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11.
The favorable therapeutic effect of preoperative portal vein embolization (PVE) was analyzed by assessing various volumetric, cell kinetic and morphometric parameters and examining histologically the embolized and nonembolized lobes of 15 patients who underwent extended right lobectomy 2 to 3 weeks after PVE. Each lobar volume was calculated from computed tomography (CT) images, hepatocyte proliferation was evaluated by assessing proliferative cell nuclear antigen (PCNA) expression and mitosis, hepatocyte apoptosis was evaluated by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the hepatocyte numerical density as well as the sinusoidal volumetric ratio (Vvs) and the mean hepatocyte volume (Cv) were calculated using morphometric methods. PVE induced hepatocyte apoptosis and atrophy of the embolized lobe (from 798 +/- 213 to 708 +/- 222 cm3; P < .05). The increased sinusoidal volume in this lobe (17.7% +/- 4.5% and 21.7% +/- 5.7%, periportal and pericentral area, respectively) may have been attributable to hepatocyte deletion. Cells in the nonembolized lobe entered a highly active phase of proliferation within 2 weeks after PVE. Further evidence of cellular proliferation was provided by the increased nonembolized lobar volume (from 379 +/- 132 to 545 +/- 130 cm3; P < .01) and numerical density of hepatocyte nuclei (Nv) (5.38 +/- 1.26 vs. 3.11 +/- 0.85 x 10(5)/mm3; P < .01, nonembolized vs. embolized lobe, respectively). In conclusion, these results indicate that the favorable effect of PVE is attributable to a net gain of functional hepatocyte mass and/or early induction of hepatocyte proliferation following hepatectomy. 相似文献
12.
Using spin-on glass (SOG) as an adhesive, an Si wafer with thermal oxide was successfully bonded to one with an RF-sputtered Si3N4 film. This ensures that SOG films are effective in bonding Si wafers to less reactive surfaces than Si or SiO2 such as silicon nitride. It was also found that the previously reported bonding procedure can be simplified by suppressing the spin-induced radial striations of the SOG films. 相似文献
13.
Y Hata S Morita Y Noda R Kawasaki Y Morita T Awatani T Horimi 《Canadian Metallurgical Quarterly》1998,25(6):901-905
OBJECTIVE: The degree to which patient education in the areas of diet, exercise, and stress management can improve symptoms of irritable bowel syndrome (IBS) through healthier lifestyle behaviors is unknown. The aim of this study was to determine the effects of outpatient education on the short and long term outcomes, and the association between health-promoting behaviors and symptoms. METHODS: Pender's Health Promotion Model provided the theoretical framework. The study had a prospective longitudinal design. A consecutive sample of 52 adult outpatients with IBS attended a structured class that taught health-promoting modifications of lifestyle. Participants completed the Health-Promoting Lifestyle Profile (HPLP) and selected items from a Bowel Disease Questionnaire (BDQ) before the class and 1 month and 6 months later. Spearman rank correlations were used to assess the association between HPLP and symptom scores. Wilcoxon rank sum tests compared changes in scores versus their baseline values. RESULTS: Response rates at 1 and 6 months were 75% and 83%, respectively. Results revealed significant 1- and 6 month-improvements in pain and Manning symptoms (p < 0.01) and in some HPLP scores (exercise at 1 month, p < 0.05; stress management at 6 months, p < 0.01). Significant associations were found between some, but not all, HPLP and symptom scores over time. CONCLUSION: A structured IBS educational class for patients with IBS improved symptoms and some health-promoting behaviors. However, relationships among specific behaviors and specific symptoms did not consistently correspond with this improvement. 相似文献
14.
Inhibition of plasma endothelin-1 concentration by captopril in patients with essential hypertension
The aim of this study was to determine whether captopril has any effect on plasma endothelin-1 (ET-1) concentration in patients with essential hypertension. Nine normotensives and eleven hypertensives were included in this study. Blood pressure and pulse rate were monitored before and at 60 min after captopril ingestion (25 mg). Simultaneously, blood samples for plasma ET-1 and plasma renin activity (PRA) determination were obtained. In the normotensives, captopril treatment resulted in a significant rise in PRA, but without statistical changes in blood pressure and plasma ET-1. By contrast, in the hypertensives, although PRA elevated similarly after captopril, both blood pressure and plasma ET-1 decreased significantly compared with their respective preloading level. These data suggest that the blood pressure-lowering effect of captopril in essential hypertension may be at least in part, mediated by its inhibition of ET-1 production from the vascular endothelium. 相似文献
15.
Uchiyama K. Arakawa F. Narita S. Aoki H. Kawasaki I. Matsui S. Yamamoto M. Nakagawa N. Kudo I. 《Micro, IEEE》1993,13(5):12-22
The Gmicro/500, which features a RISC-like dual-pipeline structure for high-speed execution of basic instructions and represents a significant advance for the TRON architecture, is presented. Upwardly-object-compatible with earlier members of the Gmicro series, this microprocessor uses resident dedicated branch buffers to greatly enhance branch instruction execution speed. Its microprograms simultaneously use dual execution blocks to execute high-level language instructions effectively. Fabricated with a 0.6-μm CMOS technology on a 10.9-mm×16-mm die, the chip operates at 50/66 MHz and achieves a processing rate of 100/132 MIPS 相似文献
16.
