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   26432篇
  免费   578篇
  国内免费   47篇
耳鼻咽喉   768篇
儿科学   632篇
妇产科学   2190篇
基础医学   3770篇
口腔科学   1009篇
临床医学   981篇
内科学   4571篇
皮肤病学   834篇
神经病学   2360篇
特种医学   352篇
外科学   2463篇
综合类   94篇
一般理论   1篇
预防医学   1895篇
眼科学   1138篇
药学   3167篇
中国医学   41篇
肿瘤学   791篇
  2022年   300篇
  2021年   654篇
  2020年   226篇
  2019年   351篇
  2018年   509篇
  2017年   361篇
  2016年   389篇
  2015年   440篇
  2014年   637篇
  2013年   867篇
  2012年   1116篇
  2011年   1264篇
  2010年   642篇
  2009年   388篇
  2008年   784篇
  2007年   1039篇
  2006年   1112篇
  2005年   1036篇
  2004年   1059篇
  2003年   1033篇
  2002年   871篇
  2001年   698篇
  2000年   685篇
  1999年   571篇
  1998年   169篇
  1992年   376篇
  1991年   320篇
  1990年   349篇
  1989年   402篇
  1988年   458篇
  1987年   444篇
  1986年   448篇
  1985年   422篇
  1984年   343篇
  1983年   254篇
  1979年   521篇
  1978年   314篇
  1977年   255篇
  1976年   244篇
  1975年   335篇
  1974年   504篇
  1973年   509篇
  1972年   424篇
  1971年   399篇
  1970年   387篇
  1969年   407篇
  1968年   352篇
  1967年   267篇
  1966年   293篇
  1965年   176篇
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
41.
42.
The clofibric acid (CPIB) concentration in the rat blood plasma during 14 days of treatment with clofibrate and after cessation of the treatment, was measured and compared with the changes of some NADP-linked dehydrogenases activity. CPIB rapidly accumulates in the plasma during the first two days of clofibrate administration reaching a maximum concentration of about 0.6 mM. Then a linear decrease of the drug concentration was observed. The second day after clofibrate treatment had been completed, CPIB could no longer be detected in the plasma. Liver malic enzyme activity increased constantly up to the third day after cessation of the treatment. There was a decrease of activity which reached its control level on the 32nd day of the experiment. The variation patterns of hexose monophosphate shunt dehydrogenases activity and liver weight were similar to the changes of malic enzyme activity.  相似文献   
43.
44.
45.
46.
Microbial transformation of selected azacarbazoles, compounds noted for their activity as antitumor agents, conducted with Kitasatosporia setae strain resulted in N-methylation of pyridine nucleus of alpha-, beta- and gamma-carboline molecule. Formed quaternized intermediates were converted in alkaline conditions into corresponding iso-carbolines. The structure of the final products, alpha-, beta- and gamma-iso-carbolines have been established on the basis of spectral data and confirmed by chemical synthesis.  相似文献   
47.
The paper presents the possibilities of applying the posterior thigh flap in the treatment of ischial pressure sores. Between 2000 and 2004 the flap was used in three cases treated in the Orthopaedics and Traumatology Department of the Medical Universtity in Bialystok. The indications, contraindications, operative technique and advantages of the posterior thigh flap are described. In all three cases the ischial bed sores healed well without recurrences. The posterior fasciocutaneous pedicled flap is a good method of treatment for not too extensive bed sores in the ischial region.This flap can be applied in recurrences found after primary bed sore treatment with another method. However the fasciocutaneous flap has a limited range of transposition as compared with cutaneous flaps.  相似文献   
48.
Violence at the workplace--a questionnaire survey of nurses.   总被引:2,自引:0,他引:2  
BACKGROUND: In the health sector, anywhere in the world nurses are one of the most exposed groups to violence. However, it is not obvious that psychiatric nurses (PNs) are more exposed to aggression and burnout. OBJECTIVES: To determine the nature and effects of aggressive acts towards nursing staff in psychiatric and other medical services in Poland. METHODS: Various questionnaires (Stress at Work Scale, General Health Questionnaire, Maslach Burnout Inventory, Work Satisfaction Scale), were distributed among psychiatric (N=78) and non-psychiatric nurses (N-PNs) (N=335). A 92.6% response rate was achieved. RESULTS: Significant differences were found between PNs and non-psychiatric counterparts with respect to their experiences of violence. The most frequently reported incident was verbal abuse, followed by threats and physical assault. Patients were significantly more frequent perpetrators in psychiatric wards than in others. The level of intra-staff aggression did not significantly vary between groups, neither did the level of work satisfaction and absenteeism. CONCLUSION: The frequency of violent acts and stress related to them point out the strong need for the development of preventive programs to address the issue of violence at work.  相似文献   
49.
In reaction of alpha-phenyl, alpha-p-chlorophenyl and alpha-m-chlorophenylsuccinic acid with various aminopyridines, N-pyridyl-substituted succinimides (compounds 1-14) were obtained. These compounds were investigated for their CNS activity. Compounds 1, 2, 5, 6 and 7 displayed anticonvulsant properties in the maximum electroshock test. Compounds 5 and 6 were also active in the pentetrazole test.  相似文献   
50.
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