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   287412篇
  免费   21483篇
  国内免费   2717篇
耳鼻咽喉   3128篇
儿科学   7139篇
妇产科学   5131篇
基础医学   36231篇
口腔科学   5257篇
临床医学   29714篇
内科学   58518篇
皮肤病学   3935篇
神经病学   26243篇
特种医学   9421篇
外国民族医学   13篇
外科学   41698篇
综合类   9174篇
现状与发展   17篇
一般理论   340篇
预防医学   25000篇
眼科学   7522篇
药学   21001篇
  62篇
中国医学   2820篇
肿瘤学   19248篇
  2023年   1854篇
  2022年   3812篇
  2021年   7244篇
  2020年   4746篇
  2019年   6475篇
  2018年   7253篇
  2017年   5778篇
  2016年   6121篇
  2015年   7405篇
  2014年   10473篇
  2013年   13827篇
  2012年   21035篇
  2011年   21990篇
  2010年   12839篇
  2009年   11364篇
  2008年   18974篇
  2007年   19634篇
  2006年   19231篇
  2005年   19040篇
  2004年   17455篇
  2003年   16220篇
  2002年   15028篇
  2001年   2485篇
  2000年   1933篇
  1999年   2542篇
  1998年   3307篇
  1997年   2740篇
  1996年   2317篇
  1995年   2207篇
  1994年   1862篇
  1993年   1653篇
  1992年   1352篇
  1991年   1244篇
  1990年   1073篇
  1989年   1027篇
  1988年   1016篇
  1987年   992篇
  1986年   1011篇
  1985年   1009篇
  1984年   1273篇
  1983年   1180篇
  1982年   1424篇
  1981年   1354篇
  1980年   1180篇
  1979年   724篇
  1978年   779篇
  1977年   666篇
  1976年   593篇
  1975年   482篇
  1974年   490篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Prezant  David J. 《Lung》2007,186(1):94-102

To date, the main respiratory health consequence from the collapse of the World Trade Center (WTC) on September 11, 2001 has been the “WTC Cough Syndrome” (chronic rhinosinusitis, asthma, and/or bronchitis, often complicated by gastroesophageal reflux dysfunction). Syndrome incidence and severity have been linked to WTC dust exposure intensity. While it is too early to ascertain long-term effects of WTC dust exposure, effective treatment guidelines have been designed through a collaborative effort by the three established centers of excellence for WTC medical monitoring and treatment and the WTC Registry. These treatment recommendations are described here.

  相似文献   
92.
目的建立滑膜炎颗粒剂中原儿茶醛的含量测定方法质量。方法采用高效液相色谱法对方中原儿茶醛进行含量测定。结果高效液相色谱法测定结果表明原儿茶醛在0.1005~1.005μg范围内呈线性关系,平均加样回收率为99.22%;RSD为0.72%。结论本法简便,重现性好、结果可靠,可作为控制滑膜炎颗粒剂的质量方法。  相似文献   
93.
132例男性不育患者遗传学病因分析   总被引:3,自引:0,他引:3  
目的:对男性不育患者进行遗传学病因分析,并探讨其遗传效应。方法:采取132例男性不育患者外周血进行染色体核型分析。结果:132例男性不育患者中,染色体异常24例,染色体变异22例。其中大Y20例,47,XXY18例,45.XY,t(13;14)3例,小Y和46,XY,inv(9)各2例,46,XY,t(9;22)1例。结论:染色体异常是男性不育的重要原因,并建议男性不育患者进行基因诊断,以便确诊是否属于遗传病,为生育提供指导,避免盲目治疗。  相似文献   
94.
Building small things for small patients is tough, and sometimesexpensive, but it really needs to be done. I was pleased tosee the paper by Thierry Scohy et al., the Rotterdam PediatricCardiology, Anesthesiology and Surgery group, in a paper publishedin this issue of the European Journal of Echocardiography, asuitable venue for this report, since so much of the developmentof this device has been European. In this paper, the group reportstheir experience using a micromultiplane transesophageal probe  相似文献   
95.
96.
Oral health was examined in a random sample of 1377 people in three 70-year-old cohorts studied within 5-yr intervals. During the studied period 1971-1983 the prevalence of toothlessness decreased from 52 to 34%. Toothlessness in men was more common in smokers, 48%, and ex-smokers, 32%, than in non-smokers, 20%. Eichner's index was used as a measurement of dental invalidity. This index showed a worse dental state among smokers and ex-smokers compared to non-smokers. Multivariate analyses indicated that tobacco smoking was a major independent risk factor for tooth loss in elderly men.  相似文献   
97.
98.
99.
We cared for a patient with methicillin-resistant Staphylococcus aureus bacteremia who experienced clinical failure with daptomycin. The failure was accompanied by progressive elevation of the daptomycin minimum inhibitory concentration during treatment. DNA fingerprinting confirmed that the minimum inhibitory concentration elevation occurred within the same strain of methicillin-resistant Staphylococcus aureus. This observation provides important new information to clinicians who adopt this promising drug for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus.  相似文献   
100.
Recently, a resin-based calcium phosphate cement (RCPC) has been reported as a remineralizing pulp-capping or lining cement. RCPC consists mainly of tetracalcium and dicalcium phosphates, ethoxylated bisphenol A dimethacrylate and pyromellitic glycerol dimethacrylate monomers and photo- and chemical initiators. OBJECTIVES: Here, the cytotoxic effects of RCPC were evaluated. The hypothesis was that RCPC induced only minor cytotoxic response in immortalized murine odontoblast and pulp cells, comparable to that produced by similar dimethacrylates due to unpolymerized dimethacrylate monomer present after curing. METHODS: Cytotoxicity was determined following the changes in cell succinate dehydrogenase activity after 24 h exposure to the cement components and after a 24 h recovery period. A fourfold range of concentrations was tested of the monomers, the eluate of cured RCPC leached in Dulbecco's modified Eagle's medium, and crushed cured cement in dimethyl sulfoxide. RESULTS: The monomers themselves had cytotoxicities similar to those reported for other dimethacrylates, although they are significantly less toxic than Bis-GMA. Differential cell sensitivity was demonstrated, with the pulp cells having greater sensitivity to the unpolymerized monomer than the odontoblast-like cells. The leached components have cytotoxicity similar to that of the free monomers. The crushed material demonstrated no apparent cytotoxicity at the dilutions tested. SIGNIFICANCE: These data demonstrate that RCPC has an in vitro cytotoxicity that is comparable to other materials containing dimethacrylate monomers and suggest that the material may be suitable for use in dental restorations. The data also indicate that the pulp cells appear more sensitive to dimethacrylates than the odontoblasts.  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