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101.
The purpose of this study was to develop an isolated, pulsatile blood-perfused rat lung model that allows us to evaluate the preserved lung functions. Lungs isolated from Sprague-Dawley rats, were perfused with venous whole blood by either a pulsatile or constant flow. The effuent was continuously deoxygenated with a 95% N2/5% CO2 gas mixture. Airway resistance, lung compliance, elastic work, flow resistive work, pulmonary vascular resistance, and blood gas analysis were assessed. Pressor responses toN G -monomethyl-l-arginine (l-NMMA) were compared between pulsatile and constant blood flow. At a flow of 0.1 ml/g body weight/min, pulsatile perfusion allowed for stable perfusion at least for 2h (mean 162.5±15.1 min) with stable aerodynamic and hemodynamic variables including blood gas tensions, whereas constant perfusion resulted in immediate lung failure. Whenl-NMMA was added to the perfusate, the mean pulmonary artery pressure did not show any change in the constant flow (6.0±2.6% increase), but did show a significant increase in the pulsatile flow (45±11% increase). Pulsatile blood flow reduced the pulmonary vascular resistance relative to the constant flow and allowed for a 2-h perfusion period to evaluate the lung function. The vasorelaxant mechanism in the pulsatile perfusion is related in part to the endothelial-dependent relaxation observed in the nitric oxide pathway. Presented in part at the 79th, Annual Clinical Congress of the American College of Surgeons (ACS) held in San Francisco, CA USA, 1993.  相似文献   
102.
The structure of a new antitumor antibiotic SF2575, has been determined by spectroscopic analyses of the antibiotic and its alkaline degradation products. The relative stereochemistry has been confirmed by X-ray crystallographic analysis. The antibiotic has a 2-naphthacenecarboxamide carbon skelton which is structurally related to the tetracycline antibiotics and it is unique by bearing C-glycoside, salicyclic acid and angelic acid moieties.  相似文献   
103.
A case of 'low tension glaucoma' with primary empty sella is reported. The visual field defect and optic disc change were characteristic of glaucoma. The intraocular pressure was within normal limits. X-ray examination and the metrizamide-CF procedures revealed a primary empty sella. The coexistence of 'low tension glaucoma' and empty sella is discussed.  相似文献   
104.
105.
The diagnostic value of cine magnetic resonance imaging (cine-MRI) was evaluated in 10 patients with disease of great vessels. The parameters necessary to decide the appropriate treatment, such as presence and extension of intimal flap, DeBakey type classification, identification of the entry, differentiation between true and false lumen, and between thrombosis and slow flow were demonstrated in all patients with dissecting aortic aneurysm. However, abdominal aortic branches could not be demonstrated enough by cine-MRI, therefore conventional AOG was necessary to choose the operative procedure in these cases. In patients with thoracic aortic aneurysm (TAA), cine-MRI was valuable in demonstrating both blood flow and thrombus in the lumen of aneurysm, and AOG was thought to be unnecessary in most cases. Cine-MRI is a promising new technique for the evaluation of diseases of great vessels.  相似文献   
106.
107.