Y Tajima M Kawasaki K Kurihara T Ueha S Yokose 《Canadian Metallurgical Quarterly》1998,43(11):873-877
Basic fibroblast growth factor (bFGF) and heparan sulphate (HS) were detected immunohistochemically in mandibular condylar cartilage, and the findings compared with those on epiphyseal articular cartilage. In the condylar cartilage, both bFGF and HS were localized in chondrocytes throughout the various zones including the fibrous, proliferative, mature-cell and hypertrophic zones: bFGF immunostaining was most significant in the proliferative and mature-cell zones, while intense staining for HS was found mainly in the hypertrophic zone. Immunoreaction for bFGF was detected in the nuclei of chondrocytes, whereas HS staining was observed in the cytoplasm. In articular cartilage, only chondrocytes beneath the superficial zone (intermediate zone) demonstrated both bFGF and HS immunoreactivities. Chondrocytes in the deeper calcifying region of the articular cartilage did not immunoreact for either bFGF or HS. These findings suggest that, in contrast to the epiphyseal articular cartilage, a continuous bFGF-mediated remodelling of cells and matrix takes place in mandibular condylar cartilage during the process of endochondral ossification. 相似文献
17.
Hideyuki Yoshimatsu Hitoshi Kawasaki Akiyoshi Osaka 《Journal of Materials Science》1988,23(1):332-336
Zr-Al organometallic compounds have been spray-dried and heated at temperatures 600 to 1400°C to prepare ZrO2-Al2O3 composite powders. The powders consist of balloon-like particles 0.5 to 2 m in diameter with homogeneously dispersed tetragonal ZrO2 grains 0.1 to 0.2 m in diameter. The tetragonal fraction of ZrO2 in the composite powders is higher than that in the powders prepared from sols of Zr(OBun)4 and Al[OCH(CH3)2]3. The fraction is affected by the organofunctional group in the Zr-Al compounds.Zr(OBun)4 = Zr(OC4Hgn)4; Al[OCH(CH3)2]3 = Al(OPri)3. 相似文献
18.
连铸中间包内三维湍流流动的数值模拟 总被引:11,自引:0,他引:11
连铸中间包的操作条件决定了其内流动现象的复杂性,为此,本文选择两种不同的湍流模型k-ε和LES(Largeeddysimulation),建立了描述连铸中间包内三维湍流流动的数学模型,并实施了数值计算和模型验证,对单流中间包内的流动现象进行了描述,考察了有,无流动控制情况下中间包内的流动特征和湍流模型的合理性,结果表明,合理的流动控制有利于中间包内非金属夹杂的上浮和吸附,用k-ε模型基本上能够描述 相似文献
19.
Dr. Daisuke Fujiwara Kousuke Mihara Ryo Takayama Yusuke Nakamura Prof. Mitsuhiro Ueda Prof. Takeshi Tsumuraya Prof. Ikuo Fujii 《Chembiochem : a European journal of chemical biology》2021,22(24):3406-3409
Conformationally constrained peptides hold promise as molecular tools in chemical biology and as a new modality in drug discovery. The construction and screening of a target-focused library could be a promising approach for the generation of de novo ligands or inhibitors against target proteins. Here, we have prepared a protein kinase-focused library by chemically modifying helix-loop-helix (HLH) peptides displayed on phage and subsequently tethered to adenosine. The library was screened against aurora kinase A (AurA). The selected HLH peptide Bip - 3 retained the α-helical structure and bound to AurA with a KD value of 13.7 μM. Bip - 3 and the adenosine-tethered peptide Bip - 3 - Adc provided IC50 values of 103 μM and 7.7 μM, respectively, suggesting that Bip - 3 - Adc bivalently inhibited AurA. In addition, the selectivity of Bip - 3 - Adc to several protein kinases was tested, and was highest against AurA. These results demonstrate that chemical modification can enable the construction of a kinase-focused library of phage-displayed HLH peptides. 相似文献
20.
Laser-Sintered Barium Titanate 总被引:1,自引:0,他引:1
Toshihiro Kasai Yoshiharu Ozaki Hideki Noda Kenji Kawasaki Kei Tanemoto 《Journal of the American Ceramic Society》1989,72(9):1716-1718
Laser sintering of alkoxy-derived ultrafine BaTiO3 powders was investigated. The temperature increases of the sample with laser irradiation were measured with a thermocouple. It was found that laser irradiation could generate enough heat to sinter ceramics. A slurry was prepared by mixing an alkoxy-derived BaTiO3 powder, binder additives, solvent, and plasticizer. The slurry was tape cast and dried to give a green sheet. The green sheet was laser sintered and was then characterized by SEM, XRD, and density measurements. The effect of burnout before laser irradiation and the characteristic microstructure of laser-sintered BaTiO3 are described. 相似文献