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   22416篇
  免费   2475篇
  国内免费   586篇
耳鼻咽喉   424篇
儿科学   440篇
妇产科学   288篇
基础医学   2174篇
口腔科学   362篇
临床医学   5554篇
内科学   2078篇
皮肤病学   89篇
神经病学   1686篇
特种医学   1417篇
外科学   2148篇
综合类   3650篇
现状与发展   1篇
一般理论   3篇
预防医学   2503篇
眼科学   236篇
药学   1013篇
  256篇
中国医学   860篇
肿瘤学   295篇
  2024年   95篇
  2023年   556篇
  2022年   916篇
  2021年   1382篇
  2020年   1424篇
  2019年   1037篇
  2018年   979篇
  2017年   1098篇
  2016年   951篇
  2015年   904篇
  2014年   1896篇
  2013年   2141篇
  2012年   1455篇
  2011年   1391篇
  2010年   1174篇
  2009年   1059篇
  2008年   987篇
  2007年   903篇
  2006年   732篇
  2005年   618篇
  2004年   556篇
  2003年   482篇
  2002年   367篇
  2001年   288篇
  2000年   243篇
  1999年   177篇
  1998年   169篇
  1997年   148篇
  1996年   159篇
  1995年   130篇
  1994年   104篇
  1993年   105篇
  1992年   119篇
  1991年   74篇
  1990年   68篇
  1989年   58篇
  1988年   56篇
  1987年   61篇
  1986年   45篇
  1985年   49篇
  1984年   65篇
  1983年   34篇
  1982年   38篇
  1981年   30篇
  1980年   31篇
  1979年   21篇
  1978年   20篇
  1977年   20篇
  1976年   14篇
  1975年   14篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
对医学工程技术人员岗位培训方式的探讨   总被引:1,自引:0,他引:1  
本文对如何开展医学工程技术人员的培训进行了分析,并提出了一些具体的办法。  相似文献   
82.
Objectives  To explore the effect of obstetric emergency training on knowledge. Furthermore, to assess if acquisition of knowledge is influenced by the training setting or teamwork training.
Design  A prospective randomised controlled trial.
Setting  Training was completed in six hospitals in the South West of England, UK and at the Bristol Medical Simulation Centre, UK.
Population  Midwives and obstetric doctors working for the participating hospitals were eligible for inclusion in the study. A total of 140 participants (22 junior and 23 senior doctors, 47 junior and 48 senior midwives) were studied.
Methods  Participants were randomised to one of four obstetric emergency training interventions: (1) 1-day course at local hospital, (2) 1-day course at simulation centre, (3) 2-day course with teamwork training at local hospital and (4) 2-day course with teamwork training at simulation centre.
Main outcome measures  Change in knowledge was assessed by a 185 question Multiple-Choice Questionnaire (MCQ) completed up to 3 weeks before and 3 weeks after the training intervention.
Results  There was a significant increase in knowledge following training; mean MCQ score increased by 20.6 points (95% CI 18.1–23.1, P < 0.001). Overall, 123/133 (92.5%) participants increased their MCQ score. There was no significant effect on the MCQ score of either the location of training (two-way analysis of variants P = 0.785) or the inclusion of teamwork training ( P = 0.965).
Conclusions  Practical, multiprofessional, obstetric emergency training increased midwives' and doctors' knowledge of obstetric emergency management. Furthermore, neither the location of training, in a simulation centre or in local hospitals, nor the inclusion of teamwork training made any significant difference to the acquisition of knowledge in obstetric emergencies.  相似文献   
83.
The present paper outlines the development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities. Although based on our experience in South Australia with the University Placement Allocation Committee (UPAC), the primary goal is to outline the steps that would be useful if placement coordinators at other universities in Australia decided to establish and maintain an allocation committee. A survey of field supervisors was also conducted and field supervisors endorsed UPAC as a constructive mechanism for allocating community placements.  相似文献   
84.
85.
The cardiorespiratory effects of intermittent positive pressure ventilation and high frequency jet ventilation with and without positive end expiratory pressure were compared in patients following valvular heart surgery (mitral and/or aortic). Twenty patients received intermittent positive pressure ventilation and high frequency jet ventilation with 0, 0.5 and 1.0 kPa positive end expiratory pressure. High frequency jet ventilation was well tolerated. The addition of 1.0 kPa positive end expiratory pressure was associated with preservation of the arterial oxygen tension without any increase in shunt or significant adverse haemodynamic effect. The results are discussed and compared with a previous study of high frequency jet ventilation following aortocoronary bypass graft surgery.  相似文献   
86.
