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991.
Boje Müller Gundula A. Noll Antonia M. Ernst Boris Rüping Sira Groscurth Richard M. Twyman Lawrence M. Kawchuk Dirk Prüfer 《Applied microbiology and biotechnology》2010,88(3):689-698
Forisomes are mechanoproteins that undergo ATP-independent contraction–expansion cycles triggered by divalent cations, pH
changes, and electrical stimuli. Although native forisomes from Medicago truncatula comprise a number of subunits encoded by separate genes, here we show that at least two of those subunits (MtSEO1 and MtSEO4)
can assemble into homomeric forisome bodies that are functionally similar to their native, multimeric counterparts. We expressed
these subunits in plants and yeast, resulting in the purification of large quantities of artificial forisomes with unique
characteristics depending on the expression platform. These artificial forisomes were able to contract and expand in vitro
like native forisomes and could respond to electrical stimulation when immobilized between interdigital transducer electrodes.
These results indicate that recombinant artificial forisomes with specific characteristics can be prepared in large amounts
and used as components of microscale and nanoscale devices. 相似文献
992.
Polymorphisms in the ovine myostatin gene (MSTN) and their association with growth and carcass traits in New Zealand Romney sheep 总被引:1,自引:0,他引:1
J. G. H. Hickford R. H. Forrest H. Zhou Q. Fang J. Han C. M. Frampton A. L. Horrell 《Animal genetics》2010,41(1):64-72
Myostatin is a regulator of myogenesis and has been implicated in the regulation of adiposity and in controlling the structure and function of tendons. Polymerase Chain Reaction Single-Stranded Conformational Polymorphism (PCR-SSCP) analysis of intron-1 was used to identify five variants (designated A-E) of the myostatin gene ( MSTN ). The effect of this genetic variation on growth and carcass traits was investigated in 517 Romney male lambs from 17 sire-lines, born on a South Island New Zealand farm. General linear mixed effect models revealed that the presence of allele A in a lamb's genotype was associated with decreased leg, loin and total yield of lean meat, whereas the presence of allele B was associated with increased loin yield and proportion loin yield (loin yield divided by total yield expressed as percentage). The effect of the number of allele copies present was investigated, and it was found that the absence of A , or the presence of two copies of B , was associated with increased mean leg yield, loin yield and total yield. Two copies of B were also associated with a decrease in proportion of shoulder yield, whereas two copies of A were associated with a decrease in proportion of loin yield. Associations with allele C were not detected. No associations of MSTN variation with birth weight, weaning weight, pre-weaning growth rate, draft age and hot carcass weight (H-W) were detected. These results suggest that variation in ovine MSTN is associated with meat production, but not birth weight or growth rate in New Zealand Romney sheep. 相似文献
993.
The effects of magnetic stimulation on spinal cord injury-induced migration of white matter astrocytes were studied using an established animal model. Ethidium bromide was injected into the dorsal spinal cord funiculus of adult Sprague-Dawley rats on the left side at T10-11. Animals then received 1.52 Tesla-pulsed magnetic stimulation for 5 min at different frequencies (0-20 Hz) for 14 consecutive days. Selected animals received the non-competitive MEK1/2 inhibitor U0126 (10 microM), prior to stimulation at 10 Hz. Lesion volumes were measured in hematoxylin/eosin-stained sections. Expression of glial fibrillary acidic protein (GFAP), microtubule associated protein-2 (MAP-2) and extra-cellular signal-regulated kinasel/2 (ERK1/2) near the epicenter of injury was examined by Western blotting with quantification using an image analysis system. Lesion volumes decreased and GFAP and p-ERK1/2 expression increased with increasing magnetic stimulation frequency (0-10 Hz). MAP-2 expression was not affected at any frequency. Pretreatment with U0126 reduced GFAP and ERK1/2 expression and increased lesion volumes in response to stimulation at 10 Hz. It is concluded that magnetic stimulation increases the migration of astrocytes to spinal cord lesions. Activation of the ERK1/2 signaling pathway is proposed to mediate astrocyte migration and glial scar formation in response to spinal cord injury. 相似文献
994.
Jin Ming Di Jun Pang Qi Peng Sun Yan Zhang You Qiang Fang Xiao Pen Liu Jian Hua Zhou Xing Xing Ruan Xin Gao 《Molecular biology reports》2010,37(4):1849-1855
CpG-oligonucleotides (CpG-ODNs), mimicking bacterial DNA, have recently been shown to stimulate prostate cancer invasion in
vitro via Toll-like receptor 9 (TLR9). Since cyclooxygenase 2 (COX-2), frequently overexpressed in multiple tumor types including
prostate cancer, is a causal factor for tumor development, invasion and metastasis, an interesting question is raised whether
TLR9 regulates COX-2 expression in prostate cancer cells. To address this question, herein we examined COX-2 expression in
PC-3 cells stimulated with different doses and time courses of CpG-ODNs. The regulatory role of NF-κB in TLR9-mediated COX-2
expression was also investigated. CpG-ODN was found to up-regulate the expression of COX-2 in PC-3 cells in a dose- and time-dependent
manner, but have little impact on COX-1 expression. Moreover, CpG-ODN also promoted nuclear translocation and activation of
NF-κB, which appeared to be required for COX-2 induction by CpG-ODN. Overall, TLR9 up-regulates COX-2 expression in prostate
cancer cells, at least partially through the activation of NF-κB, which may be implicated in tumor invasion and metastasis. 相似文献
995.
996.
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
997.
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998.
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
999.
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
1000.
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