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   212105篇
  免费   15457篇
  国内免费   5103篇
耳鼻咽喉   2917篇
儿科学   5467篇
妇产科学   3378篇
基础医学   21891篇
口腔科学   6182篇
临床医学   19076篇
内科学   40019篇
皮肤病学   5207篇
神经病学   12270篇
特种医学   6520篇
外国民族医学   1篇
外科学   23216篇
综合类   22180篇
现状与发展   13篇
一般理论   36篇
预防医学   23920篇
眼科学   3854篇
药学   17599篇
  119篇
中国医学   9030篇
肿瘤学   9770篇
  2024年   563篇
  2023年   2209篇
  2022年   3239篇
  2021年   6053篇
  2020年   4492篇
  2019年   4536篇
  2018年   7122篇
  2017年   5626篇
  2016年   4905篇
  2015年   6764篇
  2014年   8025篇
  2013年   11176篇
  2012年   16584篇
  2011年   17565篇
  2010年   12111篇
  2009年   10002篇
  2008年   14066篇
  2007年   14349篇
  2006年   13036篇
  2005年   11804篇
  2004年   9685篇
  2003年   8737篇
  2002年   7876篇
  2001年   5610篇
  2000年   5663篇
  1999年   3886篇
  1998年   909篇
  1997年   730篇
  1996年   718篇
  1995年   577篇
  1994年   442篇
  1993年   418篇
  1992年   1417篇
  1991年   1178篇
  1990年   1048篇
  1989年   904篇
  1988年   760篇
  1987年   727篇
  1986年   727篇
  1985年   623篇
  1984年   465篇
  1983年   378篇
  1979年   356篇
  1975年   283篇
  1974年   321篇
  1973年   352篇
  1972年   305篇
  1971年   330篇
  1970年   297篇
  1969年   296篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
自杀行为及其干预的研究进展   总被引:15,自引:1,他引:14  
自杀已经成为一个世界范围内的重大公共卫生问题。中国的自杀特征具有独特性。自杀行为的发生往往是内在因素与外部因素相互作用的结果,它与社会学、心理学、伦理学、生物学、精神病学等各方面密切相关。自杀原因虽然错综复杂,但我们要提高意识,认识到自杀是一种可以预防的公共卫生问题。  相似文献   
82.
本文针对Orso元数据方法的不足,对构件可能的变更进行了充分分析和分类,并按照分类情况对相关的构件变更处理方法进行了详尽的形式化描述,构造了构件变更模型,描述了每个变更的具体表现形式,论述了方法变更到构件接口变更的映射机制和算法,给出了算法实现的框架,并将这些理论模型应用到自主开发的构件RegisterStuGrade中,与没有元数据情况下的回归测试用例生成技术以及Orso方法进行回归测试用例数和回归测试运行时间两方面的分析和对比,给出了比较结果.  相似文献   
83.
84.
85.
1临床资料 患者,女,43岁,因车祸致右胫腓骨骨折入住我院创伤骨科,一般情况良好,无食物、药物过敏史,入院后行腓骨复位固定术,3d后,伤口红肿并有脓液渗出,为预防和控制感染,静脉滴注硫酸奈替米星葡萄糖注射液每日200mL(每瓶100mL,硫酸奈替米星10万u,约相当于0.1g,葡萄糖5.0g,山东鲁抗辰欣药业有限公司,批号0803155209)分两次滴注,中间滴注含有4mL复方维生素注射液的10%葡萄糖注射液500mL(四川美大康佳乐有限公司,批号080125124)。  相似文献   
86.
Background and objectiveTo analyse frequency, characteristics and patient survival with lung cancer (LC) and Common Obstructive Pulmonary Disease (COPD), comparing them with patients that do not have COPD.Material and methodsA retrospective study, of patients diagnosed by means of cytohistology. Survival was estimated by the Kaplan-Meier method. Statistical analysis was carried out using SPSS 15.0.ResultsA total of 996 patients were diagnosed, 39.8% with COPD. Mean age70±9.19 years. GOLD stages: I 18.2%, II 53.6%, III 24%, IV 4.2%. The histological types: squamous cell carcinoma 48.2%, adenocarcinoma 22%, and small cell carcinoma 22.5%. Survival was longer in the COPD group.ConclusionsLC and COPD are combined in 39.8%. Squamous cell type is more frequent and survival was longer in the COPD group.  相似文献   
87.
Background and ObjectiveSchool smoking prevention programs have never yielded the expected results. The aim of this study was to analyze the efficacy of an intensive smoking prevention program created by the educational community in which it was to be applied.Population and MethodA 3-year smoking prevention program was carried out among the students of Fuentesaúco Secondary School in Zamora, Spain. The Babilafuente Secondary School in Salamanca, Spain was the control group. The program included both prevention and treatment activities. The former were carried out in the school, in out-of-school situations, and in the community. The questionnaire of the European Smoking Prevention Framework Approach was used.ResultsA total of 417 students aged 12 to 17 years participated in the study. Of these, 54.4% belonged to the intervention group and 45.6% to the control group. Smokers represented 36.7% of the population. After the intervention smokers represented 40.1% of the Fuentesaúco students compared with 46.1% of the Babilafuente students, though the difference was not statistically significant. With respect to the cognitive determinants of smoking behavior, after the intervention significant differences in favor of the intervention group were only observed in the subjects’ perception of the behavior of their siblings, peers, and teachers.ConclusionsThe use of smoking prevention programs in schools should be reconsidered, and their evaluation should be based on educational rather than clinical criteria. Proposed changes in the program include decreasing its intensity, starting with students of an earlier age and seeking greater involvement of parents.  相似文献   
88.
89.
ObjectiveTo assess whether the release of the new consensus algorithms in August 2006, along with the consensus recommendation of also using metformin as first choice in patients with normal weight, has led to an increase in the use of this drug in the period immediately after.DesignRetrospective longitudinal Study.SitesSantiago de Compostela Health District (A Coruña).ParticipantsUsers of the Galician health service in the Santiago de Compostela Health District.MethodsThe evolution of the monthly number of DHD (Daily Defined Doses/1000 inhabitants/day) of metformin from early 2003 until 12 months after the issuing of new algorithms was analysed graphically and using a multiple regression model.ResultsThe graphical representation of the DHD of metformin over time shows a linear growth for the period, but there is an increasing trend after the publication of the new consensus algorithm. The multiple regression showed that the increase is statistically significant.ConclusionsFollowing the publication of the new consensus algorithm an increasing trend in the use of metformin is observed in the short term.  相似文献   
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