无创正压通气不同压力支持水平对正常人呼吸做功的影响   总被引:2,自引:0,他引:2  
目的 :观察无创正压通气 (NIPPV)不同压力水平对正常人呼吸做功的影响 ,为临床合理地应用NIPPV提供理论依据。方法 :选择 9例正常人行NIPPV并寻找出“最舒适”的吸气压力水平 (IPAP) ,在此压力基础上增加或减少 2 5 %的压力 ,构成低IPAP、最舒适IPAP和高IPAP三个压力水平 ,每一IPAP水平通气 15min以上 ,比较不同压力水平呼吸做功改变。结果 :受试者认为“最舒适”的IPAP为 (11.33± 3.2 0 )cmH2 O ,EPAP为 (4 .5 6± 0 .88)cmH2 O[相当于PSV水平为 (6 .77± 3.2 0 )cmH2 O]。与自主呼吸相比 ,NIPPV增加VE的同时 ,总的呼吸做功(Wtot)明显增加 (P <0 .0 5 ) ,而受试者吸气肌做功占总的吸气做功的百分比 (Wi,p/Wi)明显减少 (P <0 .0 5 )。在最舒适IPAP时 ,Wi,p/Wi降低到基础值的 14 %± 9%。这种变化趋势与IPAP的水平相关。结论 :NIPPV可以显著降低吸气肌肉做功。吸气肌做功减少的比例与IPAP的水平相关。研究的结果为NIPPV时PSV的参数设定提供了生理学的依据。  相似文献   
87.
The present study completed a previous randomized trial that demonstrated the protective effect of 1-year psoas training on lumbar bone loss in postmenopausal women. Computerized tomography had been carried out at the beginning (CT1) and at the end (CT2) of this trial. In the present study, 67 women having completed the first trial were asked to practice psoas exercises (60 hip flexions in sitting position with a 5 kg weight on the knee) for 2 additional years with a third CT control at the end of this period (CT3). The aim of this complementary study was to assess the compliance rate and long-term effect on bone of daily psoas muscle training over a longer period. Twenty-one women performed this daily psoas training for 3 years from CT1 to CT3, and 14 acted as controls during the same period. Fourteen women were controls during the first year (from CT1 to CT2) but practiced psoas training during the following 2 years (from CT2 to CT3). Four women were psoas trained during the first year (from CT1 to CT2) and subsequently crossed over to the control group for the last 2 years. The compliance rate was 42%, with an attendance rate of 88%. The lumbar bone loss was lower in the 21 women trained over the 3 years (−3.26 ± 28.45 mg/cm3) than in the 14 untrained women (−16.79 ± 8.51 mg/cm3) (P= 0.02). The bone loss was not significantly reduced between the two periods of the study in the 12 women having been controls from CT1 to CT2 and having crossed over to the active training group from CT2 to CT3. Psoas training may be effective against lumbar bone loss. We conclude that specific training may play a contributing role in the preventive strategy to avoid osteoporosis. Received: 23 February 1996 / Accepted: 25 October 1996  相似文献   
88.
运动训练对雄性大鼠垂体─性腺轴功能的影响   总被引:3,自引:2,他引:1  
本研究通过使用自己制造的大鼠流动水游泳池,对雄性大鼠进行了6周递增负荷的游泳训练,以此来探讨运动训练对大鼠垂体-性腺轴功能的影响,结果显示:与安静对照大鼠相比,训练大鼠的一般状态较差,血清睾酮水平显著降低(P<0.05),血清睾酮/皮质酮比值平均降低了30%以上;而血清LH和FSH水平未见明显变化。通过对大鼠睾丸组织LH/CG受体的测定,显示运动训练虽未引起其最大结合量的改变,却能使其解离常数显著升高(P<0.05)。提示此种训练可能通过降低睾丸LH/CG受体对垂体分泌LH的亲和力,从而影响睾酮的合成。  相似文献   
89.
Summary. Divers have worked at 500 m depth in the sea and have reached 700 m in simulated chamber dives. A prerequisite for this has been extensive physiological studies of the body's reactions to pressure and pressure changes. This paper reviews such physiological and pathophysiological studies with emphasis on recent developments.  相似文献   
90.
应用物理学,化学和工艺等方法,分别处理5种国内外敏感器,以组成相应呼吸敏感电极,结果显示,各种电极的气-电转换性能有明显改善,其中以上海复旦片性能达到弱呼吸敏感电极要求。  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