全文获取类型
收费全文 | 19786篇 |
免费 | 1186篇 |
国内免费 | 76篇 |
专业分类
耳鼻咽喉 | 162篇 |
儿科学 | 488篇 |
妇产科学 | 492篇 |
基础医学 | 2690篇 |
口腔科学 | 378篇 |
临床医学 | 1877篇 |
内科学 | 4562篇 |
皮肤病学 | 550篇 |
神经病学 | 1736篇 |
特种医学 | 327篇 |
外科学 | 2101篇 |
综合类 | 116篇 |
一般理论 | 11篇 |
预防医学 | 2137篇 |
眼科学 | 442篇 |
药学 | 1346篇 |
中国医学 | 93篇 |
肿瘤学 | 1540篇 |
出版年
2024年 | 17篇 |
2023年 | 153篇 |
2022年 | 349篇 |
2021年 | 635篇 |
2020年 | 369篇 |
2019年 | 586篇 |
2018年 | 637篇 |
2017年 | 425篇 |
2016年 | 437篇 |
2015年 | 561篇 |
2014年 | 766篇 |
2013年 | 1047篇 |
2012年 | 1520篇 |
2011年 | 1701篇 |
2010年 | 928篇 |
2009年 | 726篇 |
2008年 | 1319篇 |
2007年 | 1336篇 |
2006年 | 1251篇 |
2005年 | 1262篇 |
2004年 | 1079篇 |
2003年 | 967篇 |
2002年 | 920篇 |
2001年 | 221篇 |
2000年 | 204篇 |
1999年 | 213篇 |
1998年 | 150篇 |
1997年 | 127篇 |
1996年 | 87篇 |
1995年 | 92篇 |
1994年 | 79篇 |
1993年 | 62篇 |
1992年 | 87篇 |
1991年 | 90篇 |
1990年 | 70篇 |
1989年 | 55篇 |
1988年 | 57篇 |
1987年 | 51篇 |
1986年 | 48篇 |
1985年 | 43篇 |
1984年 | 35篇 |
1983年 | 33篇 |
1982年 | 25篇 |
1981年 | 20篇 |
1980年 | 22篇 |
1979年 | 29篇 |
1978年 | 16篇 |
1977年 | 14篇 |
1974年 | 16篇 |
1973年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
21.
Laura Cisneros Maria-Carlota Londo?o Carmen Blasco Ramón Bataller Rosa Miquel Miquel Bruguera Pere Ginès Antoni Rimola 《Liver transplantation》2007,13(7):1017-1027
The pathogenic mechanisms of accelerated graft fibrosis in hepatitis C recurrence after liver transplantation (LT) are not well established. The aim of the study was to assess whether a greater activation of hepatic stellate cells (HSC), the major collagen-producing cells in the liver, can occur in these patients as compared to non-LT patients with chronic hepatitis C. We determined the amount of activated HSC by computer-based morphometric analysis of alpha-smooth muscle actin (alphaSMA)-positive cells and the hepatic TGFbeta(1) expression by immunohistochemistry in 46 LT patients with hepatitis C recurrence, 35 non-LT patients with chronic hepatitis C, and 16 controls. Hepatic alphaSMA and TGFbeta(1) expression was higher in LT patients with hepatitis C recurrence than in controls and was correlated with fibrosis stage and progression rate. No significant difference in alphaSMA and TGFbeta(1) expression was observed between LT and non-LT patients with hepatitis C, with the exception of a higher transforming growth factor beta-1 (TGFbeta(1)) expression in non-LT patients in the early stages of fibrosis. LT patients receiving cyclosporine (CsA) or tacrolimus (FK) had a similar fibrosis progression rate and alphaSMA and TGFbeta(1) expression. In conclusion, the accelerated fibrosis observed in LT patients with hepatitis C recurrence does not seem to be related to a greater amount of activated HSC and TGFbeta(1) expression in the grafts of these patients as compared to non-LT patients with chronic hepatitis C. In LT patients, the amount of activated HSC and TGFbeta(1) expression correlated with fibrosis stage and progression, without any apparent influence of the type of calcineurin inhibitor administered. 相似文献
22.
