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   98806篇
  免费   9869篇
  国内免费   946篇
耳鼻咽喉   339篇
儿科学   2073篇
妇产科学   2155篇
基础医学   6160篇
口腔科学   4752篇
临床医学   17754篇
内科学   8120篇
皮肤病学   674篇
神经病学   5188篇
特种医学   1345篇
外科学   4000篇
综合类   10652篇
现状与发展   3篇
一般理论   95篇
预防医学   36115篇
眼科学   447篇
药学   4855篇
  136篇
中国医学   2590篇
肿瘤学   2168篇
  2024年   359篇
  2023年   2875篇
  2022年   3933篇
  2021年   5484篇
  2020年   5497篇
  2019年   5145篇
  2018年   4559篇
  2017年   4391篇
  2016年   4271篇
  2015年   4148篇
  2014年   6697篇
  2013年   8899篇
  2012年   5930篇
  2011年   6346篇
  2010年   4695篇
  2009年   4731篇
  2008年   4661篇
  2007年   4606篇
  2006年   3979篇
  2005年   3057篇
  2004年   2614篇
  2003年   2242篇
  2002年   1659篇
  2001年   1583篇
  2000年   1369篇
  1999年   952篇
  1998年   789篇
  1997年   636篇
  1996年   546篇
  1995年   381篇
  1994年   350篇
  1993年   340篇
  1992年   289篇
  1991年   236篇
  1990年   196篇
  1989年   154篇
  1988年   185篇
  1987年   125篇
  1986年   107篇
  1985年   112篇
  1984年   79篇
  1983年   56篇
  1982年   52篇
  1981年   43篇
  1980年   53篇
  1979年   33篇
  1978年   37篇
  1977年   37篇
  1976年   33篇
  1975年   34篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
中国新疆与哈萨克斯坦共和国生态环境特点极为相似,荒漠、半荒漠草地类型占草原面积的首位。由草原研究所派出的科技交流团,先后考察了哈国荒漠草地现状与改良利用情况,就优良旱生牧草新品种选育和荒漠、半荒漠区无灌溉条件下人工草地建植与管理技术模式达成技术合作事宜。  相似文献   
172.
目的了解广东高校贫困生心理健康状况并提出相应建议。方法用康奈尔医学指数(CMI)及社会支持评定量表,对广东省5所高校500名学生进行了问卷调查,并采用SPSS11.0进行相关统计和分析。结果贫困大学生的心理健康状况在某些方面存在不足,在性别、地域来源等有差异。结论高校应重视贫困大学生的心理健康状况,加强情感引导,尤其不能忽视对女贫困大学生的关注和帮助。  相似文献   
173.
To reduce racial and ethnic disparities in health care, managers, policy makers, and researchers need valid and reliable data on the race and ethnicity of individuals and populations. The federal government is one of the most important sources of such data. In this paper we review the strengths and weaknesses of federal data that pertain to racial and ethnic disparities in health care. We describe recent developments that are likely to influence how these data can be used in the future and discuss how local programs could make use of these data.  相似文献   
174.
对鲜山药中水溶性粗多糖的提取工艺进行了研究,通过单因素试验和L9(34)正交试验,研究了料液比、提取温度、时间和乙醇体积分数对粗多糖得率的影响,极差分析及方差分析结果表明提取温度和料液比是影响山药粗多糖提取的主要因素,较优的工艺为料液比1 g:9 mL,温度50 ℃,时间2.5 h,乙醇体积分数75%,在此工艺条件下,鲜山药粗多糖得率为0.2449%(以鲜山药质量计).  相似文献   
175.
完美主义与基督教信仰   总被引:2,自引:0,他引:2  
目的 考察个体的宗教信仰与完美主义心理之间的关系。方法 采用质的研究方法,对两位受访者(分别为功能障碍型完美主义与健康的完美主义)追行个案研究。结果 两名受访者的基督教(新教)信仰封其完关主义的负面倾向有所矫正,受访者的人际关系和自我认知因为宗教信仰而有所改善。结论 基督教(新教)信仰有利于修正受访者自体表象与权威客体表象的关系。在象征意义上,“上帝”的概念可以理解为“较好的”权威客体表象。  相似文献   
176.
Since the International Conference on Population and Development held in Cairo in 1994, and the Fourth World Conference on Women held in Beijing in 1995, the international organizations and public health communities have paid more attention to reproductiv…  相似文献   
177.
BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up.  相似文献   
178.
The world is experiencing a rapid development in the 21th century. All countries estab- lished their schemes considering their situation of social and economic development. It is widely recognized that the key element of development is “people”. As to t…  相似文献   
179.
Objective: To investigate on the feasibility, safety, and effectiveness of a new bioabsorbable material for lung staple-line reinforcement. Methods: This prospective open trial included 66 patients (mean age of 56 ± 17 years) who underwent various types of lung resection using staplers with knitted calcium alginate sleeves for buttressing (FOREseal™, Laboratoires Brothier, Nanterre, France) at three academic centers: 29 lobectomies, 22 emphysema surgeries, 15 wedge resections or lung biopsies. Intraoperative air leakage was assessed at a mean respiratory peak pressure of 30 cmH2O, and rated as grade 1, 2, or 3. Persistent air leakage in the postoperative course, as well as any relevant event, was assessed daily. The follow-up period was of 6 months. Results: No technical problem linked to the device occurred. Hemostasis of the cutting edges was completed in all patients. Fifty-six percent of the patients had no intraoperative air leak and 27.3% had grade 1 leaks. Mean postoperative air leaks and thoracic drainage times were 1.9 ± 2.3 days and 6 ± 5.3 days, respectively. In-hospital mortality was nil. There was no empyema. Mean hospital stay was 9.1 ± 6.6 days. At follow-up, one patient underwent lung transplantation, and pathology of the explanted specimen showed the absence of device-related foreign-body inflammation. One patient complained from metalloptysis, and another one, with a metastatic invasive aspergillosis, developed an infectious recurrence that required reoperation. Conclusions: FOREseal is an ergonomic, safe, and promising new material instead of nonabsorbable materials and xenomaterials for staple-line reinforcement. A randomized comparative study is now in progress.  相似文献   
180.
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