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   212篇
  免费   5篇
儿科学   14篇
基础医学   16篇
临床医学   12篇
内科学   67篇
皮肤病学   1篇
神经病学   8篇
特种医学   8篇
外科学   24篇
综合类   10篇
预防医学   50篇
药学   5篇
中国医学   2篇
  2023年   1篇
  2022年   3篇
  2021年   6篇
  2020年   8篇
  2019年   21篇
  2018年   13篇
  2017年   7篇
  2016年   12篇
  2015年   5篇
  2014年   15篇
  2013年   16篇
  2012年   11篇
  2011年   19篇
  2010年   13篇
  2009年   10篇
  2008年   16篇
  2007年   18篇
  2006年   2篇
  2005年   3篇
  2004年   7篇
  2003年   4篇
  2001年   2篇
  2000年   2篇
  1997年   1篇
  1985年   1篇
  1981年   1篇
排序方式: 共有217条查询结果,搜索用时 15 毫秒
21.
Systemic lupus erythematosus (SLE) is associated with severe and premature cardiovascular disease, which cannot be explained by traditional risk factors alone. This study aims to investigate novel cardiovascular risk factors and cardiac event predictors in inactive SLE female patients who do not have any major cardiovascular risk factors. Twenty-five inactive (SLE disease activity index score <4) SLE female patients and 22 healthy control women were studied. SLE patients with a history of diabetes mellitus, hypertension, hyperlipidemia, smoking, or coronary artery disease (CAD) were excluded. Venous blood samples were analyzed for lipid subfractions and novel cardiovascular risk factors such as lipoprotein (a), homocysteine, fibrinogen, high-sensitivity C-reactive protein (hs-CRP), and serum amyloid A (SAA) levels. Endothelial dysfunction was assessed by flow-mediated dilatation (FMD) from the brachial artery at baseline and during reactive hyperemia. SLE patients and controls were similar in terms of age (40±10 years vs 38±10 years, p = NS). No significant difference was found between the groups regarding family history of premature CAD, blood pressure, body mass index, lipoprotein (a), homocysteine, fibrinogen, SAA, apoprotein A-1 and B levels. Compared with the controls, SLE patients had higher levels of hs-CRP [median (range): 1.82 (0.02–0.98) vs 0.68 (0.02–0.35), p=0.04]. FMD was lower in SLE patients than controls (7.1±2.1 vs 11.4±1.2%, p<0.001). Increased levels of hs-CRP and decreased FMD were found in inactive SLE patients. Increased hs-CRP levels may reflect ongoing low-grade inflammation that could be a cause of impaired FMD in SLE patients. These findings suggest that SLE patients without traditional major cardiovascular risk factors may have increased risk of cardiovascular disease and future cardiac events.  相似文献   
22.
23.
BACKGROUND: The risk of atherosclerosis and its complications differs between male and female subjects. This is probably associated with gender differences in endothelial function as reflected by endothelium-dependent vasodilation. The aim of the study was to compare flow-mediated dilatation (FMD) in males and females with coronary artery disease (CAD), and to determine factors that might potentially influence FMD. METHODS: Ninety-six patients with stable CAD (CCS II-III): 76 males (mean age: 57.7 +/- 10 years) and 20 postmenopausal females (mean age: 60.1 +/- 10 years) were included into the study. Clinical data, pharmacotherapy, concomitant diseases, and FMD were all assessed. FMD was measured with high-resolution ultrasound as the percent change of brachial artery diameter (BAd) after a 3-minute occlusion (%FMD), and following the administration of 0.4 mg sublingual nitroglycerin (%NTG-MD). RESULTS: The percentage of FMD was significantly decreased (P < 0.05), and BAd was significantly larger (P < 0.001) in males as compared to females. Clinical data, pharmacotherapy, and concomitant diseases were comparable in the study groups.In all subjects examined, %FMD was related to BAd (r =-0.415, P < 0.001) and the percentage of ejection fraction (EF%) (r = 0.325, P < 0.01) in the univariate analysis, and to BAd only (r =-0.343, P < 0.01) in the multivariate analysis. The percentage of nitroglycerine-mediated vasodilatation (NTG-MD) correlated negatively with BAd (r =-0.430, P < 0.001), and positively with EF% (r = 0.334, P < 0.01) in the univariate analysis, and with BAd (r =-0.288, P < 0.05) in the multivariate analysis. Index %FMD x BAd was comparable for male and female subjects. CONCLUSIONS: Males and postmenopausal females with CAD show differences in endothelium-dependent vasodilatation that seem to secondarily result from differences in the BAd. Objective comparison of %FMD is only possible between patients with the same brachial artery size.  相似文献   
24.
目的探讨原发性扩张型心肌病(DCM)患者血管内皮功能状况,以及阿托伐他汀对内皮功能状况的影响。方法67例DCM患者随机给予或不给阿托伐他汀治疗8周后,观察血浆血管性假血友病因子(vwF),肱动脉内径扩张度(FMD)水平的改变。35例健康体检者作为正常对照组。结果两组DCM患者基础vWF水平高于健康对照组(P〈0.01),FMD水平低于正常对照组(P〈0.01);经过治疗后,阿托伐他汀组比非阿托伐他汀组vwF值降低更明显(P〈0.05),FMD值升高但无显著性差异。结论DCM患者存在内皮功能失调,阿托伐他汀能够改善DCM病人内皮功能紊乱。  相似文献   
25.
Foot-and-mouth disease (FMD) is endemic to sub-Saharan Africa. To further understand its complex epidemiology, which involves multiple virus serotypes and host species, we characterized the viruses recovered from FMD outbreaks in Ethiopia during 1981–2007. We detected 5 of the 7 FMDV serotypes (O, A, C, Southern African Territories [SAT] 1, and SAT 2). Serotype O predominated, followed by serotype A; type C was not recognized after 1983. Phylogenetic analysis of virus protein 1 sequences indicated emergence of a new topotype within serotype O, East Africa 4. In 2007, serotype SAT 1 was detected in Ethiopia and formed a new distinct topotype (IX), and serotype SAT 2 reappeared after an apparent gap of 16 years. The diversity of viruses highlights the role of this region as a reservoir for FMD virus, and their continuing emergence in Ethiopia will greatly affect spread and consequent control strategy of the disease on this continent.  相似文献   
26.
Objectives. This study sought to examine the effects of long-term estrogen therapy on vascular function in male to female transsexuals and to compare the findings with those observed in men and premenopausal women.

