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Schwann cells participate in myelin phagocytosis in the early stage of Wallerian degeneration, prior to the recruitment of macrophages. This is the first report that Schwann cells induce heme oxygenase-1 (HO-1), a 32-kDa heat shock protein, only when they have transformed into myelin-phagocytosing cells from myelinating cells (days 2-3) immediately after crush injury of rat sciatic nerves. Double immunofluorescent labelling for HO-1 and transferrin receptors revealed that HO-1-immunoreactive Schwann cells also expressed transferrin receptors suggesting activation of iron metabolism. The transient induction of HO-1 in Schwann cells may contribute to the adaptive function in an altered environment when the cells have lost contact with axons, and may play a crucial role in the ensuing regeneration.  相似文献   
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The water-soluble glucan was obtained from Pleurotus florida fruit bodies by hot water extraction, ethanol precipitation, DEAE cellulose dialysis and Sephadex G-75 gel filtration. The structural information of the glucan was achieved by chemical (hydrolysis, methylation, periodate oxidation) and spectroscopic (1H and 13C) analyses, indicated a repeating unit built up of (1→6)-linked D-glucose. The following structure has been determined for the repeating unit: →6)-α-D-Glcp-(1→ This fraction exhibited significant macrophage activity through the release of nitric oxide  相似文献   
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BACKGROUND: Population-based incidence rates of work-related burn injuries and associated risk factors specific to anatomic sites and degree of burn are not known. METHODS: Using a state-managed workers' compensation database, we estimated incidence rates of work-related burn injuries and identified high-risk occupations and associated exposures. RESULTS: The annual incidence rate of occupational burn was 26.4 per 10,000 workers, with the highest rate observed in the manufacturing sector for males and in the service sector for females. Welders, cooks, laborers, food service workers, and mechanics had higher incidence rates of burn injury compared with other occupations. Wrist and hand burns accounted for a majority of burn injuries, with females experiencing greater incidence of these distal upper extremity burns (8.9 in females and 6.7 in males per 10,000 workers, respectively). Third-degree burns (incidence rate, 1.3 per 10,000 workers) were also most frequently observed in the upper extremities compared with other anatomic sites. The majority of wrist and hand burns were caused by hot liquids/ objects, whereas the majority of eye burns were associated with chemical exposures. Younger cooks and food service workers were at greater risk of burn than older coworkers. CONCLUSION: Specific occupations are associated with degree of burn, anatomic site, and exposures. This information will be useful for targeted intervention among high-risk occupations and work groups.  相似文献   
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Mothers are often responsible for preparing nutritious foods in their households. However, the quality of mother's diets is often neglected, which may affect both mother's and child's nutrition. Because no single food contains all necessary nutrients, diversity in dietary sources is needed to ensure a quality diet. We aimed to study the association between mother's dietary diversity and stunting in children <2 years attending Dhaka Hospital of icddr,b, a diarrhoeal disease hospital in Dhaka, Bangladesh. A case–control study (n = 296) was conducted from November 2016 to February 2017. Data were collected from mothers of stunted children <2 years (length‐for‐age z score [LAZ] < ?2) as “cases” and nonstunted (LAZ ≥ ?1) children <2 years as “controls.” Mothers were asked to recall consumption of 10 defined food groups 24 hr prior to the interview as per Guidelines for Minimum Dietary Diversity for Women. Among the mothers of cases, 58% consumed <5 food groups during the last 24 hr, compared with 45% in control mothers (P = 0.03). Children whose mothers consumed <5 food groups were 1.7 times more likely to be stunted than children whose mothers consumed ≥5 food groups (P = 0.04). Intake of food groups such as pulses, dairy, eggs, and vitamin A rich fruit was higher in control mothers. Proportion of mother's illiteracy, short stature, monthly family income <BDT 11,480, absence of bank account, and poor sanitation was also found to be higher in stunted group. Further study particularly intervention or longitudinal study to see the causality of mother's dietary diversity with child stunting is recommended.  相似文献   
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In this study we examine the longitudinal effects of psychiatric and substance use disorders on employment, in an employed population. The sample included respondents to the National epidemiologic survey on alcohol related conditions (NESARC) who were employed at Wave 1 (N = 22,407). Bivariate and multivariable analyses were conducted examining the associations between 12-month and new onset 12-month psychiatric diagnoses at Wave 1 and employment status at Wave 2. Past year and new onset 12-month depression, 12-month bipolar, new onset 12-month drug abuse, and 12-month and new onset 12-month drug dependence were associated with a decreased odds of being employed at Wave 2. This study suggests that it would be beneficial for employers to support their employees in participating in mental health treatment. Additionally, understanding how psychiatric disorders influence employment over the life course might inform the development of preemptive interventions to treat mental health symptoms.  相似文献   
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In recent times engineered nanoparticles have been receiving much attention from researchers due to their extensive use in a variety of chemical, biological, and industrial areas. Their physiochemical properties have led to a number of uses in commercial products. Considering their broad applications, with increasing human contact the risks of exposure are also increasing. In vivo toxicity experiments involving administering nanoparticles to living organisms have shown their adverse effects on organ development and reproduction. Nanoparticles can be considerably more toxic than the large-sized particles since they can move relatively freely compared to bulkier molecules. Henceforth, it is our duty to assess the harmful health consequences associated with human exposure to nanoparticles in order to improve safe production and use. We will review the current applications of nanoparticles, and issues related to their toxicity. We will focus on safety regulations, risk assessment and regulatory guidelines of nanoparticles. The validation and standardization of nanotoxicity tests will further promote safe applications of nanotechnology in our daily lives.  相似文献   
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