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   85206篇
  免费   6273篇
  国内免费   2072篇
耳鼻咽喉   1349篇
儿科学   1450篇
妇产科学   2550篇
基础医学   11498篇
口腔科学   1525篇
临床医学   8485篇
内科学   16104篇
皮肤病学   1944篇
神经病学   5575篇
特种医学   4240篇
外国民族医学   6篇
外科学   11425篇
综合类   4264篇
现状与发展   8篇
一般理论   15篇
预防医学   4128篇
眼科学   2163篇
药学   7267篇
  20篇
中国医学   1978篇
肿瘤学   7557篇
  2023年   573篇
  2022年   1862篇
  2021年   3051篇
  2020年   1756篇
  2019年   2281篇
  2018年   2746篇
  2017年   2103篇
  2016年   2476篇
  2015年   3565篇
  2014年   4318篇
  2013年   4974篇
  2012年   7052篇
  2011年   6761篇
  2010年   4329篇
  2009年   3741篇
  2008年   4861篇
  2007年   4815篇
  2006年   4463篇
  2005年   4074篇
  2004年   3552篇
  2003年   3322篇
  2002年   2935篇
  2001年   1974篇
  2000年   1703篇
  1999年   1411篇
  1998年   621篇
  1997年   515篇
  1996年   462篇
  1995年   410篇
  1994年   378篇
  1993年   271篇
  1992年   734篇
  1991年   609篇
  1990年   555篇
  1989年   508篇
  1988年   437篇
  1987年   447篇
  1986年   366篇
  1985年   302篇
  1984年   243篇
  1983年   199篇
  1982年   124篇
  1981年   133篇
  1980年   105篇
  1979年   209篇
  1978年   168篇
  1977年   107篇
  1976年   110篇
  1975年   103篇
  1974年   100篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.

Context

Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.

Objectives/Methods

We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.

Results

Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.

Conclusion

Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months.  相似文献   
32.
33.
Recent studies have reported an association between gastroesophageal reflux disease (GERD) and atrial fibrillation (AF). The objective of the present study was to evaluate whether AF is one of the risk factors for GERD occurrence.In this hospital-based, retrospective, case–control study, the patients were classified into 2 groups. The patients diagnosed with new AF were assigned to the AF group (n = 1612); those diagnosed without AF and GERD were assigned to the control group (n = 1612). The subjects in the control group were selected from outpatients of total healthcare center without a history of AF or GERD, and matched for age and gender. We evaluated the incidence of GERD and risk factors for GERD occurrence between the 2 groups.The number of patients experiencing occurrence of GERD during the follow-up period was significantly higher in the AF group than those in the control group, respectively (129 patients vs 98 subjects, P = 0.037). The incidence of GERD was significantly higher in the AF group than in the control group by Kaplan–Meier analysis with log-rank test (P = 0.008). The AF group''s adjusted hazard ratio of GERD occurrence against that of the control group was 1.37 (95% confidence interval [CI]: 1.16–1.57; P = 0.009) according to Cox''s proportional hazard model.The presence of AF appears to increase the incidence of GERD and may be considered a risk factor for the development of GERD. Further, large prospective and cohort studies will be required to better establish the correlation of GERD with AF.  相似文献   
34.
35.
36.
37.
38.
39.
梁畅  张伟 《现代肿瘤医学》2020,(11):1958-1962
我国乳腺癌的发病率占女性恶性肿瘤疾病的首位,结构扭曲病变(architectural distortion,AD)作为触诊阴性乳腺癌的第三最常见影像学表现,也是乳腺癌最早出现的征象,具有重要的临床价值。AD具有较高的漏诊率及假阳性率。本文通过查阅文献,针对超声、乳腺X线摄影、乳腺数字三维断层摄影技术及核磁共振成像技术在乳腺结构扭曲病变中的研究进展及优缺点进行分析,进一步指导科学研究及临床工作。  相似文献   
40.
Resident and inflammatory macrophages are essential effectors of the innate immune system. These cells provide innate immune defenses and regulate tissue and organ homeostasis. In addition to their roles in diseases such as cancer, obesity and osteoarthritis, they play vital roles in tissue repair and disease rehabilitation. Macrophages and other inflammatory cells are recruited to tissue injury sites where they promote changes in the microenvironment. Among the inflammatory cell types, only macrophages have both pro-inflammatory(M1) and anti-inflammatory(M2) actions, and M2 macrophages have four subtypes. The co-action of M1 and M2 subtypes can create a favorable microenvironment, releasing cytokines for damaged tissue repair. In this review, we discuss the activation of macrophages and their roles in severe peripheral nerve injury. We also describe the therapeutic potential of macrophages in nerve tissue engineering treatment and highlight approaches for enhancing M2 cell-mediated nerve repair and regeneration.  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