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The impact of the acquired immunodeficiency syndrome (AIDS) epidemic on a group of adolescents was investigated by surveying 197 sexually active, predominantly African-American, urban high school students. Reported sexual behavior changes were evaluated in relation to AIDS-related knowledge and attitudes. Over 50% of the students decreased their frequency of sexual activity, increased their condom use, and/or decreased their number of partners. These students had significantly higher scores on a measure of worry about vulnerability to human immunodeficiency virus (HIV) infection than those whose behavior had not changed. AIDS knowledge, AIDS beliefs, and AIDS-related anxiety interacted with gender to affect sexual behavior change. Male students reporting decreased frequency of sexual activity, for example, had more accurate beliefs about AIDS than males reporting no decrease. Among female students, however, those reporting decreased frequency had less accurate beliefs than those reporting no decrease. These results highlight the importance of considering gender and specific sexual behaviors when designing AIDS education interventions.  相似文献   
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IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
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Forty-four patients with Ph positive leukemia (36 developing blast crisis after chronic phase and eight presenting in acute leukemia) were classified into subgroups on the basis of reactivity of blasts with an anti-serum made against non-T,non-B acute lymphoid leukemia (ALL+), levels of terminal transferase enzyme (TdT+) and morphology. Positivity with anti-ALL serum was the most sensitive and reliable marker, and TdT was an important aid. The presence of "lymphoid" blasts in blast crisis of CML was related to the response to chemotherapy incorporating Vincristine and Prednisolone (VP). Patients with ALL+ blasts frequently (14 of 15 cases) responded to therapy while 21 of 25 patients who had no ALL+ blasts failed to respond. The clinical course of the ALL+ patients was variable: eight patients remitted with return to the appearances of the chronic phase; four patients demonstrated elimination of the Ph1 positive clone with hypoplasia and this was followed by normal (Ph1 negative) marrow regeneration in two. Subsequent relapse was of either the ALL+ "lymphoid" or the ALL-myeloid type. A regimen incorporating VP should be the treatment of choice in "lymphoid" blast crisis of CML.  相似文献   
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A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.  相似文献   
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It generally is believed that physicians who have poor relationships with their patients are more likely to be sued. We studied certain physician characteristics and related them to their number of malpractice suits and the amount paid to settle those claims. Physicians with better rapport with their patients, who took more time to explain, and who were available had fewer malpractice suits. The most significant correlation was found in time spent with the patient. As the time spent increased, the number of suits decreased.  相似文献   
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