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11.
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
12.
Sex-specific effects for body mass index (BMI) were explored in a newly established, population-based Norwegian twin panel. The sample includes 5,864 individuals, aged 18–25 years, who responded to a questionnaire containing items for zygosity classification, height, weight, health, health-related behaviors, well-being, and demographic information. Among the 2,570 intact pairs who returned the questionnaire there were 416 identical (MZ) male pairs, 387 fraternal (DZ) male pairs, 528 MZ female pairs, 443 DZ female pairs, and 796 unlike-sexed pairs. Alternate sets of models testing for either sex-specific genetic or environmental parameters were evaluated using structural equation analysis. Results from the most parsimonious model indicated that the genes contributing to variation in BMI are not identical for men and women; rather, some genetic effects were shared by the sexes and some were unique to each sex. Total variation in BMI could be explained by sex-specific additive genetic effects, as well as genetic and non-shared environmental effects common to men and women. Estimates of heritability were .708 for men and .789 for women, and the male-female genetic correlation was 0.622. The series of models specifying sex-specific shared environment also fit the data and suggests that shared environmental factors may be important for males but not for females. The findings raise questions concerning the relationship between sex-specific effects for BMI and sex differences in health outcomes. ©1995 Wiley-Liss, Inc.  相似文献   
13.
BACKGROUND: Synapsin III plays a role in neuronal plasticity and maps to chromosome 22q12-13, a region suggested to be linked to schizophrenia. To determine if synapsin III plays a role in this disease, we searched for polymorphisms in this gene in patients with schizophrenia and controls. METHODS: The synapsin III gene was initially sequenced from 10 individuals with schizophrenia to identify polymorphisms. Association analysis was then performed using 118 individuals with schizophrenia and 330 population controls. Synapsin III expression was studied by immunoblot analyses, and phosphorylation sites were mapped by sequencing trypsin-digested synapsin III fragments phosphorylated with phosphorus-32. RESULTS: A rare, missense polymorphism, S470N, was identified in the synapsin III gene and appeared more frequently in individuals with schizophrenia than in controls (p =.0048). The site affected by the polymorphism, Ser470, was determined to be a substrate for mitogen-activated protein kinase, a downstream effector of neurotrophin action. Phosphorylation at Ser470 was increased during neonatal development and in response to neurotrophin-3 in cultured hippocampal neurons. CONCLUSIONS: Our observations suggest an association of a rare polymorphism in synapsin III with schizophrenia, but further studies will be required to clarify its role in this disease.  相似文献   
14.
The internal fixation of diaphyseal fractures by bone plates is a well recognized treatment. The normal physiological stress of bone is reduced by plates that cause a negative balance of bone-remodeling processes. Many investigators have shown that the degree of stress protection is dependent on the rigidity of the plates. It was the aim of this study to quantify mechanical and morphological changes at different locations in a plated diaphyseal bone as a function of differing plate rigidity. Two types of plates with the same size but different materials were used. The stainless steel plates had a modulus of elasticity and bending stiffness 3.2 times higher than the carbon fiber reinforced carbon plates. Both types of plates were applied to the intact right and left femora of six foxhounds for 6 months. The stiffer stainless steel plates led to a significantly higher bone loss and correspondingly greater loss of mechanical properties. These effects were greatest directly beneath the plate and less with increasing distance from the plate.  相似文献   
15.
Abstract: The identification of familial breast cancer genes heralds an era of directed breast cancer treatment. Currently, two hereditary breast cancer genes have been identified, BRCA-1 and BRCA-2 . Although accounting for only approximately 5% of all breast cancers, they are being used to identify women with germ-line alterations that are at high risk of developing breast or ovarian cancer. With the identification of such genes comes a need for consideration of the ethical issues associated with testing. These genes are also being examined from a biochemical standpoint encompassing both their biological roles and biochemical pathways in which they reside. Such studies are likely to lead to novel breast cancer therapies.  相似文献   
16.
