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   12248篇
  免费   884篇
  国内免费   43篇
耳鼻咽喉   187篇
儿科学   284篇
妇产科学   236篇
基础医学   1781篇
口腔科学   1168篇
临床医学   994篇
内科学   2638篇
皮肤病学   348篇
神经病学   868篇
特种医学   356篇
外国民族医学   1篇
外科学   1429篇
综合类   67篇
一般理论   6篇
预防医学   1239篇
眼科学   201篇
药学   853篇
中国医学   77篇
肿瘤学   442篇
  2023年   106篇
  2022年   112篇
  2021年   369篇
  2020年   316篇
  2019年   428篇
  2018年   478篇
  2017年   342篇
  2016年   379篇
  2015年   395篇
  2014年   550篇
  2013年   678篇
  2012年   973篇
  2011年   1032篇
  2010年   589篇
  2009年   469篇
  2008年   685篇
  2007年   742篇
  2006年   587篇
  2005年   568篇
  2004年   465篇
  2003年   386篇
  2002年   366篇
  2001年   277篇
  2000年   277篇
  1999年   205篇
  1998年   68篇
  1997年   56篇
  1996年   54篇
  1995年   54篇
  1994年   48篇
  1993年   38篇
  1992年   88篇
  1991年   85篇
  1990年   89篇
  1989年   60篇
  1988年   63篇
  1987年   73篇
  1986年   60篇
  1985年   54篇
  1984年   57篇
  1983年   43篇
  1982年   36篇
  1979年   33篇
  1978年   28篇
  1973年   20篇
  1970年   23篇
  1969年   20篇
  1967年   25篇
  1966年   23篇
  1965年   21篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Clinical Oral Investigations - The objective of this systematic review and meta-analysis (SRM) was to answer the question whether the use of ultrasonic irrigation (UI) results in less postoperative...  相似文献   
2.
Background/Aim: The Glutathione S-transferases (GSTs) are important carcinogen-metabolizing enzymes. Polymorphisms involved in these enzymes can modulate the development and treatment of head and neck cancer. To investigate the association of GSTs polymorphisms with head and neck cancer and risk factors, clinical-pathological features, and survival time of the patients treated with chemotherapy and/or radiotherapy. Methods: The GST gene polymorphisms were evaluated in 197 cases and 514 controls by PCR-RFLP-Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Results: The GSTP-313 was associated with a decreased risk for HNSCC (p=0.050). The GSTP1 haplotype analysis revealed a higher frequency of the AC and AT haplotypes in the case group than in the control group (p=0.013 and p=0.019, respectively), and the opposite for G-C haplotype (p = 0.015). Yet, the different combinations between the genotypes were associated with an increased risk of cancer. The study showed no association between the polymorphisms and primary tumor site, clinical-pathological characteristics, treatment (chemotherapy and/or radiotherapy) and survival time of the patients. Conclusion: The GST polymorphisms combination showed an increased risk for carcinogenesis, and studies with larger casuistry can contribute to the clarification of the role in individual patient differences for the response to chemotherapy and/or radiotherapy and identify biomarkers of susceptibility.  相似文献   
3.
4.
5.
Flow diverters are new generation stents that have recently garnered a large amount of interest for use in treatment of intracranial aneurysms. Flow diverters reduce blood flow into the aneurysm, with redirection along the path of the parent vessel. Flow stagnation into the aneurysm and neck coverage with subsequent endothelialization are the important synergistic mechanisms by which the therapy acts. Several studies have examined the mechanisms by which flow diverters subsequently lead to aneurysm occlusion. This review aims to provide a general overview of the flow diverters and their mechanism of action and potential implications. ANN NEUROL 2019;85:793–800.  相似文献   
6.
7.
8.
9.
The ability of mothers to sensitively attune their maternal responses to the needs of their developing young is fundamental to a healthy mother‐young relationship. The biological mechanisms that govern how mothers adjust caregiving to the dynamic changes in the demands of the young remain an open question. In the present study, we examined whether changes in monoamine levels, within discrete mesocorticolimbic structures involved in cognitive and motivational processes key to parenting, modulate this flexibility in caregiving across the postpartum period. The present study used a Wistar‐Kyoto (WKY) animal model of depression and control Sprague‐Dawley (SD) rats, which differ dramatically in their cognitive, motivational, and parenting performance. Levels of the monoamine neurotransmitters, dopamine, noradrenaline and serotonin, as well as their major metabolites, were measured within the medial prefrontal cortex, striatum, nucleus accumbens and medial preoptic area of SD and WKY mothers at early (postpartum day [PPD]7‐8), late (PPD15‐16) and weaning (PPD25) postpartum stages using high‐performance liquid chromatography with electrochemical detection. Consistent with our prior work, we find that caregiving of SD mothers declined as the postpartum period progressed. Relative to nulliparous females, early postpartum mothers had lower intracellular concentrations of monoamines, as well as lower noradrenaline turnover, and an elevated serotonin turnover within most structures. Postpartum behavioural trajectories subsequently corresponded to a progressive increase in all three monoamine levels within multiple structures. Compared to SD mothers, WKY mothers were inconsistent and disorganised in caring for their offspring and exhibit profound deficits in maternal behaviour. Additionally, WKY mothers had generally lower levels of all three monoamines, as well as different patterns of change across the postpartum period, compared to SD mothers, suggesting dysfunctional central monoamine pathways in WKY mothers as they transition and experience motherhood. Taken together, the results of the present study suggest a role for monoamines at multiple mesocorticolimbic structures with repect to modulating caregiving behaviours attuned to the changing needs of the young.  相似文献   
10.

Objectives

To analyze the factors associated with fatigue focusing on comorbidities in a large cohort of rheumatoid arthritis (RA).

Methods

Cross-sectional analyses were performed on RA patients from the French COMEDRA cohort study, a nurse-led program for comorbidities management. Fatigue was assessed using Question 3 of the Rheumatoid Arthritis Impact of Disease (RAID) score on a 0–10 numerical rating scale (NRS). Fatigue was defined as acceptable if?≤?2, moderate if 3 or 4, or severe if?≥?5 out of 10. Using univariate and multivariate models, the relationship between fatigue and demographics, social, disease characteristics, comorbidities (cardiovascular, infections, cancer, pulmonary, osteoporosis, and psychiatric disorders), physical activity, quality of life, and treatments was investigated.

Results

In total, 962 patients were analyzed. The mean fatigue score was 3.8?±?2.7, 40% of patients reported severe fatigue. Patients had an average of 1.8 additional morbid conditions, with anxiety/depression the most common (52%). In univariate analysis, severe fatigue was more frequent in women, in patients not working, and in those with less physical activity. It was associated with disease duration and activity, mHAQ, pain, sleeping and emotional difficulties. Severe fatigue correlated with Multimorbidity index assessing the number of morbid conditions and was associated with obesity, hypertension, COPD, and anxiety/depression. In multivariate models, the risk of severe fatigue was associated with female gender, disease activity, mHAQ, current treatment with NSAIDs and biologics, multimorbidity, obesity and anxiety/depression.

Conclusions

Assessment of comorbidities, psychological health and physical activity should be taken into account in order to address frequent RA-related severe fatigue.  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