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Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity, pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing the desirable therapeutic effect of radiotherapy.  相似文献   
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International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data...  相似文献   
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This study provides an expanded view of joint attention and its relation to expressive language development. A total of 144 toddlers (40 typically developing, 58 with autism spectrum disorder [ASD], 46 with developmental delay [DD]) participated at 24 and 31 months. Toddlers who screened positive for ASD risk, especially those subsequently diagnosed with ASD, had poorer joint attention skills, joint engagement during parent–toddler interaction, and expressive language. Findings highlight the dynamic relation between joint attention and language development. In the ASD and DD groups, joint engagement predicted later expressive vocabulary, significantly more than predictions based on joint attention skills. Joint engagement was most severely impacted when toddlers did not talk initially and improved markedly if they subsequently began to speak.  相似文献   
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OBJECTIVE: To determine whether there is an age-specific incidence of hospitalized cases of Shaken Baby Syndrome (SBS) that has similar properties to the previously reported "normal crying curve," as a form of indirect evidence that crying is an important stimulus for SBS. DESIGN AND SETTING: The study analyzed cases of Shaken Baby Syndrome by age at hospitalization from hospital discharge data for California hospitals from October 1996 through December 2000. PATIENTS: All cases of children less than 18 months (78 weeks) of age for whom the diagnostic code for Shaken Baby Syndrome (995.55) in the International Classification of Disease, Ninth Edition, Clinical Modification was assigned. RESULTS: There were 273 hospitalizations for SBS. Like the "normal crying curve," the curve of age-specific incidence starts at 2-3 weeks, has a clear peak, and declines to baseline by about 36 weeks of age. In contrast to the normal crying curve that peaks at 5-6 weeks, the peak of SBS hospitalizations occurs at 10-13 weeks. CONCLUSIONS: The age-specific incidence curve of hospitalized SBS cases has a similar starting point and shape to the previously reported normal crying curve but the peak occurs about 4-6 weeks later. Of the likely predisposing causes, this pattern is only consistent with the properties of early crying. There are numerous explanations for the lag in the peaks between crying and SBS hospitalizations, including the possibility of repeat shakings prior to hospitalization. The importance of crying as a stimulus to SBS may provide an opportunity for preventive intervention.  相似文献   
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Grit has been defined as passionate perseverance toward long-term challenging goals and it is associated with various positive outcomes for youth, including academic achievement. However, less is known about these associations for the two facets of grit (i.e., perseverance of effort, consistency of interest) and few studies have examined the link between grit and perceived social support. The present study examined the group-level demographic differences (i.e., gender, grade, socioeconomic status, and special education status) of grit in a high school sample (N = 1,077). In addition, direct associations between grit and perceived social support from multiple sources (i.e., teacher, classmate, parent) were examined, as well as a potential enhancing effect of social support as a moderator of the relation between grit and academic achievement. Results indicated positive associations among grit and its facets with social support from parents and classmates. Furthermore, the positive relation between grit and achievement was stronger for students reporting high social support from teachers, but not other sources (i.e., classmates, parents). Practical and theoretical implications for promoting student success are discussed.  相似文献   
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Acculturation consists of multiple domains (i.e., cultural practices, identifications, and values). However, less is known about how acculturation processes influence each other across multiple domains of acculturation. This study was designed to investigate transition patterns of acculturative processes within and across domains in a sample of 302 recent-immigrant Hispanic adolescents, Mage (SD) = 14.51 years (0.88) at baseline; male = 53%). Adolescents were assessed six times over a 3-year period. Latent profile analyses identified two profiles (high [or increasing] vs. low) for each domain at each timepoint. We found largely stable transition patterns in each domain over six timepoints. Importantly, sequential associations among profiles in acculturation domains were also detected. Implication for acculturation theory and research are discussed.  相似文献   
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