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BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference.  相似文献   
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Objective

To document perceived adherence to treatment (taking medications and performing exercises) in patients with juvenile idiopathic arthritis (JIA) over a 1‐year period and to identify related factors.

Methods

We surveyed parents of patients with JIA at the Montreal Children's Hospital and British Columbia's Children's Hospital in Vancouver. Parents were asked to respond to a series of questionnaires every 3 months over a 12‐month period. Perceived adherence was evaluated on a 100‐mm visual analog scale (VAS) in the Parent Adherence Report Questionnaire (PARQ). Parental coping, distress, child function, disease severity and duration, perceived helpfulness of treatment, problems encountered, and sociodemographic data were also assessed.

Results

The mean age of our sample of 175 children was 10.2 years; mean age at diagnosis was 6.1 years and mean disease duration was 4.1 years. Perceived adherence to medications was consistently high, with average adherence at baseline, 3, 6, 9, and 12 months being 86.1, 91.7, 90.4, 92.0, and 88.8, respectively, on the PARQ VAS. Perceived adherence to exercise was lower but remained steady, with corresponding means of 54.5, 64.1, 61.2, 63.0, and 54.3, respectively. Using generalized estimating equation analysis, factors associated with higher perceived adherence to medications included perceived helpfulness of medications and lower disease severity; those associated with higher perceived adherence to exercise were younger age of the child, child involvement in responsibility for treatment, and higher perceived helpfulness of the treatment.

Conclusion

Belief in helpfulness of treatment is associated with higher parental perceived adherence to treatment.  相似文献   
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Perhaps the most significant link in achieving the nation's immunization objectives is the extent of parental knowledge. Admittedly, this is a weak link. The 1990 federal objectives calling for an official format using common guidelines for completion of immunizations, though well-conceived, has not been used exclusively by health care givers. The lack of accord has permitted the proliferation of many different immunization records that are not only confusing to parents, but also to health care providers at times. A standard national immunization record could be an essential element in strengthening the weak link of parental knowledge of immunizations and stressing the importance of preserving such a record for a lifetime.  相似文献   
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As most mechanisms of adaptive immunity evolved during the divergence of vertebrates, the immune systems of extant vertebrates represent different successful variations on the themes initiated in their earliest common ancestors. The genes involved in elaborating these mechanisms have been subject to exceptional selective pressures in an arms race with highly adaptable pathogens, resulting in highly divergent sequences of orthologous genes and the gain and loss of members of gene families as different species find different solutions to the challenge of infection. Consequently, it has been difficult to transfer to the chicken detailed knowledge of the molecular mechanisms of the mammalian immune system and, thus, to enhance the already significant contribution of chickens toward understanding the evolution of immunity. The availability of the chicken genome sequence provides the opportunity to resolve outstanding questions concerning which molecular components of the immune system are shared between mammals and birds and which represent their unique evolutionary solutions. We have integrated genome data with existing knowledge to make a new comparative census of members of cytokine and chemokine gene families, distinguishing the core set of molecules likely to be common to all higher vertebrates from those particular to these 300 million-year-old lineages. Some differences can be explained by the different architectures of the mammalian and avian immune systems. Chickens lack lymph nodes and also the genes for the lymphotoxins and lymphotoxin receptors. The lack of functional eosinophils correlates with the absence of the eotaxin genes and our previously reported observation that interleukin- 5 (IL-5) is a pseudogene. To summarize, in the chicken genome, we can identify the genes for 23 ILs, 8 type I interferons (IFNs), IFN-gamma, 1 colony-stimulating factor (GM-CSF), 2 of the 3 known transforming growth factors (TGFs), 24 chemokines (1 XCL, 14 CCL, 8 CXCL, and 1 CX3CL), and 10 tumor necrosis factor superfamily (TNFSF) members. Receptor genes present in the genome suggest the likely presence of 2 other ILs, 1 other CSF, and 2 other TNFSF members.  相似文献   
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PURPOSE: To assess the health status of the Hispanic population of Orange County, Florida. METHODS: The methodology utilized secondary data for 66 ethnically identified indicators in a comparative framework applied for a 5-year period (1997-2001). FINDINGS: Orange County Hispanics are younger with lower per capita income than their Florida peers, less likely to be White, and much more likely to be of Puerto Rican origin. Relative to the Hispanic populations in the selected peer counties and statewide, Orange County Hispanics have higher age-adjusted death rates for a majority of disease categories and conditions, such as breast, lung, and prostate cancers; chronic liver disease and cirrhosis; diabetes mellitus; pneumonia and influenza; stroke; acquired immunodeficiency syndrome; motor vehicle accidents; and infant, neonatal, and child mortality. Orange County Hispanics did better in comparison to Orange non-Hispanics, with lower age-adjusted death rates for major causes of death such as heart disease, cancer, and stroke. However, for many indicators, the 5-year trends for Orange County Hispanics are moving in an unfavorable direction in contrast to the trends for non-Hispanics, which are either stable or improving. CONCLUSION: Comparative assessments of Hispanic populations using secondary data enable the development of a comprehensive health status profile. However, this approach is currently constrained by the limited number of ethnically identified indicators and, especially for Hispanics, problems in the accuracy and consistency of the assignment to racial categories and subsequent reporting.  相似文献   
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