area of Zhuhai, Guangdong province, China. The new isolate was determined to be closely related to Vibrio ponticus DSM 16217T, having 97.6 % 16S rRNA gene sequence similarity. Phylogenetic analysis based on recA, pyrH and rpoA also showed low levels of sequence similarities (72.6–96.6 %) with all species of the genus Vibrio. A multigene phylogenetic tree using concatenated sequences of the four genes (16S rRNA, rpoA, recA and pyrH) clearly showed that the new isolate is different from the currently known Vibrio species. DNA–DNA hybridization experiments revealed similarity values below 70 % with the closest related species V. ponticus DSM 16217T. Several phenotypic traits enabled the differentiation of strain E20121 from the closest phylogenetic neighbours. The DNA G+C content of strain E20121 was determined to be 47.6 mol % and the major fatty acid components identified were C16:1ω7c and/or C16:1ω6c (39.8 %), C18:1ω7c (13.6 %) and C16:0 (9.6 %). Based on genotypic, phenotypic, chemotaxonomic, phylogenetic and DNA–DNA hybridization analyses, strain E20121 is proposed to represent a novel species of the genus Vibrio for which the name Vibrio zhuhaiensis sp. nov. is proposed. The type strain is E20121T(=DSM 25602T = CCTCC AB 2011174T). 相似文献
987.
Elin Grundberg Eshwar Meduri Johanna?K. Sandling ?sa?K. Hedman Sarah Keildson Alfonso Buil Stephan Busche Wei Yuan James Nisbet Magdalena Sekowska Alicja Wilk Amy Barrett Kerrin?S. Small Bing Ge Maxime Caron So-Youn Shin the Multiple Tissue Human Expression Resource Consortium Mark Lathrop Emmanouil T. Dermitzakis Mark I. McCarthy Timothy D. Spector Jordana T. Bell Panos Deloukas 《American journal of human genetics》2013,93(5):876-890
Epigenetic modifications such as DNA methylation play a key role in gene regulation and disease susceptibility. However, little is known about the genome-wide frequency, localization, and function of methylation variation and how it is regulated by genetic and environmental factors. We utilized the Multiple Tissue Human Expression Resource (MuTHER) and generated Illumina 450K adipose methylome data from 648 twins. We found that individual CpGs had low variance and that variability was suppressed in promoters. We noted that DNA methylation variation was highly heritable (h2median = 0.34) and that shared environmental effects correlated with metabolic phenotype-associated CpGs. Analysis of methylation quantitative-trait loci (metQTL) revealed that 28% of CpGs were associated with nearby SNPs, and when overlapping them with adipose expression quantitative-trait loci (eQTL) from the same individuals, we found that 6% of the loci played a role in regulating both gene expression and DNA methylation. These associations were bidirectional, but there were pronounced negative associations for promoter CpGs. Integration of metQTL with adipose reference epigenomes and disease associations revealed significant enrichment of metQTL overlapping metabolic-trait or disease loci in enhancers (the strongest effects were for high-density lipoprotein cholesterol and body mass index [BMI]). We followed up with the BMI SNP rs713586, a cg01884057 metQTL that overlaps an enhancer upstream of ADCY3, and used bisulphite sequencing to refine this region. Our results showed widespread population invariability yet sequence dependence on adipose DNA methylation but that incorporating maps of regulatory elements aid in linking CpG variation to gene regulation and disease risk in a tissue-dependent manner. 相似文献
988.
Lin Xu Yong Zhang Zheng Shan Deng Liang Zhao Xiu Li Wei Ge Hong Wei 《Antonie van Leeuwenhoek》2013,103(3):559-565
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain. 相似文献
989.
990.
Jun Long Xulong Zhang Mingjie Wen Qingli Kong Zhe Lv Yunqing An Xiao-Qing Wei 《Biochemical and biophysical research communications》2013,430(1):364-369
Interleukin (IL)-35 is a novel heterodimeric cytokine in the IL-12 family and is composed of two subunits: Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. IL-35 is expressed in T regulatory (Treg) cells and contributes to the immune suppression function of these cells. In contrast, we found that both IL-35 subunits were expressed concurrently in most human cancer cell lines compared to normal cell lines. In addition, we found that TNF-α and IFN-γ stimulation led to increased IL-35 expression in human cancer cells. Furthermore, over-expression of IL-35 in human cancer cells suppressed cell growth in vitro, induced cell cycle arrest at the G1 phase, and mediated robust apoptosis induced by serum starvation, TNF-α, and IFN-γ stimulation through the up-regulation of Fas and concurrent down-regulation of cyclinD1, survivin, and Bcl-2 expression. In conclusion, our results reveal a novel functional role for IL-35 in suppressing cancer activity, inhibiting cancer cell growth, and increasing the apoptosis sensitivity of human cancer cells through the regulation of genes related to the cell cycle and apoptosis. Thus, this research provides new insights into IL-35 function and presents a possible target for the development of novel cancer therapies. 相似文献