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101.
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Sixty-seven patients with 68 stage T4 carcinomas of the skin of the head and neck were treated with radical radiotherapy at the University of Florida between October 1964 and November 1989. Thirty-three lesions were previously untreated and 35 were recurrent. Twenty-nine lesions were squamous cell carcinomas, 37 were basal cell carcinomas, and 2 were basosquamous carcinomas. Minimum follow-up was 2 years. The 5-year local control, local control including surgical salvage, and cause-specific survival probabilities were 53%, 74%, and 75%, respectively. Local control rates with radiotherapy alone were poorer in patients with recurrent lesions (41% vs. 67%, p = .07) or bone involvement (40% vs. 62%, p = .08). Results were analyzed by multivariate methods using local control, local control with surgical salvage, and cause-specific survival as endpoints. The parameters analyzed were histology; size of primary lesion; previous treatment (previously untreated vs. recurrent); involvement of bone, nerve, or cartilage; and skeletal muscle invasion. Three important prognostic factors were identified, each predictive of poorer ultimate local control and cause-specific survival rates: (a) bone involvement (p < .01); (b) recurrent lesions (p < .01); and (c) nerve involvement (p < .02). Radiotherapy alone can control advanced carcinomas of the skin of the head and neck, although lesions that have recurred after prior treatment and those with involvement of bone or nerve are associated with a lower likelihood of cure.  相似文献   
103.
Research ethics committee audit: differences between committees.   总被引:2,自引:2,他引:0  
The same research proposal was submitted to 24 district health authority (DHA) research ethics committees in different parts of the country. The objective was to obtain permission for a multi-centre research project. The study of neonatal care in different types of unit (regional, subregional and district), required that four health authorities were approached in each of six widely separated health regions in England. Data were collected and compared concerning aspects of processing, including application forms, information required, timing and decision-making. The key finding was that ethics committees received and processed the applications variably, reflecting individual factors and local problems. To improve consensus and facilitate multicentre studies, standard forms and instructions are suggested and the establishment of a national committee or advisory group advocated.  相似文献   
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Attainment of a Class I molar relationship (Angle) is often a prime treatment objective. In addition to considerations of improved function and skeletodental harmonies, a Class I relationship often is deemed the "correct" and stable situation. This study assessed the relative stability of the sagittal molar relationship in orthodontically untreated persons with full dentitions who were followed longitudinally from young (approximately 20 years) to older (approximately 55 years) adulthood. The Class I relationship is indeed most stable; none of 69 cases (sides) starting in a Class I cusp-in-groove relationship moved from that condition. In contrast, Class II relationships naturally became significantly "more" Class II (that is, greater distoclusion), and Class III cases shifted significantly to greater mesioclusion.  相似文献   
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Summary Ultrastructural studies of cells and tissues in the acquired immunodeficiency syndrome (AIDS) have revealed two distinct cytomembranous inclusions referred to as tubuloreticular inclusions (TRI) and confronting cylindrical cisterns (CCC). TRI are found most often in leukocytes and endothelial cells in conditions with elevated levels of alpha-interferon, such as viral infections, autoimmune diseases and certain neoplasms. On the other hand, CCC are detected almost exclusively in mononuclear inflammatory cells and are limited to a few conditions, of which AIDS is the most common. CCC have been proposed as an ultrastructural marker for human immunodeficiency virus (HIV) infection. We describe CCC in mononuclear inflammatory cells in the brain of a patient with AIDS. Finding CCC in brain tissue with no other specific feature such as multinucleated giant cells, nevertheless, should alert the neuropathologist to the possibility that the patient might have AIDS.  相似文献   
107.
Superficial skin cancer is the most common malignancy in man, and radiotherapy has played an important curative role since the early part of the 20th century. We present an overview of the changing pattern of care for patients with superficial skin cancer at the Queensland Radium Institute (QRI), Brisbane--the skin cancer "capital" of the world. Although some 90,000 clinically-diagnosed skin cancers have been treated by radiotherapy at the QRI during the period 1944-1985, we document a dramatic decline in radiotherapy usage for superficial skin cancers over the past 10-15 years. We identify and discuss the major reasons for this changing pattern of care: (a) policy changes initiated by radiation oncologists because of unsightly radiation scars caused by the Queensland climate, (b) improvements in the availability and technical aspects of surgery and dermatology, and (c) surgical preference.  相似文献   
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Abstract This study illustrates how the Total Life Concept (TLC) program originated by AT&T was successfully transplanted to another work site, Sandia National Laboratories. Demographics of the participants at A T&T and Sandia differ and make comparisons difficult, but it is possible to assess program impact in terms of participation rates for each program. The original AT&T TLC pilot study had three major components: orientation, testing, and risk interpretation; lifestyle-improvement courses; and activities to promote health. Sandia kept the three major components of the AT&T TLC concept and made some modifications to meet Sandia's needs. Sandia's experience of adopting a model program and tailoring it to local needs worked well, demonstrating that an existing model can be successfully altered to meet the needs of different companies in varied settings.  相似文献   
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