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Anaemia is a serious and common problem among young children in sub-Saharan Africa. As a first step towards developing guidelines for its recognition and treatment, we conducted a study to evaluate the ability of health workers to use clinical findings to identify children with anaemia. Health care workers examined a total of 1104 children under 5 years of age at two hospital-based outpatient clinics in rural Malawi. Blood samples were taken to determine haemoglobin concentrations. Pallor of the conjunctiva, tongue, palm or nail beds was 66% sensitive and 68% specific in distinguishing children with moderate a anaemia (haemoglobin concentration, 5-8 g/dl) and 93% sensitive and 57% specific in distinguishing those with severe anaemia (haemoglobin concentration, < 5 g/dl). Even without laboratory support, which is often unavailable in rural Africa, clinical findings can identify the majority of children with anaemia.  相似文献   
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Today, a transition from traditional to modern marriages can be observed in many countries. This shift in patterns of marriage has evidently affected childbearing and reproductive practices. This study aimed to examine the relationship between patterns of marriage and reproductive practices in Iran. Hence, 880 married women, aged 15–49 years old, living in the North of Iran were selected using a multi-stage cluster sampling strategy and their patterns of marriage and reproductive practices were cross sectionally studied. The results revealed that there were no significant differences in the reproductive practices by three main patterns of marriage in Babol, Iran. The study also indicated that there were no significant differences in reproductive practices in three patterns of marriage after controlling for socio-economic variables. It seems that apart from the patterns of marriage, other influencing factors are the determinants of fertility in women, and the policy-makers of Iran need to pay attention to these determinants before making any decisions in this area.  相似文献   
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To determine the efficacy of oral vitamin D [25(OH)D] in patients with active rheumatoid arthritis (RA) who are in methotrexate (MTX) therapy, patients receiving stable doses of MTX were randomized to one of two dose groups and received 12?weeks of double-blind vitamin D[25(OH)D] (50,000?IU per week) or matching placebo. The moderate and major efficacy measure was the proportion of patients with >0.6 and >1.2 improvement in RA based on the Disease Activity Score 28(DAS 28) at 12?weeks. Safety measures included adverse events and laboratory assessments. On a background of MTX, the percentage of patients with a moderate/major DAS 28 response at week 12 in the vitamin D groups (76/44%) was not significantly different from placebo (64.6/33.4%). Adverse events were typically mild and included small hepatic enzyme elevation; we did not have any undesirable events resulting in discontinuation of study drug. In patients with active RA receiving stable doses of MTX, vitamin D showed non-significant improvement in efficacy outcomes compared to placebo.  相似文献   
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Purpose: The aim of this study is to compare the effect of smoking in corneal endothelial cell number and morphology by specular microscopy on a non-smoker population.

Methods: Our cross-sectional study was performed on 150 participants from a non-smoker population. Non-contact specular microscopy (Tomey Corporation Inc., Nagoya, Japan) was performed in the center of the cornea of all subjects. The cell density (CD), average cell size (AVG), percent of hexagonality (HEX%) and central corneal thickness (CCT) were calculated and compared in both groups.

Results: Totally, 76 eyes of 76 smokers and 74 eyes of 74 non-smokers were enrolled in the study from 2015 to 2016. The mean age of smokers and non-smokers were 48.61?±?17.04 and 46.39?±?13.02, respectively. The mean number of pack/year among the smokers was 17.36?±?14.68. Also, the mean values of AVG and CD were significantly different for these two groups (p?=?0.011 and p?=?0.039, respectively). Other corneal endothelial variables did not show a significant difference between smokers and non-smokers (p?>?0.05). However, smokers with severe nicotine dependency had significantly greater AVG and lower CD in comparison with the non-smokers (p?=?0.004 and p?=?0.013, respectively).

