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排序方式: 共有836条查询结果,搜索用时 46 毫秒
1.
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
2.
Kazuhiko Yanai Tatsuo Ido Kiichi Ishiwata Jun Hatazawa Toshihiro Takahashi Ren Iwata Taiju Matsuzawa 《European journal of nuclear medicine and molecular imaging》1986,12(3):141-146
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors. 相似文献
3.
Flow karyotypes and chromosomal DNA contents of genus Triticum species and rye (Secale cereale) 总被引:3,自引:0,他引:3
Jai-Heon Lee Youzhi Ma Toshiyuki Wako Lian Cheng Li Kee-Young Kim Seong-Whan Park Susumu Uchiyama Kiichi Fukui 《Chromosome research》2004,12(1):93-102
The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length. 相似文献
4.
Atsushi Nakahira Hitoshi Ogino Hiroaki Sasaki Nobuyuki Katakami 《European journal of cardio-thoracic surgery》2007,32(2):388-390
Malignant pulmonary artery tumors represented by sarcomas are rare, but fatal. Early diagnosis and radical surgical resection offer the only chance for survival. However, surgical intervention has some challenging aspects, and prognosis is poor even after tumor resection. We report a case of a pulmonary artery sarcoma between the right ventricular outflow tract and the pulmonary artery branches. The tumor was aggressively extracted with reconstruction using a cryopreserved pulmonary valved allograft, followed by adjuvant chemoradiotherapy. At 56 months after surgery, the patient is well without any evidence of recurrence, demonstrating that aggressive surgical resection with adjuvant chemoradiotherapy can prolong survival. 相似文献
5.
Takahito Adachi Makoto Takeuchi Satomi Uno Motohisa Kato Kiichi Miya Shigetoyo Saji 《Surgery today》1997,27(12):1144-1149
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor
activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive
activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced
by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA
synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with
serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted
DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth
factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide
(MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate
dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced
in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment
of liver failure. 相似文献
6.
K Ohno Y Morotomi K Harumoto M Ueda M Nakahira T Nakamura T Azuma T Moriuchi T Yoshida C Shiokawa T Nakaoka 《Zeitschrift für Kinderchirurgie》2006,16(3):155-159
AIM: Bone scintigraphy was performed to elucidate the effects of the Nuss procedure for pectus excavatum on the bony thorax. METHODS: Eight boys and 6 girls (5 - 24 years of age) underwent bone scintigraphy, using (99m)Tc-HMDP. Eleven patients were studied 5 to 21 days after the Nuss procedure; 6 were studied 20 to 24 months after the operation before bar removal. Three of 14 were studied twice after the Nuss procedure and before bar removal. RESULTS: In the early postoperative phase, RI accumulation was found at the sternum and ribs in only 1 of 6 patients under 9 years of age, whereas in all 5 older patients, RI had accumulated at the sternum. Scintigrams before bar removal revealed, regardless of age, hot spots at the lateral ribs in contact with the bar and at the costochondral junctions where the bar passed through the intercostal spaces. Furthermore, chest roentgenograms showed the deformed lateral ribs in contact with the bar. CONCLUSIONS: The Nuss procedure creates minute fractures at the sternum and the ribs, especially in older patients. The bar deforms the ribs and restrains the growth of the thorax. Furthermore, it constantly rubs against the ribs and can therefore cause late complications. Bone scintigraphy may determine the appropriate timing for bar removal. 相似文献
7.
8.
We studied the contribution of atrial contraction to ventricular filling by modelling the right heart and the associated vasculature.
Right atrial and ventricular contractions were represented by periodically varying volume elastances which are independent
of loading conditions. The values of these elastances were experimentally determined. The systemic veins, the tricuspid valve
and the pulmonary arteries were all represented by impedance networks. For these impedances we used as much experimentally
obtained information as possible. The dynamic pressure and flow waveforms observed in the model under control conditions generally
agreed with those reported in the literature. We therefore proceeded to analyze the effects of changing the time interval
between atrial systole and ventricular systole, atrial contractility, heart rate, and blood inertance. There was an optimal
atrial systole-ventricular systole interval of about 0.1 sec for ventricular filling. Stroke volume of the ventricle was enhanced
by an increase in atrial contractility, a decrease in heart rate, and an increase in blood inertance. The effect of changing
atrial compliance was found to be dependent on heart rate. Contribution of atrial contraction to ventricular filling was also
found to be more significant during exercise than at rest. 相似文献
9.
Hirofusa Shirai Yoshiaki Inaki Kiichi Takemoto 《Macromolecular chemistry and physics.》1974,175(7):2047-2053
A series of the copper(II) complexes of the type CuL4X2 (L: ligand, X: anion) was prepared with the following substituted imidazoles as ligands 2-ethyl- ( 1a ), 2-ethyl-4-methyl- ( 1b ), 2-phenyl- ( 1c ), 2-undecyl- ( 1d ), and 2-heptadecylimidazole ( 1e ). The structures of these complexes were confirmed by elemental analysis, reflection spectra of the crystals as well as IR-spectroscopy. Polymerization of acrylonitrile was tested in the presence of each imidazole-copper(II) complex in dimethyl sulfoxide solution. 相似文献
10.
Koichi Kondo Yoshiyuki Miwa Kiichi Takemoto 《Macromolecular chemistry and physics.》1983,184(6):1171-1178
Active β-alanine esters having dipeptide groups, which are capable of forming hydrogen bonds between the side chains, were prepared in the form of hydrogen chloride salts. The polycondensation of these salts was studied in non-polar solvents, in the presence of triethylamine. In the case of the ester with β-alanyl-β-alanine as dipeptide moiety, the polycondensation proceeded smoothly in chloroform solution. To explain the characteristic feature of the polycondensation, an ordered aggregation of the ester molecules is assumed to play an important role. The ester with glycylglycine as dipeptide moiety, however, did not undergo a polycondensation. 相似文献