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   3000篇
  免费   158篇
  国内免费   13篇
耳鼻咽喉   27篇
儿科学   41篇
妇产科学   10篇
基础医学   399篇
口腔科学   173篇
临床医学   162篇
内科学   788篇
皮肤病学   15篇
神经病学   185篇
特种医学   97篇
外科学   587篇
综合类   14篇
预防医学   59篇
眼科学   23篇
药学   225篇
中国医学   5篇
肿瘤学   361篇
  2023年   28篇
  2022年   40篇
  2021年   70篇
  2020年   33篇
  2019年   63篇
  2018年   74篇
  2017年   52篇
  2016年   65篇
  2015年   53篇
  2014年   81篇
  2013年   113篇
  2012年   226篇
  2011年   236篇
  2010年   120篇
  2009年   106篇
  2008年   192篇
  2007年   212篇
  2006年   214篇
  2005年   221篇
  2004年   196篇
  2003年   200篇
  2002年   215篇
  2001年   33篇
  2000年   9篇
  1999年   30篇
  1998年   23篇
  1997年   28篇
  1996年   28篇
  1995年   25篇
  1994年   33篇
  1993年   10篇
  1992年   13篇
  1991年   19篇
  1990年   11篇
  1989年   7篇
  1988年   9篇
  1987年   7篇
  1986年   7篇
  1985年   4篇
  1984年   5篇
  1983年   6篇
  1982年   12篇
  1981年   5篇
  1980年   5篇
  1979年   4篇
  1978年   4篇
  1977年   5篇
  1976年   3篇
  1974年   3篇
  1966年   3篇
排序方式: 共有3171条查询结果,搜索用时 15 毫秒
51.
Large cell neuroendocrine carcinoma (LCNEC) of the lung is categorized as a variant of large cell carcinomas, and LCNEC tumors display biological behaviors resembling those of small cell lung carcinomas and features of high-grade neuroendocrine tumors. Because patients with LCNEC have a poor prognosis, surgery alone is not sufficient. Multimodality therapies, including adjuvant chemotherapy, appear promising for improved prognosis in patients with LCNEC. In this review article, we discuss treatment options for patients with LCNEC of the lung.  相似文献   
52.
53.
Catheter rupture after totally implantable access port (TIAP) implantation via the right internal jugular vein is thought to be very rare. We report a case of catheter rupture found 682 days after TIAP surgery in a 52-year-old woman with recurrent right breast cancer. It is possible that chronic stress at the flexure of the catheter induced by neck movements caused the catheter to rupture. Therefore, when inserting a TIAP via the right internal jugular vein, the site of venous puncture should be decided on carefully. Although a fracture of this type is rarely reported in the literature, the incidence of catheter injury of a TIAP inserted via the internal jugular vein at our institute is 1.8 %. This highlights the need to educate and caution medical staff and patients about preventing catheter fracture being caused by external factors.  相似文献   
54.
55.
56.
57.
Abstract –  Although mouthguards have been suggested as a means for preventing dental traumatic injuries, there are still some controversies over some aspects such as effectiveness in preventing concussions, material selections, method for fabrication, design, side effects and so on. The purpose of this literature review was to clarify differences in opinions with supporting evidence on these issues and find the best guidelines for promoting usage and providing mouthguards with better protective capability and fewer side effects such as difficulty in breathing and speaking.  相似文献   
58.
BACKGROUND: Concentration of carcinoembryonic antigen (CEA) is known as a marker of malignant transformation and chronic inflammation. We recently observed increased levels of serum CEA in a patient with asthma accompanied by mucoid impactions, which dramatically decreased after a sequence of bronchial washings. The present study evaluated relationships between levels of CEA, bronchial asthma and mucoid impactions. METHODS: Serum CEA concentrations were determined by chemiluminescent immunoassay (CLIA) or enzyme immunoassay in 44 subjects, comprising 9 asthmatic patients with mucoid impactions, 13 asthmatic patients without mucoid impactions, 12 patients with bronchiectasis, and 10 healthy volunteers. CEA concentrations in bronchoalveolar lavage fluid (BALF) were determined in 5 asthmatic patients with mucoid impactions and 10 healthy volunteers. RESULTS: Serum concentrations of CEA were significantly increased in asthmatic patients with mucoid impactions compared with patients without mucoid impactions, patients with bronchiectasis, or healthy volunteers (median [range], 17.3 ng/ml [2.8-28.8 ng/ml]; 3.0 ng/ml [1.5-7.1 ng/ml], 2.2 ng/ml [0.9-17.9 ng/ml], and 1.9 ng/ml [0.6-2.9 ng/ml], respectively). Concentrations of CEA in BALF were also significantly increased in asthmatic patients with mucoid impactions compared to healthy volunteers (3.2 ng/ml albumin [1.2-12.4 ng/ml albumin] vs. 0.4 ng/ml albumin [0.2-1.9 ng/ml albumin]). CONCLUSION: These findings suggest that bronchial asthma with mucoid impactions is among several pathogeneses that cause increased levels of CEA in serum and BALF.  相似文献   
59.
BACKGROUND: Cardiac sarcoidosis is frequently overlooked or misdiagnosed as idiopathic dilated cardiomyopathy (DCM), primarily because of difficulties in its diagnosis. This is a crucial issue because appropriate therapy with immunosuppressive agents can be initiated if early diagnosis is achieved. METHODS AND RESULTS: Thoracic computed tomography (CT) was retrospectively analyzed in detail with special reference to lymph node swelling (LNS) in the mediastinum of 8 patients diagnosed with idiopathic DCM who underwent left ventriculoplasty (LVP), and were later proven to have active cardiac sarcoidosis by histological evaluation of the resected myocardium. Twenty age-matched patients with idiopathic DCM who also underwent LVP served as controls. On conventional chest radiographs, none of the cardiac sarcoidosis patients exhibited lymph node involvement, including bilateral hilar lymphadenopathy. However, CT demonstrated significant mediastinal LNS in 7 (88%) of them and in only 1 (5%) of the 20 controls. There was a significant difference in the incidence of LNS in the 2 groups (p=0.00005). CONCLUSION: Evaluation of mediastinal lymphadenopathy by CT is an easy and valuable initial screening method for distinguishing cardiac sarcoidosis from idiopathic DCM.  相似文献   
60.
After the release of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines in 2001 and update in 2003, its implementation in nine Asian countries was investigated. Questionnaire surveys involving thoraco-pulmonary physicians or internists investigated the awareness and consensus of the GOLD guidelines including the care and management of chronic obstructive pulmonary disease (COPD) patients in Asian. Two surveys were conducted, in June 2002 and March 2004, through questionnaires by direct mail in Japan and face-to-face interviews in the other countries. Approximately 600 questionnaires were returned with approximately 84% awareness of the publication and its update and nearly 90% appreciated the globalization efforts. The survey revealed great variances concerning the definition of COPD, its diagnosis, and use of computed tomography. As for the implementation, the majority answered the use of the combined local and GOLD guidelines in five of nine countries surveyed, while the GOLD guidelines were implemented mainly in Korea, suggesting the influence in daily practice for care and management of COPD patients. Implication of rehabilitation in clinical practice has not been standardized despite high evidence of its advantages. Most respondents stated the necessity of developing a local or regional guideline for best practice. Our survey revealed: (i) awareness of the GOLD guidelines was high and well accepted; (ii) the possibility of developing a uniform or standard guideline in Asia is low due to local characteristics; (iii) modifications of the GOLD guidelines may be more practical; and (iv) that the multidisciplinary pulmonary rehabilitation program needs to be further activated in GOLD implementation for the Asia–Pacific region.  相似文献   
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