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961.
Peng Y Shao H Ke Y Zhang P Xiang J Kaplan HJ Sun D 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(8):5006-5014
In a previous study, we demonstrated that immunization with the uveitogenic peptide interphotoreceptor retinoid-binding protein (IRBP) 1-20 induces both CD4 and CD8 uveitogenic T cells in the B6 mouse. In the current study, we determined the role of the CD8 IRBP-specific T cells in the pathogenesis of experimental autoimmune uveitis. We also determined the conditions that facilitated the activation of CD8 autoreactive T cells. Our results showed that the beta2-microglobulin(-/-) mouse had a greatly decreased susceptibility to induction of experimental autoimmune uveitis by adoptive transfer of IRBP-specific T cells from B6 mice. We also showed that unlike CD4 autoreactive T cells, activated CD8 autoreactive T cells produced only a limited number and amounts of growth factors. As a result, in the absence of exogenously supplied growth factor(s), CD8 T cell activation and expansion were aborted. However, the growth and expansion of triggered CD8 autoreactive T cells could be supported by various cytokines. In addition to factors produced by activated CD4 autoreactive T cells, factors produced by nonlymphoid cells, such as IL-7 and IL-15, and unidentified factors in the culture supernatants of astrocytes and retinal pigment epithelial cells support the CD8 autoreactive T cells as well. Finally, we showed that, although several cytokines augmented the CD8 T cell response in vitro, different cytokines appeared to act on different CD8 subsets or on different activation/differentiation phases of CD8 autoreactive T cells. As a result, cytokines, such as IL-7, supported the proliferation and survival of CD8 IRBP-specific T cells, while others had only a growth-promoting effect. 相似文献
962.
Bihl F Frahm N Di Giammarino L Sidney J John M Yusim K Woodberry T Sango K Hewitt HS Henry L Linde CH Chisholm JV Zaman TM Pae E Mallal S Walker BD Sette A Korber BT Heckerman D Brander C 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(7):4094-4101
Immunodominance is variably used to describe either the most frequently detectable response among tested individuals or the strongest response within a single individual, yet factors determining either inter- or intraindividual immunodominance are still poorly understood. More than 90 individuals were tested against 184 HIV- and 92 EBV-derived, previously defined CTL epitopes. The data show that HLA-B-restricted epitopes were significantly more frequently recognized than HLA-A- or HLA-C-restricted epitopes. HLA-B-restricted epitopes also induced responses of higher magnitude than did either HLA-A- or HLA-C-restricted epitopes, although this comparison only reached statistical significance for EBV epitopes. For both viruses, the magnitude and frequency of recognition were correlated with each other, but not with the epitope binding affinity to the restricting HLA allele. The presence or absence of HIV coinfection did not impact EBV epitope immunodominance patterns significantly. Peptide titration studies showed that the magnitude of responses was associated with high functional avidity, requiring low concentration of cognate peptide to respond in in vitro assays. The data support the important role of HLA-B alleles in antiviral immunity and afford a better understanding of the factors contributing to inter- and intraindividual immunodominance. 相似文献
963.
964.
Booth M Shaw MA Carpenter D Joseph S Kabatereine NB Kariuki HC Mwatha JK Jones FM Vennervald BJ Ouma JH Dunne DW 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(11):7112-7118
Praziquantel treatment for Schistosoma mansoni infection enhances Th2 responsiveness against parasite Ags, but also increases the variance in Ab isotype levels. This effect may arise partly from genetic heterogeneity. In this study, associations between HLA polymorphisms at three loci (HLA-DQB1, HLA-DQA1, and HLA-DRB1) and posttreatment Ig responses to S. mansoni Ags were assessed in 199 individuals aged 7-50 years from Uganda. Blood samples were assayed for IgG1, IgG4, and IgE levels against soluble worm Ag (SWA), soluble egg Ag, tegument Ag, and a recombinant tegumental Ag (rSm 22.6) 7 wk after treatment. Multivariate ANOVA analysis initially revealed associations between carriage of DRB1*13 and increased levels of IgG1, IgG4, and IgE against SWA, tegument Ag, and rSM22.6. Subsequent analysis of covariance, which controlled for correlations between isotype levels and also included pretreatment IL-4, IL-5, and IL-13 responsiveness against SWA as covariates, revealed an independent association only between DRB1*13 and a factor score summarizing IgE levels to worm-derived Ags, which was strongest in adults. A post hoc age- and sex-stratified analysis revealed lower reinfection intensities at 1 year, 22 mo, and 6 years after the first round of treatment among carriers of DRB1*13. These results indicate that genetic background has a prominent influence on the posttreatment Th2 immune response to S. mansoni Ags, as well as a downstream association with long-term reinfection levels. 相似文献
965.
966.
