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   813927篇
  免费   328040篇
  国内免费   62220篇
耳鼻咽喉   8273篇
儿科学   13523篇
妇产科学   6225篇
基础医学   127422篇
口腔科学   13591篇
临床医学   124119篇
内科学   147765篇
皮肤病学   11098篇
神经病学   39048篇
特种医学   32048篇
外国民族医学   51篇
外科学   92392篇
综合类   198814篇
现状与发展   141篇
一般理论   14篇
预防医学   105004篇
眼科学   26288篇
药学   122724篇
  906篇
中国医学   89871篇
肿瘤学   44870篇
  2023年   9613篇
  2022年   22378篇
  2021年   27875篇
  2020年   25793篇
  2019年   22205篇
  2018年   23494篇
  2017年   27391篇
  2016年   23217篇
  2015年   33811篇
  2014年   40649篇
  2013年   46725篇
  2012年   63933篇
  2011年   68852篇
  2010年   64497篇
  2009年   66959篇
  2008年   57394篇
  2007年   52995篇
  2006年   47359篇
  2005年   39439篇
  2004年   31836篇
  2003年   27799篇
  2002年   24213篇
  2001年   23621篇
  2000年   16399篇
  1999年   16258篇
  1998年   15174篇
  1997年   15053篇
  1996年   15849篇
  1995年   15866篇
  1994年   15528篇
  1993年   13960篇
  1992年   13085篇
  1991年   12434篇
  1990年   11344篇
  1989年   11162篇
  1988年   10693篇
  1987年   9993篇
  1986年   9521篇
  1985年   8528篇
  1984年   6597篇
  1983年   6592篇
  1982年   7635篇
  1981年   7167篇
  1980年   6831篇
  1979年   6654篇
  1978年   5841篇
  1977年   6131篇
  1976年   5760篇
  1975年   5499篇
  1974年   5046篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
The effects of danazol on calcium homeostasis in normal postmenopausal women was examined in a 14-day study utilizing a dosage of 800 mg per day. Danazol caused significant falls in plasma ionized calcium and in the fasting urinary calcium/creatinine ratio, indicating inhibition of bone resorption. Retention of phosphate was also observed as expected with this anabolic agent. The plasma total alkaline phosphatase was also depressed by the drug, which had no effect on hepatocellular function as measured by plasma AST. Certain effects induced by treatment with danazol were still apparent two weeks after cessation of treatment. The drug was well tolerated and androgenic side effects were not seen. It is suggested that the minimal dose regimen of danazol which exerts a calcium-sharing effect should be identified, and that this regimen should be considered for use in a prospective study of the effects of danazol on bone mineral content in the postmenopause.  相似文献   
982.
The uptake of the phenanthridinium ethidium by the trypanosomatids Crithidia fasciculata and Leptomonas seymouri was studied. The time course of uptake of ethidium was biphasic for both organisms, consisting of an initial rapid phase and a protracted slow phase. The characteristics of these phases were consistent with the hypothesis that the initial phase represented specific external binding, while the second phase represented transport into the cells. In L. seymouri the transport phase was inhibited by inhibitors of energy transduction and putative inhibitors of a transport ATPase. Ethidium transport could not be saturated over a large concentration range of ethidium. Phenanthridiniums and related compounds displayed both inhibitory and stimulatory effects on ethidium transport.  相似文献   
983.
Novel method for detecting micro-organisms in blood cultures.   总被引:13,自引:3,他引:10       下载免费PDF全文
A method for detecting the growth of micro-organisms in blood culture by a visual signal is described. The system utilises a single blood culture medium that has been specifically formulated to support growth of aerobic, anaerobic, and microaerophilic micro-organisms. The system is based on the principle that when micro-organisms grow in the medium in a sealed bottle their metabolic products create positive pressure. This positive pressure displaces the infected blood and broth into an upper chamber, which acts as a visual signal of microbial activity. All the test micro-organisms, when inoculated at less than 20 colony forming units into simulated human blood cultures, gave a positive signal.  相似文献   
984.
985.
肩关节周围炎的循证针灸治疗   总被引:3,自引:0,他引:3  
何竟  刘屹  吴滨 《中国针灸》2005,25(2):103-106
目的:从循证医学的角度,向临床医生介绍肩关节周围炎的循证针灸治疗方案的确立方法.方法:以一位具体的肩关节周围炎患者为例,介绍如何提出临床问题,怎样检索相关文献,如何对所检索的文献进行评价,如何结合本病例的具体情况和医生的个人经验,运用所检索的证据拟定治疗方案.结果:采用按照循证医学方法确立的肩关节周围炎的针灸治疗方案治疗15次后,患者生活质量明显好转.结论:通过临床提出问题、寻找证据、分析证据、循证决策、循证实践过程,不但患者可达到满意疗效,主管医生也提高了理论水平和临床能力.  相似文献   
986.
OBJECTIVE: According to a report published by the federation of Dutch patients' associations, patients would like to see a pharmacist, who acts more as a personal adviser. This raised the question, how often Dutch community pharmacists have personal consultations with their patients in daily practice, on which factors this depends, and what kind of topics are discussed during these meetings. SETTING: Community pharmacies in the Netherlands. METHOD: A questionnaire was distributed among 800 randomly selected pharmacies. Questions were restricted to consultations characterized by one-to-one contact, drug therapy related content, and adequate privacy. These consultations were labelled as pharmaceutical consultations in private to distinguish them from other contacts between pharmacists and patients. MAIN OUTCOME MEASURE: Number, content, and character of consultations. RESULTS: 198 (24.8%) community pharmacies responded. The pharmacists provide an average of roughly 1.2 consultations in private per working day. The vast majority of respondents provided face-to-face and telephone consultations (94.4 and 91.9%, respectively), only a minority gave consultations by e-mail (30.8%). These consultations primarily dealt with topics related to medication safety. The mean overall time spent was 290 min per month. A relatively high frequency of personal consultations was significantly associated with the absolute number of full-time equivalent pharmacists in the pharmacy. CONCLUSION: The frequency of pharmaceutical consultations in private is low, but may be improved by reorganisation of the pharmacist's activities. The possibility of personal consultations by e-mail is not yet well-developed. Further research is needed to assess the patient's view of pharmaceutical consultations in private.  相似文献   
987.
988.
38例视网膜母细胞瘤的临床和误诊分析   总被引:1,自引:0,他引:1  
目的 探讨视网膜母细胞瘤(retinoblastoma,RB)的临床特征、病理分类和误诊原因,尽可能减少错误的临床诊治。方法 对我科于1999-2004年间收集的38例临床诊断为视网膜母细胞瘤(retinoblastoma,RB)的病例资料进行回顾性分析。结果在38例疑似病例中,34例病理诊断为视网膜母细胞瘤,4例为Coats病。结论掌握相关的影像学知识和综合分析疑难病例的临床资料将有助于视网膜母细胞瘤的正确诊断和处理。  相似文献   
989.
990.
经颅彩色双功超声是一种新型、无创的超声诊断仪,高空间分辨率显示颅内血管和脑实质的结构,笔者查阅了近年来相关文献,主要综述经颅彩色多普勒血流显像在颅脑血管疾病中的诊断价值,同时讨论二维经颅超声的应用及新的实验性显像技术。  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