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   3247篇
  免费   203篇
  国内免费   40篇
耳鼻咽喉   11篇
儿科学   98篇
妇产科学   70篇
基础医学   455篇
口腔科学   34篇
临床医学   289篇
内科学   951篇
皮肤病学   63篇
神经病学   420篇
特种医学   64篇
外科学   253篇
综合类   6篇
预防医学   150篇
眼科学   60篇
药学   221篇
中国医学   4篇
肿瘤学   341篇
  2024年   10篇
  2023年   55篇
  2022年   121篇
  2021年   185篇
  2020年   119篇
  2019年   134篇
  2018年   141篇
  2017年   85篇
  2016年   115篇
  2015年   151篇
  2014年   153篇
  2013年   182篇
  2012年   300篇
  2011年   312篇
  2010年   170篇
  2009年   154篇
  2008年   217篇
  2007年   170篇
  2006年   173篇
  2005年   128篇
  2004年   121篇
  2003年   116篇
  2002年   92篇
  2001年   21篇
  2000年   8篇
  1999年   9篇
  1998年   14篇
  1997年   4篇
  1996年   6篇
  1995年   5篇
  1994年   2篇
  1993年   6篇
  1992年   2篇
  1989年   2篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1979年   1篇
  1978年   2篇
排序方式: 共有3490条查询结果,搜索用时 15 毫秒
41.
Despite the high prevalence of depressive disorders in cancer patients and elderly people, the topic of depression in elderly cancer patients still remains unexplored. This emerges from a systematic review of the literature conducted to investigate issues of depression, diagnosis, pathogenesis, treatment and their complex neuroimmunobiological interactions. Indeed, it becomes apparent that depression in elderly patients with cancer may have a peculiar phenomenology. In addition, the moderate rate of major depressive disorder and the high rate of minor depressive disorder are accompanied by subthreshold forms of depression that are at risk to be underrecognized and untreated. Immune dysfunction may represent a common pathogenic ground of depression, cancer and aging. This may have important implications for treatment. In the near future, we need to develop validated mood disorder diagnoses and verify antidepressant treatment efficacy for elderly cancer patients with depression in order to improve their clinical outcome and quality of life.  相似文献   
42.

Objective

To assess the prevalence and risk factors for endothelial dysfunction detected by peripheral artery tonometry in systemic lupus erythematosus patients with early disease without cardiovascular disease and risk factors.

Methods

All the consecutive adult lupus patients, with a disease duration <5 years, seen in our hospital from December 2014 to March 2016 were considered. We excluded patients with any history of cardiovascular disease or risk factors possibly affecting peripheral artery tonometry. Enrolled patients were matched for sex, age, body mass index, and blood pressure with healthy controls with the same exclusion criteria. Patients and controls received a transthoracic Doppler echocardiogram and an evaluation of endothelial function by peripheral artery tonometry.

Results

Twenty patients (100% female) with a median disease duration of 14 months (range 1–58 months), a mean ± SD age of 42 ± 15 years, and a mean ± SD age at diagnosis of 40 ± 16 years were enrolled and matched with 20 controls. Peripheral artery tonometry showed a significantly higher prevalence of endothelial dysfunction (P = 0.003) and vascular stiffness (P = 0.02), while echocardiography detected a significantly higher prevalence of left ventricular concentric remodeling (P = 0.003), grade I diastolic dysfunction (P = 0.047), and subclinical increase of filling pressures (P = 0.039) in lupus patients compared to controls. Among lupus patients, no features were associated with endothelial dysfunction.

