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81.
Favorable results of coronary artery bypass grafting in patients older than 75 years 总被引:2,自引:0,他引:2
K A Horvath V J DiSesa P S Peigh G S Couper J J Collins L H Cohn 《The Journal of thoracic and cardiovascular surgery》1990,99(1):92-5; discussion 95-6
There is controversy whether the short-term and long-term results of coronary artery bypass grafting in elderly patients justify performing the procedure. Between January 1977 and December 1986, 4580 patients underwent coronary artery bypass grafting, of whom 222 (4.9%) were 75 years old or older (mean 77 years). There were 143 men and 79 women and 139 (63%) were in New York Heart Association class IV. One hundred forty-six patients (66%) had had at least one preoperative myocardial infarction. Myocardial revascularization was performed under emergency conditions in 17 patients (18%). The mammary artery was used in 43%, 96% of the patients received two or more grafts. The mean number of bypass grafts was 3.1 per patient. The overall hospital mortality rate was 10.8% (24/222), 3.6% for elective procedures, 14.9% in urgent cases, and 35% in emergencies. In contrast, the overall early mortality rate was 3.1% in 4358 patients less than 75 years old. Complications occurred in 83 patients (37%). Of the patients discharged from the hospital, 198 were followed up for a mean of 48 months (1 to 130). Actuarial probability of survival was 75% at 48 months. Postoperatively 70% were in New York Heart Association class I or II and only 21% were rehospitalized for cardiac problems. During the follow-up period 77% of the patients were free from angina, and of those experiencing angina the mean time from operation to the first episode was 75 months. Although elderly patients have a somewhat increased operative mortality rate, particularly if operated on urgently or emergently, long-term survival and freedom from angina are excellent and justify continued performance of coronary bypass grafting in selected patients over 75 years of age. 相似文献
82.
Sharon C. Reimold M.D. Sary F. Aranki M.D. Eduardo S. Caguioa M.D. Scott D. Solomon M.D. Vladimir Birjiniuk M.D. Lawrence H. Cohn M.D. Richard T. Lee M.D. 《Journal of cardiac surgery》1994,9(3):304-313
Objectives: The purpose of this study was to determine if a device placed externally around the aortic root decreases regurgitant flow in acute aortic regurgitation. Background: Aortic regurgitant flow is dependent on central aortic pressure and the aortic root and leaflet geometry. It may be possible to decrease aortic regurgitant severity by reducing aortic root size or dimension changes. Methods: Aortic regurgitation was created in eight calf heart specimens suspended in a continuous flow system. Retrograde and antegrade aortic flow and distending aortic pressure were measured at baseline and after placement of an external aortic device at the level of the aortic annulus. In two additional specimens, the incompetent aortic valve was visualized fiberoptically before and after placement of the external device. Acute aortic regurgitation was created surgically in four live calves by excising a portion of the aortic leaflets. Antegrade and retrograde flow, left ventricular pressure, and central aortic pressure were measured at baseline, after creation of aortic regurgitation, and after placement of the external device. Results: In the in vitro calf specimens, regurgitant flow decreased from 46.9 cc/sec to 15.1 cc/sec (66.0%± 21.8% decrease) after placement of the external device (p < 0.001). The regurgitant orifice area decreased from 0.13 ± 0.04 cm2 to 0.04 ± 0.02 cm2 after device placement (p < 0.001). Antegrade flow was reduced to a smaller extent (20.0%± 19.2% decrease) by the device (p < 0.05). Placement of the device around the aorta resulted in improved coaptation of the leaflets with a marked reduction in defect size by endoscopic visualization. Use of the external aortic device was associated with improvement in aortic regurgitant severity in three of four calves with surgically created aortic regurgitation. Concluslons: In these preliminary studies, acute experimental aortic regurgitant severity is decreased by the use of an external aortic device, probably due to reduction in aortic annular dimension changes and improved aortic leaflet apposition. Further studies are needed to determine the effectiveness of this device in chronic aortic regurgitation. (J Card Surg 1994;9:304–313) 相似文献
83.
Characterization of poorly differentiated neoplasms can be a challenging task for the surgical pathologist. It is essential that the entire spectrum of immunomorphologic findings of various tumors be recognized to avoid improper characterization of a given neoplasm, which may in turn adversely affect patient management. Tumor characterization is complicated by the immunomorphologic transformations that malignant cells may undergo by virtue of which they may depart from expression of expected features and acquire new, unexpected characteristics. Traditionally, amelanotic melanomas have been difficult to characterize because of the diversity of their light microscopic morphology (epithelioid, spindle, and combined varieties). As a result, several other neoplasms are usually considered in the differential diagnosis. This report describes a primarily spindle-cell amelanotic melanoma that created a diagnostic dilemma, which could only be resolved by combining the information obtained from extensive evaluation by means of several diagnostic techniques. This case also stresses the phenotypic heterogeneity of the cytoskeleton of malignant melanomas and therefore their varied immunomorphologic characteristics. 相似文献
84.
