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   1294573篇
  免费   99471篇
  国内免费   1697篇
耳鼻咽喉   16785篇
儿科学   41881篇
妇产科学   35645篇
基础医学   193535篇
口腔科学   35525篇
临床医学   120890篇
内科学   254653篇
皮肤病学   27633篇
神经病学   104795篇
特种医学   47970篇
外国民族医学   266篇
外科学   183905篇
综合类   26507篇
现状与发展   3篇
一般理论   594篇
预防医学   107339篇
眼科学   28864篇
药学   94983篇
  6篇
中国医学   2085篇
肿瘤学   71877篇
  2019年   10543篇
  2018年   14161篇
  2017年   10925篇
  2016年   11804篇
  2015年   13642篇
  2014年   18918篇
  2013年   28884篇
  2012年   39541篇
  2011年   42015篇
  2010年   24174篇
  2009年   23304篇
  2008年   39642篇
  2007年   42395篇
  2006年   42099篇
  2005年   41196篇
  2004年   39544篇
  2003年   37942篇
  2002年   36743篇
  2001年   56519篇
  2000年   57541篇
  1999年   48614篇
  1998年   13908篇
  1997年   12626篇
  1996年   13024篇
  1995年   12223篇
  1994年   11395篇
  1993年   10661篇
  1992年   38635篇
  1991年   38057篇
  1990年   36820篇
  1989年   35616篇
  1988年   33008篇
  1987年   32330篇
  1986年   30811篇
  1985年   29049篇
  1984年   22220篇
  1983年   19423篇
  1982年   11591篇
  1979年   21144篇
  1978年   15588篇
  1977年   12957篇
  1976年   12007篇
  1975年   12943篇
  1974年   15754篇
  1973年   15518篇
  1972年   14668篇
  1971年   13665篇
  1970年   12882篇
  1969年   12177篇
  1968年   11336篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Quantitative studies of morbidity, food intake, and somatic growth were done prospectively during 14 mo for 70 children aged 5-18 mo in two Bangladeshi villages. When random-effect regression models were used, monthly changes in weight were inversely related to proportions of days in the month with fever and diarrhea and positively related to energy intake per kilogram body weight. Interestingly, weight changes did not vary with age in this interval. Estimates indicate that increasing energy intakes to the recommended World Health Organization level would have a significantly greater effect on weight gain than would the elimination of diarrhea and fever. With energy at recommended intake and diarrhea and fever prevalence as found in US children, weight gain is predicted to be near that of the international reference population. Therefore, interventions aimed at improving dietary intake may be as important as infection-control programs for improving growth of children in poor developing nations.  相似文献   
992.
Body composition and measures of obesity were evaluated in 59 subjects with myelomeningocele (MMC), aged 0.3-29 y, by anthropometry and measures of body cell mass (BCM) and intra- and extracellular water (ICW and ECW), derived from total body potassium and deuterium-isotope dilution; these results were compared with reference data. Body composition was normal in preambulatory children with MMC. Beyond ages 3-4 y there was significant depletion of BCM and total body water, with maldistribution of water (increased ECW and decreased ICW) and increased percentage body fat above that expected for age and sex. These findings were more pronounced in females and in those with high lesions, and were less pronounced in those who remained ambulatory. These changes may result in metabolic and nutritional maladaption during stress. The relation of BCM, total body water depletion and increased ECW to decreasing ambulatory activity suggests that early nutritional and mobility programs warrant further study.  相似文献   
993.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination.  相似文献   
994.
Unwanted variations in the rules of practice   总被引:1,自引:0,他引:1  
J E Wennberg 《JAMA》1991,265(10):1306-1307
  相似文献   
995.
Many hospitals today have implemented widely disparate information systems on mainframe and mini-computer hardware. The advent of network technology in hospitals has made it possible to access information in these systems. Unfortunately, the user interfaces to applications on these systems are unique and difficult to learn, which makes them unsuitable for use by clinical services. In this paper we describe the development of a Physician's Workstation which integrates information from multiple existing information systems and discuss how the workstation makes it possible to move from the departmental systems of the present to the computer-based medical record system of the future.  相似文献   
996.
997.
Twenty two patients (age range: 1 month to 11 years) were treated for congenital diaphragmatic defects (excluding hiatus hernia) in the six year period 1983-8. Presenting features were failure to thrive (n = 7), abdominal pain and vomiting (n = 4), chronic respiratory symptoms (n = 3), and inability to wean from ventilatory support (n = 3). The defect was an incidental finding in five patients. Operative repair was performed with no mortality or serious postoperative morbidity. Dramatic improvement occurred in 15 of the 17 symptomatic patients. Awareness of the differential diagnosis should avoid delay in diagnosis or inappropriate treatment. Surgical correction is strongly recommended in all cases.  相似文献   
998.
999.
Five cases of unilateral vocal cord paralysis/paresis were diagnosed following extracorporeal membrane oxygenation for newborn respiratory failure. All were right sided and transient in nature. None of the five patients had other findings commonly associated with vocal cord palsy. The extracorporeal membrane oxygenation procedure requires surgical dissection in the carotid sheath on the right side of the neck, an area immediately adjacent to both the vagus and recurrent laryngeal nerve. It is speculated that vocal cord paralysis in these infants was acquired as a result of the extracorporeal membrane oxygenation cannulation. Although the vocal cord paralysis resolved in all cases, two patients had difficult courses after extracorporeal membrane oxygenation. Therefore, laryngoscopic examination should be considered for patients after extracorporeal membrane oxygenation.  相似文献   
1000.
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