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   1683186篇
  免费   126475篇
  国内免费   3753篇
耳鼻咽喉   21716篇
儿科学   55505篇
妇产科学   46149篇
基础医学   239630篇
口腔科学   48702篇
临床医学   150280篇
内科学   330759篇
皮肤病学   38637篇
神经病学   130305篇
特种医学   63831篇
外国民族医学   242篇
外科学   256583篇
综合类   38822篇
现状与发展   4篇
一般理论   531篇
预防医学   123401篇
眼科学   40011篇
药学   123230篇
  7篇
中国医学   4345篇
肿瘤学   100724篇
  2019年   13529篇
  2018年   19963篇
  2017年   15223篇
  2016年   16616篇
  2015年   18967篇
  2014年   26222篇
  2013年   37956篇
  2012年   52755篇
  2011年   55441篇
  2010年   32778篇
  2009年   30704篇
  2008年   51536篇
  2007年   54816篇
  2006年   55276篇
  2005年   52562篇
  2004年   50732篇
  2003年   48051篇
  2002年   46257篇
  2001年   91699篇
  2000年   93445篇
  1999年   76606篇
  1998年   18777篇
  1997年   16275篇
  1996年   16425篇
  1995年   16638篇
  1994年   15231篇
  1993年   14006篇
  1992年   57319篇
  1991年   55265篇
  1990年   52963篇
  1989年   50736篇
  1988年   46120篇
  1987年   44925篇
  1986年   42202篇
  1985年   39987篇
  1984年   29318篇
  1983年   24849篇
  1982年   13844篇
  1981年   12330篇
  1979年   25480篇
  1978年   17538篇
  1977年   14862篇
  1976年   13833篇
  1975年   14529篇
  1974年   17612篇
  1973年   16919篇
  1972年   15679篇
  1971年   14442篇
  1970年   13419篇
  1969年   12511篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
Major depressive disorder (MDD) is a disabling and highly prevalent mood disorder as well as a common cause of suicide. Chronic stress, inflammation, and intestinal dysbiosis have all been shown to play crucial roles in the pathophysiology of MDD. Although conventional antidepressants are widely used in the clinic, they can take weeks to months to produce therapeutic effects. The discovery that ketamine promotes fast and sustaining antidepressant responses is one of the most important breakthroughs in the pharmacotherapy of MDD. However, the adverse psychomimetic/dissociative and neurotoxic effects of ketamine discourage its chronic use. Therefore, agmatine, an endogenous glutamatergic modulator, has been postulated to elicit fast behavioral and synaptogenic effects by stimulating the mechanistic target of rapamycin complex 1 signaling pathway, similar to ketamine. However, recent evidence has demonstrated that the modulation of the NLR family pyrin domain containing 3 inflammasome and gut microbiota, which have been shown to play a crucial role in the pathophysiology of MDD, may also participate in the antidepressant-like effects of both ketamine and agmatine. This review seeks to provide evidence about the mechanisms that may underlie the fast antidepressant-like responses of agmatine in preclinical studies. Considering the anti-inflammatory properties of agmatine, it may also be further investigated as a useful compound for the management of MDD associated with a pro-inflammatory state. Moreover, the fast antidepressant-like response of agmatine noted in animal models should be investigated in clinical studies.  相似文献   
43.
44.
45.
46.
47.
48.
IntroductionThe current paradigm of the management of rheumatoid arthritis (RA) recommends achieving a state of remission or low disease activity through the treat-to-target strategy. Our study assesses adherence to this strategy.MethodPatients with RA (ACR-EULAR 2010 criteria) were included. From each centre, 19 patients were randomly selected. Clinical histories (CH) were assessed by independent auditors, checking compliance with predefined quality criteria. The study was approved by ethics committees.ResultsWe included 856 patients (mean age 54 years; 71% women). The use of a combined index (CI) was recorded in 61% of cases. Visits were recorded every 4 weeks using a CI in 4% of CH while attempts were made to achieve remission. Monitoring of disease activity every 6–8 months after reaching the target was recorded in 73% of cases.ConclusionsThe implementation of the treat-to-target strategy is barely recorded in patients with RA in routine clinical practice.  相似文献   
49.
IntroductionThe usage of extended-criteria donors (ECD) became a routinely accepted manner in the last decade. ECD is a potential risk factor for antibody-mediated rejection. Analysis of lymphocyte subsets might be a complementary diagnostic toolkit because there is limited knowledge about this term.MethodBetween May 12, 2016, and September 4, 2019, a total of 130 patients who had undergone kidney transplant were investigated. Patients were divided in ECD and standard criteria donor (SCD) groups. Blood samples were collected before the operation, then in the first week and after 30, 60, 180, and 365 days. Besides routine laboratory tests, multicolor flow cytometry was performed for lymphocyte subsets.ResultsECD grafts were transplanted to older recipients. The number of CD4+ cells increased in the SCDs from the first week to until the end of first month, and then decreased. The number of CD4+ cells decreased from the beginning of the study until the end of first year to 66% of its original value in ECDs. At the first month, the number of CD19+ cells was higher in SCD compared with ECD cases; the number then decreased in both groups. T-regulatory cells had a drop at the first week that lasted until the first month. A bigger increase in SCD and a moderate increase in ECD group were then observed. The kinetics of CD19+ and CD19+ naive cells are similar in the ECD and SCD groups. In the SCD group, cell count decreased in both CD19+ (13%) and CD19+ naive (12%) between third and sixth month. The count of CD19+ cells decreased by 9%, but the count of CD19+ naive cells increased by 11% between the sixth month and first year.DiscussionThe prolonged postoperative uremic state caused by the poorer initial function, together with an aging immune system, explains the weaker immune response in ECD patients, which may be the cause of the decreased number of memory and regulatory T cells. Older patients with an ECD graft need a tailored, personalized, and less aggressive immunosuppressive treatment.  相似文献   
50.
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