B. M. Herbertson A. J. King J. Allen 《International journal of experimental pathology》1987,68(2):167-177
In Wistar rats a single intravascular injection of lead nitrate causes substantial cellular proliferation in the proximal tubules of the kidneys and in the epithelium of the renal pelvis, ureters and urinary bladder. The tritiated thymidine labelling index (LI) reaches a peak 18 to 24 h after injection and the mitotic index (MI) increases to a comparable extent 6 to 10 h later. The proliferation is most prominent in the bladder and proximal tubules and is virtually complete at 48 h. After a single intraperitoneal injection the proliferative changes are confined to the ureteric and bladder epithelium. In all affected tissues the proliferation develops without preceding necrosis and appears to be a hyperplastic phenomenon. After intravascular administration the volume of urine and its total protein content are significantly increased and certain proteins were detected which were not present in the urine of saline controls. 相似文献
85.
86.
W. Allen Hauser 《Epilepsia》1992,33(Z4):6-14
Summary: Age has a profound influence on our approach to the convulsive disorders. Age is a variable which is an important determinant for risk factors for epilepsy. Age, as a surrogate of brain maturation, is a determinant of the specific characteristics of the seizure disorder in those with epilepsy, and age-related changes in these manifestations can be identified. Age is a determinant for the occurrence of acute symptomatic seizures in several types of metabolic or central nervous system insults. Age is a determinant for prognosis, whether one considers remission, medication withdrawal in those entering remission, relapse following prolonged remission, or mortality. Last, age per se seems to be a risk factor for epilepsy independent of other factors. This seems particularly true for partial seizures. 相似文献
87.
Dietary protein increases urinary calcium 总被引:2,自引:0,他引:2
88.
MRI demonstration and CT correlation of the brain in patients with idiopathic intracerebral calcification 总被引:2,自引:0,他引:2
Twenty-two patients aged 36–63 years were diagnosed as having Fahr's syndrome on the basis of the presence on CT of unexpected extensive calcification of the basal ganglia. Even when associated with calcification of other brain areas, the main diagnostic criterion remained basal ganglia calcification larger than 800 mm2. Normal values of parathormone, serum calcium and phosphorus excluded hypercalcaemia and hypoparathyroidism. Mitochondrial CNS disease was excluded clinically. MRI and repeated CT and neurological examination were performed in all of the patients. The patients were divided into two groups: neurologically asymptomatic (group 1) and neurologically symptomatic (group 2). T2-weighted sequences demonstrated hyperintense areas in all of the patients involving the white and the grey matter of the brain. In group 1 the hyperintense lesions were significantly smaller than in group 2. The neurological symptoms correlated better with the hyperintensities on T2-weighted MR images than with the calcification demonstrated on CT. Hyperintensities in T2-weighted MRI and the areas shown by CT to have calcification had different locations. In 15 patients with dementia, the white matter of the entire centrum semiovale was bilaterally hyperintense. In another 3 patients with hemiparesis, hyperintense areas in the internal capsule, contralateral to the side of hemiparesis, were demonstrated in the T2-weighted sequence. The hyperintense T2 signals may reflect a slowly progressive, metabolic or inflammatory process in the brain which subsequently calcifies and are probably responsible for the neurological deficit observed. 相似文献
89.
Causes of blindness in children attending four schools for the blind in Thailand and the Philippines
Using WHO definitions of visual loss and a standardised methodology, 256 children were examined in schools for the blind in Thailand (1 school) and the Philippines (3 schools). 244 (95%) were blind (BL) or severely visually impaired (SVI). Causes of SVI and blindness were classified anatomically and aetiologically, and avoidable causes identified. Causes of visual loss in Khon Kaen, Thailand (n = 65) and Manila, Philippines, (n = 113) were similar, with conditions of the whole globe accounting for 27.7 and 27.4% of SVI/BL; retinal disease 29.2 and 23.0%; cataract 16.9 and 16.8%; corneal disease 12.3 and 13.4%; and optic nerve disease and glaucoma 6.2 and 8.8%. Perinatal factors accounted for 20.0 and 23.0% of SVI/BL; hereditary disease 13.8 and 17.7%; and 12.3 and 15.0% was due to events occurring during childhood. The underlying aetiology could not be determined in 50.8 and 41.6% of cases, respectively. In the two schools together twenty six children (15%) were blind from retinopathy of prematurity (ROP) and 16 (9%) from corneal scarring attributed to Vitamin A deficiency. 103 of 178 (58%) children had avoidable causes of visual loss. In the Filipino towns of Baguio and Davao (n = 66), the causes of visual loss were different from those in Khon Kaen and Manila, with 54.8 and 42.9% of SVI/BL being due to corneal disease, and only 3.2 and 8.5% to retinal disease. Childhood factors were more important (61.3 and 57.1%) than hereditary (9.7 and 17.1%) or perinatal factors (0 and 2.9%). Thirty one children (47%) had SVI/BL attributed to Vitamin A deficiency. No child was blind from ROP. 42 of 66 (64%) of children had avoidable causes of blindness. Overall 60% of children with SVI/BL had avoidable causes of visual loss in these 4 schools. Approximately half could have been prevented by primary health and eye care services and half could have been managed by surgical ophthalmological procedures. The causes of blindness identified in this blind school study suggest that the major causes are different for schools serving rural populations compared to those serving urban communities. Different control strategies are required for the different situations. 相似文献
90.