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81.
Much of the confusion surrounding the repair of asymptomatic abdominal aortic aneurysms relates to inaccuracies in their measurement, both preoperatively and intraoperatively. Multiple measurements of aneurysms at operation have convinced us that the largest and least variable diameter is the anteroposterior diameter measured from aortic wall anteriorly to vertebral bodies posteriorly. This APto-spine distance is accurately predicted by ultrasonography to within 0.3 cm. Computerized tomography does no better. Plain radiography is accurate but seldom applicable. When properly estimated, aneurysm size can be accurately determined preoperatively by either ultrasonography, computerized tomography, or plain radiography, in that order of preference. Since the decision to operate on asymptomatic aneurysms is based largely on their size, accurate preoperative estimation is essential.  相似文献   
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Social bonds were examined in 256 healthy, independent-living elderly men and women using the Interview Schedule for Social Interaction (ISSI). Multivariate techniques were used to test for relationships between six dimensions of social bonds, as measured by the ISSI, and demographic characteristics as well as scores from the Kellner-Sheffield Symptom Questionnaire, the Jacobs Cognitive Screening Exam, the Halstead Category Test and the Wechsler Memory Scale. The study participants reported involvement in a range of satisfying, supportive, interpersonal relationships. Significant associations were found between social bonds and income, marital status, work status and health status. Emotional status, cognitive functioning, and memory were found to be independent of social bonds in our statistical model.  相似文献   
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Fresh cardiac valvular tissues and atrial appendages removed from 106 Indian patients with rheumatic heart disease at the time of corrective cardiac surgery were examined to determine the characteristics of valvular interstitial lymphocytic infiltrates using conventional histologic staining along with indirect immunofluorescent techniques. Precise identification of the phenotypic profiles of inflammatory mononuclear cells was attempted using anti-IgG, anti-Ia, and monoclonal mouse hybridoma reagents identifying T cells (OKT3) as well as T cell subsets (OKT4 helper/inducer and OKT8 suppressor/cytotoxic cells). A similar group of 21 patients undergoing cardiac valvular resection in Albuquerque was studied. The mean age of Indian patients providing valve tissues was 27.7, whereas in those in Albuquerque, it was 52 years. Twenty-five percent of rheumatic heart valves in Indian patients showed significant interstitial lymphoid infiltrates, and one third of the rheumatic valves from patients in Albuquerque showed similar mononuclear cell collections. Lymphoid infiltrates contained a predominance of T cells (70 to 80 percent) and only occasional B cells. Most of the T cells were OKT4-positive, with only a minor representation of suppressor/cytotoxic OKT8-positive T cells. In many instances, OKT4-positive helper T cell collections were closely juxtaposed to fibroblasts and collagen fibrils. These findings suggest that the chronic rheumatic scarring process may involve helper/inducer T cells as an ancillary factor in the indolent contracture and fibrosis of deformed cardiac valvular structures. Attempts to demonstrate residual streptococcal antigens by indirect immunofluorescence using a wide panel of heterologous rabbit F(ab')2 reagents with specificity for group A streptococcal membranes, cell wall mucopeptide, or group A carbohydrate gave negative results.  相似文献   
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Five patients with interstitial nephritis who presented with a variety of clinical profiles were studied with particular emphasis on documentation of the cellular types of potentially immunocompetent lymphocytes and mononuclear cells present within interstitial renal infiltrates. Immunohistologic studies coupled with conventional light and electron microscopic observations indicated that most mononuclear cells making up renal interstitial infiltrates were T cells. Some chronic inflammatory cell foci within renal interstitium were characterized by clusters of Ia antigen-positive T cells considered to be markers for activated lymphocytes. B cells were present in very small proportions (5 percent or less). The profile of immunocompetent cells present in lesions of interstitial nephritis suggests a major role for cell-mediated immunity in this disorder. Increase in tissue lymphocytes of the Tγ subclass with receptors for the Fc portion of immunoglobulin G (IgG) also suggests local activation of intrinsic suppressor cell mechanisms.  相似文献   
86.
To assess the type and prevalence of cardiac abnormalities in heavy drinkers with and without overt congestive heart failure, M mode echocardiography was performed in 11 symptomatic chronic alcoholics with dilated (congestive) cardiomyopathy and in 22 asymptomatic chronic alcoholics. Echocardiographic data in both groups were adjusted for age and body surface area using previously derived regression equations. All 11 symptomatic patients had a significantly decreased left ventricular percent fractional shortening (mean 14 percent, normal range 28 to 44) along with significant increases in left ventricular systolic and diastolic dimensions (mean increases of 105 and 48 percent above normal, respectively), left atrial dimension (mean increase 21 percent) and estimated left ventricular mass (mean increase 105 percent). Among the 22 asymptomatic patients, 15 (68 percent) demonstrated significant increases in at least one of the following echocardiographic variables: left ventricular mass, left ventricular dimensions, septal and left ventricular wall thicknesses, and left atrial dimension. Asymptomatic patients could be classified into two subgroups: (1) those with a left ventricular diastolic dimension less than 10 percent above the normal predicted value and an increased left ventricular wall thickness to radius ratio (mean increase 16 percent above normal) and upper normal percent fractional shortening, and (2) those with a left ventricular diastolic dimension 10 to 24 percent above normal and a slightly subnormal thickness to radius ratio and lower normal percent fractional shortening. Echocardiographic abnormalities in asymptomatic chronic alcoholics did not correlate with the presence or absence of auscultatory abnormalities on physical examination and appear to reflect an earlier stage in the spectrum of alcoholic disease before the development of dilated cardiomyopathy.  相似文献   
87.
Renal handling of solute and water following oral water loading was determined in six subjects with small pituitary adenomas associated with nonsuppressible hyperprolactinemia. Compared to control subjects, urine volume and solute excretion were significantly diminished in the hyperprolactinemic group. This was attributable to a decrease in osmolar clearance. Free water clearances were not different from control subjects. Hypothyroidism and adrenal insufficiency as an explanation for the antidiuresis were excluded in each patient. The data supports the suggestion that prolactin influences renal function in man.  相似文献   
88.
This study was done to assess the adequacy of a regimen using cefazolin as a prophylactic antibiotic for patients undergoing open-heart operation. At the time of the preoperative medication, adult patients received 1 gm of cefazolin intramuscularly, and pediatric patients were given a dose of 20 mg per kilogram of body weight. Group I consisted of 10 adults undergoing a variety of cardiac procedures. The mean serum cefazolin level after institution of cardiopulmonary bypass was 27.36 μg/ml (range, 13.1 to 40.3 μg/ml). This level remained fairly stable throughout cardiopulmonary bypass. Group II consisted of 10 pediatric patients undergoing cardiac procedures for repair of a variety of congenital anomalies. The mean serum cefazolin level after institution of cardiopulmonary bypass was 20.01 μg/ml (range, 11.4 to 28.9 μg/ml) and remained stable for the duration of the procedure. In both groups perfusion pressure, urinary output, and body temperature did not seem to have any influence on these levels.It is concluded that the administration of one dose of cefazolin intramuscularly before operation results in an adequate and stable serum cefazolin level in patients undergoing cardiopulmonary bypass for up to three hours, possibly longer.  相似文献   
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