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981.
The accuracy of detecting and assessing the nature of deep seated non-palpable lesions by ultrasonically guided biopsy has not been well established. Although various authors have reported the accuracy of this technique in large mass lesions1,2 the accuracy in non-palpable lesions has not been emphasized. A real-time sector scanner with a biopsy guide attached to a 3 MHz transducer was used for guiding 23 gauge fine needles into 24 patients with deep seated non-palpable masses, detected on ultrasound studies, with a view to diagnose or exclude malignancy, and to establish the exact nature of these lesions, either benign or malignant. Aspiration biopsy accurately diagnosed the lesions in 18 patients (75%). No complications occurred in any case.  相似文献   
982.
Balloon dilation catheters were used to treat 94 gastrointestinal strictures in 92 patients over a 6-year period. Long-term follow-up data were obtained for 80 of these patients, with a mean follow-up period of 389 days. Overall, of the patients who underwent a successful dilation procedure, 83% remained symptom free after 1 year, and 69% after 2 years. The location of the stricture did not significantly influence the long-term outcome, nor did procedure characteristics, aside from primary technical failure. Both patients with malignant strictures and those whose strictures were associated with an anastomosis were more likely than other patients to have recurrent symptoms.  相似文献   
983.
Accessory breast tissue in the axilla: mammographic appearance   总被引:2,自引:0,他引:2  
Adler  DD; Rebner  M; Pennes  DR 《Radiology》1987,163(3):709-711
Mammographic features of normal accessory axillary breast tissue were analyzed in 13 women, 54% of whom had positive findings on physical examination. Radiographically the accessory tissue resembled the remaining normal glandular tissue but was separate from it. The mean radiographic dimension of the accessory tissue, which was best seen on oblique or exaggerated craniocaudal views, was 3.9 cm. In most cases the accessory tissue was either bilateral or confined to the right side. When found on mammography, accessory axillary breast tissue should be recognized as a normal developmental variant rather than considered a pathologic lesion, although carcinoma can develop in the accessory tissue. A specific, radiography-aided diagnosis of accessory axillary breast tissue can eliminate unnecessary biopsy.  相似文献   
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There is evidence that fenfluramine improves insulin action independently of its anorectic and weight-loss-inducing properties. Chronic d-fenfluramine also reduces hypothalamic noradrenergic tone, which correlates highly with hepatic glucose output. We report that chronic d-fenfluramine (5 mg.kg-1.day-1) ameliorates insulin resistance induced by high-fat feeding. Insulin action was assessed in adult male rats at basal insulin levels and at hyperinsulinemia (approximately 140 mU/L with the euglycemic clamp technique). Hepatic glucose production, peripheral glucose disposal, and individual tissue glucose metabolism were determined from bolus injections of [3H]-2-deoxyglucose and [14C]glucose. Food intake was matched between groups. Basal glucose turnover was reduced 28% (P less than .05) in fat-fed rats receiving d-fenfluramine (fat + fen). The glucose infusion rate to maintain euglycemia was 22.0 +/- 1.1 mg.kg-1.min-1 in the high-carbohydrate-fed rats, 8.2 +/- 1.0 in fat-fed rats, and 15.1 +/- 0.5 in the fat + fen group. Peripheral glucose disposal, reflecting measured skeletal muscle changes, was reduced by fat feeding (from 23.5 +/- 1.0 to 13.8 +/- 0.6 mg.kg-1.min-1) but was improved by d-fenfluramine (16.9 +/- 0.5, P less than .05 vs. fat fed). Impaired suppression of hepatic glucose output by insulin, caused by fat feeding, was totally reversed by d-fenfluramine. Thus, d-fenfluramine counteracted diet-induced insulin resistance, with the predominant effect on the liver. We hypothesize that d-fenfluramine improves insulin action by reducing hypothalamic noradrenergic tone, which in turn reduces the neural drive to hepatic glucose output and improves the hepatic response to insulin.  相似文献   
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Nyberg  DA; Mack  LA; Benedetti  TJ; Cyr  DR; Schuman  WP 《Radiology》1987,164(2):357-361
Sixty-nine cases of placental abruption and placental hemorrhage detected with ultrasonography (US) were reviewed retrospectively to determine whether US findings correlate with fetal outcome. Four patients were lost to follow-up, and in the remaining 65 patients fetal outcome included demise in 12 cases (18%), termination of pregnancy in six (9%), premature delivery of a living infant in 15 (23%), term delivery of an infant who was small for gestational age in four (6%), and normal term delivery in 28 (43%). Fetal mortality correlated best with the estimated percentage of placental detachment, but was also significantly (P less than .01) associated with the location (retroplacental) and size (greater than 60 ml) of hemorrhage. Premature labor was associated (P less than .001) only with gestational age at the time of clinical presentation. No sonographic finding was identified as a risk factor for small-for-gestational-age infants. Sonographic findings of placental abruption correlate with fetal outcome, and this information may be useful for guiding obstetric management.  相似文献   
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