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   19584篇
  免费   1408篇
  国内免费   362篇
耳鼻咽喉   106篇
儿科学   597篇
妇产科学   326篇
基础医学   1585篇
口腔科学   559篇
临床医学   1770篇
内科学   2795篇
皮肤病学   190篇
神经病学   1657篇
特种医学   1471篇
外科学   2015篇
综合类   1463篇
现状与发展   1篇
一般理论   2篇
预防医学   3522篇
眼科学   229篇
药学   1449篇
  3篇
中国医学   259篇
肿瘤学   1355篇
  2024年   24篇
  2023年   309篇
  2022年   369篇
  2021年   594篇
  2020年   736篇
  2019年   714篇
  2018年   658篇
  2017年   649篇
  2016年   676篇
  2015年   593篇
  2014年   1232篇
  2013年   1403篇
  2012年   1078篇
  2011年   1210篇
  2010年   884篇
  2009年   932篇
  2008年   911篇
  2007年   983篇
  2006年   863篇
  2005年   835篇
  2004年   753篇
  2003年   701篇
  2002年   543篇
  2001年   427篇
  2000年   341篇
  1999年   309篇
  1998年   255篇
  1997年   197篇
  1996年   153篇
  1995年   218篇
  1994年   208篇
  1993年   175篇
  1992年   205篇
  1991年   165篇
  1990年   109篇
  1989年   107篇
  1988年   117篇
  1987年   85篇
  1986年   77篇
  1985年   115篇
  1984年   73篇
  1983年   56篇
  1982年   68篇
  1981年   52篇
  1980年   44篇
  1979年   25篇
  1978年   39篇
  1977年   32篇
  1976年   15篇
  1975年   11篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
ObjectivesChagas disease (CD) treatment is limited to two therapeutic options: benznidazole (generally the first option in Spain) and nifurtimox. Both drugs present high rates of adverse reactions and treatment discontinuation and there is no consensus regarding the most effective administration schedule for benznidazole or how to prevent and manage treatment toxicity. We aim to compare the tolerability and treatment discontinuation rate between two different treatment schemes with benznidazole.MethodsThis was a prospective observational study of adult patients with CD, enrolled from January 2014 to March 2018 in two referral centres in Madrid (Spain). Participants were treated either with benznidazole 5 mg/kg/day (full dose) over 60 days (benznidazole standard dose scheme (BSD)), or with an escalating dose lasting 5 days up to a maximum of 300 mg/day (benznidazole increasing dose scheme (BID)).Results471 patients were analysed: 201 in the BSD group and 270 in the BID group. There were no significant differences regarding age (40.4 (SD 8.7) vs 41 (SD 8.2) years), sex (74.1% (149/201) vs 68.5% (185/270) women), weight (69.4 (SD 12.8) vs 68.9 (SD 11) kg) or nationality (97.5% (196/201) vs 96.7% (261/270) Bolivians) between groups. There were also no differences in adverse reactions rate (55.2% (111/201) vs 55.6% (150/270)), number of adverse reactions per patient, adverse reactions type (except for arthralgias and myalgias which occurred more frequently in the BID group (0% (0/111) BSD vs 8% (12/150) BID; p 0.002)) and degree and time to first adverse reactions. There was significantly more treatment discontinuation (49.8% (100/201) vs 33.0% (89/270); p <0.001) in the BSD group, but not during the first 30 days of treatment (32.3% (65/201) vs 25.6% (69/270); p 0.08).ConclusionThe use of increasing doses of benznidazole for 5 days and a maximum dose of 300 mg, does not significantly improve drug tolerability. However, while the treatment discontinuation rates were similar during the first 30 days of treatment, it may improve the treatment completion rate at 60 days.  相似文献   
62.
The neural crest serves as a powerful and tractable model paradigm for understanding collective cell migration. The neural crest cell populations are well-known for their long-distance collective migration and contribution to diverse cell lineages during vertebrate development. If neural crest cells fail to reach a target or populate an incorrect location, then improper cell differentiation or uncontrolled cell proliferation can result. A wide range of interdisciplinary studies has been carried out to understand the response of neural crest cells to different stimuli and their ability to migrate to distant targets. In this critical commentary, we illustrate how an interdisciplinary collaboration involving experimental and mathematical modeling has led to a deeper understanding of cranial neural crest cell migration. We identify open questions and propose possible ways to start answering some of the challenges arising.  相似文献   
63.
64.
65.
66.
67.
Hit, Lead & Candidate Discovery
A variety of novel 2-(methyl/phenyl)-3-(4-(5-substituted-1,3,4-oxadiazol-2-yl)phenyl) quinazolin-4(3H)-ones have been synthesized by treating 3-(4-(5-mercapto-1,3,4-oxadiazol-2-yl)phenyl)-2-(methyl/phenyl)-quinazolin-4(3H)-one with a variety of secondary amines. Graph theoretical analysis was used in identification of drug target that is, NMDAR (N-methyl-d -aspartate receptors). The observed reports of in silico modeling and ligand based toxicity, metabolism prediction studies were encouraging us to synthesize of title compounds and evaluate their antiepileptic effects. The title compounds were tested for its antiepileptic potency by MES and scPTZ model. Rotorod test is used to assess its neurotoxicity. In the preliminary test it was found that in MES test, analogs 6d , 6e , 6f, and 6l were potent; whereas in scPTZ test analogs 6d , 6e , 6f, and 6k displayed potent antiepileptic activity. Additionally these five derivatives were tested in rats orally at a dose of 30 mg/kg and found that compounds 2-methyl-3-(4-(5-morpholino-1,3,4-oxadiazol-2-yl)phenyl)quinazolin-4(3H)-one 6e and 2-methyl-3-(4-(5-(piperidin-1-yl)-1,3,4-oxadiazol-2-yl)phenyl)quinazolin-4(3H)-one 6f exhibited superior activity than reference Phenytoin. In MES test, these derivatives 6e and 6f showed activity at 30 mg/kg i.p. dose after 0.5 hr and 4.0 hr. In scPTZ test these derivatives 6e and 6f showed activity at 100 and 300 mg/kg i.p. dose after 0.5 hr and 4.0 hr, respectively.  相似文献   
68.
69.
《Surgery (Oxford)》2020,38(6):297-302
The maintenance of anorectal continence and defaecation is complex. The disruption of these mechanisms can result in symptoms of either faecal incontinence or obstructive defaecation. Both conditions can have significant impact on quality of life. This article details the clinical assessment of presenting patients to establish potential causes, grade the severity of the symptoms and to assess the impact on their quality of life. The appropriate specialized radiological and physiological investigations aim to evaluate the structural integrity and function of the anal sphincter, the anorectal and pelvic floor musculature and measure the transitory function of the colon.  相似文献   
70.
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