It has been known that clarithromycin (TE-031, A-56268), a new macrolide antibiotic (ML), achieves higher concentrations in blood, is better excreted into urine and is better distributed into various tissues than conventional MLs. We investigated the pharmacokinetics of TE-031 in children upon oral administration of the drug in the following method. TE-031 granular preparation with a potency of 100 mg/g was given to 6 boys (5 years 4 months-14 years 0 month) with dose levels of 5 mg/kg and 10 mg/kg for each 3 boys. A tablet preparation with each tablet containing 50 mg of TE-031 was administered to 4 boys and 2 girls (8 years 5 months-11 years 6 months) with dose level of 2 tablets (i.e., 100 mg) and 3 tablets (i.e., 150 mg) for each 3 children. All administrations were done at 30 minutes before meal. Then, to conduct a cross-over test, the granule preparation was given orally to the 3 children mentioned above who was given 2 tablets and the 1 of 3 cases that were given 3 tablets at the same dose levels (100 mg and 150 mg) respectively. A bioassay was used to determine concentrations in blood of active antibiotic compounds and an high performance liquid chromatography (HPLC) was used to determine unchanged TE-031 and its main metabolite, M-5. Urinary concentrations of active antibiotic compounds were also determined by the bioassay and the HPLC was used to determine concentrations and proportions of unchanged TE-031 and its metabolites, M-1, M-4, M-5, M-6 and M-7 to figure out the urinary recovery rate in the first 6 hours. The results of these experiments are summarized as follows. 1. As was mentioned above, TE-031 was administered orally to 2 groups of children at dose levels of 5 mg/kg and 10 mg/kg, respectively. Mean serum levels of total active antibiotic compounds reached their maximum in 1 and 2 hours for the 5 mg/kg and the 10 mg/kg dosage groups, respectively, at 1.28 and 3.62 micrograms/ml, respectively. Mean half lives of serum concentrations in the 2 groups were quite similar, with values of at 2.1 and 2.0 hours, respectively. Mean serum concentrations of unchanged TE-031 determined by the HPLC method reached their peaks in 1 hour after administration in either of the 5 and 10 mg/kg dosage groups at peak levels of 0.65 micrograms/ml and 2.67 micrograms/ml, respectively. Thus, dose-response relationships were observed with TE-031 and M-5.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
108.
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997)  相似文献   
109.
Abstract This study was designed to investigate the effects of differences in the route of nutritional support of the donor on cold ischemia/reperfusion injury. Participation of Kupffer cells in these effects, based on the analysis of hepatic energy metabolism in early phases of reperfusion was also investigated. Orthotopic liver transplantation was performed between Large-White pigs weighing 20–30 kg after a 4-h cold preservation of the graft in Euro-Collins solution at 4°C. One group was fed orally with a standard laboratory diet (FED group, n = 5), a second group was fasted and given 20% glucose intravenously (12 kJ/kg per day) (PEF group, n = 5), and a third group was fed orally with a standard laboratory diet and given GdCI3 (10 mg/kg) intravenously 24 h before operation (FEDGD group, n = 5). These treatments were given for 7 days prior to harvesting. The survival time was significantly longer in the PEF (34.8 ± 5.5 days) and FEDGD (28.0 ± 11.9 days) groups than in the FED (9.8 ± 2.0 days) group ( P < 0.05). The serum hyaluronic acid elimination rate determined from 1 to 2 h after reperfusion was significantly lower in the FED group than in the other two groups ( P < 0.001). The glycogen content of the livers 1 h after reperfusion in all three groups had been consumed rapidly, but the ATP content of the livers was significantly reduced in the FED group alone ( P < 0.01). Hepatic FFA clearance (CFFA) was moderately increased in all three groups in the early phase after reperfusion, but it was higher in the FED group than in the other two groups, with significant differences 1 and 2 h after reperfusion ( P < 0.05). In conclusion, parenteral nutrition of the donors reduced cold ischemia/reperfusion injury which is related to Kupffer cell activation and, thus, was better than enteral nutrition for donor management.  相似文献   
110.
Calcified stenotic aortic valve are usually replaced by the artificial valve. Recently, we are trying to decalcify the calcification of the aortic valve by ultrasonic energy. This case report reviewed a small physique, 47 year old female, who had the calcified stenotic bicuspid aortic valve and the narrow aortic valve ring (18 mm diameter). The ultrasonic decalcification was performed by the ultrasonic surgical instrument, SUS-201D (ALOKA), ultrasonic energy output range from 25% to 45%. After the ultrasonic decalcification, the movability of the aortic cusps were improved and the aortic opening was enlarged. The systolic pressure gradient across the aortic valve was improved from 100 mmHg to 20 mmHg. This method "ultrasonic decalcification" is very useful technique for the repair of the calcified aortic valve stenosis.  相似文献   
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