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81.
Impalement injuries to the upper extremity are rare. A case is described of penetration of a 10 x 3.5-inch fence post into the left shoulder of a 16-year-old boy, pinning the shoulder to the chest wall. Sequelae of potential serious brachioplexus, vascular, and intrathoracic injuries are reviewed. The author presents a systematic treatment approach to the assessment, extrication, and microneurovascular repair of damaged structures, and to soft tissue reconstruction following massive foreign body injuries.  相似文献   
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Lymphocytes were cultured from cardiac biopsies following heart transplantation using interleukin-2-conditioned medium. Using the technique of limiting dilution analysis the frequency of donor specific cytotoxic T lymphocytes was measured in cells cultured from biopsies and compared with that in peripheral blood lymphocytes taken at the same time as the biopsy. The graft cell population showed a considerably higher frequency of donor-specific CTL when compared with the PBL. CTL frequencies in the graft cells were always higher against the donor than against third-party cells. These data demonstrate that there was either selective sequestration or selective expansion of donor-reactive T cells in the heart following cardiac transplantation. These results emphasize the need to investigate more closely the events occurring in the heart, and may explain the lack of specificity and sensitivity in immune monitoring (IM) or cytoimmune monitoring (CIM) seen in many centers.  相似文献   
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The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts.  相似文献   
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Advancing age is associated with a remarkable number of changes in body composition, including reduction in lean body mass and increase in body fat, which have been well documented. Decreased lean body mass occurs primarily as a result of losses in skeletal muscle mass. This age-related loss in muscle mass has been termed “sarcopenia”. Loss in muscle mass accounts for the age-associated decreases in basal metabolic rate, muscle strength, and activity levels, which, in turn are the cause of the decreased energy requirements of the elderly. In sedentary persons, the main determinant of energy expenditure is fat-free mass, which declines by about 15% between the third and eighth decade of life. It also appears that declining energy needs are not matched by an appropriate decline in energy intake, with the ultimate result being increased body fat content. Increased body fatness and increased abdominal obesity are thought to be directly linked to the greatly increased incidence of non-insulin-dependent diabetes mellitus among the elderly. In this review we will discuss the extent to which regularly performed exercise can affect nutrition needs and functional capacity in the elderly. We will also discuss a variety of concerns when prescribing exercise in the elderly, such as planning for a wide variability in functional status, medical status, and training intensity and duration. Finally, we will attempt to provide some basic guidelines for beginning an exercise program for older men and women and establishing community-based programs.  相似文献   
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Health care services and resources for older persons living in rural areas may be highly variable, and integrated service-delivery models are often lacking. This article presents a managed-care model of nutrition risk screening and intervention for older persons in rural areas. Nutrition risk screening was implemented by the Geisinger Health Care System, Danville, Pa, to target all eligible enrollees in a regional Medicare risk program. A single remote clinic site participating in the managed health care system was chosen for further study of a linked screening and case-management effort for undernourished persons. Screening and intervention at the clinic site selected for this study were guided by centralized expertise and resources. Individualized evaluation and intervention plans were developed with the aid of a dietitian and implemented by the clinic case manager. Of the 417 subjects who completed screening at the remote site, 68 met the risk criteria for undernutrition and were selected for case management. Many of the targeted persons received interventions that included evaluations by a physician or physician extender (eg, physician assistant, nurse practitioner) at the clinic and consultations with nutrition, mental health, or social services professionals. Twenty-six of the subjects who took part in the intervention completed a follow-up screening 6 months later. Ten of those persons no longer exhibited risk criteria. This demonstrates the feasibility of a linked screening and case management program for nutrition risk in the managed-care setting. J Am Diet Assoc. 1997; 97: 885-888.  相似文献   
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