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During a 12-month period 115 patients with abnormal mammograms had stereotaxic needle localization and biopsy of nonpalpable breast lesions. The procedure was performed on a Fischer Mammotest II machine (Fischer Imaging; Denver, CO) and the biopsies were taken with a #18 gauge Bard biopsy needle using a Bard biopty gun (distributed by Bard Urological; Covington, GA; manufactured by Radiplast; Uppsala, Sweden). Mammographic lesions were suspicious matrix densities (85), clustered microcalcifications (22), or a combination of both (8). The pathologist recommended open biopsy in 16 per cent (18/115) of the patients. Pathology on the 18 open biopsies revealed that 11 (9 matrix densities and 2 calcifications) were carcinomas and true positives, whereas the other 7 (all matrix densities) were benign mastopathies and false positives. Further analysis of the pathologic data showed that there were three possible diagnoses from the needle biopsies on the patients that later went to open biopsy: cancer (6), very suspicious lesion (9), and slightly suspicious lesion without atypical hyperplasia (3). All 6 cancers were confirmed by open biopsy; about half (5/9) of the very suspicious lesions were cancer and none (0/3) of the slightly suspicious lesions were cancer. More cases, followed by open biopsy, are needed to refine the selection procedure for open biopsy and careful follow-up of the patients who did not have open biopsy will also be needed to determine the false negative rate. Excellent patient acceptance was found and the test was easy to perform in the office without serious complications. Furthermore, the test was cost effective because it avoided open biopsy in 97 patients.  相似文献   
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感应式人工耳蜗装置将声音信息转变并处理为适当的电信号之后,采用电磁感应的方式将此信号送至植入全聋患者内耳耳蜗靠近听神经纤维的作用电极上,刺激神经发放冲动,使全聋患者恢复音感。本装置经临床全聋患者使用,取得较满意效果。  相似文献   
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Parastomal hernia in relation to site of the abdominal stoma   总被引:13,自引:0,他引:13  
Parastomal hernia is a common late complication of enterostomy, especially colostomy, and sometimes requires surgical treatment. A possible contributory factor, location of the stoma in relation to the rectus abdominis muscle, was studied by examination of 130 patients with permanent intestinal stoma. The bowel had been brought out through the rectus abdominis muscle in 107 patients and lateral to it in 23 patients. The respective prevalence of parastomal hernia in these groups was 2.8 per cent and 21.6 per cent. The highly significant difference indicates that enterostomy should be constructed through the rectus abdominis muscle, not lateral to it.  相似文献   
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BACKGROUND AND PURPOSE: The strength of the association between blood pressure and stroke incidence is dependent on the number of blood pressure measurements. Different summary variables of repeated blood pressure measurements taken during 10 years were evaluated in relation to the long-term risk of stroke in the Zutphen Study. METHODS: During the period 1960-1970 repeated blood pressure measures were taken yearly in 603 men aged 50-69 years in 1970 in the town of Zutphen, The Netherlands. The individual average systolic blood pressure between 1960 and 1970, the predicted systolic blood pressure for 1970 (based on regression of blood pressure readings on time), and the single observed systolic blood pressure in 1970 were used as systolic blood pressure estimates. Their strength in predicting the 15-year stroke incidence was assessed using Cox proportional hazards models. Adjustment was made for the confounding effects of age, cigarette smoking, and serum total cholesterol. RESULTS: The average systolic blood pressure between 1960 and 1970 was the strongest predictor of 15-year stroke incidence. The strength of the association was underestimated by 55% when a casual systolic blood pressure measurement was used instead of 11 yearly measurements. CONCLUSIONS: It can be concluded that a casual blood pressure measurement leads to a substantial underestimation of the long-term stroke risk of an individual.  相似文献   
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A thermal manikin of the size of a 1 kg premature baby has been constructed. The nonevaporative heat loss from eight different regions and the total heat loss were measured. The measurements of heat loss have high repeatability and the values are in good agreement with measurements of dry heat loss for premature babies, using indirect calorimetry. The heat losses from the manikin in a single-walled, air-heated incubator and on a recently described heated, water-filled mattress have been compared. The total heat loss was found to be 20 to 30 W/m2 with both methods at ambient temperatures between 15 degrees and 25 degrees C. Treatment on a heated, water-filled mattress provides a means of direct conductive heat input to the baby, with a conductive heat transfer coefficient of 0.4 W/degrees C or 21 W/m2 degrees C. The thermal manikin appears to provide an accurate method for assessment of the thermal conditions in neonatal care.  相似文献   
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We used previously characterized murine monoclonal antibodies to develop a panel useful in subtyping Venezuelan equine encephalitis (VEE) viruses by an indirect fluorescent antibody assay. This panel worked well with either prototype VEE viruses or a series of more recent VEE virus isolates. The panel is particularly useful for rapidly differentiating VEE viruses with epidemic-epizootic potential from other endemic varieties of this virus. Using this panel, we identified an antigenic variant of prototype VEE subtype 1E virus currently present in Mexico. This antigenic change in the E2 glycoprotein was confirmed by enzyme-linked immunosorbent assay. Because VEE virus virulence has been associated in part with the E2 glycoprotein, this observed antigenic change in the 1E virus E2 glycoprotein may explain the apparent equine virulence of this unusual VEE 1E virus.  相似文献   
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The physiopathology of combined volvulus of sigmoid and small intestine is discussed. In many cases a half-knot is involved, that is to say a "key" between the two ileal and sigmoid loops, difficult to describe with words but easy to understand by the use of a diagram and radiologic and intraoperative images of lesions, of possible assistance when releasing the loops or determining site of section of foot of occluded loops. Of 116 cases of sigmoid volvulus treated in the Treihville hospital, Abidjan between 1972 and 1983, eleven were associated with small intestine volvulus. Of these 11 cases, 9 were treated by emergency ideal colectomy and small intestine resection, with 3 deaths, and 2 by emergency ideal colectomy and small intestine reintegration, with 2 deaths. Operative mortality was therefore high (45%), global mortality being 24%. This is inherent in underdeveloped surgical units and will certainly improve greatly as hospital standing improves.  相似文献   
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