Paul M. McNeill Ian H. Kerridge Catherine Arciuli David A. Henry Graham J. Macdonald Richard O. Day Suzanne R. Hill 《Journal of bioethical inquiry》2006,3(3):139-148
Aim To ascertain the quantity and nature of gifts and items provided by the pharmaceutical industry in Australia to medical specialists and to consider whether these are appropriate in terms of justifiable ethical standards, empirical research and views expressed in the literature.Design and Setting Fifty-one medical Sydney specialists were asked to collect all gifts, offers, invitations, and items received from pharmaceutical companies in an eight-week period.Main Outcome Measures The items received were categorised as promotional/educational, drug samples, clinical practice aids, office gifts, personal gifts, and invitations; and were analysed in relation to the pharmaceutical industry Code of Conduct.Results A large number (mean = 42/participant) and wide range of gifts and items were received. These included promotional/educational items (mean = 21), drug samples (mean = 8), office gifts (mean = 5) and personal gifts (mean = 1), clinical aids (mean = 3), and invitations (mean = 3) to meals, meetings, and conferences. Most gifts and items complied with the Code with a few breaches including offers of entertainment (sporting event and cabaret), items of high monetary value (in competitions with prizes unrelated to medicine), unbranded gifts, and promotional documents presented as journal articles.Conclusions Medical specialists received many gifts and items from pharmaceutical companies and a few that infringed the Code current at the time of the study. The findings were considered in the light of changes that have since been made to the industry Code of Conduct and professional medical guidelines on ethical relationships between physicians and the industry. In large measure, these changes are supported although some suggestions are made for stricter standards.Competing Interest Graham Macdonald is employed by Merck Sharp & Dohme (Australia). Richard Day serves as an Advisory Board member for Merck Sharp & Dohme (Australia) (rofecoxib, etoricoxib), Merck Sharp & Dohme (Asia) (rofecoxib), Abbott Australia (adalimumab), Schering–Plough Australia (infliximab), Amgen Australia (anakinra), GlaxoSmithKline Consumer Australia (paracetamol) and, previously, Pfizer Australia (celecoxib). Any honoraria for these activities are placed in audited trust funds of St Vincent’s Hospital, Sydney, to be used to support academic activities within the Department of Clinical Pharmacology. 相似文献
967.
Saranya Limkaisang James Henry Cunnington Liew Kon Wui Baharuddin Salleh Yukio Sato Rangsi Divarangkoon Wanwisa Fangfuk Chaiwat To-anun Susumu Takamatsu 《Mycoscience》2006,47(6):327-335
To investigate the phylogenetic relationships among the powdery mildew fungi of some economically important tropical trees
belonging to Oidium subgenus Pseudoidium, we conducted molecular phylogenetic analyses using 30 DNA sequences of the rDNA internal transcribed spacer (ITS) regions
and 26 sequences of the domains D1 and D2 of the 28S rDNA obtained from the powdery mildews on Hevea brasiliensis (para rubber tree), Anacardium occidentale (cashew), Bixa orellana, Citrus spp., Mangifera indica (mango), and Acacia spp. The results indicate that the powdery mildew fungi isolated from these tropical trees are closely related to one another.
These powdery mildews are also closely related to E. alphitoides (including Erysiphe sp. on Quercus phillyraeoides). Because of the obligate biotrophic nature of the powdery mildew fungi, the relationship between powdery mildews and their
host plants is conservative. However, the present study suggests that a particular powdery mildew species has expanded its
host ranges on a wide range of the tropical trees. This article also suggests that a powdery mildew fungus distributed in
temperate regions of the Northern Hemisphere expanded its host ranges onto tropical plants and may be a good example of how
geographical and host range expansion has occurred in the Erysiphales. 相似文献
968.
hNaf1 is required for accumulation of human box H/ACA snoRNPs, scaRNPs, and telomerase 总被引:1,自引:1,他引:0
The human telomerase ribonucleoprotein particle (RNP) shares with box H/ACA small Cajal body (sca)RNPs and small nucleolar (sno)RNPs the proteins dyskerin, hGar1, hNhp2, and hNop10. How dyskerin, hGar1, hNhp2, and hNop10 assemble with box H/ACA scaRNAs, snoRNAs, and the RNA component of telomerase (hTR) in vivo remains unknown. In yeast, Naf1p interacts with H/ACA snoRNP proteins and may promote assembly of Cbf5p (the yeast ortholog of dyskerin) with nascent pre-snoRNAs. Here we show that the human HsQ96HR8 protein, thereafter termed hNaf1, can functionally replace endogenous Naf1p in yeast. HeLa hNaf1 associates with dyskerin and hNop10 as well as box H/ACA scaRNAs, snoRNAs, and hTR. Reduction of hNaf1 steady-state levels by RNAi significantly lowers accumulation of these components of box H/ACA scaRNP, snoRNP, and telomerase. hNaf1 is found predominantly in numerous discrete foci in the nucleoplasm and fails to accumulate within Cajal bodies or nucleoli. Altogether, these results suggest that hNaf1 intervenes in early assembly steps of human box H/ACA RNPs, including telomerase. 相似文献
969.
970.