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51.
Moiré interferometry was used for direct measurements of the crack tip behavior in the homogeneous compact tension (CT) specimens of A533B and HT80 steels, and in electron-beam welded inhomogeneous CT specimens of the two materials. These two materials have considerably different yield stresses, although their elastic properties are the same. Five types of homogeneous and inhomogeneous specimens were used in the experiment. Moiré fringe patterns of the five specimen types were directly compared for elastic, elastic-plastic and unloaded stages. Although the global deformations in terms of the load versus COD relations exhibit little inhomogeneity effects, large inhomogeneity effects were observed in the moiré fringe patterns in the elastic-plastic and unloaded stages. The near-tip deformations were also compared with the corresponding HRR singular fields. In a horizontal weld specimen, due to strong hardening in the weld region, the slope of the displacement field does not shift the characteristic HRR field for the A533B or the HT80 steel for increasing load.  相似文献   
52.
A 71-year-old man was admitted to our hospital with massive GI bleeding and followed by acute myocardial infarction. Severe three vessel coronary artery disease with poor left ventricular performance (EF: 40%) was demonstrated by coronary angiography. He was referred for CABG. He had also cholecystitis, which needed surgical treatment simultaneously. Combined CABG and cholecystectomy were performed without using gastroepiploic artery as a bypass graft, and through separate median sternotomy and through right upper transrectal laparotomy. Postoperative course was uneventful. This combined procedure is beneficial for the patients with acute cholecystitis and unstable angina.  相似文献   
53.
OBJECTIVE: To test stability of insulin lispro in two insulin infusion systems over 48 h. RESEARCH DESIGN AND METHODS: We used reverse-phase and size-exclusion high-performance liquid chromatography (HPLC) to determine the purity, potency, and degree of polymerization of U100 insulin lispro (Humalog) after 24- and 48-h pump cycles conducted at 37 degrees C in five Disetronic H-TRON V100 and five MiniMed 504 pumps. Pumps were set to deliver a basal rate of 0.5 U/h and 6-U boluses at t = 0, 4, 8, 24, 24.5, 28.5, 32.5, and 48 h during each cycle. The effluent was collected into 1-ml vials, pooled at 24 or 48 h, and stored at 4 degrees C until assay. After each 48-h run period of insulin delivery, assays for potency, polymer, and purity were performed on the pooled samples from each individual cycle. m-cresol content and the pooled reservoir content were assayed in the 48-h pooled samples. RESULTS: Insulin lispro retained full HPLC potency (delta < or = 4%) at 48 h, with no degradation of insulin lispro to des-amidoinsulin forms (24 or 48 h). No increase in pumped insulin polymer concentration was observed following 24 h of pump flow. Nonsignificant increases of < or =0.09% (Disetronic) and < or =0.15% (MiniMed) from initial concentrations of 0.18% (polymer divided by total insulin) were detected in three of five pump cycles at 48 h when compared with 37 degrees C paired controls. Nonsignificant decreases (<5 and 10%, Disetronic and MiniMed, respectively) of m-cresol content occurred in both systems following 48 h storage in each device, but sterility was not compromised by this decrease (initial m-cresol concentration, 3.15 mg/ml). Pump performance was without mechanical or electrical fault throughout the study Basal and bolus insulin delivery was evaluated three times daily and remained as expected. Occlusion of catheters by insulin precipitation did not occur, and no change in pH was observed following delivery. CONCLUSIONS: We conclude that insulin lispro is suitable for prolonged infusion in these two medical devices when syringes and catheters are replaced at 48-h intervals.  相似文献   
54.
Accurate measurements of the total number of muons in an air shower are important for the discrimination of showers produced by astronomical gamma rays from those produced by protons. In order to perform this discrimination, muon detectors with a total area of about 400 m2 have been constructed in the Ohya stone mine. At ground level, scintillation detectors have been distributed for determining the total number of electrons in the air shower. The arrival direction of the air shower determined by usual timing information was examined using independent data on the arrival direction determined by muons in the shower. The angular resolution thus obtained at the shower maximum is 1.7° in the south-north plane and 2° in the east-west plane. The difference of the resolution is due to the asymmetric arrangement of scintillation detectors.  相似文献   
55.