Background. Gender differences in coronary artery disease have largely been attributed to the beneficial effects of estrogen on vascular function and plasma lipids in women. However, the effects of estrogen on the male vasculature have not been widely studied.

Methods. We compared the effects of estrogen on vascular function in 14 male to female transsexuals, 14 age-matched men and 15 premenopausal women. Flow-mediated vasodilation and response to nitroglycerin were assessed in the brachial artery using noninvasive ultrasound.

Results. Flow-mediated vasodilation was similar in transsexuals and women but greater than that in men ([mean ± SE] 11.5 ± 1.3% and 9.4 ± 1.1% vs. 5.2 ± 1.0% respectively, p < 0.005). Responses to nitroglycerin were also greater in transsexuals and women than in men (21.6 ± 1.7% and 21.0 ± 0.9% vs. 14.5 ± 1.2%, respectively, p = 0.0005). These differences persisted even after adjusting for vessel size. Despite similar total cholesterol levels, transsexuals had high density lipoprotein cholesterol levels similar to those in women and greater than those observed in men (1.76 ± 0.12 and 1.82 ± 0.11 mmol/liter vs. 1.35 ± 0.07 mmol/liter, respectively, p < 0.005). Moreover, triglyceride levels were greater in transsexuals than in men and women, and low density lipoprotein cholesterol (LDL-C) particle size was smaller (25.7 ± 0.2 nm vs. 26.2 ± 0.1 and 26.6 ± 0.1 nm, respectively, p = 0.0001). Serum testosterone (an index of estrogen therapy in transsexuals) was markedly suppressed in transsexuals and similar to that in women. Univariate analysis revealed that there was a strong inverse correlation between serum testosterone and flow-mediated vasodilation (rs = −0.48, p < 0.005). Multivariate analysis revealed that the best combination of predictors of flow-mediated vasodilation was serum testosterone, vessel size and LDL-C (R2 = 0.3, p < 0.005).

