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991.
992.
Objective: Abnormal right ventricular function in patients with pulmonary heart disease (PHD) may contribute to their reduced exercise capacity. We have evaluated the effect of subacute dosing with xamoterol, a beta-1 adrenoreceptor partial agonist with inotropic properties, on right ventricular function in patients with PHD. Patients: Twelve patients with advanced chronic obstructive pulmonary disease and clinical evidence of PHD received xamoterol 200 mg twice daily or placebo for 7 days in a randomised double-blind crossover study. Right heart krypton-81m radionuclide ventriculography was used to derive right ventricular ejection fraction (RVEF) both at rest and during submaximal exercise, and indices of right ventricular systolic and diastolic function at rest. Results: During treatment with placebo, mean RVEF was 0.53 at rest and was unchanged during exercise. After xamoterol, mean RVEF was 0.55 at rest and increased to 0.59 during exercise. Xamoterol increased right ventricular peak ejection rate from 3.04 to 3.45 EDV⋅s–1 and mean early diastolic filling rate from 1.00 to 1.20 EDV⋅s–1. Conclusion: Subacute treatment with xamoterol in patients with PHD improves right ventricular systolic and diastolic function at rest and results in a favourable augmentation in right ventricular function during submaximal exercise. Received: 7 July 1995/Accepted in revised form: 9 October 1995  相似文献   
993.
994.
Distribution of antigens reactive with rabbit antirat thymic cell serum   总被引:1,自引:0,他引:1  
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995.
Abstract. There is marked alteration in endocrine activity during acute myocardial infarction (AMI). Many of the hormones involved act by changing target cell concentrations of adenosine 3': 5' monophosphate (cyclic AMP). Since cyclic AMP can escape from cells, changes in intracellular concentrations of the nucleotide may be reflected in changes in plasma levels. The purpose of this study was to determine whether plasma cyclic AMP concentrations alter during the development of AMI.–Elevation of plasma cyclic AMP concentrations was noted during the first few hours following the onset of symptoms of AMI. The highest concentrations, recorded in a group of four patients with shock, showed a range of 54–193 pmol/ml which was significantly elevated compared to the normal range of 9–22 pmol/ml. This increase in plasma cyclic AMP correlated significantly and positively with plasma concentrations of total catecholamines. Patients with the worst prognosis had the highest plasma concentrations of cyclic AMP and total catecholamines.  相似文献   
996.
997.
Six generations of ill-used children in a Huntington's pedigree   总被引:1,自引:0,他引:1  
This Huntington''s pedigree of six generations illustrates the interaction of environmental and genetic factors causing prolonged suffering to children reared in such families.  相似文献   
998.
In an attempt to define the true frequency of multiple primary squamouscell carcinomas of the upper aerodigestive tract, 3 separate population groups were studied. The results of this investigation confirmed the high incidence of multicentric carcinomas in the upper aerodigestive tract, lung, and esophagus. The clinical significance of this phenomenon is discussed, particularly its effect on patient survival and its possible relationship to local tumor recurrence. The value of routine panendoscopy in the initial assessment is stressed as well as the need for a lifelong follow-up of these patients.  相似文献   
999.
1000.
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