Our purpose was to evaluate the hemodynamic effects of olprinone hydrochloride early after coronary artery bypass grafting (CABG). Fifteen patients undergoing CABG were administered a constant infusion of 0.1 microgram/kg/min of olprinone and continued for 4 hours. No bolus infusion of olprinone was administered before continuous infusion. Systolic systemic arterial pressure, systolic pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance were significantly decreased. There were no significant changes in heart rate, mean central venous pressure, mean left atrial pressure and left ventricular stroke work index. Cardiac index was significantly increased, but a correlation between cardiac index and mixed venous blood oxygen saturation was not found. Double product was significantly decreased, which described above suggest that olprinone achieved improvement of left cardiac function without more myocardial oxygen consumption. Severe transient hypotension (systolic arterial pressure < 80 mmHg) after infusion of olprinone was observed in three patients. Olprinone administered soon after CABG surgery had beneficial effects in terms of improvement of hemodynamic status without more oxygen consumption and reduction of pulmonary vascular resistance. However transient hypotension was a serious clinical problem in patients after open heart surgery, especially in CABG patients who need suitable systolic arterial pressure to keep enough blood perfusion of arterial bypass grafts.  相似文献   
56.
The determinations of cardiac troponin T provide the highest diagnostic efficiency for the detection of myocardial cell necrosis. To assess perioperative myocardial infarction, serum levels of cardiac troponin T were determined in 14 patients undergoing coronary artery bypass grafting (CABG). The patients were divided into two groups: group I (n = 9), those whose troponin T was less than 1.00 ng/ml on the first postoperative day; group II (n = 5), those whose troponin T was more than 1.00 ng/ml on the first postoperative day. Troponin T levels in group II patients were significantly higher than in group I from the second to the seventh postoperative day. Two patients in group II had specific changes on the electrocardiogram detecting perioperative myocardial infarction as a new Q wave and R wave reduction. These results suggest that troponin T is a valuable marker of perioperative myocardial infarction following CABG.  相似文献   
57.
Several carboxylic acids were adsorbed on the surface of lead titanate. The total amount of adsorbed acid was determined and characterized by diffuse reflectance infrared Fourier transmission spectroscopy (DRIFTS). The acids were found to be chemisorbed on the lead titanate surface by a metal carboxylate bond. This bond forms by reaction between surface hydroxyls and the organic acid functional group. The amount of adsorbed species per unit surface area varied with each carboxylic acid studied and generally correlated with the size of the individual molecules. The experiments also demonstrate an application of a sensitive method for carbon analysis, oxygen-based coulombic titration.  相似文献   
58.
59.
PURPOSE: We correlated the expression of bcl-2 with accumulation of p53 protein in bone marrow metastases from patients with androgen independent prostate cancer and a history of hormonal ablation therapy. These results were correlated with clinical parameters, including the extent of bone marrow metastases and patient survival. MATERIALS AND METHODS: All 43 patients studied had evidence of prostate cancer progression following androgen deprivation therapy and histologically confirmed bone marrow metastases. Decalcified tissue sections were used for immunohistochemical evaluation of bcl-2 protein and p53 protein accumulation. RESULTS: We previously established that p53 protein accumulation as detected by immunohistochemistry is a reliable indicator of p53 gene mutation in prostate cancer. Immunoreactivity was demonstrated for p53 protein in 22 of 43 cases and for bcl-2 protein in 14. A total of 28 cases (65%) exhibited immunohistochemical evidence of p53 and/or bcl-2 expression, and 15 (35%) were negative for p53 and bcl-2. The expression of bcl-2 and accumulation of p53 were independent events (p < 0.01). The expression of bcl-2 or accumulation of p53 protein in prostate cancer metastases did not significantly influence patient survival or the extent of metastatic disease. CONCLUSIONS: The presence or absence of p53 protein accumulation and/or bcl-2 expression did not correlate with tumor burden or patient survival in stage D androgen independent prostate cancer bone marrow metastases. The expression of bcl-2 protein occurs independently of and is inversely correlated with p53 mutations in advanced prostate cancer.  相似文献   
60.
The structure of an asymmetrically expanded optical field normal to the active layer was applied to 1020-nm ridge waveguide laser diodes in order to increase their maximum kink-free output power and reduce the aspect ratio of the output beams. As a result, a kink-free output power of more than 400 mW and an aspect ratio of less than 2.5 were achieved by this structure. Good reliability was also obtained at an output power of 300 mW at 50/spl deg/C.  相似文献   
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