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排序方式: 共有2522条查询结果,搜索用时 15 毫秒
121.
G Yamada T Igarashi H Sonoda S Morita K Suzuki Y Yoshida S Abe 《Canadian Metallurgical Quarterly》1998,37(11):962-964
A 42-year-old man, who had worked as a welder for 20 years, was admitted to our hospital complaining of a dry cough. A chest radiograph showed diffuse small nodular shadows and chest computed tomography revealed small patchy opacities. A transbronchial lung biopsy specimen showed welding fume particles mainly located in alveolar space with mild fibrosis of alveolar septa. In order to prevent further fibrosis, bronchopulmonary lavage (BPL) was performed to eliminate the fume particles. The amount of iron particles derived from the total lavage fluid was 911.7 mg. 相似文献
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124.
J Ueda S Sawaguchi T Hanyu K Yaoeda T Fukuchi H Abe H Ozawa 《Canadian Metallurgical Quarterly》1998,42(5):337-344
A combined hemostatic defect consisting of a reduction in certain procoagulants, anticoagulants (antithrombin III-ATIII-, protein C-PC-) and components of the fibrinolytic system (plasminogen-Plg-) was demonstrated in very-low-birth-weight infants (VLBW <1,500 g) with gestational age 26-32 weeks. Sixteen of them were healthy, 28 were suffering from RDS and 24 from septicemia. The hemostatic defect was more profound in the RDS group, nevertheless increased TAT (thrombin + ATIII complex) and/or PAP values (plasmin + a2-antiplasmin complex) was a more frequent finding in the septicemic group of infants (91.8 vs. 17.9%). Moderate-to-severe thrombocytopenia was detected in a higher percentage in the septicemic (70.8%) than in the RDS group (50%), and increased D-dimers were demonstrated in 34.8 and 28.6% of the infants, respectively. Elevated TAT or PAP values were not always associated with gross coagulation abnormalities, and advanced disseminated intravascular coagulation (DIC) was only documented in 16.7% of the septicemic and 7.1% of the RDS infants. None of the VLBW neonates presented with clinical evidence of thrombosis, although hemorrhagic manifestations were apparent in 34.8 and 14.3% of the neonates with septicemia or RDS, respectively, mainly due to DIC or severe thrombocytopenia. In conclusion, increased TAT and/or PAP values are good indicators of the in vivo activation of the hemostatic system, but still their impact on sick neonates morbidity and mortality remains unknown. 相似文献
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126.
T Sakuma K Takahashi N Ohya K Usuda M Handa T Abe 《Canadian Metallurgical Quarterly》1998,353(2-3):273-279
The imbalance of neutrophil elastase and alpha1-antitrypsin in pleural effusion after lobectomy and the effects of the neutrophil elastase inhibitors, sodium N-[2-[4-(2,2-Dimethylpropionyloxy)phenyl-sulfonylamino]benzo yl]aminoacetic acid (ONO-5046) and purified alpha1-antitrypsin, on neutrophil elastase activity were determined. The amount of neutrophil elastase complexed to alpha1-antitrypsin, measured by an enzyme-linked immunosorbent assay, was 170 times higher in pleural effusion than in blood 3 h after lobectomy. The alpha1-antitrypsin levels measured by laser nephelometry did not increase in either blood or pleural effusion. Although neutrophil elastase activity, measured by the hydrolysis of succinyl-(Ala)3-p-nitroanilide, was not detected in blood, it was increased in pleural effusion 3 h and 24 h after lobectomy. ONO-5046, but not alpha1-antitrypsin, reduced the neutrophil elastase activity in pleural effusion. There is an imbalance of neutrophil elastase and alpha1-antitrypsin in pleural effusion after lobectomy. ONO-5046 is a potent inhibitor of neutrophil elastase activity in human pleural effusion. 相似文献
127.
