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A simple progressive exercise test was performed before and after operation on five subjects undergoing mitral valve replacement and on five subjects undergoing aortic valve replacement. The responses of heart rate and ventilation were related to work rate )kilopond metres/min). The patients were also assessed clinically by the New York Heart Association grading and radiologically before each exercise test. The clinical grading was shown to be a poor guide to observed exercise tolerance, as the improvement noted in symptoms was not matched by the objective measurement of working capacity. Only two patients had normal exercise tolerance after surgery, although six of the ten patients claimed that they had no exertional dyspnoea after operation. The changes in simple ventilatory function tests before and after operation were generally small. We suggest that measurements of exercise tolerance before and after operation should be an essential part of heart valve replacement surgery.  相似文献   
23.
Twenty-eight patients underwent open lung biopsy on an emergency basis. The clinical course in each case was deteriorating rapidly, and all were in respiratory failure. The correct diagnosis was established in 96% of the biopsies (27 of the 28 patients). The clinical diagnosis prior to biopsy was in error or incomplete in 15 (55%) of the patients. Specific therapy was lifesaving in 12 of the 28 patients. The value of the procedure outweighed the complications. Thrombocytopenia and positive end-expiratory pressure ventilation were not contraindications to biopsy.  相似文献   
24.
A retrospective record analysis of 112 juvenile-onset diabetics with nephropathy was conducted in order to determine their clinical course. The mean duration of diabetes at the onset of proteinuria was 17.3+/-6.0 years. Early renal failure appeared two years after the onset of protein-uria, and severe renal failure (mean serum creatinine level, 8.5+/-3.9 mg/100 ml) four years after the onset of proteinuria. The mean duration of life after the onset of severe renal failure was six months. The mortality was 53%, with 59% of the deaths attributable to renal failure and 36% to cardiovascular disease. All patients experienced progressive deterioration of renal function as well as the other complications of diabetes, the rate of progression being accelerated toward the end of the course. Juvenile onset diabetics should be considered for renal transplantation before the serum creatinine level reaches 8.5 mg/100 ml.  相似文献   
25.
Over the last 2 years at Metropolitan Hospital Medical Center 245 diabetic women have been seen on the obstetric service. This complication of pregnancy comprises 7.9 per cent of 3,076 deliveries, resulting in an over-all uncorrected perinatal mortality rate of 2.9 per cent. We believe that early detection and strict rigid control of diabetes is the key to improved perinatal outcome. This article presents the classification, diagnosis, and management which have led to these results.  相似文献   
26.
Two-year disease-free survival is considered highly predictive of therapeutic success with neuroblastoma and death from neuroblastoma greater than 5 years after diagnosis is a rare event. We report of an unusual case of death from neuroblastoma 20 years after diagnosis; a literature review and discussion of this rare phenomenon of late recurrence is also included. Five additional cases of late recurrence, defined as greater than 5 years after diagnosis, were found in the literature with adequate detail to be reviewed. Advanced disease was present at diagnosis in five of six cases; three of six had disseminated disease. No age or sex differences were noted. A peculiar tencency for recurrence during the teenage years, preceded by a long disease-free interval, was also present in all cases, perhaps a reflection of maturational alterations in the immune system or hormonal changes that previously had suppressed extensive disease. This phenomenon of late recurrence in neuroblastoma, albeit rare, adds another facet to the clinical behavior of an enigmatic and therapeutically unyielding childhood tumor.  相似文献   
27.
Lizards (Dipsosaurus dorsalis) were placed in a desertlike environment in which the ambient temperature (Ta) at night (1800-0600 h) was 12 degrees C and the day (0600-1800 h) Ta was between 30 and 55 degrees C depending on the location within the chamber. When dead Aeromonas hydrophila (4 X 10(9) organisms) was injected into nine lizards, an elevation in body temperature (Tb) of 2.7 degrees C was observed during the same day. On the day after bacterial injection the lizards' body temperatures averaged 41.6 degrees C, an increase of 4.2 degrees C over their control day Tb. Further investigations on the febrile response of D. dorsalis were conducted at the University of Wisconsin's Biotron, where there exists a simulated desert environment with the light intensity, temperature, and humidity closely parelleling a typical spring day in the southwestern desert of the United States (the natural habitat of Dipsosaurus). In this environment injection of dead bacteria into seven lizards led to an average febrile response of similar magnitude (Tb = 40.5 degrees C) but with a longer latency than that found at the University of Michigan. Injection of 13 lizards with live A. hydrophila (5 X 10(9) organism subcut.) in the simulated desert at Michigan led to a daytime fever averaging 2.3 degrees C (mean Tb = 40.6 degrees C) over a 5-day period. During the 6th and 7th day the lizards' body temperature returned to the normal or afebrile level. Injections of sodium salicylate along with dead A. hydrophila resulted in a dose-dependent attenuation of the febrile response. These results demonstrate that the reptilian febrile response is strikingly similar to avian and mammalian fever and suggest a common origin and perhaps function for the febrile mechanism.  相似文献   
28.
One of the principal disadvantages of the passive pill as a telemetric method for measuring various physiological parameters has been its resticted range. The reasons for the restricted range with existing detection methods are discussed. An improved method using a locking spectrometer based on third-order phase-sensitive detection is described and its performance is assessed. A significant increase in the usable range of a high sensitivity passive pill is obtained.  相似文献   
29.
On the internal or parietal surface of the left ventricle in man and in mammals are two papillary muscles, which are almost identical and well developed. In man, these muscles are known as the m. papillaris parietalis anterior sinister and the m. papillaris parietalis posterior dexter, in mammals, the m. papillaris parietalis cranialis sinister and caudalis dexter, or, in shorter form, mm. papillaris parietalis sinister et dexter. In the right ventricle in man, there are two papillary parietal muscles: the mm. papillares anteriores et posteriores. On the septum of this ventricle there is, as in mammals, a muscle called the m. papillaris septalis medialis seu subarteriosus. Beside it are one or several smaller muscles, varying from one individual to another: the mm. papillares septales accessorii seu parvi. In the right ventricle of the mammalian heart is found, in addition to the m. parietalis septalis subarteriosus, already mentioned, a m. papillaris caudalis, more or less well developed in some species and, in the majority of mammals, the m. papillaris septalis cranials, which is always well developed. In certain mammals, there is, in rare cases, a m. papillaris septomarginalis seu parietalis. It may be said, in conclusion, that, in a large number of mammals, there is, on the internal surface of the external wall of the right ventricle, a reasonably well developed m. papillaris parietalis.  相似文献   
30.
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