Conclusion

A high rate of endothelial dysfunction and vascular stiffness occurs in early lupus patients without cardiovascular risk factors and disease. Larger studies are needed to confirm our results and to look for patients’ characteristics possibly associated with these abnormalities.
  相似文献   
43.
44.
45.
In recent years,a number of case reports and clinical studies have highlighted the risk of hepatitis B and C virus reactivation in patients with inflammatory bowel disease who are treated with immunosuppressive drugs.The cases of viral hepatitis reactivation that have been reported are characterized by a wide range of clinical manifestations,from viremia without clinically relevant manifestations to fulminant life-threatening hepatitis.The development and dissemination of biological immunosuppressive drugs have led to a significant increase in the number of reports of interest to physicians in a variety of clinical settings.On this topic,there have been a number of published guidelines and reviews that have collected the available evidence,providing recommendations on prophylactic and therapeutic strategies and methods for monitoring patients at risk.However,it should be noted that,to date,very few clinical studies have been published,and most of the recommendations have been borrowed from otherclinical settings.The published studies are mostly retrospective and are based on very heterogeneous populations,using different therapeutic and prophylactic regimens and obtaining conflicting results.Thus,it seems clear that it is desirable to concentrate our efforts on prospective studies,not conducting further reviews of the literature in the continued absence of new evidence.  相似文献   
46.
47.
No data are present in the literature about the effect of cytokines on the prototype β chemokine (C-C motif) ligand 2 (CCL2) or of peroxisome proliferator-activated receptor α (PPARα (PPARA)) activation on CCL2 and CXCL10 chemokines secretion in fibroblasts or preadipocytes in Graves' ophthalmopathy (GO). We have tested the effect of interferon γ (IFNγ (IFNG)) and tumor necrosis factor α (TNFα) on CCL2, and for comparison on the prototype α chemokine (C-X-C motif) ligand 10 (CXCL10), and the possible modulatory role of PPARα activation on secretion of these chemokines in normal and GO fibroblasts or preadipocytes in primary cell cultures. This study shows that IFNγ alone, or in combination with TNFα, stimulates the secretion of CCL2 in primary orbital fibroblasts or preadipocytes from patients with GO at levels similar to those observed in controls. IFNγ and TNFα also stimulated CXCL10 chemokine secretion as expected. The presence of PPARα and PPARγ (PPARG) in primary fibroblasts or preadipocytes of patients with GO has been confirmed. PPARα activators were able to inhibit the secretion of CXCL10 and CCL2, while PPARγ activators were confirmed to be able to inhibit CXCL10 but had no effect on CCL2. PPARα activators were stronger inhibitors of chemokine secretions than PPARγ agonists. In conclusion, CCL2 and CXCL10 are modulated by IFNγ and TNFα in GO. PPARα activators inhibit the secretion of the main prototype α (CXCL10) and β (CCL2) chemokines in GO fibroblasts or preadipocytes, suggesting that PPARα may be involved in the modulation of the immune response in GO.  相似文献   
48.
49.
ObjectiveThe objective was to evaluate the seasonal lipid variations in type 2 diabetic (DM2) outpatients.Materials/Methods302 (183 women and 119 men) DM2 subjects with or without statins therapy were screened. Body weight, HbA1c, total cholesterol (TC), high density lipoprotein (HDL-C), triglycerides (Trg) and low density lipoprotein cholesterol (LDL-C) were measured and patients’ data of diet and physical activity were recorded during fall/winter (F/W) and spring/summer (S/S) seasons.ResultsHbA1c levels showed seasonal variability without statistical significance. During the colder seasons we observed an increase (P<.05) of weight associated with higher calorie intake and reduced physical activity. We showed a peak of TC, LDL-C and Trg levels during F/W while HDL-C levels were reduced. Median TC levels in F/W with respect to S/S were 197 vs 185 mg/dL (P<.001) without statins therapy and 172 vs 161 mg/dL (P<.001) in patients under statins therapy. Median LDL-C levels, without or with statin therapy, were 122 vs 114 mg/dL (P<.001) and 97.5 vs 88.5 mg/dL (P<.001), respectively. This seasonal lipids changes from F/W to S/S, modulated the percent of patients at LDL-C target < 100 mg/dL, both without or under statins treatment: from 22% to 29.5% (P<.05) with odds ratio 0.73 (95% CI 0.62–0.87) and from 47% to 55% (P<.001) with odds ratio 0.68 (95% CI 0.58–0.76), respectively.ConclusionsDM2 patients showed a peak of TC and LDL-C during colder months associated with changes of diet and lifestyle habits. This seasonal lipid trend modified the percentage of patients at LDL-C therapeutical target.  相似文献   
50.
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