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91.
OBJECTIVE: The aim was to characterise the transmural distribution of beta adrenergic receptors in failing myocardium in cardiomyopathy. METHODS: Using a quantitative autoradiographic technique with 125I-cyanopindolol (ICYP), the density and transmural distribution of beta adrenergic receptors were compared between eight cardiomyopathic BIO 14.6 Syrian hamsters with heart failure and six normal age matched controls (BIO 14.6HAM). RESULTS: Binding of ICYP to transmural slices of hamster myocardium was rapid, saturable, stereoselective, and displaceable by antagonists. The binding isotherm showed a significant increase in the total tissue content of beta adrenergic receptors in the failing myocardium of cardiomyopathic hamsters: 15.3(SEM 1.6) fmol.mg-1 protein v 9.4(1.2) fmol.mg-1 protein in normal myocardium of control hamsters (p < 0.05). There was no difference in receptor affinity. Quantitative autoradiography showed regional heterogeneity of beta adrenergic receptors in cardiomyopathic hamsters, with an increase of beta adrenergic receptor density in the septal and subendocardial regions. In addition, the regions with increased interstitial fibrosis corresponded to the sites of increased beta adrenergic receptor density. CONCLUSIONS: The transmural distribution of beta adrenergic receptor is heterogeneous in the failing myocardium of cardiomyopathic hamsters and an increased beta adrenergic receptor density may be associated with the development of cardiomyopathy.  相似文献   
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Peptic ulcer among Japanese and Koreans in Japan has rarely been studied. In this 10-year study of hospital-based endoscopy, we focused on the epidemiology of peptic ulcer among these ethnic groups in Japan. Between 1980 and 1990, 81.2% of all patients examined via endoscopy at Saikyo Hospital in Kyoto completed a life-style questionnaire: 1,264 Japanese (70.5%), 503 Koreans (28.1%), and 25 persons of unknown ethnicity (1.4%). Characteristics of ulcer disease were almost identical for Koreans and Japanese. Like other world-wide patterns, the male to female ratio was 2.3:1. Unlike results from Western countries, however, the overall gastric ulcer rate was 1.5 times higher than for duodenal ulcer. This higher rate was due to the relatively high rate of gastric ulcer in the older age groups; among persons less than 40 years of age, duodenal ulcer was diagnosed more often than gastric ulcer. The mean age at diagnosis of duodenal ulcer (40.7 years) was significantly lower (p less than 0.005) than that for gastric ulcer (53.7 years). Multivariate-adjusted odds ratios were calculated using a multiple logistic regression model. Cigarette smoking significantly increased the risk for both gastric ulcer (odds ratio = 3.10, 95% confidence interval [CI] 2.1-4.6) and duodenal ulcer (odds ratio = 1.9, 95% CI 1.2-2.9). Age greater than or equal to 40 years (odds ratio = 2.3, 95% CI 1.6-3.3) and consumption of salty foods (odds ratio = 1.5, 95% CI 1.0-2.1) also significantly increased the risk for gastric ulcer.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
94.
To study the contribution of age to the outcome of rheumatoid arthritis (RA), 133 elderly-onset RA (ERA) patients (onset above 60-year-old) were selected out of 2164 out-patients with RA who (i) first visited the hospital within 2 years after onset of the disease, (ii) received no remission inducing drugs previously and (iii) who were treated in this hospital regularly without interruption for more than 2 years. The joint score of ERA patients between initial visit and final visit to the hospital was compared with that of matched 133 younger-onset RA (YRA) patients (onset below 60-year-old). Results indicated that, in ERA, the patients with no active joints requiring no remission inducing drugs were increased on final visit (P<0.001). Joint score at disease onset or on initial visit to the hospital was similar in the two groups, whereas joint score on final visit was significantly decreased in ERA (P=0.0001). In ERA, progression of the small joint disease and joint erosion was not accelerated, and the small joint disease was in fact decelerated as compared with YRA (P<0.0001) during initial visit and final visit. Discriminant function analysis of patients with or without no active joints on final visit reveals that joint erosion, in small joints on initial visit is a predictor of joint prognosis in ERA. The two groups were similar with regards to sex, disease duration, onset type and rheumatoid factor/antinuclear antibody positivity. Thus, older age is an independent marker of better joint prognosis of RA  相似文献   
95.
