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991.
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   
992.
The use of in vitro immunization technology for the generation of human antigen-specific antibodies has essentially resulted in low affinity IgM antibodies, resembling an in vivo primary immune response. We now describe a detailed reproducible protocol for a two-step in vitro immunization, which yields isotype switched, antigen-specific human antibodies. The immunizing antigen was a 30aa synthetic peptide, containing both a B (15aa V3 peptide of the HIV-1) and a T helper cell epitope (15aa peptide from tetanus toxin). The immunization protocol includes: (i) a selection procedure of donors with a memory T cell response against tetatus toxoid; (ii) immunization of mature naive peripheral B lymphocytes in two distinct phases, involving a primary and a secondary step. None of the donors which were examined after primary 7immunization showed at any time an IgG anti-V3 specific antibody response, while all the donors showed an IgM response. After the secondary immunization step, anti-V3 antibodies of both IgM and IgG isotypes were detected. The switch frequency event was high among the tested donors (5/8).  相似文献   
993.
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   
994.
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   
995.
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   
996.
997.
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   
998.
999.
Male and female dropouts and graduates (N = 248) from a traditional drug-free therapeutic community were followed 2 years after treatment. A 4-hr face-to-face interview traced the social adjustment one year pre-, through all years posttreatment. Results showed that (a) success (no crime and no opioid and/or no use of nonopioid primary drug) was maintained through 2 years of follow-up by 34% of the dropouts and 68% of the graduates; (b) success rates were highest among opioid abusers and the lowest among primary alcohol abusers; (c) among the latter, however, abstinence rates were significantly increased and daily use of alcohol significantly decreased as did criminal involvement; (d) among the opioid abstinent group, alcohol use increased posttreatment but heavy drinking was not prominent indicating no significant shift in substance dependency. Overall, the therapeutic community appears most effective for opioid abusers but has a clear impact on a considerable number of those primarily involved with alcohol and other substance use.  相似文献   
1000.
Little is known of the impact of pressure ulceration on adult patients' health-related quality of life. The purpose of this study was to determine the impact pressure ulceration has on pressure ulcer patients cared for in the community. A case control study design was used by drawing a random sample from patients receiving community nursing care, stratified by the presence of pressure ulceration. In all, 75 patients with pressure ulcers were compared with 100 controls without ulcers using the four-point ulcer grading scale described by United Kingdom consensus guidelines. Patients were interviewed using the Short Form-36 (SF-36) questionnaire and activities of daily living assessed using the modified Barthel scale. Patients with pressure ulcers had significantly poorer physical function (mean difference (d) = 37.6, 95% CI 28.6-46.6, p < 0.001) and social functioning (d = 33.9, 95 % CI 24.0-43.9, p < 0.001) than published age- and sex-matched normative data from the United Kingdom. The difference between cases and controls was much smaller in these domains, with neither approaching statistical significance. After adjustment for age and gender, scores for bodily pain were poorer in patients with no ulceration (d = -10.5, 95% CI - 20.6 to - 0.4, p = 0.042) indicating greater pain in these patients compared with the cases with ulceration. Activities of daily living determined by the modified Barthel scale showed reduced self-care (d = -7.6, 95% CI -12.5 to - 2.7, p = 0.010) and mobility (d = -9.2, 95% CI -14.6 to - 3.8, p = 0.001) in patients with pressure ulceration. The overall ability to perform these activities was also significantly poorer in this group (d = -16.3, 95% CI -27.3 to -5.3, p = 0.004). While patients with pressure ulceration experience some deficits in their health-related quality of life compared with a normal population, these differences are similar to those experienced by other patients receiving community nursing care.  相似文献   
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