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121.
Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells 下载免费PDF全文
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type. 相似文献
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Adam C. Soloff Xiangdong Liu Wentao Gao Richard D. Day Andrea Gambotto Simon M. Barratt‐Boyes 《European journal of immunology》2009,39(9):2437-2449
Heterologous adenovirus‐based vectors hold promise as preventative HIV vaccines but their capacity to induce effective T‐cell immunity in established infection has not been explored. We vaccinated rhesus macaques chronically infected with SIVmac251 and undergoing antiretroviral therapy (ART) with human adenovirus serotype 5‐based vectors expressing SIV Gag, Env, and Nef with and without IL‐15 and evaluated vaccine immunogenicity. Vaccination increased Ag‐specific T cells 20‐fold but did not expand the breadth of epitopes recognized or the quality of response, as the majority of CD8+ and CD4+ T cells produced only one cytokine irrespective of vaccination. Immunization transiently restored blood CD4+ central memory T cells (Tcm) and boosted CD4+ and CD8+ Tcm and effector cell responses but did not prevent virus rebound upon cessation of ART. Boosting with human adenovirus serotype 35‐based vectors during a second ART cycle increased Ag‐specific T cells to 50‐fold above pre‐vaccination levels and boosted CD4+ Tcm numbers but did not expand the breadth or quality of immunity or control virus levels following drug discontinuation. The number of blood CD4+ Tcm correlated positively with complexity of T‐cell responses and negatively with virus load, suggesting that more complete restoration of this subset through vaccination would be beneficial. 相似文献
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David V. Espino MD R. Lillianne Macias BA Robert C. Wood Dr PH Johanna Becho BA Melissa Talamantes MS M. Rosina Finley MD Arthur E. Hernandez PhD Rubén Martinez PhD 《Journal of the American Geriatrics Society》2010,58(7):1370-1375
Little is known about attitudes toward physician‐assisted suicide (PAS) in various ethnic groups. This study compares attitudes held by older Mexican Americans and non‐Hispanic whites and examines subject characteristics that may influence their responses. A convenience sample of 100 older Mexican Americans and 108 non‐Hispanic whites (n=208) aged 60 to 89 were recruited from four primary care community‐based practice sites in San Antonio, Texas. Interview items measured attitudes toward PAS, cognitive status, functional status, and religiosity. Older Mexican Americans (52.7%) reported stronger agreement than non‐Hispanic whites (33.7%) with PAS. Male sex (odds ratio (OR)=2.62, 95% confidence interval (CI)=1.09–6.35) predicted agreement with legalization in Mexican Americans, whereas lower religiosity scores (OR=0.84, 95% CI=0.75–0.94) were predictive of agreement in older non‐Hispanic whites. This study is the first to find positive attitudes among community‐dwelling older Mexican Americans toward PAS that are higher than those of older non‐Hispanic white adults. Sex and religious views were important determinants of positive attitudes toward PAS. Larger, more‐generalizable studies should be conducted to confirm the attitudinal patterns that have been identified in this study. 相似文献
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Background
Whereas the Scottish guidelines are audited annually, nobody evaluates guideline compliance in Germany. Thus, can external quality assurance data pursuant to section 137 of the German Social Code Book V be suitable for auditing guideline compliance?Materials and methods
From North Rhine Westphalia, a total of 48,831 cases of femoral fractures near the hip joint were evaluated. Compliance with the guidelines was determined based on preoperative hospital stay, thrombosis, and antibiotic prophylaxis. Guideline rationale was reviewed in terms of mortality and thromboembolism rate.Results
Sixty-four percent of the interventions were performed in a timely manner. Thrombosis prophylaxis was given in 99% of cases. Antibiotics were given as a single shot. There was no connection between mortality and thromboembolism rates or time to surgery.Conclusion[Überschrift]
Guideline compliance is similar in German and Scotland. The external quality assurance data are suitable for evaluating guideline compliance. The literature recommends a short time to surgery. Given the short observation period, it was not possible to demonstrate any improvement in outcomes. 相似文献129.
Gene promoter hypermethylation in ductal lavage fluid from healthy <Emphasis Type="Italic">BRCA</Emphasis>gene mutation carriers and mutation-negative controls 下载免费PDF全文
Locke I Kote-Jarai Z Fackler MJ Bancroft E Osin P Nerurkar A Izatt L Pichert G Gui GP Eeles RA 《Breast cancer research : BCR》2007,9(1):R20
Introduction
Female germline BRCA gene mutation carriers are at increased risk for developing breast cancer. The purpose of our study was to establish whether healthy BRCA mutation carriers demonstrate an increased frequency of aberrant gene promoter hypermethylation in ductal lavage (DL) fluid, compared with predictive genetic test negative controls, that might serve as a surrogate marker of BRCA1/2 mutation status and/or breast cancer risk. 相似文献130.
S. Restelli PH 《Psycho-Oncologie》2007,1(2):119-124