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One diagnostic criterion for metabolic syndrome is obesity from the accumulation of visceral fat; others include abdominal circumference and area of visceral fat as measured by computed tomography (CT) at the umbilical level. We evaluated visceral fat using frequency-selective excitation magnetic resonance (MR) imaging SPAIR (spectral attenuation with inversion recovery) water suppression THRIVE (3D T1-high resolution isotropic volume examination). Fifty of 70 slices with 2-mm interval were used to render and measure volume of visceral fat ranging within 10 cm of the umbilicus; the area of visceral fat at the umbilical level was also measured. Imaging was completed using breath hold within 14 s. Image processing was easier than using CT.  相似文献   
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This cross-sectional study was conducted to examine whether the obstructive sleep apnea syndrome (OSAS) is associated with elevation of the pulse wave velocity (PWV) and increase in the plasma levels of C-reactive protein (CRP), both of which are known markers of cardiovascular risk, and also to determine if the concurrent presence of the metabolic syndrome might exacerbate this elevation in the levels of these cardiovascular risk markers in subjects with OSAS. With these objectives, the PWV and serum CRP were measured in 184 subjects attending a sleep clinic. It was found that the PWV and CRP were higher in the subjects with OSAS (n=94) than in those without OSAS (n=90). Furthermore, among the subjects with OSAS, the PWV and CRP were higher in those with the concurrent presence of the metabolic syndrome (n= 41; PWV=1,562+/-19 cm/s; CRP=1.8+/-0.2 mg/l) than in those without metabolic syndrome (n=53; PWV=1,432+/-21 cm/s; CRP=1.2+/-0.1 mg/l) (p<0.05). A general linear model analysis demonstrated that OSAS and metabolic syndrome were independently associated with elevated PWV and increase of the plasma levels of CRP. OSAS appears to be associated with increased cardiovascular risk, as reflected by both elevated PWV and increase of the plasma CRP. The concurrent presence of metabolic syndrome may exacerbate this increase in cardiovascular risk in subjects with OSAS. Therefore, the concurrent presence of metabolic syndrome may constitute an additive cardiovascular risk factor in subjects with OSAS.  相似文献   
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Background and Aims:  The aim of this study was to determine which mouse strains exhibit tolerance to cooling when fertilized oocytes have been stored at 4°C.
Methods:  In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results:  Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion:  Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50)  相似文献   
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Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial activity against a mouse infection model and may be useful for the clinical treatment of plague.  相似文献   
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To elucidate the effect of fibroblast growth factor on the phenotypical conversion of fibroblasts to mesothelial cells, both immunohistochemical and ultrastructural examinations were carried out on cultured spheroids that were composed of fibroblasts obtained from the parietal pleura of rats with and without addition of antifibroblast growth factor receptor antibody. In the present study, antifibroblast growth factor receptor antibody was employed to block the effect of the autocrine component of fibroblast growth factor in the culture medium. Phenotypical conversion from fibroblast to mesothelial cells was clearly blocked in the experimental group, to which culture medium had been added with antifibroblast growth factor receptor antibody, whereas the control group, cultured without addition of antifibroblast growth factor receptor antibody, showed phenotypical conversion of fibroblasts that was confirmed by the development of macula adherens, microvilli, and positive expression of cytokeratin. These results indicate the possibility that fibroblast growth factor plays a key role in the process of phenotypic conversion of fibroblasts to regenerated mesothelial cells.  相似文献   
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In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development.  相似文献   
8.
A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
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