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961.
962.
The sera of patients with pemphigus, a group of autoimmune blistering skin diseases, contain autoantibodies directed against components of adhering junctions termed desmosomes. F12, a human monoclonal antibody derived from a pemphigus patient, recognizes an unknown polypeptide of the desmosomal and hemidesmosomal plaques. The third complementarity-determining region of the F12 heavy chain (VH-CDR3) was shown to share a four-amino-acid sequence (GSSG) with the intracellular domains of desmoglein 1 and bullous pemphigoid antigen 2 which interact with components of, respectively, the desmosomal and hemidesmosomal plaques. Computer modeling of F12 showed that the GSSG sequence protudes inside the antigen-combining site and thus might be involved in antigen interactions. The GSSG sequence is essential to F12 function, since a peptide containing the VH-CDR3 inhibited its binding to target antigens while VH-CDR3 peptides with specific modifications of the GSSG sequence did not. These data allow us to hypothesize that certain autoantibodies produced during the course of an autoimmune disease can behave as adhesion molecules, through the molecular mimicry of the motif involved in protein/protein adhesion, and to propose a new self-antigen binding mechanism for some autoantibodies.  相似文献   
963.
Acquired immunodeficiency syndrome (AIDS) is a serious disease that has special concern for the health care provider. AIDS has continued to grow despite control efforts. As the disease infectivity period remains lengthy, and the heterosexual population is affected to a greater degree, the level of anxiety has also risen despite educational endeavours. Many fears and anxieties have been associated with AIDS patients by health care workers. The reduction of stress, perceived risk and discomfort following educational efforts have been supported in past research. Educational programmes will need to be given for current health care workers at all levels as well as nursing students. Future nurses must be prepared to meet this challenge. This study was conducted using a convenience sample of nursing students at a university in western United States. Its purpose was to assess any changes that occurred in state anxiety following an educational presentation. Spielberge's State-Trait Anxiety Inventory was used as the measurement instrument. Some anxiety levels were significantly reduced.  相似文献   
964.
Placental growth hormone is the product of the GH-V gene specifically expressed in the syncytiotrophoblast layer of the human placenta. Placental growth hormone differs from pituitary growth hormone by 13 amino acids. It has high somatogenic and low lactogenic activities. Assays by specific monoclonal antibodies reveal that in the maternal circulation from 15 to 20 weeks up to term placental growth hormone gradually replaces pituitary growth hormone, which becomes undetectable. It is secreted by the placenta in a nonpulsatile manner. This continuous secretion appears to have important implications for physiologic adjustment to gestation and especially in the control of maternal insulin-like growth factor-I levels. Placental growth hormone secretion is inhibited by glucose in vitro and in vivo and is significantly decreased in the maternal circulation in pregnancies with intrauterine growth restriction. Placental growth hormone does not appear to have a direct effect on fetal growth because this hormone is not detectable in the fetal circulation. However, the physiologic role might also include a direct influence on placental development through an autocrine or paracrine mechanism, as suggested by the presence of specific growth hormone receptors in this tissue.(Am J Obstet Gynecol 1997;177:1526-34.)  相似文献   
965.
Decision-making and paediatric pain: a review   总被引:1,自引:0,他引:1  
The aim of this paper is to present an overview of the literature on the factors influencing decision-making the nursing care of children in pain. To that effect published and unpublished references werr reviewed. The most frequently cited factors influencing the assessment and management of pain in children are summarized and discussed. Finally recommendations are made where further research is warranted.  相似文献   
966.
Communications among staff and patients on a stroke rehabilitation ward form the focus of this article, which reports on some aspects of a larger study using a grounded theory approach. Tape-recorded interviews were transcribed and analysed concurrently according to recommendations for the approach. A main theme entitled building a relationship was identified, and this process was found to occur in a context varying from participative at one end of a continuum to hierarchical at the other. Building a relationship was found to be influenced by role, personal qualities and organizational context. Appropriate relationships between role-holders were subject to negotiation, leading to a resulting congruence or incongruence between participants' expectations of each other and their roles. Personal qualities were brought into play in the process, with patients' views of staff and staff views of patients both being influential. Some of these views seemed to parallel what has been described in earlier literature as ‘the sick role’ and the labelling of patients as ‘good’ or ‘bad’. Responses to personal qualities led to nurses ascribing meaning to patients' behaviour in terms of adjustment to their stroke, giving time to them to help them to adjust, and withdrawal and handing over to other staff if this strategy failed. Organizational context also had an influence on building a relationship, with time constraints being identified particularly by nurses, and the need to fit in the most essential aspects of care. Place was also important, in that nurses were confined to the ward as a work location, whereas other therapists and doctors worked in other places and sometimes had the facility to take patients off the ward to concentrate on therapy. The findings are discussed against the background of related literature and the conclusion is drawn that the crucial role of nurses in rehabilitation is not recognized and valued, and that shortages of resources - especially suitably qualified and trained nursing staff- are a negative influence on building the relationships which are vital to successful rehabilitation.  相似文献   
967.
A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre-registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers'academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers'clinical development if the rhetoric of policy is to become a reality.  相似文献   
968.
969.
The National Collegiate Athletic Association (NCAA) mandates the use of brightly colored, intraoral mouth- guards by football players to reduce the frequency and severity of craniofacial and intraoral morbidity and mortality, and to enhance the ability of officials to observe player compliance. The purpose of this 12-question mail survey was to determine the attitudes of on-Held game officials regarding current NCAA mouthguard regulations and patterns of utilization by college football players. The sample consisted of all 50 Big East Football Conference officials; a response rate of 100 percent was achieved. Only 42 percent of the officials reported observing all players in compliance, and quarterbacks were identified by others as the least compliant group (52%). The majority (88%) indicated that the 1990 rule for brightly colored mouthguards had been beneficial to them in determining player compliance, and 52 percent reported that this rule had resulted in more frequent use by these athletes. Nearly all officials (96%) indicated that they would issue a warning for noncompliance to the player or coach, rather than charging a timeout for a violation as prescribed by NCAA regulations. The majority (70%) believe current enforcement is appropriate, but expressed the opinion that coaches should be held more accountable for player compliance.  相似文献   
970.
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