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   1545篇
  免费   90篇
  国内免费   6篇
耳鼻咽喉   13篇
儿科学   108篇
妇产科学   48篇
基础医学   211篇
口腔科学   49篇
临床医学   124篇
内科学   275篇
皮肤病学   53篇
神经病学   68篇
特种医学   53篇
外科学   118篇
综合类   25篇
一般理论   1篇
预防医学   138篇
眼科学   46篇
药学   204篇
中国医学   15篇
肿瘤学   92篇
  2023年   23篇
  2022年   42篇
  2021年   58篇
  2020年   21篇
  2019年   53篇
  2018年   70篇
  2017年   58篇
  2016年   58篇
  2015年   49篇
  2014年   84篇
  2013年   87篇
  2012年   165篇
  2011年   151篇
  2010年   76篇
  2009年   61篇
  2008年   88篇
  2007年   80篇
  2006年   80篇
  2005年   65篇
  2004年   47篇
  2003年   58篇
  2002年   43篇
  2001年   12篇
  2000年   6篇
  1999年   8篇
  1998年   5篇
  1997年   6篇
  1996年   6篇
  1995年   4篇
  1994年   4篇
  1992年   9篇
  1991年   6篇
  1990年   11篇
  1989年   3篇
  1988年   6篇
  1987年   3篇
  1986年   9篇
  1984年   2篇
  1983年   4篇
  1982年   1篇
  1981年   2篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
  1975年   2篇
  1973年   3篇
  1970年   1篇
  1969年   1篇
  1968年   2篇
  1967年   2篇
排序方式: 共有1641条查询结果,搜索用时 15 毫秒
991.
Data describing the use of recommended antihypertensive agents in the resistant hypertension population are limited. Treatment recommendations for resistant hypertension include maximizing diuretic therapy by using chlorthalidone and/or adding an aldosterone antagonist. Additional recommendations include combining antihypertensive agents from different drug classes. This retrospective cohort study describes antihypertensive use in patients with resistant hypertension defined as the concurrent use of ≥4 antihypertensive agents. Claims data from the Medstat MarketScan Commercial Claims and Encounter database were used to identify patients with resistant hypertension based on International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) diagnosis codes and National Drug Codes between May 1, 2008 and June 30, 2009. Of the 5 442 410 patients with hypertension in the database, 140 126 met study criteria. The most frequently prescribed antihypertensive classes were angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers (96.2%), diuretics (93.2%), calcium channel blockers (83.6%), and β-blockers (80.0%). Only 3.0% and 5.9% of patients were on chlorthalidone or an aldosterone antagonist, respectively. A total of 15.6% of patients were treated with angiotensin-converting enzyme inhibitor plus angiotensin receptor blocker. Our findings demonstrate that frequently prescribed antihypertensive agents for the treatment of resistant hypertension included guideline-recommended first-line agents. However, evidence-based and recommended agents, such as chlorthalidone and aldosterone antagonists, were underused. Moreover, minimally efficacious combinations, such as an angiotensin-converting enzyme inhibitor with an angiotensin receptor blocker, were prescribed at higher rates than evidence-based and recommended agents.  相似文献   
992.

Objective

The current review aims to synthesize existing knowledge about the relationship between psychological stress and wound healing.

Methods

A systematic search strategy was conducted using electronic databases to search for published articles up to the end of October 2007. The reference lists of retrieved articles were inspected for further studies and citation searches were conducted. In addition, a meta-analysis of a subset of studies was conducted to provide a quantitative estimation of the influence of stress on wound healing.

Results

Twenty-two papers met the inclusion criteria of the systematic review and a subsample of 11 was included in a meta-analysis. The studies assessed the impact of stress on the healing of a variety of wound types in different contexts, including acute and chronic clinical wounds, experimentally created punch biopsy and blister wounds, and minor damage to the skin caused by tape stripping. Seventeen studies in the systematic review reported that stress was associated with impaired healing or dysregulation of a biomarker related to wound healing. The relationship between stress and wound healing estimated by the meta-analysis was r=−0.42 (95% CI=−0.51 to −0.32) (P<.01).

