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   1294340篇
  免费   89270篇
  国内免费   1544篇
耳鼻咽喉   16745篇
儿科学   41684篇
妇产科学   35520篇
基础医学   192306篇
口腔科学   35303篇
临床医学   120583篇
内科学   251894篇
皮肤病学   27532篇
神经病学   103872篇
特种医学   47491篇
外国民族医学   265篇
外科学   181566篇
综合类   26172篇
现状与发展   3篇
一般理论   588篇
预防医学   107366篇
眼科学   28414篇
药学   94164篇
  39篇
中国医学   2051篇
肿瘤学   71596篇
  2019年   10729篇
  2018年   13946篇
  2017年   10712篇
  2016年   11646篇
  2015年   13392篇
  2014年   18442篇
  2013年   28131篇
  2012年   38542篇
  2011年   40955篇
  2010年   23623篇
  2009年   22719篇
  2008年   38660篇
  2007年   41401篇
  2006年   40814篇
  2005年   39932篇
  2004年   38422篇
  2003年   36736篇
  2002年   35621篇
  2001年   56666篇
  2000年   57675篇
  1999年   48652篇
  1998年   13725篇
  1997年   12527篇
  1996年   12910篇
  1995年   12189篇
  1994年   11280篇
  1993年   10548篇
  1992年   38621篇
  1991年   38050篇
  1990年   36815篇
  1989年   35617篇
  1988年   33041篇
  1987年   32337篇
  1986年   30865篇
  1985年   29122篇
  1984年   22224篇
  1983年   19405篇
  1982年   11521篇
  1979年   21205篇
  1978年   15569篇
  1977年   12952篇
  1976年   11976篇
  1975年   12946篇
  1974年   15763篇
  1973年   15513篇
  1972年   14653篇
  1971年   13667篇
  1970年   12912篇
  1969年   12211篇
  1968年   11349篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
T cell replete HLA-mismatched haploidentical transplantation (HIDT) with post-transplant cyclophosphamide is increasingly becoming an acceptable treatment approach for patients lacking timely access to a suitably matched related donor transplant (MRDT) or matched unrelated donor transplant (MUDT). Multiple recent registry and single-center studies have shown comparable overall survival (OS) and disease-free survival (DFS) rates among HIDT, MRDT, and MUDT with a significantly lower risk of acute and chronic graft-versus-host disease (GVHD) among HIDT recipients. Candidates for allogeneic hematopoietic stem cell transplantation (HSCT) often have access to multiple donor sources, and a relevant question is whether outcomes can be improved with a younger HLA-mismatched haploidentical donor (≤35 years) rather than an older matched related donor (≥35 years) or matched unrelated donor (≥35 years). We analyzed 406 consecutive allogenic HSCT recipients, with a median age of 54 years (range, 19 to 77), after a MRDT with a donor age of ≥35 years (n = 222), MUDT with a donor age of ≥35 years (n = 91), and HIDT with a donor age of ≤35 years (n = 93). Median follow-up time for survivors was 51.5 months. Compared with MRDT and MUDT, HIDT recipients had a similar median age at time of HSCT, hematopoietic cell transplant comorbidity index, disease risk index distribution, and donor recipient sex matching. The survival estimates and relapse incidence at 3 years post-HSCT were OS (64% for MRDT, 54% for MUDT, and 62% for HIDT), DFS (55% for MRDT, 44% for MUDT, and 58% for HIDT), Transplant related mortality (TRM) (19% for MRDT, 16% for MUDT, and 18% for HIDT), and relapse (26% for MRDT, 37% for MUDT, and 24% for HIDT). HIDT recipients had better 3-year relapse rates compared with MUDT recipients (24% versus 37%, P= .048), with similar DFS and OS in a univariate analysis. MRDT recipients had a better relapse rate (26% versus 37%, P = .042) compared with MUDT recipients. Recipients of HIDT also had significantly lower rates of moderate to severe chronic GVHD compared with MRDT and MUDT recipients (P = .01). Multivariable analysis showed no effect of donor on OS, DFS, relapse, and TRM. Recipients of HIDT from a young donor ≤35 years had similar OS, lower rates of chronic GVHD, and better chronic GVHD-free, relapse-free survival compared with patients undergoing transplantation with an MRD or a MUD donor ≥35 years. This study suggests that given a situation where a choice between a young haploidentical relative and an older matched unrelated donor is to be made, one can achieve similar survival with a haploidentical donor and significantly lower rates of chronic GVHD.  相似文献   
73.
