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21.
Pneumosinus dilatans (PD) represents a rare lesion of unknown etiology in which progressive enlargement of an air-filled paranasal sinus results in cosmetic and functional complications. The absence of pathologic mucosa has traditionally been considered a hallmark of this disorder. A 24-year-old man presented with 2 years of chronic rhinosinusitis and recurrent, acute episodes of severe forehead pain with worsening outward prominence of the frontal sinus during air travel. Computed tomography and findings at surgery were notable for diffuse nonpolypoid inflammatory changes of the paranasal sinuses, a type III frontal sinus cell, and PD of the frontal sinus with severe deformity and thinning of the anterior table. A bicoronal approach was used for frontal sinus obliteration and cranioplasty. Excellent cosmetic and functional results were noted at the last follow-up. To our knowledge, this is the first report of PD frontalis presenting in the setting of chronic rhinosinusitis. Surgical management of this disorder requires consideration of both the functional and cosmetic issues.  相似文献   
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Live attenuated viral vectors that express human immunodeficiency virus (HIV) antigens are being developed as potential vaccines to prevent HIV infection. The first phase 2 trial with a canarypox vector (vCP205, which expresses gp120, p55, and protease) was conducted in 435 volunteers with and without gp120 boosting, to expand the safety database and to compare the immunogenicity of the vector in volunteers who were at higher risk with that in volunteers at lower risk for HIV infection. Neutralizing antibodies to the MN strain were stimulated in 94% of volunteers given vCP205 plus gp120 and in 56% of volunteers given vCP205 alone. CD8(+) cytotoxic T lymphocyte cells developed at some time point in 33% of volunteers given vCP205, with or without gp120. Phase 3 field trials with these or similar vaccines are needed, to determine whether efficacy in preventing HIV infection or in slowing disease progression among vaccinees who become infected is associated with the level and types of immune responses that were induced by the vaccines in this study.  相似文献   
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Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
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Objective. To critically appraise evidence of the effectiveness of continuing medical education (CME) in rheumatic diseases for primary care physicians. Methods. Three physicians independently applied preset criteria to evaluated CME interventions published between January 1966 and August 1993. Results. Eight of 166 articles identified were critically appraised, 7 of which had positive results. Marked heterogeneity in educational interventions, evaluative methods, and outcomes was noted. Conclusion. Despite generally positive results, weak methodology precludes drawing firm conclusions about the effectiveness of CME in rheumatic diseases.  相似文献   
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Hematopoietic cell transplantation (HCT) is a potentially curative treatment for children and adults with malignant and nonmalignant diseases. Despite increasing survival rates, long-term morbidity after HCT is substantial. Neurocognitive dysfunction is a serious cause of morbidity, yet little is known about neurocognitive dysfunction after HCT. To address this gap, collaborative efforts of the Center for International Blood and Marrow Transplant Research and the European Society for Blood and Marrow Transplantation undertook an expert review of neurocognitive dysfunction after HCT. In this review we define what constitutes neurocognitive dysfunction, characterize its risk factors and sequelae, describe tools and methods to assess neurocognitive function in HCT recipients, and discuss possible interventions for HCT patients with this condition. This review aims to help clinicians understand the scope of this health-related problem, highlight its impact on well-being of survivors, and help determine factors that may improve identification of patients at risk for declines in cognitive functioning after HCT. In particular, we review strategies for preventing and treating neurocognitive dysfunction in HCT patients. Finally, we highlight the need for well-designed studies to develop and test interventions aimed at preventing and improving neurocognitive dysfunction and its sequelae after HCT.  相似文献   
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Forty healthy limbs and 31 limbs with suspected deep venous insufficiency were imaged with real-time B-mode ultrasound to determine valve location, anatomic characteristics, and function. Valve function was evaluated by comparison with Doppler ultrasonographic techniques, and the data clearly indicated that ultrasonic venography accurately localized and determined the extent of deep venous reflux. Ascending contrast venography was performed in 15 postphlebitic limbs for assessment of valve location. The results indicate that ultrasonic venography is a more accurate method for visualization of valves in this group of patients. Therefore, ultrasonographic imaging is a valuable technique for evaluating limbs with chronic venous insufficiency.  相似文献   
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