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991.
Tuyen V. Ha Wonkook Kim Thang Nguyen-Tien Johanna Lindahl Hung Nguyen-Viet Nguyen Quang Thi Huy Van Nguyen Fred Unger Hu Suk Lee 《PLoS neglected tropical diseases》2021,15(6)
Japanese encephalitis (JE) is the major cause of viral encephalitis (VE) in most Asian-Pacific countries. In Vietnam, there is no nationwide surveillance system for JE due to lack of medical facilities and diagnoses. Culex tritaeniorhynchus, Culex vishnui, and Culex quinquefasciatus have been identified as the major JE vectors in Vietnam. The main objective of this study was to forecast a risk map of Culex mosquitoes in Hanoi, which is one of the most densely populated cities in Vietnam. A total of 10,775 female adult Culex mosquitoes were collected from 513 trapping locations. We collected temperature and precipitation information during the study period and its preceding month. In addition, the other predictor variables (e.g., normalized difference vegetation index [NDVI], land use/land cover and human population density), were collected for our analysis. The final model selected for estimating the Culex mosquito abundance included centered rainfall, quadratic term rainfall, rice cover ratio, forest cover ratio, and human population density variables. The estimated spatial distribution of Culex mosquito abundance ranged from 0 to more than 150 mosquitoes per 900m2. Our model estimated that 87% of the Hanoi area had an abundance of mosquitoes from 0 to 50, whereas approximately 1.2% of the area showed more than 100 mosquitoes, which was mostly in the rural/peri-urban districts. Our findings provide better insight into understanding the spatial distribution of Culex mosquitoes and its associated environmental risk factors. Such information can assist local clinicians and public health policymakers to identify potential areas of risk for JE virus. Risk maps can be an efficient way of raising public awareness about the virus and further preventive measures need to be considered in order to prevent outbreaks and onwards transmission of JE virus. 相似文献
992.
993.
Shiwen Peng Archana Monie Xiaowu Pang Chien-Fu Hung T-C Wu 《Journal of biomedical science》2011,18(1):21
Antigen-specific immunotherapy using DNA vaccines has emerged as an attractive approach for the control of tumors. Another
novel cancer therapy involves the employment of the vascular disrupting agent, 5,6-dimethylxanthenone-4-acetic acid (DMXAA).
In the current study, we aimed to test the combination of DMXAA treatment with human papillomavirus type 16 (HPV-16) E7 DNA
vaccination to enhance the antitumor effects and E7-specific CD8+ T cell immune responses in treated mice. We determined that
treatment with DMXAA generates significant therapeutic effects against TC-1 tumors but does not enhance the antigen-specific
immune responses in tumor bearing mice. We then found that combination of DMXAA treatment with E7 DNA vaccination generates
potent antitumor effects and E7-specific CD8+ T cell immune responses in the splenocytes of tumor bearing mice. Furthermore,
the DMXAA-mediated enhancement or suppression of E7-specific CD8+ T cell immune responses generated by CRT/E7 DNA vaccination
was found to be dependent on the time of administration of DMXAA and was also applicable to other antigen-specific vaccines.
In addition, we determined that inducible nitric oxide synthase (iNOS) plays a role in the immune suppression caused by DMXAA
administration before DNA vaccination. Our study has significant implications for future clinical translation. 相似文献
994.
Yeung CK Lin RC Lei F Robson C Hung le M Liang W Zhou F Han L Li SH Yang X 《Molecular phylogenetics and evolution》2011,61(1):192-202
The parrotbills (Paradoxornithidae, meaning "birds of paradox," Aves) are a group of Old World passerines with perplexing taxonomic histories due to substantial morphological and ecological variation at various levels. In this study, phylogenetic relationships of the parrotbills were reconstructed based on sequences of two mitochondrial segments and three nuclear coding regions. Three major clades with characteristic body size and plumage coloration were found in both mtDNA and nuclear gene trees. However, mtDNA phylogeny suggested that the Paradoxornithidae is paraphyletic and relationships among three major parrotbill clades were poorly resolved. On the contrary, apparent and well-supported monophyletic relationships among the three major clades of Paradoxornithidae were revealed by concatenated nuclear dataset. Since paraphyly based on mtDNA data has commonly been found within avian taxa, the conflicting phylogenetic signal between mtDNA and nuclear loci revealed in this study indicates that results obtained from mtDNA dataset alone need to be evaluated with caution. Taxonomic implications of our phylogenetic findings are discussed. These phylogenies also point out areas for future investigation regarding the rapid diversification, morphological evolution and environmental adaptation of various parrotbill species or species complexes. 相似文献
995.
996.