74.
ObjectivesThe rise in carbapenem resistance among Gram-negative bacteria has renewed interest in colistin. Recently, the EUCAST-CLSI Polymyxin Breakpoints Working Group declared that broth microdilution (BMD) is the only valid method for colistin susceptibility testing. BMD is not easily incorporated into the routine work of clinical laboratories, and usually this test is incorporated serially, resulting in delayed susceptibility reporting. We tested a strategy of combining VITEK® 2 with a 2 μg/mL colistin agar dilution (VITEK® 2/AD) screening plate to improve performance and time to reporting of colistin susceptibility.MethodsColistin susceptibility for 364 clinical isolates was determined by VITEK® 2/AD and compared with the reference standard BMD according to the ISO 20776-1:2007 and CLSI guidelines. The EUCAST colistin susceptibility breakpoint of ≤2 μg/mL was used. Escherichia coli NCTC 13846 served as quality control strain. Agreement, very major error (VME) and major error rates were determined using ISO 20776-2:2007.ResultsThe VME rate for VITEK® 2 alone was 30.6% (15/49, 95% CI 18.3–45.4%), and was reduced to 10.2% (5/49, 95% CI 3.4–22.2%) using the VITEK® 2/AD combined testing. The combined testing had categorical agreement with BMD of 97% (354/364, 95% CI 95.0–98.7%), and a major error (ME) rate of 1.6% (5/315, 95% CI 0.5–3.7%). Using the combined testing, even against challenging strains, 349 (95.8%, 95% CI 93.3–97.7%) colistin susceptibility results could be reported, and only 15 isolates required further analysis by BMD.DiscussionOur method is simple to apply and allows rapid reporting of colistin susceptibility.  相似文献   
75.
Archives of Women's Mental Health - Latinas in the USA and Spanish-speaking countries experience elevated rates of perinatal depression (PND) because of high psychosocial stressors. Latinas are...  相似文献   
76.
Journal of Artificial Organs - A frequent complication of left ventricular assist devices (LVAD) is the LVAD-associated infections (LVADIs). Contamination may occur during initial surgery/admission...  相似文献   
77.
78.
We report a case of intestinal schistosomiasis in a patient who had not travelled outside Europe after migrating 20 years ago. Images of the Schistosoma mansoni eggs are shown that confirm the active nature of the infection.  相似文献   
79.
80.
ObjectivesHigh-quality diagnosis of bloodstream infections (BSI) is important for successful patient management. As knowledge on current practices of microbiological BSI diagnostics is limited, this project aimed to assess its current state in European microbiological laboratories.MethodsWe performed an online questionnaire-based cross-sectional survey comprising 34 questions on practices of microbiological BSI diagnostics. The ESCMID Study Group for Bloodstream Infections, Endocarditis and Sepsis (ESGBIES) was the primary platform to engage national coordinators who recruited laboratories within their countries.ResultsResponses were received from 209 laboratories in 25 European countries. Although 32.5% (68/209) of laboratories only used the classical processing of positive blood cultures (BC), two-thirds applied rapid technologies. Of laboratories that provided data, 42.2% (78/185) were able to start incubating BC in automated BC incubators around-the-clock, and only 13% (25/192) had established a 24-h service to start immediate processing of positive BC. Only 4.7% (9/190) of laboratories validated and transmitted the results of identification and antimicrobial susceptibility testing (AST) of BC pathogens to clinicians 24 h/day. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry from briefly incubated sub-cultures on solid media was the most commonly used approach to rapid pathogen identification from positive BC, and direct disc diffusion was the most common rapid AST method from positive BC.ConclusionsLaboratories have started to implement novel technologies for rapid identification and AST for positive BC. However, progress is severely compromised by limited operating hours such that current practice of BC diagnostics in Europe complies only partly with the requirements for optimal BSI management.  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