Five sulfur-containing analogues of 2,3-oxidosqualene (OS) were evaluated as inhibitors of squalene:hopene cyclase (SHC) from Alicyclobacillus acidocaldarius. In these analogues, sulfur replaces carbons at C-6, C-10, C-14, C-18, or C-19 of OS. Each analogue was a submicromolar inhibitor of SHC with IC50 values ranging from 60 to 570 nM. Enzyme inhibition kinetic analysis was performed using homogeneous recombinant A. acidocaldarius SHC. While analogues 9 (S-14, Ki = 109 nM, kinact = 0.058 min-1) and 11 (S-19, Ki = 83 nM, kinact = 0.054 min-1) were time-dependent inhibitors of SHC, analogues 7 (S-6, Ki = 127 nM) and 8 (S-10, Ki = 971 nM) showed no time dependency with SHC. Analogue 10 (S-18) was the most potent inhibitor and showed time-dependent irreversible inhibition (Ki = 31 nM, kinact = 0.071 min-1). Kinetic analysis for the five analogues with purified rat liver OSLC was conducted to compare the vertebrate and prokaryotic enzymes. Affinity labeling experiments, using either [17-3H]10 or [22-3H]10 with crude and with pure recombinant SHC, clearly showed specific labeling. A single major radioactive band at 72 kDa on SDS-PAGE indicated that irreversible covalent modification of SHC had occurred. These results suggest that the presence of sulfur at C-18 of OS can interrupt the cyclization and that an intermediate partially cyclized cation may be captured by a nucleophilic residue of the SHC active site. 相似文献
128.
H Kitagawa T Hayashi Y Mitsumoto N Koga Y Itoyama K Abe 《Canadian Metallurgical Quarterly》1998,29(7):1417-1422
BACKGROUND AND PURPOSE: Glial cell line-derived neurotrophic factor (GDNF) plays important roles in the survival and recovery of some mature neurons under pathological conditions. However, the effect of GDNF in ameliorating ischemic brain injury has not been well documented. Therefore, we investigated a possible effect of GDNF on the changes of infarct size, brain edema, DNA fragmentation, and immunoreactivities for caspases after permanent middle cerebral artery occlusion (MCAO) in rats. METHODS: For the estimation of ischemic brain injury, we calculated the infarct size of MCA region and also measured the brain water content as edema formation at 24 hours after the MCAO. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick labeling (TUNEL) staining was performed for the detection of DNA fragmentation. Immunoreactivities for caspase-1 (ICE), caspase-2 (Nedd-2), and caspase-3 (CPP32) were stained. RESULTS: Both infarct size and brain edema after permanent MCAO were significantly reduced by topical application of GDNF (48% and 30% decreases, P=0.01). TUNEL staining and immunoreactivities for caspases were markedly induced at 12 hours after permanent MCAO in the vehicle-treated animals. However, the spatial distribution of those immunohistochemically positive cells was dissociative in each caspase. Induction of TUNEL staining and immunoreactivities for caspases-1 and -3 was greatly reduced with GDNF treatment, whereas the reduction of caspase-2 staining was only minimum. CONCLUSIONS: These data suggest that the reduction of infarct size and brain edema by GDNF was greatly associated with the reduction of DNA fragmentation and apoptotic signals predominantly through caspases-1 and -3 cascades. 相似文献
129.
M Abe K Tabuchi M Goto A Uchino 《Canadian Metallurgical Quarterly》1998,38(11):746-50; discussion 750-1
Plastic skull models of seven individual patients were fabricated by stereolithography from three-dimensional data based on computed tomography bone images. Skull models were utilized for neurosurgical planning and simulation in the seven patients with cranial base lesions that were difficult to remove. Surgical approaches and areas of craniotomy were evaluated using the fabricated skull models. In preoperative simulations, hand-made models of the tumors, major vessels and nerves were placed in the skull models. Step-by-step simulation of surgical procedures was performed using actual surgical tools. The advantages of using skull models to plan and simulate cranial base surgery include a better understanding of anatomic relationships, preoperative evaluation of the proposed procedure, increased understanding by the patient and family, and improved educational experiences for residents and other medical staff. The disadvantages of using skull models include the time and cost of making the models. The skull models provide a more realistic tool that is easier to handle than computer-graphic images. Surgical simulation using models facilitates difficult cranial base surgery and may help reduce surgical complications. 相似文献
130.
High pressure oxidation of silicon was performed at an oxidation temperature range of 650 to 800°C for thin oxide films with about 300 å thickness. The index of refraction was dependent on an oxidation temperature but independent of the oxidation pressure as 1.475 at 750°C. The dielectric breakdown strength of the oxide film was measured by the voltage ramping,method. The fixed oxide charge about 1.0 × 1011 cm?2 was also measured from the high frequency C-V measurement. The pulse scanning C-V measurement technique was used to measure the minority carrier generation rate in the depleted surface. The surface generation velocity was slightly dependent on the oxidation temperature and indicated that the fast surface states increased with decreasing oxidation temperature. 相似文献