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991.
The onset of crawling in infants contributes to cognitive, perceptual, social, and emotional development. Conversely, infants with motor impairment that delays or prevents autonomous mobility often have associated developmental delays. Evidence suggests that providing mobility may have positive developmental outcomes, however powered wheelchairs may not be recommended for very young children, due to safety concerns and the child’s level of cognitive maturity. The WeeBot is a mobility device controlled by infant weight shifting while seated; infants as young as 5 months have learned to use it. This study compares the efficacy of using the WeeBot vs. using the traditional manual joystick to control a robotic mobility device. Participants were 20 typically developing infants between 5 and 10 months who had not yet achieved independent mobility. A quasi-experimental two-group design was used: The first 10 participants recruited used the WeeBot (weight-shift); the next 10 used the joystick. Results showed that infants learned to use weight-shift control more easily and more skilfully than did infants using the joystick. The ability of infants to use the WeeBot suggests that an intuitive alternative control might allow very early powered mobility for children with disabilities, which might have implications for various aspects of their development.  相似文献   
992.
993.
Social media use by both teens and adults has become increasingly common. This frequency of interaction can be capitalized upon by researchers looking to design programs to limit youth substance use. This study serves as a first step in this area of research, examining how parent–child social media exchanges (specifically on Facebook) may be related to youth risk behavior. In a sample of 252 college students, results indicated that roughly 63% of youth reported being friends with their parents on Facebook while in high school. A minority (27%) reported they blocked their parents from seeing certain material on their Facebook page, and most youth reported their parents discussed information from their Facebook page with some regularity (65%). Logistic regression analyses indicated that, when accounting for demographics, parental solicitation, and parental control efforts, youth who were friends with their parents on Facebook and did not block any materials from them had a decreased likelihood of alcohol and/or marijuana use in high school relative to those who were not friends with their parents on Facebook or who blocked materials from their parents. These findings imply that efforts to encourage parent–child interactions via social media may help prevent substance use in high school.  相似文献   
994.
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.  相似文献   
995.
Nickel is the leading cause of allergic contact dermatitis (ACD) from early childhood through adolescence. Studies have shown that skin piercings and other nickel‐laden exposures can trigger the onset of nickel ACD in those who are susceptible. Nickel ACD causes a vast amount of cutaneous disease in children. Cases of nickel ACD in children have been reported in peer‐reviewed literature from 28 states. Common items that contain inciting nickel include jewelry, coins, zippers, belts, tools, toys, chair studs, cases for cell phones and tablets, and dental appliances. The diagnosis of nickel ACD has been routinely confirmed by patch testing in children older than 6 months suspected of ACD from nickel. Unlike in Europe, there are no mandatory restrictions legislated for nickel exposure in the United States. Denmark has demonstrated that regulation of the nickel content in metals can lower the risk of ACD and the associated health care–related costs that arise from excess nickel exposure. To further awareness, this article reviews the prominent role of nickel in pediatric skin disease in the United States. It discusses the need for a campaign by caretakers to reduce nickel‐related morbidity. Lastly, it promotes the model of European legislation as a successful intervention in the prevention of nickel ACD.  相似文献   
996.
Ficolins, a group of oligomeric lectins consisting of three isoforms (H‐, L‐ and M‐ficolin), contribute to innate immunity via activating the complement pathway and/or acting directly as opsonins against pathogens and apoptotic cells. Because apoptotic cells likely drive the development of systemic sclerosis (SSc) partly through innate immunity, we assessed the clinical association of serum H‐ficolin levels in SSc patients. Despite no difference in serum H‐ficolin levels between SSc and control subjects, SSc patients with decreased serum H‐ficolin levels tended to have a higher prevalence of interstitial lung disease (ILD). More importantly, serum H‐ficolin levels inversely correlated with ground‐glass opacity score on chest computed tomography in SSc‐ILD patients. Therefore, H‐ficolin‐related innate immunity may be involved in SSc‐ILD development.  相似文献   
997.
Prostaglandin (PG) E2 promotes tumor growth via interaction with its G protein-coupled receptors and activation of intracellular signaling. Tuberous sclerosis 2 (tuberin) is a tumor suppressor, which negatively regulates cell growth. Its phosphorylation results in its inactivation and targeted down- regulation, thus lifting the growth inhibition effects. This study investigated the expression and localization of tuberin in neoplastic and normal endometrium and the effect of PGE2 on phosphorylation of tuberin via the Akt pathway. Quantitative RT-PCR and Western blot analysis demonstrated reduced expression of tuberin in neoplastic tissue, compared with normal endometrial tissue. Tuberin expression was localized by immunohistochemistry to the glandular epithelial compartment in neoplastic and normal endometrium. We investigated the effect of PGE2 on phosphorylation of tuberin via the Akt pathway. Treatment of neoplastic and normal endometrium with 100 nm PGE2 enhanced phosphorylated tuberin immunoreactivity in the glandular epithelium. PGE2 also phosphorylated Akt and tuberin in Ishikawa endometrial adenocarcinoma cells, leading to a reduction in expression of total tuberin protein. Cotreatment of cells with wortmannin or LY294002 inhibited the PGE2-induced phosphorylation of Akt and tuberin. These data suggest that PGE2 signaling may promote endometrial tumorigenesis by inactivation of tuberin after its phosphorylation via the Akt signaling pathway.  相似文献   
998.
999.
Ethnographic assessment of worker lifestyle and motivation was paired with measurement of health, maximum oxygen uptake, anthropometry, and cold response to predict productivity in order to determine how well behavioral ratings and biological rankings of worker capacity predict actual productivity. The subjects were Chinese laborers hauling heavy loads on a cycle by human power during a Beijing winter. Worker productivity was measured as pay for unit of work done. This paper reports the ethnographic methods and results. Worker health was assessed through a physical examination including vital signs, echocardiogram (ECG), nutrition, hemoglobin, and hematocrit. Worker motivation was assessed during 10 weeks of participant observation, extensive interview, and a visit to the worker's household. Motivation was rated using a rank-order comparison of all 50 workers from lowest to highest. Other observational ratings (household assets, demands on worker, and health of household members) were completed at the time of the home visit using five-point scales. © 1995 Wiley-Liss, Inc.  相似文献   
1000.
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