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OBJECTIVE: To evaluate the neuropsychological and psychiatric sequelae of unilateral posterior pallidotomy for treatment of PD. METHODS: Patients with idiopathic PD completed baseline and 3- and 6-month assessments after random assignment to an immediate surgery (n = 17) or medical management (n = 16) group. RESULTS: Compared with the medical management group, the immediate surgery group with single lesions centered on the posterior internal pallidum showed superior naming and response inhibition, better verbal recall at 6 months, but greater distractibility, a tendency toward lower phonemic fluency, and a transient (3 months' only) semantic fluency deficit. The group with left lesions had more neuropsychological deficits than the group with right lesions or the medical management group, although these occurred mainly at 3 (but not 6) months. At 6 months, the patients with left lesions showed better verbal memory retention than the patients with right lesions. On most measures, the pattern of individual clinical change did not differ as a function of surgery or lesion laterality, with the exception of a higher frequency of decline in phonemic fluency in the patients with left lesions at 6 months. Although psychiatric status did not change overall, a history of depression tended to increase the risk of a depressive episode following surgery. CONCLUSIONS: Well-targeted, uncomplicated, unilateral pallidotomy does not produce overall neuropsychological or psychiatric change, although there are subtle changes on specific measures sensitive to frontal lobe function.  相似文献   
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BACKGROUND: Information about the influence of housing and occupant characteristics on mite allergen concentrations is crucial to determine which methods could be used to decrease exposure of susceptible subjects. OBJECTIVES: To identify housing and occupant characteristics that are associated with mite allergen concentrations in house dust collected from living rooms and mattresses. METHODS: We collected dust samples from 750 homes in the northeastern US. The influence of various characteristics on concentrations of mite allergens (Der p 1 and Der f 1) was studied using multiple linear regression analysis. RESULTS: Some characteristics, like absence of air conditioners, the presence of mold or mildew, and a lower temperature were consistently associated with higher concentrations of both mite allergens in dust from all sampling locations. However, none of these factors changed Der p 1 or Der f 1 concentrations by more than a factor of 2. People of white ethnic background had roughly two times higher mite allergen concentrations, while family income, family size, and education level only marginally influenced mite allergen concentrations. CONCLUSIONS: Various housing characteristics have some influence on mite allergen concentrations, and could possibly be used to decrease exposure of susceptible subjects. However, only a limited percentage of the variation in mite allergen concentrations was explained by these characteristics.  相似文献   
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BACKGROUND: Variants in the CD14 gene (CD14) are hypothesized to be associated with atopic disorders. However, most studies have only investigated one polymorphism in this gene. OBJECTIVE: We sought to study the association of 5 single nucleotide polymorphisms (SNPs) in the 5' flanking region of CD14 with eczema and serum IgE levels in young children. METHODS: We genotyped 5 SNPs in an approximately 6.5-kb region in the 5' region of CD14 in 344 2-year-old white children from 2 birth cohorts in the northeastern United States. We examined the relation of both single SNPs and haplotypes in CD14 with the atopic outcomes. RESULTS: Two SNPs were significantly associated with eczema. In dominant models adjusted for potential confounders, SNP rs2569193 was associated with significantly decreased risk for eczema (odds ratio [OR] for CT/TT vs CC, 0.5; 95% CI, 0.3-0.8), whereas SNP rs2569190 (also reported as the C-159T) was associated with significantly increased risk for eczema (OR for CT/TT vs CC, 2.3; 95% CI, 1.4-3.8). The CT/TT genotypes of SNP rs2569190 also had higher geometric means of serum IgE than the CC genotype (24.6 vs 15 IU/mL, P = .025). Haplotype analyses provided results similar to those of the single SNP analyses. CONCLUSIONS: Our results contradict previous reports that have found a protective effect of the T allele of SNP rs2569190 (C-159T) against atopic disorders. Nevertheless, these results confirm the importance of polymorphisms in CD14 in the development of atopy, and future studies of this gene region will need to account for linkage disequilibrium and environmental exposures unique to the study population.  相似文献   
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Forty-two cases of peripheral neuroepithelioma (PN) retrieved from the files of the National Cancer Institute (Bethesda, MD) and the Pathology Department of Padua University, Italy, were reviewed. No sex predilection was observed (25M/17F) and ages ranged from 7 to 54 yr (median 22 yr). Roughly a third of the tumors were thoracopulmonary ("Askin tumor"), a third were axial, and a third were in extremities. A lobular pattern with rosettes or pseudo-rosettes characterized PN. Seventeen cases showed a strong diastase-sensitive PAS positivity. Transitional areas with an Ewing's-like appearance and, in one case, transition to malignant nerve sheath tumor have been documented. The presence of neuron specific enolase (NSE), S-100 protein, HNK-1, neurofilaments, vimentin, keratin (AE1-AE3), beta 2-microglobulin, chromogranin A, and synaptophysin was investigated using the avidin-biotin technique. Immunocytochemically, NSE (95% of cases), beta 2-microglobulin (77.5%), synaptophysin (73.3%), and S-100 protein (67.5%) were the most consistently positive markers. Ultrastructurally, PN is characterized by a primitive appearance, although it was routinely possible to recognize neural features such as primitive neuritic extensions and dense core granules, either in the cytoplasm or in the cellular processes. In our experience, a light microscopic picture of a primitive round cell tumor with a lobular pattern, and particularly with rosettes when present, with NSE and beta 2-microglobulin positivity by immunocytochemistry, ideally with positive synaptophysin, along with supportive electron microscopy, is required for the diagnosis of PN. Conversely, no one feature alone is generally sufficient for diagnosis, but does allow distinction from extraosseous Ewing's, which (like osseous Ewing's) lacks features of neural differentiation.  相似文献   
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The capacity of a primitive human retinoblastoma cell line (Y-79) to differentiate into several cell types of normal human retina was investigated. Cells were studied in suspension and monolayer cultures, in serum-free or serum-supplemented medium, and in the presence or absence of differentiating agents such as N6O12-dibutyryl adenosine 3',5'-cyclic monophosphate (dbc-AMP) and sodium butyrate (Nabut). Electron microscopy, immunohistochemistry for detection of myelin basic protein (MBP), and formaldehyde-induced fluorescence (FIF) for catecholamines were performed. Treated cells exhibited morphologic characteristics supportive of differentiation toward photoreceptors, conventional neurons and glial cells, increased FIF reactivity, and MBP expression. Growth in serum-free medium without differentiating agents led to a similar but less enhanced morphologic differentiation. These results confirm the concept that human retinoblastoma originates from a primitive neuroectodermal multipotential cell.  相似文献   
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Background  

We examined the association between single nucleotide polymorphisms (SNPs) in loci encoding surfactant protein A (SFTPA) and risk of wheeze and persistent cough during the first year of life among a cohort of infants at risk for developing asthma.  相似文献   
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