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   57492篇
  免费   3793篇
  国内免费   173篇
耳鼻咽喉   772篇
儿科学   1643篇
妇产科学   1031篇
基础医学   6890篇
口腔科学   920篇
临床医学   5815篇
内科学   12529篇
皮肤病学   984篇
神经病学   5185篇
特种医学   2448篇
外国民族医学   1篇
外科学   9743篇
综合类   665篇
一般理论   51篇
预防医学   3633篇
眼科学   1116篇
药学   3393篇
中国医学   50篇
肿瘤学   4589篇
  2023年   259篇
  2022年   443篇
  2021年   1161篇
  2020年   688篇
  2019年   1179篇
  2018年   1394篇
  2017年   1029篇
  2016年   1048篇
  2015年   1258篇
  2014年   1935篇
  2013年   2524篇
  2012年   4035篇
  2011年   4189篇
  2010年   2315篇
  2009年   2018篇
  2008年   3707篇
  2007年   3890篇
  2006年   3900篇
  2005年   3824篇
  2004年   3642篇
  2003年   3400篇
  2002年   3116篇
  2001年   644篇
  2000年   517篇
  1999年   660篇
  1998年   650篇
  1997年   537篇
  1996年   414篇
  1995年   447篇
  1994年   404篇
  1993年   353篇
  1992年   459篇
  1991年   412篇
  1990年   365篇
  1989年   379篇
  1988年   339篇
  1987年   313篇
  1986年   299篇
  1985年   301篇
  1984年   333篇
  1983年   322篇
  1982年   276篇
  1981年   253篇
  1980年   203篇
  1979年   214篇
  1978年   162篇
  1977年   142篇
  1976年   121篇
  1974年   115篇
  1973年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
Mg-, Ca-, Na-, K-ATPase, acetylcholine esterase and sulfhydryl groups of red blood cell membranes were evaluated in 40 patients with chronic glomerulonephritis in preazotemia stage versus 34 healthy controls. In chronic glomerulonephritis there was a significant fall in Ca-ATPase activity irrespective of the disease pattern. Na, K-ATPase tended tot a decrease contrary to sulfhydryl groups levels and acetylcholine esterase activity. In the nephrotic variant of the disease Na, K-ATPase, Ca-ATPase activity dropped and came to increase due to glucocorticosteroid treatment. The changes are attributed to modification of the lipid bilayer of the red blood cell membranes.  相似文献   
44.
45.
B K Rubin  D W Geiger 《Chest》1991,100(3):649-654
Children with cystic fibrosis (CF) often attend special summer camps. We postulated that beyond the simple fun of camp, attendance at camp might improve the clinical status and self-image of the campers. We therefore studied lung function, nutrition, and self-image in 45 children between the ages 6 and 12 years after a two-week CF summer camp. Although there was a 10 percent fall in respiratory rate during camp, spirometry did not change significantly. There were, however, significant gains in weight, skin fold thickness, and midarm circumference after two weeks at camp, and these increases were positively correlated with the number of pancreatic enzymes taken daily by the child. The Primary Self-Concept Inventory test was completed by each camper on the first and last days of camp. Although there was a trend toward increasing self-concept during camp, this did not reach statistical significance. Two weeks' attendance at summer camp appears to be associated with improved nutrition in children with CF. This may be due to increased emphasis on weight gain and appropriate use of pancreatic enzymes or to other factors, like avoidance of tobacco smoke exposure, that are unique to the summer camp setting.  相似文献   
46.
In the cerebellar type of multiple system atrophy (MSA-C), the burden of pathological changes involves the cerebellum and its associated brainstem structures in the basis pontis and the inferior olivary nucleus, and as a result, the clinical phenotype is dominated early on by the cerebellar dysfunction. We report our clinical and post mortem findings in a patient with MSA-C who exhibited pathological laughter in the absence of any congruent changes of mood. A review of the clinical notes of 27 other patients with MSA-C revealed a problem with pathological laughter, or crying, or both in 9 more patients. Our finding of about 36% occurrence suggests that the problem of dysregulation of emotional expression is more prevalent in MSA-C than the paucity of reports in the literature suggests. Our findings are consistent with the view that the cerebellum and its interconnected structures may be involved in the regulation of emotional expression.  相似文献   
47.
OBJECTIVE: To determine how knowledgeable physicians are regarding the toxic effects and drug interactions of herbal remedies. METHODS: An anonymous voluntary demographic survey and 16-question, multiple-choice quiz was distributed at educational meetings of emergency medicine and internal medicine physicians. The primary outcome measures were to determine whether significant associations existed between quiz scores and the amount of clinical experience, or between quiz scores and self-assessed familiarity with the topic of herbal toxicities and adverse herb-drug interactions. RESULTS: A total of 142 surveys and quizzes were completed by 59 attending physicians, 57 resident physicians, and 26 medical students. The mean subject score on the quiz was only slightly higher than would have occurred from random guessing. Neither the amount of the subjects' clinical experience, nor their self-assessed familiarity with herbal toxicities and drug interactions correlated significantly with the score on the quiz. CONCLUSION: The physicians and medical students surveyed had little training in herbal toxicities and drug interactions. They generally rated their familiarity with these topics as 'poor', and their scores on the quiz bore out this assessment as correct. Educational efforts might improve physician knowledge of the adverse effects of herbal remedies.  相似文献   
48.
49.
50.
BACKGROUND AND OBJECTIVE: The adverse effects of untreated seasonal allergic rhinitis (AR) on performance in the workplace, school, and home are poorly understood. To delineate more clearly the impact and consequences of the disease on performance, the effect of symptomatic AR on vigilance and a wide range of cognitive functions was investigated. METHODS: A battery of automated neuropsychological tests was administered to asymptomatic adult subjects with histories of AR. Subjects were randomized to either a symptomatic or to an asymptomatic group. Subjects in the symptomatic group were exposed to ragweed pollen in a controlled exposure setting until they demonstrated predetermined severities of AR symptoms. Subjects in the asymptomatic group were not exposed to ragweed pollen in the environmental unit and retained a minimum symptom profile. The battery of cognitive measures was re-administered to both groups. RESULTS: AR had major adverse impacts on measures of vigilance. Further, AR adversely affected a broad range of cognitive functions. Specifically, subjects with AR symptoms demonstrated longer response times and decreased efficiency on measures of working memory, psychomotor speed, reasoning/computation, and divided attention as compared with asymptomatic subjects. CONCLUSIONS: In addition to decreased vigilance, AR was associated with decrements in speed and efficiency across several cognitive domains. This is similar to findings in research on medications and medical conditions that cause sedation. Findings may represent a link between AR and poor productivity/personal safety among AR sufferers. This suggests that these results have implications with regard to public health.  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