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   181257篇
  免费   33263篇
  国内免费   2465篇
耳鼻咽喉   5415篇
儿科学   6256篇
妇产科学   2987篇
基础医学   7595篇
口腔科学   1925篇
临床医学   29464篇
内科学   54486篇
皮肤病学   8111篇
神经病学   17574篇
特种医学   7247篇
外国民族医学   3篇
外科学   45002篇
综合类   615篇
现状与发展   72篇
一般理论   30篇
预防医学   9650篇
眼科学   3905篇
药学   2705篇
  1篇
中国医学   62篇
肿瘤学   13880篇
  2024年   688篇
  2023年   4837篇
  2022年   1319篇
  2021年   3409篇
  2020年   6203篇
  2019年   2518篇
  2018年   7807篇
  2017年   7617篇
  2016年   8739篇
  2015年   8808篇
  2014年   16093篇
  2013年   16572篇
  2012年   6988篇
  2011年   7133篇
  2010年   11328篇
  2009年   15200篇
  2008年   7416篇
  2007年   5810篇
  2006年   8262篇
  2005年   5633篇
  2004年   4755篇
  2003年   3726篇
  2002年   3761篇
  2001年   4398篇
  2000年   3567篇
  1999年   3788篇
  1998年   4053篇
  1997年   3843篇
  1996年   3676篇
  1995年   3516篇
  1994年   2235篇
  1993年   1836篇
  1992年   1872篇
  1991年   1893篇
  1990年   1497篇
  1989年   1572篇
  1988年   1373篇
  1987年   1211篇
  1986年   1221篇
  1985年   1076篇
  1984年   849篇
  1983年   794篇
  1982年   789篇
  1981年   684篇
  1980年   572篇
  1979年   558篇
  1978年   544篇
  1977年   583篇
  1975年   442篇
  1972年   459篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
85.
Three patients with dysphagia caused by compression of the distal esophagus by a tortuous nonaneurysmal atherosclerotic aorta are described. All three patients were elderly women; systemic hypertension and cardiomegaly were present in two patients. Barium studies of the esophagus showed displacement and compression of the distal esophagus by the thoracic aorta. Debilitating dysphagia was treated surgically in one patient. The other two patients had milder symptoms and were managed conservatively. Esophageal manometry in these three patients showed superimposed pulsations and elevated intraluminal pressure just proximal to the lower esophageal sphincter. To evaluate the significance of these manometric findings and their correlation with clinical symptoms, we reviewed manometric tracings in 47 normal subjects. Ten of these subjects had an elevation of baseline intraluminal esophageal pressure as a result of superimposed vascular pulsations. We conclude that (1) compression of the distal esophagus by a tortuous atherosclerotic aorta in the appropriate setting can lead to clinically significant dysphagia and (2) a manometric finding of vascular compression of the esophagus does not necessarily correlate symptomatic dysphagia.  相似文献   
86.
MICHELLE EHRLICH  MD    JAGGI RAO  MD    ANJU PABBY  MD    MITCHEL P. GOLDMAN  MD 《Dermatologic surgery》2006,32(5):618-625
BACKGROUND AND OBJECTIVE: Facial rhytides are a common cosmetic concern. Surgical treatment effects dramatic improvement; however, the associated risk and cost may be prohibitive. Recent focus is on developing topical products containing biologically active ingredients for at-home therapy. Our study examines the effects of a topical cream containing transforming growth factor-beta(1) (TGF-beta(1)), l-ascorbic acid, and Cimicifuga racemosa extract (CRS) (Topix Pharmaceuticals, North Amityville, NY, USA). MATERIALS AND METHODS: In the first arm of the study, 12 subjects were randomized to apply CRS to the left or right side of their face and a cream containing l-ascorbic acid and C. racemosa in silicone base (vitamin C [Vit C]) to the contralateral side twice daily for 3 months. In the second arm of the study, 20 subjects were randomized to apply CRS to the left or right side of their face and Tissue Nutrient Solution Recovery Complex (TNS) (SkinMedica, Carlsbad, CA, USA), a product containing a variety of growth factors including VEGF, PDGF-A, G-CSF, HGF, IL-6, IL-8, and TGF-beta(1) (Nouricel-MD) without l-ascorbic acid, C. racemosa extract, or silicone base, to the contralateral side of their face twice daily for 3 months. Digital photographs were scored by study-blinded physicians, and self-assessments were completed by all subjects at baseline and at the conclusion of the protocol. RESULTS: CRS and TNS were well tolerated, and all subjects completed the 3-month protocol for the CRS versus Vit C arm of the study. Physicians rated success in facial wrinkling scores on the CRS-treated side of the face for 27 of 31 subjects. Responders showed, on average, 21.7% improvement in physician-rated wrinkle scores. The mean improvement in the group of 31 patients as a whole was 12%. Eighteen of 31 subjects reported a noticeable improvement on their CRS-treated side. Both CRS and TNS demonstrate significant success between baseline and 3-month scores, and both growth factor products are superior to Vit C. Patients preferred CRS over TNS. CONCLUSION: CRS is effective in minimizing the appearance of facial rhytides. The success of the CRS product is largely attributable to the incorporation of TGF-beta(1).  相似文献   
87.
88.
89.
90.
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