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   274071篇
  免费   45759篇
  国内免费   12846篇
耳鼻咽喉   3953篇
儿科学   4353篇
妇产科学   4637篇
基础医学   23730篇
口腔科学   8210篇
临床医学   49042篇
内科学   49930篇
皮肤病学   5334篇
神经病学   21054篇
特种医学   9851篇
外国民族医学   97篇
外科学   35467篇
综合类   29683篇
现状与发展   79篇
一般理论   22篇
预防医学   25142篇
眼科学   6789篇
药学   20484篇
  191篇
中国医学   10964篇
肿瘤学   23664篇
  2024年   1434篇
  2023年   7826篇
  2022年   8816篇
  2021年   12335篇
  2020年   12474篇
  2019年   8169篇
  2018年   13225篇
  2017年   13171篇
  2016年   13338篇
  2015年   16457篇
  2014年   20633篇
  2013年   21462篇
  2012年   17565篇
  2011年   18447篇
  2010年   16296篇
  2009年   16332篇
  2008年   13137篇
  2007年   11563篇
  2006年   12371篇
  2005年   10669篇
  2004年   6898篇
  2003年   6069篇
  2002年   5122篇
  2001年   5367篇
  2000年   4897篇
  1999年   5489篇
  1998年   4314篇
  1997年   4205篇
  1996年   3694篇
  1995年   3391篇
  1994年   2573篇
  1993年   1800篇
  1992年   2005篇
  1991年   1729篇
  1990年   1387篇
  1989年   1345篇
  1988年   1250篇
  1987年   989篇
  1986年   800篇
  1985年   680篇
  1984年   433篇
  1983年   453篇
  1982年   312篇
  1981年   315篇
  1980年   195篇
  1979年   168篇
  1978年   171篇
  1977年   165篇
  1976年   125篇
  1974年   114篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Psychological Consequences of Food Restriction   总被引:1,自引:0,他引:1  
A review of the literature and research on food restriction indicates that inhibiting food intake has consequences that may not have been anticipated by those attempting such restriction. Starvation and self-imposed dieting appear to result in eating binges once food is available and in psychological manifestations such as preoccupation with food and eating, increased emotional responsiveness and dysphoria, and distractibility. Caution is thus advisable in counseling clients to restrict their eating and diet to lose weight, as the negative sequelae may outweigh the benefits of restraining one's eating. Instead, healthful, balanced eating without specific food restrictions should be recommended as a long-term strategy to avoid the perils of restrictive dieting. J Am Diet Assoc. 1996; 96:589-592.  相似文献   
32.
Summary: This is the first report of the largest study of blood pressure measurement in pregnancy in a New Zealand population using standardized definitions and methodology. Over 3,800 women who delivered in an 8-month period in the Wellington region were included in the study. Blood pressure measurement and the presence of oedema and proteinuria were recorded from booking until delivery and in the puerperium. Only 2.7% of women were unable to be contacted after delivery for details on outcomes. The results established normal ranges for blood pressure throughout pregnancy. The data show that Mood pressure greater than 140/90 until 35 weeks' gestation is outside 2 standard deviations at all gestations and justifies using these measurements as the definition of hypertension in pregnancy. The fall in blood pressure in the 2nd trimester was less than 1 mm Ffg per week in both the systolic and diastolic pressures. This fall was smaller than previously recorded in other studies. Gestational hypertension was the commonest blood pressure abnormality occurring in 15.2% of the population. This represented 69% of the pregnant women with a hypertensive disorder. The overall incidence of both gestational hypertension and preeclampsia was 18.5% which is higher than reported in other parts of the world. In this study obesity was significantly associated with hypertensive disorders in pregnancy. An arm circumference of >33 cm, one of the measurements of obesity, was found in 6.8% of the study population. Even after the effect of arm circumference was taken into account, hypertensive disorders were also more common in Pacific Island women. Ankle oedema was significantly associated with the development of both gestational hypertension and preeclampsia but the incidence of oedema was noted in only 11.9% of the subjects.  相似文献   
33.
Entering the postmodern world in which society is confronting crossroads, paradoxes, and complexity, the health care system is encountering a transformation more comprehensive and revolutionary than has ever been seen before. Analysis of the state of nursing vis a vis these transformations indicates that the current paradigm does not ensure the existence of the profession in the postmodern health care system. That is because of increased difficulties in consolidating the economic and quality issues into the core of nursing, and in understanding the complexity inherent in health related situations.  相似文献   
34.
35.
Society often expects mothers and fathers to share equally in the perinatal grief process because the child was a common bond between them. Unfortunately, in perinatal grief, this is not always the case. The mother and the father can experience incongruent grieving and use discordant coping mechanisms. It is important to evaluate these differences to facilitate communication between the distraught parents. Improved communication can in turn facilitate the grieving process.  相似文献   
36.
37.
38.
OBJECTIVE: To understand the role of nasal mucous epithelial cells to hypoxia in early stage of nasal polyps(NP) formation. METHODS: Epithelial cells of NP and inferior turbinate (IT) were cultured without serum under normal oxygen and hypoxia, and stimulus of inflammatory cytokines. Erythropoietin (EPO) was regarded as hypoxia mark, and expression of vascular endothelial growth factor(VEGF) mRNA and protein derived from epithelial cells were detected respectively by in situ hybridization and ELISA. RESULTS: 1. Under hypoxia, EPO mRNA was expressed intensely in epithelial cells from NP and IT, and there was no significant difference between both of them. This result suggested that EPO might be regarded as a hypoxic mark. 2. The ability of producing VEGF mRNA increased with cytokines stimulation, especially under hypoxia. Protein level of VEGF from epithelial cells of NP and IT increased with cytokines stimulation, especially in hypoxia and was time-dependent. CONCLUSION: Epithelial cells actively produce vast VEGF under hypoxia. The VEGF induced by hypoxia of the mucosa in middle meatus is of importance in the formation of nasal polyps(NP) in early stage, which may be the major cause of NP formation in middle meatus.  相似文献   
39.
40.
本文报道了气管切开术各种并发症的发病率,并对术中或术后并发症的病的病因、发病机理、治疗和预防进行了讨论。  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