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61.
This research project was undertaken as a component of a comprehensive assessment of the University of Connecticut's freshman football team. The purpose of this study was to identify weaknesses in the neck musculature and note any relationships between strength differences and cervical spine stability. Neck muscle strength was evaluated using isometric contractions for the motions of flexion, extension, and right and left lateral flexion. Statistical correlations were derived for each of the 28 male subjects, who were divided into two groups of 14 linemen and 14 runningbacks. A Human Performance Regulator, which electrically evaluates neuromuscular force produced during an isometric contraction, was used to measure the force applied. A typical weightlifting power rack was used as a stabilization platform. The data recorded indicates that there are significant differences between the neck muscle strength of the two groups, as well as differences in neck muscle strength of individuals between their right and left sides. Looking at these muscular differences and their relationship to cervical vertebrae alignment during lateral flexion, the authors contend that blocking or tackling with the head in a laterally flexed position, to supposedly hit with the shoulder, places the cervical spine in a structurally weak position lacking muscular support, and predisposes the athlete to cervical spine injuries. J Orthop Sports Phys Ther 1987;8(7):351-356.  相似文献   
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Chick ciliary ganglion neurons have a membrane component that shares an antigenic determinant with the "main immunogenic region" of the alpha subunits in nicotinic ACh receptors from skeletal muscle and electric organ. Ultrastructural studies on antibody binding in the ganglion have shown that the cross-reacting antigen on the neuron surface is located predominantly in synaptic membrane. Biochemical studies have shown that the cross-reacting component has a number of other properties expected for the ganglionic nicotonic ACh receptor and that it is distinct from the alpha-bungarotoxin binding component in the tissue. Here we show that ciliary ganglion neurons grown in dissociated cell culture express a similar component that cross-reacts with monoclonal antibodies to ACh receptors, and that the number of antibody-binding sites on the neurons can be modulated by exposure to cholinergic agonists and a protein neurotoxin that reversibly inhibits ACh receptors on the neurons. In most, though not all, cases, levels of ACh sensitivity associated with the neurons are specifically comodulated in parallel with the changes in number of antibody binding sites. The results suggest that at least a portion of the cross-reacting sites on the surface of ciliary ganglion neurons is likely to represent nicotinic ACh receptors. The fact that in some instances levels of ACh sensitivity can be altered without changing the number of cross-reacting sites, however, leaves open the possibility that not all of the sites are associated with receptors or that the neurons can alter the proportion of receptors that is functional.  相似文献   
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In a review of cases of fibrous cartilaginous dysplasia of bone, five of fibrocartilaginous lesions were found to be different in clinical behavior and radiographic and morphologic features from the others. We have named these previously undescribed tumors fibrocartilaginous mesenchymomas with low-grade malignancy in the fibrous elements.Dr. Bertoni is a visiting surgical pathologist from the Servizio di Anatomia ed Istologia Patologica, Bologna, Italy  相似文献   
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Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5...  相似文献   
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Thirteen girls with Rett's syndrome were evaluated with wakefulness and sleep polygraphic records and EMG studies. The main EEG findings were paroxysmal activity during sleep, multifocal in younger and unifocal in older girls, and "pseudorhythmic flattening". In the opinion of the authors, the changes with age are related to evolution of the disease or maturational changes of CNS. The affectation of the peripheral nervous system was demonstrated in almost half the patients.  相似文献   
69.
A study is made in the Intensive Care Unit of "José L. Miranda" Provincial Pediatric Teaching Hospital in Santa Clara in order to know the sequence with which the father occupies the place of the mother in the care of hospitalized children. With this objective, 54 male companions are surveyed in the first trimester of 1987. The prevailing occupational profile was that of worker. A higher number of the respondents were between 17 and 25 years of age. The school level of secondary school prevailed among patient companions. Most of them reported no economic inconveniences during the child's disease. The desire to remain at the bedside and the inability of the mother to do so were the major reasons for their stay. The advantages recognized by the nursing personnel in male companions are made known.  相似文献   
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PURPOSE OF THE PAPER. The purposes of this report were to identify Pacific American health care priorities, recommend how these needs can be addressed in national health care reform legislation, and inform national leaders of the cultural and social context withing which these needs must be met. SUMMARY OF METHODS UTILIZED. In concert with a team of researchers, the authors compiled and analyzed extant literature on the health care of Pacific Americans; discussions were held with health care professionals, state and territorial health care leaders, and agencies and organizations with substantial experience and expertise in health care promotion and development; a two-day health symposium was conducted by Pacific American health care community leaders to review the initial findings, conclusions, and recommendations of the draft report; and follow up meetings were heald with actual communitiy health care providers to validate the data and recommendations of the report. PRINCIPAL FINDINGS. Pacific Americans have collective historical and political relationship not only with the federal government and the continental United States, but also to each other's island state or territory. Thus, common needs and unique interrelationships serve to highlight the importance of the differences between western-oriented and Pacific American health care providers. There is a profound lack of health resources in many Pacific American communities, and even when health resources are potentially available, poor access to health care compounds the need. Pacific Americans are a mobile people with large numbers residing in California, Oregon, Washington, Nevada, Texas, Utah, and the New York-Virginia corridor. Their health needs continue even when they do not reside in their home bases. CONCLUSIONS. Pacific Americans know best how to bridge the cultural gap that continues to exist between them and western-oriented health care providers; improvements in their health care is best accomplished by Pacific Americans themselves. Pacific American health care did not start from an "Even playing field"; hence, the mismatch in resources and needs is so pronounced that it argues not only for continued but also greatly expanded federal support for enabling services, research development, and professional education and development. The federal government must collect and develop better demographic and health access information specifically and separately for Pacific Americans. Baseline data for Pacific American populations, regardless of their residence, must be available and analyzable in terms of community and/or geographic areas. Only then can effective programs be established, managed, evaluated, and improved. KEY WORDS. American Samoans; Chamorrors; Hawaiians; Pacific Americans; Pacific Islanders&semi.  相似文献   
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