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911.
Qingyu Lang Haoxing Zhang Jie Li Fang Xie Yifeng Zhang Bo Wan Long Yu 《Molecular biology reports》2010,37(3):1577-1583
The Aurora kinases play a critical role in mitosis and have been suggested as promising targets for cancer therapy due to
their frequent overexpression in a variety of tumors. Compared with established inhibitors of cell division such as the anti-tubulins,
novel agents target mitotic enzymes and show similar efficacy but with fewer side effects. Several small-molecule inhibitors
of Aurora kinases have been developed as anticancer agents, some of which have progressed to early clinical evaluation. Here
we identified 3-hydroxyflavone as a novel Aurora B inhibitor through high throughput screening. 3-Hydroxyflavone showed potent
inhibition to Aurora B with the IC50 on a nanomolar basis in the enzyme-based kinase activity assay. In the cell-based western blotting analysis, 3-hydroxyflavone
dramatically decreased the phosphorylation level of Histone H3 on the site of serine 10, demonstrating the potent endogenous
Aurora B activity inhibition in cell level. The followed cell image analysis provided the consist result. To make it clear
whether 3-hydroxyflavone inhibited Aurora B by direct binding or not, SPR analysis was carried out to measure the affinity
of interaction between Aurora B protein and 3-hydroxyflavone and the result proved the binding with high affinity. Usually
Aurora activity suppression induced cancer cell proliferation inhibition. Colony formation and cell viability with/without
treatment of 3-hydroxyflavone were measured using CCK-8. The growth suppression under 3-hydroxyflavone present and the growth
recovery after being released gave strong evidence that presence of 3-hydroxyflavone efficiently inhibited the fast growth
of cancer cells. 相似文献
912.
Zhinan Ding Jingzhang Ji Guorong Chen Hezhi Fang Shihui Yan Lijun Shen Jia Wei Kaiyan Yang Jianxin Lu Yidong Bai 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
Mitochondrial defects have been associated with various human conditions including cancers.Methods
We analyzed the mutations at the mitochondrial DNA (mtDNA) in patients with different thyroid lesions. In particular, in order to investigate if the accumulation of mtDNA mutations play a role in tumor progression, we studied the highly variable main control region of mtDNA, the displacement-loop (D-loop) in patients with non-tumor nodular goiters, with benign thyroid adenomas, and with malignant thyroid carcinomas. Total thyroid tumor or goiter samples were obtained from 101 patients, matched with nearby normal tissue and blood from the same subject.Results
Noticeably, mitochondrial microsatellite instability (mtMSI) was detected in 2 of 19 nodular goiters (10.53%), and 8 of 77 (10.39%) malignant thyroid carcinomas. In addition, 6 patients, including 5 (6.49%) with malignant thyroid carcinomas and 1 (5.26%) with nodular goiter, were found to harbor point mutations. The majority of the mutations detected were heteroplasmic.General significance
Our results indicate that mtDNA alterations in the D-loop region could happen before tumorigenesis in thyroid, and they might also accumulate during tumorigenesis. 相似文献913.
Alison J. Kriegel Yi Fang Yong Liu Zhongmin Tian Domagoj Mladinov Isaac R. Matus Xiaoqiang Ding Andrew S. Greene Mingyu Liang 《Nucleic acids research》2010,38(22):8338-8347
We reported previously an approach for identifying microRNA (miRNA)-target pairs by combining miRNA and proteomic analyses. The approach was applied in the present study to examine human renal epithelial cells treated with transforming growth factor β1 (TGFβ1), a model of epithelial–mesenchymal transition important for the development of renal interstitial fibrosis. Treatment of human renal epithelial cells with TGFβ1 resulted in upregulation of 16 miRNAs and 18 proteins and downregulation of 17 miRNAs and 16 proteins. Of the miRNAs and proteins that exhibited reciprocal changes in expression, 77 pairs met the sequence criteria for miRNA–target interactions. Knockdown of miR-382, which was up-regulated by TGFβ1, attenuated TGFβ1-induced loss of the epithelial marker E-cadherin. miR-382 was confirmed by 3′-untranslated region reporter assay to target five genes that were downregulated at the protein level by TGFβ1, including superoxide dismutase 2 (SOD2). Knockdown of miR-382 attenuated TGFβ1-induced downregulation of SOD2. Overexpression of SOD2 ameliorated TGFβ1-induced loss of the epithelial marker. The study provided experimental evidence in the form of reciprocal expression at the protein level for a large number of predicted miRNA-target pairs and discovered a novel role of miR-382 and SOD2 in the loss of epithelial characteristics induced by TGFβ1. 相似文献
914.
