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51.
Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.  相似文献   
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Sociodemographic, living standard measure, consumption of vegetables and fruit, and dietary diversity in relation to household food security were assessed. Using a hunger score, households were categorized as food secure (n = 125) or food insecure (n = 273). Food secure respondents had a higher mean dietary diversity score (3.98; 95%CI [3.79, 4.18] versus 3.65; 95% [CI 3.53, 3.77]), were more likely to eat vitamin A–rich foods (OR 1.15; 95% CI [1.05, 1.26]), a more varied diet (DDS ≥ 4, OR 1.90; 95% CI [1.19, 3.13]), and vegetables daily (OR 3.37; 95% CI [2.00, 5.76]). Cost limited daily vegetable/fruit consumption in food insecure households. Respondents with ≥ 8 years of schooling were more likely (OR 2.07; 95% CI [1.22, 3.53]) and households receiving social grants were less likely (OR 0.37; 95% CI [0.19, 0.72]) to be food secure. Results highlight the association between dietary diversity and household food security.  相似文献   
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A protein S deficient family presenting a variant protein S molecule in plasma and platelets is described. The propositus, age 20, and two brothers suffered from venous thrombotic disease. The propositus, the only family member studied while taking oral anticoagulants, had a protein S antigen (ag) level of 17% and undetectable activity. As demonstrated by immunoblotting both the propositus and one clinically affected brother (42% ag, 7% activity) presented variant protein S molecules of 65,000 molecular weight (mol wt) while the other clinically affected brother (64% ag, 11% activity) had only protein S with normal electrophoretic mobility of 70,000 mol wt. The mother had normal protein S levels (93% ag, 100% activity) but had both normal and variant protein S molecules and based on her functional protein S data a normal anticoagulant activity of the variant molecule is suggested. One asymptomatic but protein S deficient sister (68% ag, 9% activity) as well as the asymptomatic protein S deficient father (59% ag, 10% activity) had only protein S molecules of 70,000 mol wt. The variant protein S bound to C4b-binding protein in plasma, and differed from normal protein S in carbohydrate content. Platelets of each family member contained the same immunoblotting pattern of normal and variant protein S forms as found in plasma, consistent with the hypothesis that protein S gene expression involves codominant expression of two alleles that is similar in cells that control the synthesis of both platelet and plasma forms of protein S.  相似文献   
56.
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.  相似文献   
57.
Summary The absorption of monocomponent porcine125I-insulin Monotard and Isophane was studied in six insulin dependent diabetic patients over a period of 12 days. The absorption of insulin was measured as the disappearance of radioactivity from sites of injection. The daily125I-insulin doses ranged from 20 to 48 IU between patients. The insulin absorbed varied considerably within and between patients. The range of individual daily absorbed insulin varied from 19 to 104 per cent of the125I-insulin dose. A significant correlation (p<0.05) was found between insulin absorption and blood glucose concentration. Insulin absorption rates were relatively high before all hypoglycaemic episodes and reactive hyperglycaemia was only observed when relatively low insulin absorption rates followed the hypoglycaemic attack. The results show that lability in some insulin dependent diabetics is explained by variation in insulin absorption.  相似文献   
58.
Percutaneous balloon valvuloplasty has been shown to increase the aortic orifice area and to improve clinical symptoms. However, there are only few data concerning long-term results after balloon valvuloplasty. In this study, 36 patients (11 men, 25 women, mean age 75 +/- 8 years) were followed after balloon valvuloplasty for a period of up to 18 months by means of clinical parameters and repeated Doppler echocardiographic measurements after 1, 3, 6, 12 and 18 months. Invasive measurements revealed a decrease of the systolic peak gradient from 78 +/- 24 to 38 +/- 13 mm Hg (p less than 0.001), and an increase in the aortic orifice area from 0.58 +/- 0.23 to 0.93 +/- 0.2 cm2 (p less than 0.001). The Doppler echocardiographic approach revealed that the maximal instantaneous gradient decreased from 96 +/- 26 to 67 +/- 22 mm Hg (p less than 0.001). The aortic orifice area increased from 0.49 +/- 0.16 to 0.73 +/- 0.21 cm2 (p less than 0.001). Three patients (8%) died in the hospital. After hospital discharge, 16 patients (44%) died and 8 patients (22%) underwent successful aortic valve replacement after a mean follow-up of 8 +/- 6 months. Nine patients (25%) were alive after a follow-up period of 18 months. Seven of these (19%) remained clinically improved. During follow-up, the Doppler echocardiographic results revealed a continuous trend toward the preprocedural severity of the aortic valve stenosis. Progression of restenosis assessed by Doppler echocardiographic measurements was accelerated in the group of patients who subsequently died or underwent repeat balloon valvuloplasty or aortic valve replacement.  相似文献   
59.
Recent developments of optogenetic tools and fluorescence-based calcium recording techniques enable the manipulation and monitoring of neural circuits on a cellular level. Non-invasive imaging of brain networks, however, requires the application of methods such as blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), which is commonly used for functional neuroimaging. While BOLD fMRI provides brain-wide non-invasive reading of the hemodynamic response, it is only an indirect measure of neural activity. Direct observation of neural responses requires electrophysiological or optical methods. The latter can be combined with optogenetic control of neuronal circuits and are MRI compatible. Yet, simultaneous optical recordings are still limited to fiber-optic-based approaches. Here, we review the integration of optical recordings and optogenetic manipulation into fMRI experiments. As a practical example, we describe how BOLD fMRI in a 9.4-T small animal MR scanner can be combined with in vivo fiber-optic calcium recordings and optogenetic control in a multimodal setup. We present simultaneous BOLD fMRI and calcium recordings under optogenetic control in rat. We outline details about MR coil configuration, choice, and usage of opsins and chemically and genetically encoded calcium sensors, fiber implantation, appropriate light power for stimulation, and calcium signal detection, to provide a glimpse into challenges and opportunities of this multimodal molecular neuroimaging approach.  相似文献   
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