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991.
Public health messages emphasizing 'healthy weight' link good health to a narrow range of body weights and stress energy regulation to achieve this. We examined whether women who practise bulimia deploy notions of 'healthy weight' in their talk about body management activities. Analysis is based on interviews with 15 women who practise bulimia and on material collected from cultural locations containing 'health promotion' advice. Poststructuralist discourse analysis revealed that slenderness was constituted as healthy in both sites and that the careful regulation of energy intake and output was similarly reified as a healthy practice. We conclude that a discourse of 'healthy weight' cannot be unhinged from a cultural imperative of slenderness for women, and that paradoxically 'health' practices provide a rationality that supports the practices of binge eating and compensating.  相似文献   
992.
A novel oligomer was synthesized in different molecular masses and used as a primer in dentin bonding. The hypothesis was that an intermediate molecular mass would optimize the conflicting needs for diffusion into etched dentin (low M(w)) and high mechanical properties (high M(w)). The initial oligomer synthesized was tert butylmethacrylate-co-maleic anhydride, which was further reacted to add hyrdoxyethyl methacrylate (HEMA) across the anhydride. The oligomer was synthesized in a series of molecular masses from approximately 800-6000 amu. The oligomer with an average M(w) of approximately 1000 amu provided the highest bond strength (16 MPa), with both lower and higher molar mass oligomers producing lower bond strengths. A polynomial model was fitted to the data with an R(2) = 0.606, while a linear model only had an R(2) = 0.534. This implies that the graph of molar mass to bond strength has a maximum in the range of molar masses examined, and that an optimum molar mass can be found between 800 and 6000 amu.  相似文献   
993.
Cellesi F  Tirelli N  Hubbell JA 《Biomaterials》2004,25(21):5115-5124
We have previously described a gelation process based on the occurrence of both physical and a chemical mechanisms ('tandem process'), in which a telechelic linear poly(propylene glycol)-bl-poly(ethylene glycol)-bl-poly(propylene glycol) is first thermally gelled and subsequently covalently cross-linked by the reaction of polymer end groups at the termini of the copolymer. The quick kinetics of the reverse thermal gelation and the harmless character of the Michael-type addition between two sets of terminal groups, acrylates on one set and thiols on the other, allows irreversibly cross-linked hydrogels to be obtained in a rapid and biocompatible fashion, even when gelation was conducted in direct contact with cells. This allows in principle for an application of the tandem process in cell encapsulation. In the present work, we have optimized the macromolecular architecture and functionality of the precursors for allowing the use of the tandem process in encapsulation devices designed for calcium alginate. The mechanical, diffusional and biocompatibility properties of these materials were characterized; the comparison of mass transport properties of the tandem gels with those of calcium alginate suggests a similar or even better immunoisolation effect.  相似文献   
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BACKGROUND: Although minor facial injuries are relatively common, their psychological impact is an area neglected in the literature. For physiologically major injuries (such as facial cancers, burns and fractures), the face has been suggested to be a psychologically significant area of the body and disfigurement has been found to have numerous potential social consequences for patients. AIMS: This paper reports the findings of an inquiry that explored the psychological impact of minor facial injuries and the influence of patient and scar characteristics in relation to self-consciousness and anxiety levels. METHOD: Data were collected in 2001 in an accident and emergency unit from patients with a visible laceration over 1.5 cm that was treatable in an outpatient setting. The Derriford Appearance Scale (with general and social self-consciousness subscales) and the State-Trait Anxiety Inventory were administered to 63 patients 1 week later; data on 50 patients were also available 6 months after the injury. RESULTS: Larger scar size, living alone and aetiology of injury were significantly related to self-consciousness and anxiety levels, although gender, age, socio-economic group, location of scar, satisfaction with appearance and number of scars were not. General self-consciousness improved at 6 months but social self-consciousness and anxiety remained the same. Patient factors were not related to changes in general self-consciousness over time. CONCLUSIONS: Minor facial scars can have significant psychological impact for some people. Awareness training for health professionals, social skills training for affected patients and a patient information leaflet are recommended.  相似文献   
997.
There is an urgent need for validated, feasible tools to assess doctors' performance. A peer-rating tool mapped to good medical practice (SPRAT) is feasible, valid and reliable. SPRAT is ideal for revalidation purposes and performs particularly well in areas that are traditionally difficult to assess. It can also inform personal development planning.  相似文献   
998.
This retrospective review of reported surgical site infection (SSI) rates in Europe was undertaken to obtain an estimated scale of the problem and the associated economic burden. Preliminary literature searches revealed incomplete datasets when applying the National Nosocomial Infection Surveillance System criteria. Following an expanded literature search, studies were selected according to the number of parameters reported, from those identified as critical for accurate determination of SSI rates. Forty-eight studies were analysed. None of the reviewed studies recorded all the data necessary to enable a comparative assessment of the SSI rate to be undertaken. The estimated range from selected studies analysed varied widely from 1.5-20% - a consequence of inconsistencies in data collection methods, surveillance criteria and wide variations in the surgical procedures investigated - often unspecified. SSIs contribute greatly to the economic costs of surgical procedures - estimated range: 1.47-19.1 billion Euro dollars. The analysis suggests that the true rate of SSIs, currently unknown, is likely to have been previously under-reported. Consequently, the associated economic burden is also likely to be underestimated. A significant improvement in study design, data collection, analysis and reporting will be necessary to ensure that SSI baseline rates are more accurately assessed to enable the evaluation of future cost-effective measures.  相似文献   
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