Chinese orchid (Cymbidium spp.) is an important potted flower with extremely high ornamental value in China. It is important to identify the genetic diversity of its germ plasma resources for development and evaluation of its cultivars. A set of 13 expressed sequence tag (EST)-derived simple sequence repeat (SSR) was used to analyze 103 cultivars of six species of Chinese orchid, namely Cymbidium goeringii, C. faberi, Cymbidium ensifolium, C. kanran, C. sinense and C. goeringii var. longibracteatum. The 13 SSR primer pairs generated a total of 168 polymorphic bands, with an average of 12.92 bands per primer and a range of 6–24 bands which clearly revealed the difference between cultivars inter- or intra-species of Chinese orchid. Cluster analysis based on UPGMA, NJ and PCoA method showed a dendrogram with three basic clusters and splitting feature of C. ensifolium and C. goeringii which partially congruent with the current taxonomic classification. 相似文献
915.
Fang Z Fang W Liu J Hong Y Peng H Zhang X Sun B Xiao Y 《Journal of microbiology and biotechnology》2010,20(9):1351-1358
The demand for beta-glucosidases insensitive to product inhibition is increasing in modern biotechnology, for these enzymes would improve the process of saccharification of lignocellulosic materials. In this study, a beta-glucosidase gene which encodes a 442-amino-acid protein was isolated from a marine microbial metagenomic library by functional screening and named as bgl1A. The protein was identified to be a member of GH1 family, and was recombinantly expressed, purified and biochemically characterized. The recombinant beta-glucosidase, Bgl1A, exhibited high level of stability in the presence of various cations and high concentrations of NaCl. Interestingly, it was activated by glucose at concentrations lower than 400 mM. With glucose further increasing, the enzyme activity of Bgl1A was gradually inhibited, but remained 50% original value in even as high as 1,000 mM glucose. These findings indicate Bgl1A might be a potent candidate for industrial applications. 相似文献
916.
Changgui Li Ming Shao Xiaoyu Cui Yingli Song Juan Li Liyong Yuan Hanhua Fang Zhenglun Liang Terry D. Cyr Fengxiang Li Xuguang Li Junzhi Wang 《Biologicals》2010,38(2):284-289
The single radial immunodiffusion (SRID) method currently used to determine the hemagglutinin (HA) content of the inactivated influenza vaccines depends on the availability of reference HA antigen and corresponding anti-serum, updated and provided annually by World Health Organization (WHO) collaborative centers. Particularly early in a pandemic outbreak, reference reagents could be the bottleneck in vaccine development and release. Therefore, other reliable tests capable of quantifying HA content could substantially shorten the time needed for vaccine formulation. Here electrophoretic separation of deglycosylated samples in conjunction with densitometry was used to quantify HA contents of H1N1 vaccine at multiple manufacturing sites. We found the overall consistency between the alternative method and traditional SRID was 88–122% in seven lots of vaccine bulks from four subtypes (types) of influenza vaccine, confirming its suitability to quantify HA content. Moreover, we used the alternative method to prepare a national HA antigen reference in China for quality control of 2009 pandemic influenza A (H1N1) vaccines prior to the arrival of the WHO SRID reference standards, subsequently confirming good agreement between both methods. The alternative method for vaccine quantification enabled the Chinese health authority to approve H1N1 vaccine 1 month earlier than otherwise possible. 相似文献
917.
Murugan Loganathan Subbiyan Maruthasalam Ling Yin Shiu Wei Ching Lien Wen Hwei Hsu Pei Fang Lee Chih Wen Yu Chin Ho Lin 《In vitro cellular & developmental biology. Plant》2010,46(3):265-273
We describe here a simple and efficient system of soybean (Glycine max L. Merrill) regeneration through direct somatic embryogenesis by using immature embryonic shoot tips (IEST) as explants.
