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   1188篇
  免费   122篇
  国内免费   9篇
耳鼻咽喉   21篇
儿科学   38篇
妇产科学   13篇
基础医学   133篇
口腔科学   20篇
临床医学   118篇
内科学   213篇
皮肤病学   8篇
神经病学   126篇
特种医学   94篇
外国民族医学   3篇
外科学   182篇
综合类   24篇
预防医学   129篇
眼科学   34篇
药学   96篇
中国医学   2篇
肿瘤学   65篇
  2022年   14篇
  2021年   37篇
  2020年   14篇
  2019年   26篇
  2018年   41篇
  2017年   33篇
  2016年   22篇
  2015年   33篇
  2014年   27篇
  2013年   42篇
  2012年   45篇
  2011年   73篇
  2010年   35篇
  2009年   39篇
  2008年   44篇
  2007年   63篇
  2006年   50篇
  2005年   42篇
  2004年   29篇
  2003年   39篇
  2002年   29篇
  2001年   23篇
  2000年   24篇
  1999年   26篇
  1998年   29篇
  1997年   24篇
  1996年   15篇
  1995年   16篇
  1994年   18篇
  1993年   14篇
  1992年   18篇
  1991年   13篇
  1990年   24篇
  1989年   22篇
  1988年   19篇
  1987年   15篇
  1986年   17篇
  1985年   18篇
  1984年   13篇
  1983年   9篇
  1982年   10篇
  1980年   12篇
  1976年   11篇
  1974年   7篇
  1973年   16篇
  1971年   18篇
  1969年   8篇
  1968年   9篇
  1967年   11篇
  1966年   8篇
排序方式: 共有1319条查询结果,搜索用时 0 毫秒
81.
82.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.  相似文献   
83.
84.
目的:评价ThromCat血栓切除导管系统(ThromCat Thrombectomy Catheter System,TTC)在急性冠状动脉综合征(ACS)介入治疗应用中的安全性、工作性能及有效性.方法:入选14例ACS患者进行经皮冠状动脉介入治疗(PCI),分析TTC操作的成功率、TTC应用的临床成功率、术中并发症和术后随访30 d心脏不良事件.结果:TTC操作成功11例,TTC临床成功10例,PCI成功13例,并不伴有心脏不良事件.在PCI中,心肌梗死溶栓治疗(TIMI)血流由使用TIC前的0.5(2.0)升高至使用后的2.0(1.0),心肌灌注分级(MBG)由使用前的1.0(2.0)升高至使用后的2.0(1.0),差异均有统计学意义(均P<0.01).结论:在ACS患者中行PCI,TTC能安全有效地去除非严重钙化的冠状动脉内的血栓.并发症少,操作简单易行,减少PCI手术引起的并发症.  相似文献   
85.
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
86.
87.
The increase in psychoneurotic admissions to mental health facilities in the nation as well as the preponderance of such cases in existing community oriented facilities prompted the examination of the socioeconomic characteristics of such patients admitted to the mental health facilities in Ohio.Results showed higher admission rates for: (a) metropolitan residents than nonmetropolitan residents; (b) females than males; (c) whites than nonwhites; (d) females not employed than those of all occupational categories except laborers; (e) laborers followed by managerial and professional workers than any other occupational category; (f) married females than single females, the highest rates, for both sexes, occurring for the divorced and separated. Implications of these findings as they relate to the present community mental health approach are discussed.  相似文献   
88.
89.
90.
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