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   124篇
  免费   11篇
耳鼻咽喉   1篇
基础医学   20篇
口腔科学   3篇
临床医学   13篇
内科学   30篇
皮肤病学   2篇
神经病学   6篇
外科学   23篇
预防医学   14篇
眼科学   8篇
药学   9篇
肿瘤学   6篇
  2023年   1篇
  2022年   1篇
  2021年   10篇
  2020年   4篇
  2019年   3篇
  2018年   8篇
  2017年   1篇
  2016年   1篇
  2015年   4篇
  2014年   7篇
  2013年   5篇
  2012年   9篇
  2011年   12篇
  2010年   7篇
  2009年   7篇
  2008年   10篇
  2007年   7篇
  2006年   7篇
  2005年   8篇
  2004年   3篇
  2003年   10篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   2篇
  1998年   1篇
  1997年   1篇
  1994年   1篇
排序方式: 共有135条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.

Background

Equine neonates have reduced humoral and cell-mediated immune responses compared to adult horses after administration of killed vaccines. As a basis for this study, we hypothesized that newborn foals can mount strong immune responses after vaccination with live Mycobacterium bovis BCG.

Methods

Healthy 4-day-old foals (n = 7), 4-month-old foals (n = 7) and adult horses (n = 6) were vaccinated once with live M. bovis BCG. Age-matched animals (n = 5 per group) were used as unvaccinated controls. Relative vaccine-specific immunoglobulin concentrations and whole blood mRNA expression of IFN-γ, IL-4, and IL-10 were measured prior to and 2, 4, 6, and 8 weeks after vaccination. Eight weeks after vaccination, delayed type hypersensitivity (DTH) responses were assessed by measuring the increase in double skin thickness after intradermal injection of purified protein derivative.

Results

Both groups of foals and adult horses responded with a significant increase in vaccine-specific total IgG, IgGa, IgGc, IgG(T), and IgM concentrations. In contrast, only adult horses mounted significant IgGb responses. Vaccine-specific concentrations of total IgG and IgGa were significantly higher in adult horses than in 4-day-old foals whereas IgGc responses were significantly higher in 4-day-old foals than in the other two age groups. Adult horses had significantly higher basal IFN-γ and IL-4 mRNA expression than both groups of foals but vaccination with M. bovis BCG did not significantly increase expression of these cytokines, regardless of age group. Immunized horses had significantly higher DTH responses than age-matched unvaccinated controls. DTH responses were significantly greater in both groups of vaccinated foals than in vaccinated adult horses.

Conclusion

Despite a naïve immune system, newborn foals have the ability to mount robust antibody and cell-mediated immune responses to M. bovis BCG.  相似文献   
5.
Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ER-α), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-α and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ER-α agonist. Studies employing ER-α–null or ER-β–null mice, ER-α loss-of-function mutant rats, or siRNA demonstrated that ER-α is necessary for E2 to upregulate RV apelin. E2 and ER-α increased BMPR2 in pulmonary hypertension RVs and in isolated RV cardiomyocytes, associated with ER-α binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to exert RV-protective effects. E2 or ER-α agonist rescued monocrotaline pulmonary hypertension and restored RV apelin and BMPR2. We identified what we believe to be a novel cardioprotective E2/ER-α/BMPR2/apelin axis in the RV. Harnessing this axis may lead to novel RV-targeted therapies for PAH patients of either sex.  相似文献   
6.
7.
Reduced heart rate variability (HRV) is a predictor of poor outcome in several pathologies and in general population. Whether HRV is altered during normal daily activities or influenced by anticholinergic and β-adrenergic medications in chronic obstructive pulmonary disease (COPD) remains unknown. Forty-one clinically stable COPD patients and 19 healthy controls matched for age, sex and smoking history underwent a 24-hour ambulatory ECG recording during normal daily activities. HRV was assessed by standardized temporal and spectral analysis. COPD patients showed a reduced HRV (LF/HF ratio) compared with healthy controls (median [interquartile range]) during daytime (2.6 [1.5-3.8] vs. 3.5 [2.9-5.6]), nighttime (1.8 [1.1-4.3] vs. 4.2 [2.7-6.9]) as well as during the entire 24-hour (1.9 [1.5-3.4] vs. 3.9 [3.2-5.6]) recordings (all P < 0.005). There was no significant difference between the two groups in the time domain and in the low frequency or high frequency domain for the 24-hour period analysis. In COPD patients, the 24-hour LF/HF ratio positively correlated with forced expiratory volume in 1 second (FEV(1)) (r = 0.342, P = 0.028) and negatively correlated with age (r = -0.317, P = 0.044). In multiple regression analysis, LF/HF ratio was associated with FEV(1) (P = 0.05) but not with age (P = 0.08). There was no difference of HRV between patients using or not anticholinergic or β-agonist medications. These results demonstrate that COPD patients have a reduced sympatho-vagal balance compared with healthy subjects. HRV correlates with disease severity and does not seem to be influenced by anticholinergic or adrenergic medications.  相似文献   
8.
9.

Purpose

The use of a ureteral access sheath (UAS) during flexible retrograde intrarenal surgery (RIRS) has become increasingly popular. Our aim was to evaluate the accessibility of a new UAS device, allowing the transformation of the working guidewire into a safety guidewire.

Methods

A prospective, multicenter study was conducted between January and February 2010 in six European tertiary reference centers. Patients needing flexible RIRS were eligible to participate in the study. In all cases, insertion of the Re-Trace? (12/14Fr, Coloplast, Denmark) was attempted at the beginning of the procedure. Insertion success was defined as placement of the UAS in the lumbar ureter with successful disengagement of the working guidewire, which turned into a safety guidewire. Influence of gender and pre-stenting status was analyzed by univariate analysis.

Results

137 UASs were used in 75 male and 62 female patients. 25.5 % of ureters were pre-stented: men were 2.17 more often pre-stented than women. The overall Re-Trace? insertion rate was 82.5 %. Success rate was not significantly different between men and women (77.3 vs. 88.7 %, respectively, p = 0.11). Pre-stenting status did not significantly influence the success rate (p = 0.31). When analyzing the combined influence of pre-stenting status and gender, the worst success rates seemed to be obtained in men without pre-stenting, but no significant differences were found between groups.

Conclusions

Re-Trace? UAS showed good overall insertion rates. This evaluation validated the new concept of guidewire disengagement: A single wire automatically switches from working to safety role.  相似文献   
10.
Small-fibre neuropathies (SFNs) can be defined as diseases of small nerve fibres. Because their symptoms are mainly located in the skin in the initial stages, dermatologists may frequently be confronted with these diseases. Moreover, skin biopsies and the subsequent measurement of intraepidermal nerve fibre density have become a widely accepted technique to investigate the structural integrity of small nerve fibres. The pathogenesis of injury to small nerve fibres is poorly understood. It probably depends on the cause. SCN9A-gene variants have been reported. Diabetes mellitus is one of the main causes of SFNs. Some causes of SFNs are very well-known to dermatologists: Gougerot-Sjögren syndrome, lupus, sarcoidosis and Fabry disease. We also discuss erythermalgia, prurigo nodularis, nummular eczema, burning mouth syndrome and sensitive skin as SFNs.  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