The cultivar Kaohsiung 10 (cv. K10) used in this study did not show embryogenic response either from mature seed-derived explants
(cotyledon, embryonic tip, leaf, shoot and root) or immature cotyledons. However, it showed a high percentage (55.8%) of somatic
embryo (SEm) formation from the IEST excised 2–3 wk after flowering, thus indicating the crucial roles of type and age of
explants. The IEST put forth primary SEm after 2 mo of culturing on Murashige and Skoog (MS) medium supplemented with 6% sucrose,
164.8 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 5 mM asparagine and 684 μM glutamine. Subsequently, secondary SEm were developed
1 mo after culturing on MS medium containing 123.6 μM 2,4-D and 3% sucrose. Cotyledonary embryos were induced on MS medium
supplemented with 0.5% activated charcoal after 1 mo. The embryos were desiccated for 72–96 h on sterile Petri dishes and
regenerated on hormone-free MS medium. Plantlets with well-developed shoots and roots were obtained within 5–6 mo of culturing
of IEST. The SEm-derived plants were morphologically normal and fertile. Various parameters thought to be responsible for
efficient regeneration of soybean through somatic embryogenesis are discussed. To our knowledge, this is the first report
to employ IEST as explants for successful direct somatic embryogenesis in soybean. 相似文献
918.
Huei-Mei Hsieh Chun-Ru Lin Mei-Jane Fang Jack D. Rogers Jacques Fournier Christian Lechat Yu-Ming Ju 《Molecular phylogenetics and evolution》2010,54(3):957-969
To infer the phylogenetic relationships of Xylaria species associated with termite nests within the genus Xylaria and among genera of the subfamily Xylarioideae, β-tubulin, RPB2, and α-actin sequences of 131 cultures of 114 species from Xylaria and 11 other genera of the subfamily were analyzed. These 11 genera included Astrocystis, Amphirosellinia, Discoxylaria, Entoleuca, Euepixylon, Kretzschmaria, Nemania, Podosordaria, Poronia, Rosellinia, and Stilbohypoxylon. We showed that Xylaria species were distributed among three major clades, TE, HY, and PO, with clade TE—an equivalent of the subgenus Pseudoxylaria—encompassing exclusively those species associated with termite nests and the other two clades containing those associated with substrates other than termite nests. Xylaria appears to be a paraphyletic genus, with most of the 11 genera submerged within it. Podosordaria and Poronia, which formed a distinct clade, apparently diverged from Xylaria and the other genera early. Species of Entoleuca, Euepixylon, Nemania, and Rosellinia constituted clade NR, a major clade sister to clade PO, while those of Kretzschmaria were inserted within clade HY and those of Astrocystis, Amphirosellinia, Discoxylaria, and Stilbohypoxylon were within clade PO. 相似文献
919.
Weiguo Fang Éverton K.K. Fernandes Donald W. Roberts Michael J. Bidochka Raymond J. St. Leger 《Fungal genetics and biology : FG & B》2010,47(7):602-607
Insect pathogenic fungi including Metarhizium anisopliae offer an environmentally friendly alternative to chemical pesticides. However, their use has been limited by their relatively slow killing speed compared to chemicals and low tolerance to abiotic stresses. We report here on a class 1 laccase (MLAC1) that is involved in both virulence and tolerance to environmental stresses. Mlac1 is expressed during isotropic growth (swelling) but not during polarized growth (e.g., germ tubes and hyphae); Mlac1 is therefore expressed exclusively in the later stages of conidiation and in blastospores when M. anisopliae is living as a saprophyte. During infection processes, Mlac1 is also expressed by appressoria (infection structures) on the cuticle surface and hyphal bodies inside the insect haemocoel. Disrupting Mlac1 reduced virulence to caterpillars because of impaired appressoria and delayed post-infection events. It also produced a yellow-conidia phenotype with increased conidial susceptibility to heat shock (45 °C for 2 h) and UV-B stress. The relationship between M. anisopliae’s pigment-synthesis pathway and its adaptation to diverse natural habitats is discussed. 相似文献
920.