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   367019篇
  免费   23715篇
  国内免费   8491篇
耳鼻咽喉   4263篇
儿科学   9737篇
妇产科学   6713篇
基础医学   29288篇
口腔科学   8449篇
临床医学   39724篇
内科学   44617篇
皮肤病学   4738篇
神经病学   20321篇
特种医学   8633篇
外国民族医学   32篇
外科学   40654篇
综合类   56514篇
现状与发展   13篇
一般理论   33篇
预防医学   38104篇
眼科学   5652篇
药学   32676篇
  450篇
中国医学   34585篇
肿瘤学   14029篇
  2024年   1198篇
  2023年   5895篇
  2022年   10486篇
  2021年   14227篇
  2020年   13288篇
  2019年   18971篇
  2018年   16599篇
  2017年   13641篇
  2016年   11194篇
  2015年   10482篇
  2014年   21596篇
  2013年   22863篇
  2012年   19802篇
  2011年   21868篇
  2010年   17987篇
  2009年   15976篇
  2008年   15456篇
  2007年   15938篇
  2006年   14038篇
  2005年   12127篇
  2004年   9817篇
  2003年   8636篇
  2002年   6745篇
  2001年   6003篇
  2000年   4945篇
  1999年   4270篇
  1998年   3431篇
  1997年   3264篇
  1996年   2815篇
  1995年   2706篇
  1994年   2608篇
  1993年   2062篇
  1992年   2118篇
  1991年   1816篇
  1990年   1624篇
  1989年   1425篇
  1988年   1358篇
  1985年   3876篇
  1984年   4884篇
  1983年   3402篇
  1982年   3894篇
  1981年   3621篇
  1980年   3223篇
  1979年   2962篇
  1978年   2595篇
  1977年   1953篇
  1976年   2195篇
  1975年   1658篇
  1974年   1450篇
  1973年   1295篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Newer policies of community care for those with disabilities have resulted in the home becoming the usual site of care. Policy makers must now give attention to the needs of those at home giving this care. This article explores the constraints on sociability opportunities of 73 mothers who were caring for children with disabilities. These opportunities are often built into leisure pursuits for women without caring responsibilities. However, choice of out-of-house leisure activity was circumscribed for the mothers in this study and their reported leisure activities revolved around home and neighbourhood. Even these sites offered limited scope for sociability because of the way in which caring affected domestic space and because of the characteristics of the modern Australian suburb. It is argued in this paper that personal time and personal domestic space are needed by care-givers so their sociability needs can be fulfilled. An understanding of the constraints imposed by use of the home as a place of care may make possible the planning of a rearrangement of domestic space to increase sociability opportunities for carers.  相似文献   
72.
PURPOSE: This study was undertaken to clarify the importance of bleeding vascular ectasia of the colon as the etiology of massive lower gastrointestinal hemorrhage in patients 40 years of age or younger. METHODS: An otherwise healthy 21-year-old male was admitted to a tertiary medical center with massive lower gastrointestinal hemorrhage. Technetium-labeled red blood cell scan, selective visceral angiography, and colonoscopy identified the source of bleeding as vascular abnormality of the descending colon. Segmental colonic resection was performed. RESULTS: Histologic review of the specimen demonstrated a vascular ectasia. The patient recovered uneventfully and has had no further stigmata of hemorrhage. A review of the literature was undertaken to make clear the significance of vascular ectasia as the source for massive colonic hemorrhage in the young adult. CONCLUSION: This is the first report that documents histologically a vascular ectasia as the source of massive lower gastrointestinal hemorrhage in an otherwise healthy patient less than 40 years of age. Vascular ectasia is an uncommon cause of lower gastrointestinal hemorrhage in the young adult.The Chief, Bureau of Medicine and Surgery, Navy Department, Washington, DC, Clinical Investigation Program sponsored this report #84-16-1968-532, as required by HSETCINST 6000.41A. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government.  相似文献   
73.
本文分析了460例胃癌胃粘膜活检资料,结果:男:女为2.36:1:51~60岁年龄组发病率最岛(37.17%);发生部位以胃窦部最多见,占46.74%;组织学分类以低分化腺癌最多,占51 52%;在伴随病变中,畅化生的检出率为21.74%,胃腺囊为35%,胃粘膜上皮异型增生为32.61%。本组材料提示,不完全性大肠型肠化生、异型胃腺囊及胃粘膜中度以上异型增生与胃癌有密切关系。  相似文献   
74.
74例小儿慢性头痛经辨证治疗,显效80.95%,好转16.67%,无效2.38%。痰浊头痛二陈汤或半夏白术天麻汤加减;肾虚头痛,杞菊地黄汤加减;淤血头痛,补阳还五汤;气血虚头痛八珍汤加减。指出了小儿内伤头痛的病因病机,并指出脑电图,脑阻抗血流图、CT、甲皱微循环可做为此病的诊断及疗效指标。  相似文献   
75.
76.
医药行业科技成果产业化与其他行业科技成果转化相比具有更高的风险,转化能力也是最低的,因此,对其从事前、事中、事后三方面加强风险控制具有重要的观实意义。  相似文献   
77.
Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80 pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower dose levels, the peptide also inhibits basal glucagon release.  相似文献   
78.
Advanced malignant melanomas of the uvea unsuited for an eye salvaging approach require enucleation of the tumor containing eye. A series of 68 patients is reported who underwent enucleation combined with insertion of a spherical dura-encased implant after 30 Gray pre-irridiation therapy of the orbit. Postoperative results with special attention to cosmetic outcome and motility of the prosthesis suggest that the insertion of an orbital implant should be preferred to the enucleation with no implant.  相似文献   
79.
经尿道前列腺电切气化术治疗前列腺增生568例报告   总被引:13,自引:0,他引:13  
目的 :进一步探讨前列腺增生 (BPH)的有效手术新方法。方法 :采用经尿道前列腺电切术和气化术治疗BPH患者 5 6 8例。结果 :疗效满意 ,术后 3~ 6个月随访 ,国际前列腺症状评分 (IPSS) 8.5± 1.5分 ;最大尿流率 (Q max) 2 0 .5± 4 .5ml s,剩余尿量 2 9.1± 14 .2ml,未出现严重并发症。结论 :将电切和气化相结合行经尿道前列腺切除术是一种安全性高、并发症少、疗效确切的新手术方法 ,具有操作易掌握、出血少、速度快、安全可靠等优点。  相似文献   
80.
重庆市城市居民1991~2000年死亡损失生命年分析   总被引:1,自引:0,他引:1  
目的:研究重庆市城市居民20世纪90年代疾病所致早死的生命损失。方法:用死亡损失生命年YLLs为测量单位,计算不同性别、不同社区的死因别标化YLLs率,及分析1991~2000年死因别标化YLLs率的变化趋势。结果:非传染性疾病标化YLLs率为42.58‰,占全死因的82.76%,其中,恶性肿瘤标化YLLs率为12.80‰,占30.06%,脑血管疾病标化YLLs率 6.62‰,占15.55%,呼吸系统疾病标化YLLs率5.77‰,占13.55%,心脏病标化YLLs率4.38‰,占10.29%;意外死亡标化YLLs率为7.59‰,占全死因的14.75%;传染病、妇科及围产期疾病标化YLLs率为1.28‰,仅占2.49%。在社区之间,死因别标化YLLs率存在明显差异。结核病和精神病标化YLLs率曾出现上升趋势。结论:非传染性疾病已成为该城市居民的主要疾病负担,结核病防治不能放松,精神卫生工作急待开展。  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