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The article investigates the ability of preschool children to “read” a photograph (lend it meaning) and to “write” it (to create digital photographs individually or in a group). The premise is that these literacy skills are mutually reinforcing and inseparable. The study uses a population of children aged three to four who attend a preschool that bases an entire program on digital photography for the purpose of encouraging multimodal literacy and the conscious integration of verbal and visual literacy. It is found that young children who study with and about digital photographs improve their ability to perceive details and broaden their linguistic parameters considerably, including vocabulary, use of complex sentences, asking questions, and telling stories about pictures. As for the acquisition of visual literacy skills, the findings show that this kind of learning encourages decision-making in choosing contents and designing photographs. It also encourages verbal reflection about self-taken pictures. The study demonstrates the need to apply an integrated approach to literacy and to make the requisite changes from early childhood on.  相似文献   
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We examined changes in suicide rates among 10–24-year-olds in the United States from 1992 to 2006. The overall suicide rate and the rate by firearms, poisoning, and other methods declined markedly, whereas the hanging/suffocation rate increased significantly from 1992 to 2006. This increase occurred across every major demographic subgroup, but was most dramatic for females.  相似文献   
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Analyses of administrative and large data sources in Sickle Cell Disease (SCD) can answer questions not suitable for prospective study but have been hampered by lack of validated methods to adjust for individual comorbidities and lack of baseline utilization data over time. We sought to develop a database to characterize inpatient SCD care across New York State and generate a re-weighted sickle-cell specific Charlson Comorbidity index (S-CCI) for use in future large data SCD research. We identified 18,541 individual SCD patients admitted to New York State hospitals between 2005 and 2013 from the SPARCS database. We present data from both a randomly selected derivation cohort, used to develop the S-CCI and a validation cohort, The S-CCI resulted in small improvements in model fit and discrimination while using fewer covariates, allowing a more parsimonious model. Despite being the most common comorbidity, chronic pulmonary disease was not predictive of mortality. Mortality per hospitalization was 0.61%. Many patients (32%) were admitted only once during the nine year period. However, the majority was admitted more frequently with over 15% of patients being admitted more than once per year.  相似文献   
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Longitudinal studies on patients for schizophrenia suggest that functional brain perturbations precede the onset of symptoms. Rats with a neonatal ventral hippocampal lesion (NVHL) are considered as a heuristic neurodevelopmental model of schizophrenia. We characterized basal metabolic changes observed in NVHL rats before and after the age when known behavioral alterations have been reported. Male pups were lesioned with ibotenic acid at postnatal day 7 (PD7). We measured local cerebral metabolic rates for glucose (LCMRglc) by the quantitative autoradiographic [14C]2‐deoxyglucose technique at pre‐ (PD21) and postpubertal (PD42) ages when NVHL rats do not express abnormal dopamine related behaviors, and at adulthood (PD70). We observed a widespread increase in LCMRglcs in PD21 NVHL indicative of an ongoing intense reorganization of the brain while at PD42, increases were less extended. At PD70, changes in glucose metabolism were restricted to specific systems, such as the auditory system, the cerebellum, the serotonergic median raphe, and median septum. These data show in a heuristic animal model of schizophrenia that functional metabolic changes within the brain could precede the onset of dopamine‐related behavioral alterations and lead to a distinct ensemble of functional changes in adulthood in systems that may be relevant to schizophrenia. © 2009 Wiley‐Liss, Inc.  相似文献   
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Hepatitis C virus RNA quantification results obtained in 18 laboratories using real-time PCR methods with 10 negative samples and 22 sample dilutions (viral loads of 0.5 to 500 IU/ml) showed a score of correct results of up to 93.5%. However, 55.6% of the laboratories did not follow the recommendations for the interpretation of their results, leading to ambiguous conclusions.  相似文献   
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This study examined the relationship between having a family history of affective disorder and neuropsychological functioning and PANSS symptoms in schizophrenia patients falling into four exclusive family history groups (affective spectrum disorders, schizophrenia spectrum disorders, both, or neither). Schizophrenia patients with a family history of affective illness had the best performance on IQ tests and executive function measures. Symptoms showed fewer family history group differences. Schizophrenia patients with a family history of affective disorder may be a distinct subtype in the group of schizophrenias and may be biologically more similar to patients with serious affective disorder.  相似文献   
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