Conclusions. Long-term estrogen therapy appears to improve vascular function in male to female transsexuals and occurs despite higher triglyceride levels and the presence of small, dense LDL-C. The beneficial effects of estrogen are not gender specific or solely mediated through endothelium-derived nitric oxide.

(J Am Coll Cardiol 1997;29:1437–44)  相似文献   

27.
Vascular endothelial function is declines with aging and is associated with an increased risk of cardiovascular disease. Lifestyle modification, particularly aerobic exercise and dietary adjustment, has a favorable effect on vascular aging. Curcumin is a major component of turmeric with known anti-inflammatory and anti-oxidative effects. We investigated the effects of curcumin ingestion and aerobic exercise training on flow-mediated dilation as an indicator endothelial function in postmenopausal women. A total of 32 postmenopausal women were assigned to 3 groups: control, exercise, and curcumin groups. The curcumin group ingested curcumin orally for 8 weeks. The exercise group underwent moderate aerobic exercise training for 8 weeks. Before and after each intervention, flow-mediated dilation was measured. No difference in baseline flow-mediated dilation or other key dependent variables were detected among the groups. Flow-mediated dilation increased significantly and equally in the curcumin and exercise groups, whereas no changes were observed in the control group. Our results indicated that curcumin ingestion and aerobic exercise training can increase flow-mediated dilation in postmenopausal women, suggesting that both can potentially improve the age-related decline in endothelial function.  相似文献   
28.

Aim of the work

To evaluate platelet indices in systemic sclerosis (SSc) patients and identify their clinical significance as novel inflammatory biomarkers in correlation to markers of endothelial dysfunction: vascular endothelial growth factor (VEGF) and flow mediated dilatation (FMD).

Patients and methods

Thirty-five SSc patients were enrolled in addition to 35 age and sex matched healthy volunteers as controls. All patients and controls underwent full medical history taking, thorough clinical examination, assessment of severity extent of skin sclerosis using the modified Rodnan skin score (mRss), erythrocyte sedimentation rate (ESR), C- reactive protein (CRP), complete blood count with special consideration to mean platelet volume (MPV), platelet distribution width and platelets count, assay for serum VEGF concentration, and brachial FMD assessment by color duplex sonography.

Results

There was a highly significant decrease in the mean MPV in SSc patients compared to the controls (8.65?±?0.6?fl vs. 9.55?±?0.52?fl). There was a significant increase in the mean platelet count in SSc patients compared to controls (331.63?±?64.66?×?103/ml vs. 297.80?±?44.48?×?103/ml). In SSc patients, a significant negative correlation was found between the mean MPV and each of ESR, CRP and VEGF (r?=??0.42, r?=??0.37 and r?=??0.55 respectively, p?<?.05); and a significant positive correlation was found between the mean MPV and mean FMD (r?=?0.38, p?<?.05). Linear regression test, showed an association between mean MPV and each of ESR and CRP (t?=??3.31, ?2.92 respectively, p?<?.05).

Conclusion

MPV levels could be an easily measurable parameter to reflect the inflammatory condition in systemic sclerosis patients.  相似文献   
29.
In 1898, foot‐and‐mouth disease (FMD) earned a place in history as the first disease of animals shown to be caused by a virus. Yet, despite over a century of active investigation and elucidation of many aspects of FMD pathogenesis, critical knowledge about the virus–host interactions is still lacking. The aim of this review is to provide a comprehensive overview of FMD pathogenesis in cattle spanning from the earliest studies to recently acquired insights emphasizing works which describe animals infected by methodologies most closely resembling natural infection (predominantly aerosol or direct/indirect contact). The three basic phases of FMD pathogenesis in vivo will be dissected and characterized as: (i) pre‐viraemia characterized by infection and replication at the primary replication site(s), (ii) sustained viraemia with generalization and vesiculation at secondary infection sites and (iii) post‐viraemia/convalescence including resolution of clinical disease that may result in long‐term persistent infection. Critical evaluation of the current status of understanding will be used to identify knowledge gaps to guide future research efforts.  相似文献   
30.
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