Conclusion: Our study showed that smoking can cause significant changes in some of the corneal endothelial variables, but not all of them.  相似文献   
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IntroductionChronic hyperglycemia activates the inflammatory pathways and oxidative stress mechanisms with consequent damage to nerve tissue and retina. The Keap1‐Nrf2 pathway acts as one of the most important antioxidant pathways of the organism. Variants of Keap1 could affect susceptibility to diabetes and its complications.MethodsIn a case‐control study, 400 individuals included type 2 diabetes mellitus (T2DM) patients without complication, with neuropathy, with retinopathy, and healthy individuals were investigated. The levels of glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA), and total antioxidant capacity (TAC) were measured using chemical methods. Using the PCR‐RFLP method, the Keap1 (rs11085735) variants were identified.ResultsNeuropathic patients had significantly lower levels of GSH, GPx, and TAC and higher levels of total oxidative status (TOS), MDA, and oxidative stress index (OSI) compared to T2DM patients without complication and controls. Lower levels of GSH and GPx and a higher level of MDA were observed in patients with retinopathy compared with controls. Obesity was associated with significantly lower GPx activity and higher TOS. A significantly higher Keap1 AA genotype was found in patients with neuropathy than T2DM without complication and controls. The presence of Keap1 AA genotype correlated with lower GPx activity compared to CC genotype.ConclusionsOur study suggests the role of reduced antioxidant system and Keap1 variants in the pathogenesis of T2DM and its complications of neuropathy and retinopathy and also obesity in enhanced oxidative stress. Monitoring oxidative stress parameters in diabetic patients, especially those with complication and their treatment with antioxidants is suggested.  相似文献   
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BACKGROUND: Reactive oxygen species generated in the skin by UV irradiation promote photoaging and photocarcinogenesis. The manganese (Mn) superoxide dismutase (SOD) is a primary antioxidant enzyme that crucially contributes to the homeostasis of oxygen radicals within the mitochondria, and thus critically participates in the control of senescence and tumor generation. OBJECTIVE: To determine whether repetitive UV-B exposure, as practiced for light hardening during phototherapy for various photodermatoses, can enhance the adaptive antioxidant response by up-regulating MnSOD activity in either the epidermal or the dermal skin compartment. DESIGN: In vitro experiments to determine MnSOD activity levels in cultured human dermal fibroblasts and epidermal cells (HaCaT cells and primary keratinocytes) at different times after direct UV-B exposure or after incubation of human dermal fibroblasts with supernatants from UV-B-irradiated epidermal cells. SETTING: Photobiological research laboratory in a university dermatology department. INTERVENTION: Irradiation of cultured human dermal fibroblasts and epidermal cells with UV-B. MAIN OUTCOME MEASURES: Manganese SOD messenger RNA and activity levels in cultured irradiated or mock-treated skin cells. RESULTS: No increase in MnSOD activity could be detected in fibroblasts or epidermal cells until 24 hours after UV-B irradiation. However, fibroblasts incubated with supernatants from UV-B-irradiated epidermal cells showed a marked increase in specific MnSOD messenger RNA and activity. Removal of interleukin 1alpha, interleukin 1beta, and tumor necrosis factor alpha from the supernatants led to a significant reduction of MnSOD mRNA in fibroblasts. CONCLUSION: Irradiation of the epidermal cells with UV-B induced a release of soluble factors that amplified MnSOD activity in fibroblasts via a paracrine mechanism.  相似文献   
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Cardiomyocyte apoptosis has been associated with the pathogenesis of heart failure as well as ischemic and inflammatory myocardial conditions. The aim of this study is to give a critical synopsis of cardiomyocyte apoptosis and identify methods to prevent or attenuate apoptosis in patients undergoing cardiac surgery. Clinical conditions and agents associated with decreased apoptotic index are early repair or replacement of valvular pathology before deterioration of ventricular function, afterload reduction with medication or intraaortic balloon pulsation in patients with acute increase in afterload or in hemodynamically compromised patients, decreasing catecholamine-induced cardiotoxicity by using β-blockers, phosphodiesterase inhibitors, or early insertion of intraaortic balloon pulsation or ventricular assist device. Prompt coronary revascularization, which reduces myocardial ischemia time, is the most effective antiapoptotic therapy. Reduction of myocardial apoptosis associated with cardiopulmonary bypass and aortic cross-clamping are other therapeutic targets. Some investigational therapies include ischemic preconditioning and use of antiapoptotic medication such as the caspase inhibitors, antioxidants, calcium-channel blockers, the insulin-like growth factor-1, and the poly-adenosine diphosphate-ribose-synthetase inhibitors. Most of the therapeutic implications in reducing cardiomyocyte apoptosis are still in the experimental phase. Some options are already incorporated in the clinical practice of the cardiovascular surgeon. New therapeutic considerations include avoiding sustained and long-term use of catecholamines and reducing or avoiding cardiopulmonary bypass—when clinically feasible. Noncatecholamine inotropes should be preferred for patients undergoing heart failure surgery and for patients with low output syndrome after open-heart surgery. The lessons learned from apoptosis research reinforce more liberal and early insertion of intraaortic balloon pulsation or ventricular assist device in clinical low output states.  相似文献   
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BACKGROUND: The n-3 fatty acid docosahexaenoic acid (DHA; 22:6n-3) is important for neural and visual functional development. In animals, 22:6n-3 deficiency is accompanied by increased docosapentaenoic acid (DPA; 22:5n-6), which suggests that the ratio of 22:6n-3 to 22:5n-6 could be a useful biochemical marker of low n-3 fatty acid status. The n-3 fatty acid status of preschool children has not been described, and data are lacking on whether low 22:6n-3 is accompanied by high 22:5n-6 in humans. OBJECTIVE: We determined n-3 fatty acid status and investigated the relation between 22:6n-3 and 22:5n-6 in children. DESIGN: In Canadian children aged 18-60 mo (n = 84), the n-3 and n-6 fatty acid status of erythrocyte phosphatidylethanolamine was measured, and dietary fat intake was estimated by using a food-frequency questionnaire. RESULTS: The mean (+/- SEM) 22:6n-3 concentration in erythrocyte phosphatidylethanolamine among children was 3.06 +/- 0.13 g/100 g fatty acids (5th-95th percentiles: 1.43-5.79 g/100 g fatty acids). Concentrations of 22:5n-6 increased with increasing 22:6n-3 concentrations in erythrocyte phosphatidylethanolamine (P < 0.01). Mean intakes of linoleic acid (18:2n-6), linolenic acid (18:3n-3), and trans fatty acids were 3.6 +/- 0.2%, 0.7 +/- 0.5%, and 2.0 +/- 1.3%, respectively. Phosphatidylethanolamine 22:6n-3 and 22:5n-3 concentrations were inversely related to the intakes of 18:2n-6 and trans fatty acids, but not to those of total fat or n-3 fatty acids. CONCLUSIONS: The concentration of 22:5n-6 is not a useful biochemical marker of low n-3 fatty acid intake or status in the membrane phosphatidylethanolamine of preschool children. High intakes of 18:2n-6 and trans fatty acids could compromise the incorporation of 22:6n-3 into membrane phospholipids.  相似文献   
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