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Eleven ways in which people might react to life stress were studied in a sample of 576 Edinburgh women. For each item the subjects were asked whether they had reacted that way in general in the past 6 months and whether they had reacted in that way in response to any specific life stresses they had experienced. Being angry with oneself, being angry with others, rumination, use of alcohol, and use of tobacco all discriminated between those who were well and those who were psychiatrically ill at first interview and these items were formed into a 6-point scale of maladaptive reaction, based largely on specific response. The researchers conducted a follow-up analysis of 306 women who were well at first interview, 35 of whom suffered a psychiatric illness episode (23 depression, 12 anxiety) within the subsequent year. Maladaptive reaction at interview one predicted later illness inception, even after taking life stress into account. Several extraneous variables were considered, none of which could explain this effect. Maladaptive reaction seemed sometimes to lead to illness even when there was only minimal later life stress. Attempts to find coping reactions which afford protection against illness inception were unsuccessful.  相似文献   
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Cross-linked polyethylene currently is being introduced in knee prostheses. The wear rates, wear debris, and biologic reactivity of non cross-linked, moderately cross-linked, and highly cross-linked polyethylene have been compared in multidirectional wear tests and knee simulators. Multidirectional pin-on-plate wear studies of noncross-linked, moderately cross-linked (5 Mrad), and highly cross-linked (10 Mrad) polyethylene showed a 75% reduction in wear with the highly cross-linked material under kinematics found in the hip, but only a 33% reduction under wear in kinematics representative of the knee. In knee simulator studies, with the fixed-bearing press-fit, condylar Sigma cruciate-retaining knee under high kinematic input conditions, the wear of 5 Mrad moderately cross-linked polyethylene was 13 +/- 4 mm per 1 million cycles, which was lower (p < 0.05) than the wear of clinically used, gamma vacuum foil GUR 1020 polyethylene (23 +/- 6 mm/1 million cycles). For the low-contact stress mobile-bearing knee, the wear of moderately cross-linked polyethylene was 2 +/- 1 mm per 1 million cycles, which was lower (p < 0.05) than GVF GUR 1020 polyethylene (5 +/- 2 mm/1 million cycles). The wear debris isolated from the fixed-bearing knees showed the moderately cross-linked material had a larger percentage volume of particles smaller than 1 mum in size, compared with GVF GUR 1020 polyethylene. Direct cell culture studies of wear debris generated in sterile wear simulators using multidirectional motion showed a increase (p < 0.05) in tumor necrosis factor-alpha levels and reactivity for GUR 1050 cross-linked polyethylene debris compared with an equivalent volume of noncross-linked GUR 1050 polyethylene. The use of cross-linked polyethylene in the knee reduces the volumetric wear rate. However, the clinical significance of reduced fracture toughness, elevated wear in abrasive conditions, and the elevated tumor necrosis factor-alpha release from smaller more reactive particles warrant further investigation.  相似文献   
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Skin allografts derived from cadaveric human donors are widely used in the treatment of serious burn injuries and other conditions, such as ulcers. In order to render these allografts safe for clinical use, and to enable them to be preserved and banked for long periods, effective methods of decontamination and preservation are required. These methods must not adversely affect graft properties essential for clinical performance. We have investigated the application of a peracetic acid (PAA) disinfection protocol, coupled with preservation in either glycerol or propylene glycol to achieve these goals. An effective decontamination procedure, comprising of a 3h exposure to 0.1% (v/v) PAA in phosphate buffered saline (PBS) at pH 7.0, was developed and had no significant detrimental effects on the structure of skin. Cadaveric skin allografts were then treated with this disinfection protocol and subsequently preserved in either 85% (v/v) glycerol or propylene glycol in PBS, and the biological properties of the allografts thought to be essential to successful clinical performance were assessed. The cytotoxicity of the grafts was assessed using both extract and contact assays; damage to the skin collagen was assessed using a collagenase susceptibility assay and the capacity of the grafts to elicit an inflammatory response in vitro was assessed by quantifying the production of the pro-inflammatory cytokine TNF-alpha by human peripheral blood mononuclear phagocytes. Neither the disinfection protocol nor either of the preservation techniques rendered the grafts cytotoxic or pro-inflammatory. The PAA disinfection and glycerol preservation protocol had no effects on collagenase susceptibility, whereas the disinfection protocol in combination with propylene glycol rendered some of the test samples significantly more susceptible to collagenase digestion. Therefore, this study has demonstrated that PAA disinfection combined with glycerol preservation is suitable for skin allografts. The use of propylene glycol as a preservation agent for skin requires further development.  相似文献   
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Symptom control     
Symptom control has become increasingly recognized as an important goal in patient care. In this article, advances in symptom assessment, and various definitions of symptom improvement are reviewed. Theoretical concepts underlying symptom control and clinically significant change are presented, as well as the role of symptom control as an endpoint in clinical trials. Symptom control is then surveyed in two broad categories for selected symptoms. The first area is therapy related symptoms, secondary to chemotherapy, radiation, hormonal therapy, and surgery. Symptoms reviewed include chemotherapy related mucositis, emesis, fatigue; hot flashes; and radiation related dermatitis, xerostomia, and mucositis. The second area is palliative oncologic approaches to disease-related symptoms. Results in palliative chemotherapy, palliative radiation therapy, cancer pain, and lack of appetite are summarized. Areas requiring further research are noted. Findings are presented in both a clinical and research context to help guide the reader with interpreting symptom control studies.  相似文献   
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PurposeTo explore, using both survey data and case studies, factors that are associated with abortion decisions among young couples in the context of recently legalized abortion in Nepal.MethodsThis article draws primarily on data collected in detailed case histories of 30 participants selected from a sample of the respondents to a survey of 997 married women aged 15 to 24 years and 499 men aged 15 to 27 years collected in 2003. Bivariate analyses of the survey data are presented in summary form to provide some general contextual background, with the key themes that emerged from analysis of the case histories being described.ResultsAlmost half of the young women in the survey reported that they had ever experienced an unintended pregnancy. A considerable proportion of these couples thought about abortion but the majority of them did not take any action. Some of them had attempted abortion but only few had succeeded. Multiple factors, including socio-cultural beliefs, affect the decision-making phase, making the process dynamic and situation-specific. Husbands and health service providers play a major role in the decision-making process.ConclusionsThe study highlights the need to scale up family planning and abortion services to young couples, and emphasizes the importance of involving men and service providers in public education and advocacy campaigns against unsafe abortion. It also points to the need for wider education in the community about family planning and legal abortion services, as well as for the transparent pricing of services and greater efforts to enhance women’s decision-making capacities and control over their reproductive options.  相似文献   
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The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed.  相似文献   
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