Conclusion

Attention now needs to be directed towards investigating potential moderators of the relationship, mediating mechanisms underpinning the association, as well as the demonstration of a causal link by the development of experimental interventions in healthy populations.  相似文献   
993.
994.
The association of genetic factors and cerebral infarction (CI) has long been established. A positive family history alone is a recognized risk factor for CI and vascular events in general. However, there are certain inherited conditions that further increase the risk of stroke. These conditions are generally metabolic and mitochondrial genetic defects that have variable modes of inheritance. This article reviews major inherited metabolic disorders that predispose an individual to CI. Ten main conditions will be discussed: Fabry's disease, cerebrotendinous xanthomatosis, tangier disease, familial hypercholesterolemia, homocystinuria, methylmalonic acidemia, glutaric aciduria type I, propionic acidemia, ornithine transcarbamylase deficiency and mitochondrial encephalopathy, lactic acidosis and stroke-like phenomenon.  相似文献   
995.
Objective: The aim of this article is to present the assessment of the presentation of symptoms and psychiatric morbidity of children and adolescents from the Andaman and Nicobar islands during the first 3 months following the December 2004 earthquake and tsunami.Method: According to predefined criteria, a primary survivor is one who was exposed directly to the earthquake and tsunami, a secondary survivor is one with close family and personal ties to primary survivors, and tertiary survivors are individuals from the communities beyond the impact area, a majority of which were exposed to the earthquake only. This study included 37 primary and secondary survivors (aged 相似文献   
996.
We report an anatomical abnormality of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and ventral tegmental area (VTA) in different strains of inbred and outbred mice, one mouse strain (C57BL/6, B6) from different commercial suppliers, and in B6J mice bred internally. The abnormality consisted of a sporadic and unpredictable decrease in the number of dopaminergic neurons and/or a reduction or complete loss of tyrosine hydroxylase (TH) staining in a focal subset of neurons of the SNpc and/or VTA. This abnormality had a preference for a unilateral right side location, but could affect one or both sides of each subregion independently or together. The frequency and severity were variable between and within strains and colonies. The neuronal abnormality was found in mice from the five commercial suppliers examined, 5/15 inbred strains from a single supplier, and the one outbred strain (CD1) examined. The striatal content of catecholamines was not affected by this abnormality even when there was significant asymmetric TH neuronal loss, but did vary significantly between commercial suppliers. Manipulations in housing conditions did not affect the abnormalities. The mechanism and cause of this abnormality could not be determined in this study although several potential factors were eliminated. The frequent, but not universal, occurrence of this abnormality has significant implications for the use of laboratory mice in studying the midbrain dopamine system and warrants its recognition, knowledge of their frequency, and exploration of a mechanism to address or eliminate them.  相似文献   
997.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The natural population(s) of Gloriosa superba L. was mapped from 19 different locations of Western Himalayas,...  相似文献   
998.
Saliva and esophageal protection   总被引:3,自引:0,他引:3  
There has been much interest in recent years in the potential protective role of saliva in the esophagus. Variables such as salivary volume and neutralizing capacity have been studied both during basal conditions and in response to esophageal acid exposure, in healthy subjects and in patients with esophagitis. In addition to its known neutralizing capacity, saliva also contains growth factors. These polypeptides (of which epidermal growth factor has been studied most) have cytoprotective and healing properties in various segments of the gastrointestinal tract. Therefore, a deficiency in one or more of these growth factors might be a contributing factor in the development of gastroesophageal reflux disease (GERD) or its complication, such as Barrett's metaplasia. However, human studies have produced contradictory results regarding salivary growth factor deficiency in such patients. Current methods of investigation make it difficult to assess the importance of saliva in GERD. This may be due in part to the multifactorial nature of the disease and the difficulty in long-term, selective manipulation of salivary function in humans. Given the present data in the literature, it is therefore unknown if saliva plays an important role in esophageal protection.  相似文献   
999.
BACKGROUND: The developmental origins hypothesis suggests that pre- and postnatal exposures may influence vulnerability to later disease. The hypothalamic-pituitary-adrenal (HPA) axis is one pathway by which this may occur. Analyses were conducted in the Barry Caerphilly Growth (BCG) cohort to explore whether the postnatal exposure of childhood infections was related to HPA axis activity in adulthood. METHODS: Detailed data on type and frequency of illnesses were collected in the first 5 years of life. At the recent follow-up of this cohort (N=566; mean age of participants=25 years) three salivary cortisol samples were taken: two fasting samples in the morning (within 30 min of arrival at the study site and after venesection and cognitive test procedures) and one evening sample (2200 h). These data were transformed to provide AUCi and AUCg (indices reflecting axis reactivity and total hormonal output, respectively). FINDINGS: Negative associations were evident between number of upper respiratory illnesses and adult cortisol (as captured by the second morning sample, evening sample and AUCg). These relationships remained after controlling for other potential prenatal, postnatal and adult determinants. These associations were not observed for gastrointestinal illnesses suggesting that confounding by socioeconomic factors is unlikely to be the explanation. CONCLUSIONS: Childhood respiratory illnesses were associated with reduced HPA axis activity in adulthood. Further follow-ups will determine whether this pattern of activity influences vulnerability to diseases associated with HPA regulation.  相似文献   
1000.
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