Hepatic resection under in situ hypothermic hepatic perfusion   总被引:2,自引:0,他引:2  
BACKGROUND/AIMS: Temporary inflow occlusion of the portal triad has been used frequently in hepatectomy to minimize bleeding. On the other hand, Pringle's maneuver produces ischemic-reperfusion injury especially in patients with underlying liver disease. METHODOLOGY: Thirty-seven cases of hepatic resections were performed with intermittent Pringle's maneuver (IP group; n = 17) and in situ hypothermic perfusion (CP group; n = 20). In the CP group, hepatic inflow was continuously occluded, and 4-degree Centigrade Ringer's lactate was administered by drip during resection. Hepatic outflow occlusion was not performed. RESULTS: All patients tolerated the procedures well. Cold perfusion technique significantly decreased both the times required and the blood loss in hepatectomy (p < 0.05). Serum hyaluronic acid levels gradually increased after the induction of hepatectomy and peaked 10 minutes after reperfusion in the both groups. Thereafter, it decreased and showed a significantly lower level in the CP group until 60 minutes after reperfusion (p < 0.05). Hepaplastin levels remained significantly higher in the CP group one week after operation (p < 0.05). CONCLUSIONS: Using the technique of in situ hypothermic perfusion, we can prolong the ischemic time safely with minimal systemic influence even in cases with underlying liver diseases. This may compare favorably with intermittent Pringle's maneuver in terms of reducing hepatic sinusoidal endothelial cell damage during hepatectomy and reperfusion.  相似文献   
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97.
A simplified direct radioimmunoassay for urinary acid labile aldosterone was developed. One ml of urine was hydrolysed with 2 ml of 0.2N HCL at 30 degrees C for 16hrs. One tenth ml of hydrolysed urine diluted 10 times with charcoal treated aldosterone-free calf serum was used for the radioimmunoassay. The radioimmunoasssay was done with a specific antibody, 125I-aldosterone, as the labeled antigen and polyethylene glycol for bound-free separation. There were excellent correlations between the present methods and other methods, i.e., i) a method using dichloromethane extraction before the assay as well as pre-extraction before hydrolysis and ii) a commercial kit using 3H-aldosterone. The intra-assay coefficient of variation was 5.8%, and the inter-assay coefficient of variation was 9.5%. The normal value of urinary aldosterone was excretion was 3.7 plus or minus 2.5 micrograms/day by the present method, and values of patients with primary aldosteronism were between 24 to 43 micrograms/day.  相似文献   
98.
The specificity of exercise thallium-201 emission computed tomography for coronary artery disease was assessed in patients with intraventricular conduction disturbances. Eighty-seven patients were studied: 33 with right bundle branch block (RBBB), 11 with RBBB and left-axis deviation, 11 with left (L)BBB, 12 on right ventricular pacing, and 20 with Wolff-Parkinson-White (WPW) syndrome. A control group of 349 consecutive patients with normal intraventricular conduction was also examined. The specificity of diagnosis of coronary artery disease in patients with LBBB (30%), right ventricular pacing (44%) or RBBB plus left-axis deviation (50%) was significantly lower than in patients with normal intraventricular conduction (94%; p less than 0.01). In contrast, there was no significant difference between specificity in patients with RBBB (86%) or WPW syndrome (90%) and patients with normal intraventricular conduction. Perfusion defects were found in the anterior, septal and inferior segments in patients with LBBB, and in the septal and inferior segments in patients with RBBB plus left-axis deviation despite the absence of coronary stenosis. Furthermore, diffuse slow washout was seen more often in patients with WPW syndrome (35%) than in controls who had normal intraventricular conduction (11%; p less than 0.05), despite a good exercise performance in the former group. This study suggests that there is an increased incidence of abnormal perfusion and clearance during exercise thallium-201 emission computed tomography in patients with intraventricular conduction disturbances.  相似文献   
99.
Summary To assess left ventricular diastolic properties in response to dynamic exercise, mitral inflow velocity integrals were measured by pulsed-wave Doppler echocardiography in ten patients with myocardial infarction and in ten normal subjects, and simultaneous left ventricular pressure was obtained with micromanometry in the patients. Early filling velocity integrals were maintained in the patients during exercise. Late filling velocity integrals were not augmented during exercise in the patients, but were increased in the normal subjects. In the patients, there was an increase in mitral valve opening pressure, left ventricular end-diastolic pressure, and the time constant of left ventricular isovolumic pressure decay. The lowest diastolic pressure and the number of time constants that had elapsed before the lowest diastolic pressure remained unchanged. These results show that in patients with myocardial infarction, early filling is maintained by an increase in driving pressure during exercise, despite incomplete relaxation. Augmentation of late filling, seen in normal subjects, is impaired in patients with myocardial infarction, probably due to an increase in left ventricular stiffness.  相似文献   
100.
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