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   154111篇
  免费   31403篇
  国内免费   2408篇
耳鼻咽喉   5184篇
儿科学   5502篇
妇产科学   2550篇
基础医学   3488篇
口腔科学   1504篇
临床医学   27368篇
内科学   47830篇
皮肤病学   7478篇
神经病学   15039篇
特种医学   6388篇
外科学   41090篇
综合类   276篇
现状与发展   72篇
一般理论   7篇
预防医学   7583篇
眼科学   3400篇
药学   1208篇
中国医学   14篇
肿瘤学   11941篇
  2024年   687篇
  2023年   4808篇
  2022年   1246篇
  2021年   3184篇
  2020年   6100篇
  2019年   2276篇
  2018年   7470篇
  2017年   7413篇
  2016年   8479篇
  2015年   8476篇
  2014年   15587篇
  2013年   15804篇
  2012年   5746篇
  2011年   5739篇
  2010年   10488篇
  2009年   14344篇
  2008年   6045篇
  2007年   4262篇
  2006年   6724篇
  2005年   3998篇
  2004年   3257篇
  2003年   2209篇
  2002年   2247篇
  2001年   3795篇
  2000年   3000篇
  1999年   3213篇
  1998年   3680篇
  1997年   3477篇
  1996年   3379篇
  1995年   3229篇
  1994年   1943篇
  1993年   1571篇
  1992年   1374篇
  1991年   1404篇
  1990年   1057篇
  1989年   1175篇
  1988年   1017篇
  1987年   848篇
  1986年   883篇
  1985年   716篇
  1984年   546篇
  1983年   522篇
  1982年   515篇
  1981年   401篇
  1980年   364篇
  1979年   306篇
  1978年   333篇
  1977年   397篇
  1975年   278篇
  1972年   302篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
103.
104.
105.
106.
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   
107.
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   
108.
109.
110.
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