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101.
IgE: an immunoglobulin specialized in antigen capture?   总被引:9,自引:0,他引:9  
IgE bound to the low-affinity receptor for immunoglobulin E (Fc epsilon R) on antigen-presenting cells (APCs) may permit binding of antigens to APCs prior to their processing and presentation. Here, G. C. Mudde and colleagues argue that the unique characteristics of IgE serological responses together with the distribution of Fc epsilon RII (CD23) on APCs are consistent with this novel function of IgE. The concept of IgE involvement in antigen capture is discussed in relation to Langerhans cells, B cells and follicular dendritic cells.  相似文献   
102.
103.
In congestive heart failure (CHF), the neurohormonal mechanisms that cause renal vasoconstriction, particularly those depending on the renin-angiotensin system, could interfere with renal vasodilating mechanisms. To elucidate this issue, we studied the kidney response to an amino acid infusion (known to cause renal vasodilation in healthy individuals) in eight patients with CHF. We found that the amino acid infusion (0.7 mL/kg/h of a 10% solution) elicited no renal hemodynamic response, in marked contrast to healthy subjects. We next hypothesized that the renin-angiotensin system (known to be activated in heart failure) has a role in the lack of response to the amino acid infusion. To test this hypothesis, we repeated the study after two 5-mg doses of enalapril, an inhibitor of the angiotensin-converting enzyme, administered 12 hours apart. After enalapril treatment, the amino acid infusion caused a 45% increase in mean renal blood flow (RBF) from 383 +/- 55 to 557 +/- 51 mL/min at the fifth hour (P < 0.05). This normalization of the renal response to the amino acid infusion occurred without changes in cardiac output or in systemic vascular resistance. Hence, the renal fraction of the cardiac output increased during the amino acid infusion. The recovery of the renal vascular response was not accompanied by an increase in glomerular filtration rate (GFR; filtration fraction decreased), suggesting a predominant efferent arteriole dilatation. Our study shows that, in heart failure, the kidney loses its ability to increase RBF in response to an amino acid load. This lack of renal vascular response can be restored by inhibiting the renin-angiotensin system and is unrelated to changes in systemic hemodynamics.  相似文献   
104.
Gheita  Tamer A  Sayed  Safaa  Azkalany  Gada S  Abaza  Nouran  Hammam  Nevin  Eissa  AH 《Clinical rheumatology》2018,37(3):757-763
Clinical Rheumatology - The objective of this study is to assess toll-like receptor-9 (TLR9) expression in CD3-positive T lymphocytes and CD19-positive B lymphocytes in systemic sclerosis (SSc)...  相似文献   
105.
106.

Background

This is the first work done on cryptosporidiosis among the children in Taiz, Yemen.

Methods

A number of 712 samples were collected from children of different ages (ranging from 1 month to 12 years) from Dec 2006 to Aug 2007. The collected samples were examined by Sheather''s sugar floatation and Modified Ziehl- Neelsen stain as well as ELISA methods. The test results were statistically analyzed by SPSS software.

Results

The overall positive percentage was 43.7%. The higher incidence (36.2%) was occurred in males while the lowest incidence (32.7%) was observed in females (r=0.876; P=0.001). The correlation between infected cases and the type of drinking water was r =0.121. Among the cases examined by ELISA (92 cases), 26.1% were infected. The correlation between seropositivity and gender was r=0.652 (P=0.031).

Conclusion

Cryptosporidium spp. is a significant pathogen among children at Taiz. Fresh water supplies, education, eating habits and domestic animals are considered the main sources for transmission of cryptosporidiosis.  相似文献   
107.
To develop effective interventions to stimulate physical activity (PA), insight into its underlying variables is needed. The aim of this study was to obtain an overview of the most relevant determinants of awareness, initiation and maintenance of PA among the over-fifties by means of a three-round Delphi study. In the first round, 17 key-experts outlined possible relevant determinants into an open-ended electronic questionnaire. In the second round, 118 experts completed a structured electronic questionnaire that was based on the first round results, in which they scored each determinant on its relevance. In the third round, experts were asked to re-rate the relevance of each determinant, after feedback was given about the group median relevance score. After three rounds, the experts agreed on 30 relevant determinants of the three phases of PA. When compared with longitudinal studies, the Delphi study pointed out new concepts, such as several post-motivational and social and environmental determinants as possible relevant determinants, suggesting that this method has the potential to trace new and promising determinants. The results further showed that next to similarities, much dissimilarity in relevant determinants of awareness, initiation and maintenance of PA was found, suggesting that most determinants could be phase specific.  相似文献   
108.
109.

Objective

This study examined the cost-effectiveness and cost-utility of two smoking cessation counseling interventions differing in their modality for patients diagnosed with coronary heart disease from a societal perspective.

Methods

In a randomized controlled trial conducted in Dutch hospital wards, cardiac patients who smoked prior to admission were allocated to usual care (n = 245), telephone counseling (n = 223) or face-to-face counseling (n = 157). The counseling interventions lasted for 3 months and were complemented by nicotine patches. Baseline histories were obtained, and interviews took place 6 months after hospitalization to assess self-reported smoking status and quality adjusted life years (QALYs). Incremental cost-effectiveness ratios per quitter and cost-utility ratios per QALY were calculated and presented in acceptability curves. Uncertainty was accounted for by sensitivity analysis.

Results

Using continued abstinence as the outcome measure showed that telephone counseling had the highest probability of being cost-effective. Face-to-to-face counseling was also more cost-effective than usual care. No significant improvements and differences in QALYs between the three conditions were found. Varying costs and effect estimations revealed that the results of the primary analyses were robust.

Conclusions

Assuming a willingness-to-pay of €20,000 per abstinent patient, telephone counseling would be a highly cost-effective smoking cessation intervention assisting cardiac patients to quit. However, the lack of consensus concerning the willingness-to-pay per quitter impedes drawing firm conclusions. Moreover, studies with extended follow-up periods are needed to capture late relapses and possible differences in QALYs.
  相似文献   
110.
Naevus comedonicus of the scalp   总被引:1,自引:0,他引:1  
We report the case of a 3-year-old boy with naevus comedonicus, characterized by confluent clusters of dilated follicular orifices plugged with keratinous material that resemble open comedones, located on the scalp.  相似文献   
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