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61.
Persistent HBV and HCV infection represent major causes of chronic liver disease with a high risk of progression to liver cirrhosis and hepatocellular carcinoma (HCC). Conventional protein-based vaccines are highly efficacious in preventing HBV infection; whereas in therapeutic settings with chronically infected patients, results have been disappointing. Prophylactic vaccination against HCV infection has not yet been achieved due to many impediments including frequent spontaneous mutations of the virus with escape from immune system control. Using animal models it has been demonstrated that DNA-based immunisation strategies may overcome this problem because of their potential to induce immunity against multiple viral epitopes. DNA-based vaccines mimic the effect of live attenuated viral vaccines, eliciting cell mediated immunity in addition to inducing humoral responses. Efficacy may further be improved by addition of DNA encoding immunomodulatory cytokines and more recently, direct genetic modulation of antigen-presenting cells, such as dendritic cells (DC), has been shown to increase antigen-specific immune responses. This review focuses on immunological aspects of chronic HBV and HCV infection and on the potential of DNA- and DC-based vaccines for the treatment of chronic viral hepatitis. 相似文献
62.
van Eeden S Offerhaus GJ Morsink FH van Rees BP Busch OR van Noesel CJ 《Virchows Archiv : an international journal of pathology》2004,444(6):590-593
Pyogenic granuloma is a lobular capillary hemangioma that mostly occurs on the skin, but it is also encountered on the mucosal surface of the oral cavity. Only a few cases in other parts of the digestive tract have been reported in Japanese patients. In this report, two Caucasian patients are described, who presented with gastrointestinal bleeding due to the presence of a pyogenic granuloma. One was located in the distal esophagus and could be treated with local excision and laser-photocoagulation therapy. The other one was located in the small intestine and was removed by surgical resection. Although extremely rare, pyogenic granuloma as a cause of gastrointestinal bleeding needs consideration. The lesion is benign, presumably reactive and can be adequately treated by excision or laser photocoagulation. Immunohistochemistry and/or polymerase chain reaction for herpesvirus 8 can reliably distinguish pyogenic granuloma from Kaposis sarcoma, an important differential diagnosis. 相似文献
63.
D. J. Schendel Ralph Oberneder Christine S. Falk Petra Jantzer Susanne Kressenstein Barbara Maget Alfons Hofstetter Gert Riethmüller Elfriede Nößner 《Journal of molecular medicine (Berlin, Germany)》1997,75(6):400-413
Renal cell carcinomas belong to the small group of tumors that are able to induce antitumor responses. Here we describe two
general types of cytotoxic effector lymphocytes that can eliminate autologous tumor cells and discuss the role that major
histocompatibility complex encoded molecules play in governing their specificities. Improved understanding of the cellular
and molecular basis of renal cell carcinoma recognition opens new avenues of research with the potential to develop better
immunotherapies for patients with metastatic disease.
Received: 24 July 1996 / Accepted: 1 November 1996 相似文献
64.
Tardivel A Tinel A Lens S Steiner QG Sauberli E Wilson A Mackay F Rolink AG Beermann F Tschopp J Schneider P 《European journal of immunology》2004,34(2):509-518
The TNF family ligand B cell-activating factor (BAFF, BLyS, TALL-1) is an essential factor for B cell development. BAFF binds to three receptors, BAFF-R, transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA), but only BAFF-R is required for successful survival and maturation of splenic B cells. To test whether the effect of BAFF is due to the up-regulation of anti-apoptotic factors, TACI-Ig-transgenic mice, in which BAFF function is inhibited, were crossed with transgenic mice expressing FLICE-inhibitory protein (FLIP) or Bcl-2 in the B cell compartment. FLIP expression did not rescue B cells, while enforced Bcl-2 expression restored peripheral B cells and the ability to mount T-dependent antibody responses. However, many B cells retained immaturity markers and failed to express normal amounts of CD21. Marginal zone B cells were not restored and the T-independent IgG3, but not IgM, response was impaired in the TACI-IgxBcl-2 mice. These results suggest that BAFF is required not only to inhibit apoptosis of maturating B cells, but also to promote differentiation events, in particular those leading to the generation of marginal zone B cells. 相似文献
65.
Gyrgy Stuber Gerhard H. Leder Walter J. Storkus Michael T. Lotze Susanne Modrow Lszl Szkely Hans Wolf Eva Klein Klas Krre George Klein 《European journal of immunology》1994,24(3):765-768
Mutations of the p53 gene are the most frequently observed genetic changes in human cancers; often leading to an overexpression of the wild-type (wt) p53 protein. Demonstrable T cell reactivity against tumor cells overexpressing wt or mutant p53-derived peptides could support the application of such epitopes in cancer immunotherapies. As the binding of peptide to MHC class I molecules is a prerequisite for antigen-specific T cell recognition, we evaluated the ability of wt and mutant p53 peptides to bind to HLA-A2.1 using two independent flow cytometry-based assay systems, the T2 major histocompatibility complex (MHC) class I peptide stabilization assay (stabilization assay) and the peptide-induced MHC class I reconstitution assay (reconstitution assay). The twenty selected wt sequences each conformed to the previously reported HLA-A2.1 peptide binding motif. Seven of the wt p53 and 2/13 mutant p53 peptides derived from the previously chosen wt peptides bound to HLA-A2.1 in both the stabilization and the reconstitution assays. An additional six wt and six mutant p53 peptides, presumably exhibiting lower affinity for HLA-A2.1, were identified only in the reconstitution assay. Those p53 peptides binding HLA-A2.1 may provide useful immunogens for the generation of HLA-A2.1-restricted cytolytic T lymphocytes in vitro and in vivo. 相似文献
66.
