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51.
PURPOSE: Some researchers (F. R. Vellutino, F. M. Scanlon, & M. S. Tanzman, 1994) have argued that the different domains comprising language (e.g., phonology, semantics, and grammar) may influence reading development in a differential manner and at different developmental periods. The purpose of this study was to examine proposed causal relationships among different linguistic subsystems and different measures of reading achievement in a group of children with reading disabilities. METHODS: Participants were 279 students in 2nd to 3rd grade who met research criteria for reading disability. Of those students, 108 were girls and 171 were boys. In terms of heritage, 135 were African and 144 were Caucasian. Measures assessing pre-reading skills, word identification, reading comprehension, and general oral language skills were administered. RESULTS: Structural equation modeling analyses indicated receptive and expressive vocabulary knowledge was independently related to pre-reading skills. Additionally, expressive vocabulary knowledge and listening comprehension skills were found to be independently related to word identification abilities. CONCLUSION: Results are consistent with previous research indicating that oral language skills are related to reading achievement (e.g., A. Olofsson & J. Niedersoe, 1999; H. S. Scarborough, 1990). Results from this study suggest that receptive and expressive vocabulary knowledge influence pre-reading skills in differential ways. Further, results suggest that expressive vocabulary knowledge and listening comprehension skills facilitate word identification skills.  相似文献   
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1. In orefer to develop a simple, efficient system for the highlvel expression of dopamine recetors in eukaryotic cells, we have studied the effects of n-butyrate on the expression of rat D1A dopamine receptor cDNA in mouse fibroblast LTK- cells as compared with those of n-butyrate on endogenous D1 receptor levles in opossum kidney cells.
2. In the transfected LTK- cell mebranes with pRc/CMVD1A receptor cDNA, a selective D1 dopamine antagonist, [3H]-SCH 23390, exhibited a Kd of 0.9 ± 0.1 nmol/L and a Bmax of 0.35 ± 0.05 pmol/mg protien (n = 5).
3. Addtion of n-butrate (2–10 mmol/L) to the culture medium for 48h dose-dependently increased the D1A receptor level up to 1.5 ± 0.3 pmol/mg protien (n = 7), although the Kd values were not affected. The increase in receptor level was accompanined by an elevation of selective D1 agoinist-induced adenyly cyclase activity.
4. In contrast, n-butyrate treatment (2–10 mmol/L) did not affect either endogenous D1 receptor levels or fendoldopmainduced adenylyl cyclase activity in possum kidney cells.
5. These results sugges n-butyrate is a sueful tool for obtaining high-level expression of D1A dopamine receptor cDNA in mouse fibroblast LTK- cells.  相似文献   
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A case of an isolated, displaced fracture of the capitate is described. This rare carpal injury was treated by internal fixation with two Herbert screws. The fracture united and the patient achieved an excellent range of wrist motion. The Herbert screw is useful in the treatment of displaced fractures of the capitate since the screw maintains reduction, compresses the fracture site, and allows early wrist motion.  相似文献   
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This study examined ethical concerns related to exposing participants with childhood victimization histories to both trauma-specific and non-trauma-specific stimuli. We asked participants questions about childhood victimization experiences and exposed participants to a negatively-arousing experimental condition. Following each of these procedures and at a one-week follow-up session, participants completed a measure designed to asses their reactions to participation. The measure included several questions to assess reactions including questions about distress, benefit, and willingness to participate in the study again. Overall, participants reported low levels of distress and described their participation experience as interesting, enjoyable, and somewhat beneficial. Participants also indicated that they would be willing to participate in the study again with the knowledge of what participation was actually like. Participants with childhood trauma histories and PTSD symptoms reported more distress during the childhood maltreatment screening compared to other participants. However, the level of distress they experienced was mild and transitory. Our findings add to the emerging data indicating that individuals find their participation in trauma-related research to be a positive experience overall, rather than a harmful one.  相似文献   
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Abstract: Informal caregivers are the families and other unpaid caregivers in the home who support people of all ages with severe and chronic mental or physical disabilities. Home care of this sort has been increasing over the past 30 years because of the reduced number of beds in hospitals and nursing homes and increased outpatient and community care. Moreover, with an aging population and increasing rates of disability, the demand for family caregiving will continue to rise. This has important implications for the development of health, community service and social policy. At the same time, however, very little is known about the impact such changes are having on the caregivers of various ages and in various circumstances. The Victorian Health Promotion Foundation is funding a research and intervention program in Melbourne to promote wellbeing and prevent ill-health in caregivers.  相似文献   
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Transmetallation between commercially available solutions of gadolinium (Gd) chelates and the zinc (Zn)-dependent angiotensin-converting enzyme (ACE) was investigated. In vitro, the strongest inhibitions were observed for the linear Gd complexes, Gd diethylene-triamine pentaacetic acid (DTPA) bis-methylamide (BMA) (IC50 = .016 ± .006 mmol/1) and Gd-DTPA (IC50 = .350 ± .034 mmol/1). The two macrocycles Gd tetraazacyclododecane tetraacetic acid (DOTA) and Gd-HP-DO3A were similar and 400 times less active than Gd-DTPA-BMA. These effects were mainly due to the presence of free ligand for DTPA and calcium (Ca) chelate in the case of DTPA-BMA because the addition of Zn2+ in the same quantities suppresses their inhibitory effects. In vivo, these two solutions of linear Gd chelates significantly inhibited ACE activity (Gd-DTPA: 67 ± 9% versus baseline; and Gd-DTPA-BMA: 73 ± 2% versus baseline at the clinical dose of .1 mmol/kg), whereas no significant effect was observed for the two macrocyclic chelates Gd-DOTA and Gd-HP-DO3A. Formulating the Gd chelate solution with either an excess of free ligand or Ca chelate (to decrease Gd3+ release) in the case of linear Gd chelate may have deleterious biologic consequences.  相似文献   
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Eighteen pediatric cancer patients and their families participatedin a longitudinal study to assess the effects of a camp experienceon daily activity and family interactions. Based on maternalreport, changes were found in the amount of time these childrenspent in social, physical, and self-engaged activities. Mothersand a sibling closest in age to the patient also noted changesin their own frequency of activities spent with the family andwith others. These changes were evident when comparing measuresobtained 2 weeks prior to and 2 weeks after camp. Many changeswere still present 1 month after attending camp. These datasupport the use of a camp experience as an intervention to facilitatea return to more normal, healthy functioning by pediatric cancerpatients and their families.  相似文献   
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