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   1542253篇
  免费   100732篇
  国内免费   2073篇
耳鼻咽喉   20990篇
儿科学   51807篇
妇产科学   43102篇
基础医学   218392篇
口腔科学   40195篇
临床医学   128196篇
内科学   298459篇
皮肤病学   30404篇
神经病学   125481篇
特种医学   62610篇
外国民族医学   374篇
外科学   240110篇
综合类   29240篇
现状与发展   1篇
一般理论   337篇
预防医学   115151篇
眼科学   33948篇
药学   113740篇
  1篇
中国医学   3255篇
肿瘤学   89265篇
  2018年   34601篇
  2017年   26941篇
  2016年   30703篇
  2015年   14668篇
  2014年   19089篇
  2013年   29315篇
  2012年   45501篇
  2011年   61594篇
  2010年   42170篇
  2009年   32951篇
  2008年   59265篇
  2007年   64387篇
  2006年   45300篇
  2005年   45965篇
  2004年   45366篇
  2003年   45335篇
  2002年   42895篇
  2001年   62059篇
  2000年   64657篇
  1999年   53510篇
  1998年   15491篇
  1997年   13912篇
  1996年   13833篇
  1995年   13007篇
  1994年   12416篇
  1993年   11467篇
  1992年   41571篇
  1991年   40915篇
  1990年   40489篇
  1989年   39243篇
  1988年   36564篇
  1987年   35831篇
  1986年   34124篇
  1985年   32695篇
  1984年   24420篇
  1983年   21283篇
  1982年   12846篇
  1981年   11354篇
  1979年   23012篇
  1978年   16232篇
  1977年   14095篇
  1976年   13269篇
  1975年   14528篇
  1974年   17020篇
  1973年   16342篇
  1972年   15531篇
  1971年   14454篇
  1970年   13440篇
  1969年   12941篇
  1968年   12176篇
排序方式: 共有10000条查询结果,搜索用时 421 毫秒
91.
92.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
93.
94.
95.
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications.  相似文献   
96.
97.
Advancing nanomedicines from concept to clinic requires integration of new science with traditional pharmaceutical development. The medical and commercial success of nanomedicines is greatly facilitated when those charged with developing nanomedicines are cognizant of the unique opportunities and technical challenges that these products present. These individuals must also be knowledgeable about the processes of clinical and product development, including regulatory considerations, to maximize the odds for successful product registration. This article outlines these topics with a goal to accelerate the combination of academic innovation with collaborative industrial scientists who understand pharmaceutical development and regulatory approval requirements—only together can they realize the full potential of nanomedicines for patients.  相似文献   
98.
99.
100.
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