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   192137篇
  免费   11886篇
  国内免费   532篇
耳鼻咽喉   2524篇
儿科学   5983篇
妇产科学   4028篇
基础医学   26373篇
口腔科学   7998篇
临床医学   14423篇
内科学   42873篇
皮肤病学   4639篇
神经病学   16660篇
特种医学   6228篇
外国民族医学   26篇
外科学   24026篇
综合类   1620篇
现状与发展   1篇
一般理论   110篇
预防医学   19500篇
眼科学   3993篇
药学   11636篇
中国医学   723篇
肿瘤学   11191篇
  2023年   896篇
  2022年   929篇
  2021年   4023篇
  2020年   2670篇
  2019年   3788篇
  2018年   5274篇
  2017年   3960篇
  2016年   3766篇
  2015年   4383篇
  2014年   6044篇
  2013年   7731篇
  2012年   11953篇
  2011年   12594篇
  2010年   6452篇
  2009年   5840篇
  2008年   9970篇
  2007年   10618篇
  2006年   9787篇
  2005年   10161篇
  2004年   9500篇
  2003年   8747篇
  2002年   6794篇
  2001年   5308篇
  2000年   5285篇
  1999年   4727篇
  1998年   1809篇
  1997年   1541篇
  1996年   1490篇
  1995年   1281篇
  1994年   1225篇
  1993年   1131篇
  1992年   2913篇
  1991年   2797篇
  1990年   2584篇
  1989年   2517篇
  1988年   2298篇
  1987年   2134篇
  1986年   2017篇
  1985年   1947篇
  1984年   1445篇
  1983年   1183篇
  1982年   733篇
  1981年   713篇
  1980年   657篇
  1979年   1068篇
  1978年   730篇
  1977年   590篇
  1975年   675篇
  1974年   665篇
  1973年   679篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
2.
Jones type fifth metatarsal fractures pose a challenge to the foot and ankle surgeon, given documented high nonunion rates as well as high complication rates including hardware prominence, nerve injury, and screw breakage for existing treatment modalities including screw and plantar plate fixation. We call for the design of innovative Jones-fracture specific implants which contour to the natural curve of the fifth metatarsal. Future research should aim to expand upon existing literature for Jones fracture fixation and evaluate efficacy of novel implants which are designed to address unacceptably high complication rates for existing treatment modalities.  相似文献   
3.
4.
5.
6.
7.
We present data from patients with advanced biliary tract cancer (BTC) receiving pembrolizumab in the KEYNOTE-158 (NCT02628067; phase 2) and KEYNOTE-028 (NCT02054806; phase 1b) studies. Eligible patients aged ≥18 years from both studies had histologically/cytologically confirmed incurable BTC that progressed after standard treatment regimen(s), measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, Eastern Cooperative Oncology Group performance status 0/1, and no prior immunotherapy. Programmed death ligand 1 (PD-L1)-positive tumors were required for eligibility in KEYNOTE-028 only. Patients received pembrolizumab 200 mg every three weeks (KEYNOTE-158) or 10 mg/kg every two weeks (KEYNOTE-028) for ≤2 years. Primary efficacy endpoint was objective response rate (ORR) by RECIST v1.1. Response assessed by independent central review is reported. KEYNOTE-158 enrolled 104 patients and KEYNOTE-028 enrolled 24 patients. Median (range) follow-up was 7.5 months (0.6-34.3) in KEYNOTE-158 and 5.7 months (0.6-55.4) in KEYNOTE-028. In KEYNOTE-158, ORR was 5.8% (6/104; 95% CI, 2.1%-12.1%); median duration of response (DOR) was not reached (NR) (range, 6.2-26.6+ months). Median (95% CI) OS and PFS were 7.4 (5.5-9.6) and 2.0 (1.9-2.1) months. Among PD-L1-expressers (n = 61) and PD-L1-nonexpressers (n = 34), respectively, ORR was 6.6% (4/61) and 2.9% (1/34). In KEYNOTE-028, ORR was 13.0% (3/23; 95% CI, 2.8%-33.6%); median DOR was NR (range, 21.5-53.2+ months). Median (95% CI) OS and PFS were 5.7 (3.1-9.8) and 1.8 (1.4-3.1) months. Grade 3 to 5 treatment-related adverse events occurred in 13.5% of patients in KEYNOTE-158 (no grade 4; grade 5 renal failure, n = 1) and 16.7% in KEYNOTE-028 (no grade 4/5). In summary, pembrolizumab provides durable antitumor activity in 6% to 13% of patients with advanced BTC, regardless of PD-L1 expression, and has manageable toxicity.  相似文献   
8.
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
9.
10.
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