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排序方式: 共有10000条查询结果,搜索用时 156 毫秒
1.
2.
Shigeko Tanaka Minoru Yoshiyama Yukihiro Imanishi Koichi Nakahira Takashi Hanaki Yukari Naito Mizue Imai Masahiro Tanaka 《Magnetic resonance in medical sciences》2006,5(4):207-210
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
3.
Takayuki Sakurai Satoshi Watanabe Minoru Kimura Masahiro Sato 《Reproductive Medicine and Biology》2006,5(1):43-50
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
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
4.
The role of hypertension and antihypertensive drugs in cardiovascular complications was evaluated in 380 elderly people living in the Tokyo Metropolitan Gerontology Center. The subjects were classified into four groups according to the presence or absence of hypertension and their antihypertensive treatment, and followed up prospectively for 5 years from 1979 to 1984. The average age of each group was 74 to 76 years. Cerebrovascular disease was observed in 19.3% of male hypertensives and 10.1% of male normotensives (p = 0.078). The drug treated group revealed no cerebral hemorrhage and less cerebral infarction. This tendency was not observed in females. Ischemic heart disease was prevalent in the drug treated group (10.9% vs 4.5%, p = 0.023) irrespective of blood pressure level. Risk factors such as body mass index, skinfold thickness, serum cholesterol, albumin, creatinine, blood urea nitrogen and uric acid at entry were elevated in the drug treated group. Diuretics were used in 92% of the drug treated group; in 53% as monotherapy and in 39% as combination therapy with other antihypertensive agents. The metabolic effect of diuretics may increase the incidence of ischemic heart disease in the elderly. We might conclude that hypertension in the aged accelerates cerebrovascular complications, and that antihypertensive treatment is effective even in this group. However, the wide use of diuretics could increase the incidence of ischemic heart disease. Careful selection of antihypertensive drugs as well as dose adjustment are needed in the treatment of elderly hypertensives. 相似文献
5.
Sachiko Goto Akiyoshi Tsuji Teiko Murai Minoru Nishida Hiroko Tsukano Haruo Watanabe 《Journal of infection and chemotherapy》1998,4(1):16-19
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
6.
Beta2-glycoprotein I-dependent anticardiolipin antibody in early recurrent spontaneous abortion 总被引:1,自引:1,他引:0
Maejima M; Fujii T; Okai T; Kozuma S; Shibata Y; Taketani Y 《Human reproduction (Oxford, England)》1997,12(10):2140-2142
The objective of this study was to assess the clinical significance of
autoimmune anticardiolipin antibody that can react with cardiolipin only in
the presence of beta2-glycoprotein I (beta2-glycoprotein I- dependent
anticardiolipin antibody) in the pathogenesis of early recurrent abortion.
A total of 72 early recurrent spontaneous aborters and 175 normal healthy
women were analysed for the occurrence of beta2- glycoprotein I-dependent
anticardiolipin antibody in serum samples by an enzyme-linked immunosorbent
assay specific for the detection of beta2-glycoprotein I-dependent
anticardiolipin antibody. The incidence of beta2-glycoprotein I-dependent
anticardiolipin antibody in the early recurrent spontaneous aborters was
essentially the same as that of normal women. Thus, the beta2-glycoprotein
I-dependent anticardiolipin antibody seemed to have little, if any,
implication in the pathogenesis of early recurrent spontaneous abortion.
相似文献
7.
The use of the monoclonal antibody Ki-67 in the identification of proliferating cells: application to surgical neuropathology 总被引:6,自引:0,他引:6
In order to test its potential application to surgical neuropathology, the monoclonal antibody Ki-67 was used to demonstrate immunohistochemically the proliferating cells in 40 neoplasms of the nervous system. The antibody, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle, was demonstrated in frozen sections of all lesions. The highest incidence of stained nuclei was found in a metastatic carcinoma (57%). The percentage of stained cells in gliomas was in general agreement with the histologic grade and known biologic behavior of the lesions, ranging from 0.6% in a pilocytic astrocytoma to 12.4% in a glioblastoma multiforme. In the fibrillary astrocytic neoplasms of low cellularity, there were good correlations between the percentages of stained cells and the degrees of nuclear pleomorphism and chromatin density. In meningiomas, schwannomas, and a cerebellar hemangioblastoma, the fractions of labeled nuclei were less than 1%. The percentage of stained cells in pituitary adenomas showed considerable variation among the four cases (0.2-1.5%), the biologic significance of which is unknown. In four of the above cases, Ki-67 staining was performed on air-dried squash preparations with excellent visualization of immunoreactive nuclei. In one case, a hemangioblastoma, no stained nuclei were seen. The results confirm that Ki-67 staining is technically suitable as a diagnostic method, with good correlations between frozen sections and smear preparations. Determination of the replicating cell fraction could become an important additional criterion to predict the biologic behavior of nervous system neoplasms. 相似文献
8.
Masao Amari Katsuji Taguchi Minoru Iwahara K Shibuya Shiro Naoe 《Medical Electron Microscopy》2002,35(4):225-233
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
9.
Changes in central dopaminergic systems with the expression of Shh or GDNF in mice perinatally exposed to bisphenol-A. 总被引:1,自引:0,他引:1
Kazuya Miyagawa Minoru Narita Michiko Narita Keiichi Niikura Hisahiko Akama Yuri Tsurukawa Tsutomu Suzuki 《Nihon shinkei seishin yakurigaku zasshi》2007,27(2):69-75
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
10.
Kentaroh Miyoshi Minoru Naito Tsuyoshi Ueno Shinji Hato Hideo Ino 《General thoracic and cardiovascular surgery》2009,57(11):629-632
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