Background :
The aim of this study was to examine nuclear p53 overexpression in transitional cell carcinoma of the bladder, adenocarcinoma of the prostate, and renal cell carcinoma.
Methods :
Forty-four pathologic specimens from 39 bladder cancer patients, 41 prostatic adenocarcinoma, and 39 renal cell carcinoma specimens were analyzed immunohistochemically with D07 monoclonal antibody to detect the expression of the mutant p53 gene. Overexpression was said to occur when the number of positively-stained tumor nuclei were≥ 10% in each specimen. p53 overexpression was correlated with the clinical and histopathological features of these cancers.
Results :
Nuclear p53 overexpression occurred in 18.2% of transitional cell bladder cancer specimens, 12.2% of prostate cancer specimens, and 17.9% of renal cell cancer specimens. Statistical analyses showed that grade, vascular invasion, and necrosis in bladder cancer, a high Gleason score in prostate cancer, and the 1-year mortality rate in renal cancer were significantly related with p53 nuclear overexpression (P<0.05).
Conclusion :
Using the D07 monoclonal antibody, nuclear p53 overexpression is relatively uncommon in urologic malignancies, and moderately correlates with several histopathological and clinical features of urologic malignancies.  相似文献   
17.
In this paper, the authors quantitate the anisotropy of susceptibility effects in an uniaxial trabecular bone model and show its relevance to clinical MR bone mineral density measurements. A physical model is described that quantitates the anisotropic MR behavior of uniaxial trabecular bone. To test the model, a phantom of parallel polyethylene filaments was scanned every 15° between 0° and 90° with respect to the system's main magnetic field (B0). The distal radial metaphysis of a healthy female volunteer was scanned in orthogonal projections. The signal from each phantom image and each radial image was separated in a pixel-wise fashion into R2 and R2′ maps. As predicted, R2′ relaxation showed anisotropic behavior and changed according to sin2 (?), confirming that columnar structures parallel with B0 will cause no MR susceptibility effects. Scans of the distal radius showed that R2′ relaxation was twice as great with the forearm perpendicular to B0 as when it was parallel to it, demonstrating different contributions from struts and columns. For both phantom and radial bone scans, R2 relaxation was isotropic and did not change with object orientation.  相似文献   
18.
We present our experience with twenty children with insulin dependent diabetes mellitus admitted during the past 2 1/2 years. Sixteen patients were admited with acute onset of ketoacidosis while four were having gradual onset. Active and symptomatic treatment was started in all diabetic ketoacidotic patients. One patient died during the acute stage. Eleven patients were followed for 3–6 months or more. Glycosylated hemoglobin was considered as a criteria for control. Three had good control, two fair and six poor control; six developed diabetic ketoacidosis and three developed hypoglycemia  相似文献   
19.
防晒制剂皮肤安全性的实验研究   总被引:2,自引:0,他引:2  
目的 :探讨同一系列不同SPF(sunprotectionfactor)防晒制剂对皮肤的安全性 ,筛选安全有效的防晒制剂配方。方法 :选用白化豚鼠背部去毛 ,分别涂抹SPF值为 15、2 8、30 +三种防晒制剂 ,以UV光源照射 ,波长为 32 0~4 0 0nm ,强度为 ( 16 8± 2 )mW/cm2 。结果 :三种不同SPF防晒制品对实验动物皮肤各时相点反应积分为 ,SPF15组为0 ;SPF2 8组为 1;SPF30 +组为 3。结论 :三种不同SPF值产品对皮肤的光毒性有一定差异 ,提示SPF值在 2 8以内的防晒制剂皮肤安全性较好 ,SPF30 +的防晒制剂对皮肤有一定光毒刺激反应。  相似文献   
20.
Previous work from this laboratory has already indicated that capsaicin, stabilizes the rat lung membrane lipid system on long-term treatment. This stabilization of the membrane is further supported by our present findings that capsaicin pretreatment causes significant inhibition of various chemically induced lipid peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes induced by different chemical irritants such as chloroform, dichloromethane, carbon tetrachloride as well as ferrous sulphate.  相似文献   
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