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981.
We examined the genetic associations of the G-2548A polymorphism in the promoter of the leptin (LEP) gene and the Gln223Arg (Q223R) polymorphism of the leptin receptor (LEPR) gene with obesity. Two hundred twenty-six obese aboriginal subjects (BMI > or = 27 kg/m2) and 182 aboriginal subjects with normal weight (BMI < 25 kg/m2) participated in this study. The polymorphisms of LEP G-2548A and LEPR Q223R were genotyped by polymerase chain reaction/restriction fragment length polymorphism, and their anthropometric characteristics were measured. Levels of leptin, triglycerides, and cholesterol were measured after overnight fasting. We found that the frequencies of the LEP G/G homozygote (22.6%) with Mendelian recessive (chi2 = 7.89, p = 0.005) and codominant (chi2 = 7.93, p = 0.02) models to be higher in the extremely obese subjects (BMI > or = 35 kg/m2) than in normal weight subjects (6.9%) but not in moderately obese subjects (35 > BMI > or = 27 kg/m2). There was no difference in genotypic frequency of the LEPR Q223R polymorphism between the extreme obese and control groups. We suggest that the LEP -2548 G/G homozygote plays a genetic recessive role in the development of extreme obesity in Taiwanese aborigines.  相似文献   
982.
983.
The development, progression, and recurrence of autoimmune diseases are frequently driven by a group of participatory autoantigens. We identified and characterized novel autoantigens by analyzing the autoantibody binding pattern from horses affected by spontaneous equine recurrent uveitis to the retinal proteome. Cellular retinaldehyde-binding protein (cRALBP) had not been described previously as autoantigen, but subsequent characterization in equine recurrent uveitis horses revealed B and T cell autoreactivity to this protein and established a link to epitope spreading. We further immunized healthy rats and horses with cRALBP and observed uveitis in both species with typical tissue lesions at cRALBP expression sites. The autoantibody profiling outlined here could be used in various autoimmune diseases to detect autoantigens involved in the dynamic spreading cascade or serve as predictive markers.  相似文献   
984.
In recent years it has become increasingly clear that the metallothionein (MT) family of proteins is important in neurobiology. MT-I and MT-II are normally dramatically up-regulated by neuroinflammation. Results for MT-III are less clear. MTs could also be relevant in human neuropathology. In Alzheimer disease (AD), a major neurodegenerative disease, clear signs of inflammation and oxidative stress were detected associated with amyloid plaques. Furthermore, the number of cells expressing apoptotic markers was also significantly increased in these plaques. As expected, MT-I and MT-II immunostaining was dramatically increased in cells surrounding the plaques, consistent with astrocytosis and microgliosis, as well as the increased oxidative stress elicited by the amyloid deposits. MT-III, in contrast, remained essentially unaltered, which agrees with some but not all studies, of AD. In situ hybridization results in a transgenic mouse model of AD amyloid deposits, the Tg2576 mouse, which expresses human Abeta precursor protein harboring the Swedish K670N/M671L mutations, are in accordance with results in human brains. Overall, these and other studies strongly suggest specific roles for MT-I, MT-II, and MT-III in brain physiology.  相似文献   
985.
986.
987.
The purpose of this article is to illustrate a new classification of resin based aesthetic materials laying on the characterization of their matrix and their filler morphology. Four samples per material have been prepared for SEM evaluation. Each sample has been treated with chloroform to dissolve its matrix in order to evidence the filler morphology. A general schema of four different matrix systems which characterize the material's level of hydrophobicity can be put in evidence. The subsequent filler analysis individuates a more complex schema based on filler size and construction. A new classification based on matrix nature and filler morphology has been proposed. Based on this concept mechanical and aesthetic characteristics of the materials can be presumed.  相似文献   
988.
Taiwanese aborigines have a high prevalence of hyperuricemia and gout. Uric acid levels and urate excretion have correlated with dopamine-induced glomerular filtration response. MAOs represent one of the major renal dopamine metabolic pathways. We aimed to identify the monoamine oxidase A (MAOA, Xp11.3) gene variants and MAO-A enzyme activity associated with gout risk. This study was to investigate the association between gout and the MAOA single-nucleotide polymorphisms (SNPs) rs5953210, rs2283725, and rs1137070 as well as between gout and the COMT SNPs rs4680 Val158Met for 374 gout cases and 604 controls. MAO-A activity was also measured. All three MAOA SNPs were significantly associated with gout. A synonymous MAOA SNP, rs1137070 Asp470Asp, located in exon 14, was associated with the risk of having gout (P = 4.0 × 10?5, adjusted odds ratio 1.46, 95% confidence intervals [CI]: 1.11–1.91). We also showed that, when compared to individuals with the MAOA GAT haplotype, carriers of the AGC haplotype had a 1.67-fold (95% CI: 1.28–2.17) higher risk of gout. Moreover, we found that MAOA enzyme activity correlated positively with hyperuricemia and gout (P for trend = 2.00 × 10?3 vs. normal control). We also found that MAOA enzyme activity by rs1137070 allele was associated with hyperuricemia and gout (P for trend = 1.53 × 10?6 vs. wild-type allele). Thus, our results show that some MAOA alleles, which have a higher enzyme activity, predispose to the development of gout.  相似文献   
989.
The coefficient of variation CV (%) is widely used to measure the relative variation of a random variable to its mean or to assess and compare the performance of analytical techniques/equipments. A review is made of the existing multivariate extensions of the univariate CV where, instead of a random variable, a random vector is considered, and a novel definition is proposed. The multivariate CV obtained only requires the calculation of the mean vector, the covariance matrix and simple quadratic forms. No matrix inversion is needed which makes the new approach equally attractive in high dimensional as in very small sample size problems. As an illustration, the method is applied to electrophoresis data from external quality assessment in laboratory medicine, to phenotypic characteristics of pocket gophers and to a microarray data set.  相似文献   
990.
Cercidiphylloxylon spenceri(Brett)Pearson is described from the Lizigou Formation,Palaeocene in China.The growth rings are distinct; pores are diffuse,solitary,with somewhat angular outlines in cross section;vessel elements long with long scalariform perforation plates; intervessel pitting is opposite to scalariform; fibertracheids are present; axial parenchyma is scarce; rays are mostly biseriate and heterogeneous.All wood characters of the fossil specimen fall into the range of those of extant Cercidiphyllum(Cercidiphyllaceae).The finding is one of the earliest fossil wood records of Cercidiphyllaceae.  相似文献   
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