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The effects of potassium in reperfusion solution (RS) and the influence of sodium on this effect were studied. Experimental time course was as followed: 20 min working perfusion, 3 min cardioplegic infusion with St. Thomas Cardioplegic Solution followed by global ischemia for 33 or 35 min at 37.5 degrees C, 15 min early Langendorff reperfusion with several different potassium concentration modified with Krebs Henseleit Bicarbonate Buffer (KHBB) containing 145 mM and 110 mM sodium and 5 min late reperfusion with KHBB, followed by 20 min working perfusion. Potassium in RS possessed bell shaped dose response nature with optimal concentration of 10 mM in the condition of 145 mM sodium but 6 m in the condition of 110 mM in terms of percent recovery of aortic flow. Although higher potassium reperfusion produced less Creatine Kinase leakage.  相似文献   
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To determine the clinical recommended dosage regimen of risedronate for the treatment of involutional osteoporosis in Japanese patients, dose-response relationships for the efficacy and safety of this drug were investigated using a multi-center, randomized, double-blind, parallel group comparative design with four dose levels of risedronate (placebo, 1 mg, 2.5 mg and 5 mg per day). A total of 211 patients diagnosed with involutional osteoporosis according to the criteria proposed by the Japanese Society for Bone and Mineral Research were randomized and received one of the four doses once daily for 36 weeks. All patients were supplemented with 200 mg of calcium daily in the form of calcium lactate. The primary efficacy endpoint was the percent change in bone mineral density of the lumbar spine (L2-L4 BMD) determined by dual-energy X-ray absorptiometry (DXA) from baseline to the time of final evaluation. Changes in biochemical markers of bone turnover and safety profile were also compared. Percent changes in L2-L4 BMD at final evaluation in the placebo, and 1-, 2.5-, and 5-mg risedronate groups were 0.79+/-5.30, 2.71+/-4.93, 5.29+/-3.96, and 5.15+/-4.25% (mean+/-SD), respectively. A linear dose-response relationship was obtained up to a dose of 2.5 mg, whereas no further increase in BMD was observed at 5 mg. The decrease in bone turnover markers, including N-terminal osteocalcin, phosphorus, and urinary deoxypyridinoline, also showed a linear dose-response relationship up to a dose of 2.5 mg. Alkaline phosphatase level decreased linearly up to a dose of 5 mg. Risedronate was well tolerated in this 36-week study with 1- to 5-mg doses. Neither the overall incidence of adverse events nor the percentage of patients without problem in overall safety assessment differed significantly among the dose groups including the placebo group. Based on these results, a once-daily dose of 2.5 mg of risedronate, which is half that used in Caucasians, is recommended for the treatment of involutional osteoporosis in Japanese patients.  相似文献   
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Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device.  相似文献   
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We have investigated the clinical significance of urinary tissue polypeptide antigen (TPA) as a tumor marker for urothelial cancers. Urinary TPA levels were determined by the immunoradiometric assay of Prolifigen TPA Kit "Daiichi"-II in 486 healthy controls and 1835 patients with various diseases including 526 with urothelial cancers and 140 with prostatic cancer. The mean value of urinary TPA was 199 +/- 213 (1SD)U/1 in 486 healthy controls. 95% of them having a level below 600 U/l. Therefore, 600 U/l was applied as a cut-off level. Positive rates of urothelial cancers and reactivated prostatic cancer were 57.6% (148 of 248 cases) and 45.5% (5 of 11 cases) respectively. On the other hand, the false positive rate of most urological benign diseases was only about 20% except for the acute stage of urinary tract infections and upper urinary tract stones with hydronephrosis. There was no significant difference in the positive rate between urinary TPA level and urinary cytology in urothelial cancers. The combination of both tests raised the positive rate to 73.1%. Therefore, urinary TPA may be useful in the monitoring of urothelial cancers, and the combination of urinary TPA and urinary cytology may increase the diagnostic accuracy.  相似文献   
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