首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3469篇
  免费   207篇
  国内免费   23篇
耳鼻咽喉   39篇
儿科学   186篇
妇产科学   41篇
基础医学   362篇
口腔科学   127篇
临床医学   240篇
内科学   802篇
皮肤病学   66篇
神经病学   169篇
特种医学   520篇
外科学   470篇
综合类   33篇
预防医学   165篇
眼科学   106篇
药学   172篇
中国医学   10篇
肿瘤学   191篇
  2023年   9篇
  2022年   30篇
  2021年   57篇
  2020年   40篇
  2019年   60篇
  2018年   73篇
  2017年   58篇
  2016年   69篇
  2015年   75篇
  2014年   97篇
  2013年   130篇
  2012年   109篇
  2011年   117篇
  2010年   156篇
  2009年   103篇
  2008年   119篇
  2007年   111篇
  2006年   118篇
  2005年   113篇
  2004年   111篇
  2003年   108篇
  2002年   94篇
  2001年   69篇
  2000年   103篇
  1999年   86篇
  1998年   142篇
  1997年   126篇
  1996年   130篇
  1995年   98篇
  1994年   86篇
  1993年   88篇
  1992年   43篇
  1991年   45篇
  1990年   35篇
  1989年   79篇
  1988年   72篇
  1987年   67篇
  1986年   62篇
  1985年   66篇
  1984年   39篇
  1983年   42篇
  1982年   35篇
  1981年   24篇
  1980年   38篇
  1979年   22篇
  1978年   19篇
  1977年   27篇
  1976年   28篇
  1975年   30篇
  1973年   9篇
排序方式: 共有3699条查询结果,搜索用时 15 毫秒
71.
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
72.
Pheochromocytoma is a catecholamine-producing tumor and a rare cause of hypertension. Most cases are intra-adrenal and intrapericardial pheochromocytomas are extremely uncommon. We report the case of a 46-year-old woman with a 1-year history of hypertension, in which a right atrial pheochromocytoma was detected after a hypertensive crisis. 131I-metaiodobenzylguanidine scintigraphy and magnetic resonance imaging established the diagnosis. The tumor was successfully resected using cardiopulmonary bypass and the right atrium was reconstructed using bovine pericardium.  相似文献   
73.
OBJECTIVE: To investigate the impact of official recommendations regarding the management of latent tuberculosis (TB) infection on the rate of active TB in patients receiving treatment with tumor necrosis factor (TNF) antagonists. METHODS: Data on active TB rates and on screening and treatment of latent TB infection were extracted from the BIOBADASER (Spanish Society of Rheumatology Database on Biologic Products), a registry of patients with rheumatic conditions treated with TNF antagonists. The rates of active TB among the BIOBADASER patients were compared with those in the background Spanish population, and BIOBADASER patients with rheumatoid arthritis (RA) were compared with a cohort of RA patients from the EMECAR (Morbidity and Clinical Expression of Rheumatoid Arthritis) study who were not treated with TNF antagonists and were followed up for 5 years. RESULTS: Active TB developed in 34 patients, of whom 32 started taking TNF antagonists prior to the official recommendations on latent TB infection (pre-OR) and 2 began treatment after the recommendations were issued (post-OR). All cases of TB occurred during treatment with infliximab, and 28 of these patients had RA. Pre-OR, the active TB rate in BIOBADASER patients was 20.9-fold higher than in the background Spanish population, while RA patients in the BIOBADASER had rates 22.6- and 6.2-fold higher than the background and EMECAR populations, respectively. Post-OR, 324 patients with a tuberculin skin test result > or =5 mm and/or chest radiograph findings suggestive of past TB were treated for 9 months with isoniazid (INH). Post-OR, active TB rates among the BIOBADASER patients decreased by 78% (incidence risk ratio [IRR] 0.22, 95% confidence interval [95% CI] 0.03-0.88; P = 0.008), while among RA patients in the BIOBADASER, the rate dropped by 83% and reached the EMECAR rate (IRR 1.0, 95% CI 0.02-8.2). There were no INH treatment-related hospitalizations or deaths. CONCLUSION: Strategies to treat latent TB infection that are tailored to the at-risk population can effectively and safely lessen the likelihood of active TB in patients treated with TNF antagonists.  相似文献   
74.
Introduction: Coenzyme Q10 (CoQ) deficiency syndromes comprise a growing number of genetic disorders. While primary CoQ deficiency syndromes are rare diseases, secondary deficiencies have been related to both genetic and environmental conditions, which are the main causes of biochemical CoQ deficiency. The diagnosis is the essential first step for planning future treatment strategies, as the potential treatability of CoQ deficiency is the most critical issue for the patients.

Areas covered: While the quickest and most effective tool to define a CoQ-deficient status is its biochemical determination in biological fluids or tissues, this quantification does not provide a definite diagnosis of a CoQ-deficient status nor insight about the genetic etiology of the disease. The different laboratory tests to check for CoQ deficiency are evaluated in order to choose the best diagnostic pathway for the patient.

Expert commentary: New insights are being discovered about the implication of new proteins in the intricate CoQ biosynthetic pathway. These insights reinforce the idea that next generation sequencing diagnostic strategies are the unique alternative in terms of rapid and accurate molecular diagnosis of CoQ deficiency.  相似文献   

75.
76.
Portillo  M.  Lorenzo  M. C.  Moreno  P.  García  A.  Montero  J.  Ceballos  L.  Fuentes  M. V.  Albaladejo  A. 《Lasers in medical science》2015,30(2):483-492
Lasers in Medical Science - The aim of the present study was to evaluate the influence of erbium:yttrium–aluminum–garnet (Er:YAG) and Ti:sapphire laser irradiation on the microtensile...  相似文献   
77.
Sawada  Y; Fass  DN; Katzmann  JA; Bahn  RC; Bowie  EJ 《Blood》1986,67(5):1229-1239
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels.  相似文献   
78.
79.
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号