Susanne Ott Tommaso Costa Albert Herz 《Naunyn-Schmiedeberg's archives of pharmacology》1986,334(4):444-451
Summary Equilibrium binding isotherms of [3H]diprenorphine in membranes from NG 108-15 cells are consistent with a homogenous population of binding sites. Upon addition of Na+, Mg2+ and GTP, only a 2-fold reduction in affinity with a minor decrease in the number of sites is observed. Dissociation curves of [3H]diprenorphine, however, are clearly biphasic: in the absence of Na+, Mg2+ and GTP, 80% of the bound ligand dissociates slowly with at
1/2 of 100 min, and only 20% rapidly (t
1/2 4.5 min). In the presence of Mg2+, nearly all the binding is found in the slowly dissociating form. Upon the addition of either Na+ or GTP, 20–30% of the binding dissociates more rapidly. The rate constant of the rapidly dissociating form generated by Na+, however, is 2.5 times greater than that induced by the presence of GTP. Thus, the addition of both, Na+ and GTP, converts about 80% of the receptor into a very fast dissociating form (t
1/2 1.7 min).Exposure of intact cells to pertussis toxin (10 ng/ml) or treatment of membranes with N-ethyl maleimide (500 M), strongly reduces the proportion of the slowly dissociating component. Following these treatments, the effect of GTP is reduced or abolished, but that of Na+ remains unaffected.We conclude from these data that the effects of Na+ and GTP are not only distinct in site but also in mechanism of action and that there are three forms of opioid receptors that can be differentiated by their kinetic properties. The slowly dissociating receptor form requires a functional N unit. 相似文献
67.
Mak Susanne Hunt Matthew Boruff Jill Zaccagnini Marco Thomas Aliki 《Advances in health sciences education : theory and practice》2022,27(3):793-815
Advances in Health Sciences Education - Professional identity is believed to foster self-confidence and resilience in health care professionals. While literature exists describing professional... 相似文献
68.
Kerstin Kempf Martin Rhling Winfried Banzer Klaus Michael Braumann Martin Halle David McCarthy Hans Georg Predel Isabelle Schenkenberger Susanne Tan Hermann Toplak Aloys Berg Stephan Martin 《Nutrients》2021,13(5)
Lifestyle interventions, including meal replacement, are effective in the prevention and treatment of type-2-diabetes and obesity. Since insulin is the key weight regulator, we hypothesised that the addition of meal replacement to a lifestyle intervention reduces insulin levels more effectively than lifestyle intervention alone. In the international multicentre randomised controlled ACOORH (Almased Concept against Overweight and Obesity and Related Health Risk) trial, overweight or obese persons who meet the criteria for metabolic syndrome (n = 463) were randomised into two groups. Both groups received nutritional advice focusing on carbohydrate restriction and the use of telemonitoring devices. The intervention group substituted all three main meals per day in week 1, two meals per day in weeks 2–4, and one meal per day in weeks 5–26 with a protein-rich, low-glycaemic meal replacement. Data were collected at baseline and after 1, 3, 6 and 12 months. All datasets providing insulin data (n = 446) were included in this predefined subanalysis. Significantly higher reductions in insulin (−3.3 ± 8.7 µU/mL vs. −1.6 ± 9.8 µU/mL), weight (−6.1 ± 5.2 kg vs. −3.2 ± 4.6 kg), and inflammation markers were observed in the intervention group. Insulin reduction correlated with weight reduction and the highest amount of weight loss (−7.6 ± 4.9 kg) was observed in those participants with an insulin decrease > 2 µU/mL. These results underline the potential for meal replacement-based lifestyle interventions in diabetes prevention, and measurement of insulin levels may serve as an indicator for adherence to carbohydrate restriction. 相似文献
69.
Ezgi Dogan-Sander Roland Mergl Anja Willenberg Ronny Baber Kerstin Wirkner Steffi G. Riedel-Heller Susanne Rhr Frank M. Schmidt Georg Schomerus Christian Sander 《Nutrients》2021,13(6)
Depression and vitamin D deficiency are major public health problems. The existing literature indicates the complex relationship between depression and vitamin D. The purpose of this study was to examine whether this relationship is moderated or mediated by inflammation. A community sample (n = 7162) from the LIFE-Adult-Study was investigated, for whom depressive symptoms were assessed via the German version of CES-D scale and serum 25-hydroxyvitamin D (25(OH)D) levels and inflammatory markers (IL-6 and CRP levels, WBC count) were quantified. Mediation analyses were performed using Hayes’ PROCESS macro and regression analyses were conducted to test moderation effects. There was a significant negative correlation between CES-D and 25(OH)D, and positive associations between inflammatory markers and CES-D scores. Only WBC partially mediated the association between 25(OH)D levels and depressive symptoms both in a simple mediation model (ab: −0.0042) and a model including covariates (ab: −0.0011). None of the inflammatory markers showed a moderation effect on the association between 25(OH)D levels and depressive symptoms. This present work highlighted the complex relationship between vitamin D, depressive symptoms and inflammation. Future studies are needed to examine the effect of vitamin D supplementation on inflammation and depressive symptomatology for causality assessment. 相似文献
70.
Fabian Heinrich Kira Meißner Felicia Langenwalder Klaus Püschel Dominik Nrz Armin Hoffmann Marc Lütgehetmann Martin Aepfelbacher Eric Bibiza-Freiwald Susanne Pfefferle Axel Heinemann 《Emerging infectious diseases》2021,27(1):329
Analyses of infection chains have demonstrated that severe acute respiratory syndrome coronavirus 2 is highly transmissive. However, data on postmortem stability and infectivity are lacking. Our finding of nasopharyngeal viral RNA stability in 79 corpses showed no time-dependent decrease. Maintained infectivity is supported by virus isolation up to 35 hours postmortem. 相似文献