D-dimer has proved a useful diagnostic tool for the exclusion of deep venous thrombosis (DVT). The objective of this paper was to evaluate the diagnostic performance of a diagnostic algorithm combining clinical probability and D-dimer in outpatients receiving oral anticoagulant treatment (OAT) similar to those regularly applied to nonanticoagulated individuals. We enrolled 70 outpatients on OAT who presented with clinically suspected DVT; a standard diagnostic algorithm including clinical evaluation using the modified Wells score and a quantitative immunoturbidimetric D-dimer assay (STA Liatest D-Di; Diagnostica Stago, Asniéres sur Seine, France) was used. A 3-month follow-up period was applied for those patients in whom DVT was initially excluded. The prevalence of DVT was 18.5% (13/70); four of the diagnoses were made during the 3-month follow-up period. The sensitivity, specificity and negative predictive value of D-dimer were 69.2% (95 confidence interval, 42.4-87.3), 47.4% (95% confidence interval, 35.0-60.1) and 87.1% (95% confidence interval, 71.1-94.9), respectively. In conclusion, D-dimer is of limited value in outpatients on OAT presenting with clinically suspected DVT and should be omitted in such individuals; these patients should always undergo compression venous ultrasound, and repeat ultrasonography within 1 week might be warranted in cases with an initial negative examination. 相似文献
23.
24.
25.
Carmen Guillén Ponce María Pilar Garrido López María José Molina Garrido Gema Muñoz Molina Alfredo Carrato 《Clinical & translational oncology》2007,9(1):53-55
Pituitary metastases of solid tumours are infrequent, specially as a first manifestation. When they happen, they are usually
due to breast or lung cancer and are asymptomatic or produce diabetes insipidus. It is very strange that they produce hormonal
deficiency.
We present a case report of a bronchogenic adenocarcinoma in a 65-year-old man which began with panhypopituitarism, diabetes
insipidus and visual alterations. Magnetic resonance imaging revealed a large sellar mass, with clivus infiltration and invading
the right cavernous sinus. The biopsy result was adenocarcinoma metastases from lung cancer. 相似文献
26.
Hilda A. Perez Carmen Bracho Mirtha Romano Mercedes De la Rosa 《Parasitology research》1997,83(3):246-251
A monoclonal antibody raised by immunization of BALB/c mice with erythrocytic stages of Plasmodium vivax was shown to react with asexual erythrocytic stages of P. chabaudi. The cross-reactivity molecules are antigens of 200 and 148 kDa in P. vivax and of 190 and 70 kDa in P. chabaudi. Immunofluorescence studies of the erythrocytic stages of P. vivax and P. chabaudi indicated that expression of these antigens increased as the parasites' developed from the ring stage to the schizont stage.
In the mature trophozoites of P. chabaudi, immunoelectron microscopy revealed clusters of antigen distributed in the cytoplasm of the parasitized erythrocyte. In the
schizont, packets of antigen were found associated with the parasitophorous vacuole and the cytoplasm of the infected host
cell.
Received: 19 March 1996 / Accepted: 28 August 1996 相似文献
27.
28.
29.
30.
Alicia Gómez-Barrio David Montero-Pereira Juan J. Nogal-Ruiz José A. Escario Susana Muelas-Serrano Vladimir V. Kouznetsov Leonor Y. Vargas Méndez Juan M. Urbina Gonzáles Carmen Ochoa 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(1):73-78
A study of some antiparasitic properties of several homoallylamines and related tetrahydroquinolines and quinolines, previously
described, was carried out using in vitro activity assays against the epimastigote form of Trypanosoma cruzi and against Trichomonas vaginalis. Unspecific cytotoxicity against murine macrophages was also studied. Although the antichagasic and trichomonacidal activities
are not comparable to those of the standard drugs, nifurtimox and metronidazole, some of the compounds exhibit an interesting
specific antiparasitic activity. 相似文献