Adams PD Afonine PV Bunkóczi G Chen VB Echols N Headd JJ Hung LW Jain S Kapral GJ Grosse Kunstleve RW McCoy AJ Moriarty NW Oeffner RD Read RJ Richardson DC Richardson JS Terwilliger TC Zwart PH 《Methods (San Diego, Calif.)》2011,55(1):94-106
X-ray crystallography is a critical tool in the study of biological systems. It is able to provide information that has been a prerequisite to understanding the fundamentals of life. It is also a method that is central to the development of new therapeutics for human disease. Significant time and effort are required to determine and optimize many macromolecular structures because of the need for manual interpretation of complex numerical data, often using many different software packages, and the repeated use of interactive three-dimensional graphics. The Phenix software package has been developed to provide a comprehensive system for macromolecular crystallographic structure solution with an emphasis on automation. This has required the development of new algorithms that minimize or eliminate subjective input in favor of built-in expert-systems knowledge, the automation of procedures that are traditionally performed by hand, and the development of a computational framework that allows a tight integration between the algorithms. The application of automated methods is particularly appropriate in the field of structural proteomics, where high throughput is desired. Features in Phenix for the automation of experimental phasing with subsequent model building, molecular replacement, structure refinement and validation are described and examples given of running Phenix from both the command line and graphical user interface. 相似文献
997.
Huynh QK Wise SJ Koch KA Castonguay LA Reid BG Pagratis EE Koditek D Glascock CB Pitts KR Turner BA Liu X Hung M Han B Pagratis N 《Journal of biomolecular screening》2011,16(7):724-733
Transforming growth factor β (TGF-β) type I receptor (activin receptor-like kinase 5, ALK5) has been identified as a promising target for fibrotic diseases. To find a novel inhibitor of ALK5, the authors performed a high-throughput screen of a library of 420,000 compounds using dephosphorylated ALK5. From primary hits of 1521 compounds, 555 compounds were confirmed. In total, 124 compounds were then selected for follow-up based on their unique structures and other properties. Repeated concentration-response testing and final interference assays of the above compounds resulted in the discovery of a structurally novel ALK5 inhibitor (compound 8) (N-(thiophen 2-ylmethyl)-3-(3,4,5 trimethoxyphenyl)imidazo[1,2β]pyridazin 6-amine) with a low IC(50) value of 0.7 μM. Compound 8 also inhibited the TGF-β-induced nuclear translocation of SMAD with an EC(50) value of 0.8 μM. Kinetic analysis revealed that compound 8 inhibited ALK5 via mixed-type inhibition, suggesting that it may bind to ALK5 differently than other published adenosine triphosphate site inhibitors. 相似文献
998.
Hsu JM Chen CT Chou CK Kuo HP Li LY Lin CY Lee HJ Wang YN Liu M Liao HW Shi B Lai CC Bedford MT Tsai CH Hung MC 《Nature cell biology》2011,13(2):174-181
Epidermal growth factor receptor (EGFR) can undergo post-translational modifications, including phosphorylation, glycosylation and ubiquitylation, leading to diverse physiological consequences and modulation of its biological activity. There is increasing evidence that methylation may parallel other post-translational modifications in the regulation of various biological processes. It is still not known, however, whether EGFR is regulated by this post-translational event. Here, we show that EGFR Arg?1175 is methylated by an arginine methyltransferase, PRMT5. Arg?1175 methylation positively modulates EGF-induced EGFR trans-autophosphorylation at Tyr?1173, which governs ERK activation. Abolishment of Arg?1175 methylation enhances EGF-stimulated ERK activation by reducing SHP1 recruitment to EGFR, resulting in augmented cell proliferation, migration and invasion of EGFR-expressing cells. Therefore, we propose a model in which the regulatory crosstalk between PRMT5-mediated Arg?1175 methylation and EGF-induced Tyr?1173 phosphorylation attenuates EGFR-mediated ERK activation. 相似文献
999.
1000.
Ming‐Szu Hung Jian‐Hua Mao Zhidong Xu Cheng‐Ta Yang Jau‐Song Yu Chansonette Harvard Yu‐Ching Lin Dawn Therese Bravo David M. Jablons Liang You 《Journal of cellular and molecular medicine》2011,15(2):350-358
Cullin 4A (Cul4A) is important in cell survival, development, growth and the cell cycle, but its role in mesothelioma has not been studied. For the first time, we identified amplification of the Cul4A gene in four of five mesothelioma cell lines. Consistent with increased Cul4A gene copy number, we found that Cul4A protein was overexpressed in mesothelioma cells as well. Cul4A protein was also overexpressed in 64% of primary malignant pleural mesothelioma (MPM) tumours. Furthermore, knockdown of Cul4A with shRNA in mesothelioma cells resulted in up‐regulation of p21 and p27 tumour suppressor proteins in a p53‐independent manner in H290, H28 and MS‐1 mesothelioma cell lines. Knockdown of Cul4A also resulted in G0/G1 cell cycle arrest and decreased colony formation in H290, H28 and MS‐1 mesothelioma cell lines. Moreover, G0/G1 cell cycle arrest was partially reversed by siRNA down‐regulation of p21 and/or p27 in Cul4A knockdown H290 cell line. In the contrary, overexpression of Cul4A resulted in down‐regulation of p21 and p27 proteins and increased colony formation in H28 mesothelioma cell line. Both p21 and p27 showed faster degradation rates in Cul4A overexpressed H28 cell line and slower degradation rates in Cul4A knockdown H28 cell line. Our study indicates that Cul4A amplification and overexpression play an oncogenic role in the pathogenesis of mesothelioma. Thus, Cul4A may be a potential therapeutic target for MPM. 相似文献