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1.
We examined the skeletal remains of 1338 early Hawaiians (preserved in the Bishop Museum, Honolulu) to determine total caries and root surface caries prevalence. Specimens from seven islands were represented in the collection. Estimation of age at death was made by a combination of dental developmental staging for younger individuals and occlusal attrition and/or alveolar bone loss in adults. Museum records were also consulted for age estimation of adults which was primarily based on osteological criteria. The material was divided into six age groups. Predentate infants and edentulous adults were not included. A total of 19,425 teeth was examined. Caries lesions were observed in 462 individuals (34.5%) and 1895 teeth (9.8%). Coronal caries lesions in children and adolescents tended to be small and not particularly destructive of tooth structure. Root surface lesions in young adults were also small but increased progressively in size in the older groups, resulting in pulp exposure and coronal amputation. Although coronal caries was apparently not a significant dental health problem in children and young adults (compared with contemporary Hawaiians), root surface caries was an increasingly important source of tooth morbidity and tooth mortality in the older population groups. This age-related caries pattern was similar for all of the islands.  相似文献   
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This paper examines the lack of congruence between national policy documents and local practice in multi-disciplinary working with drug users, by reporting on a case study within one English county. It gives an analysis of the roles and responsibilities of generic service providers and a minority of specialists, based on 100 interviews and questionnaires with representatives from professional groups involved with drug issues. The respondents worked with a range of young people and adults. Whilst professionals worked well within broad disciplines such as health or education, they did not operate as well across disciplinary boundaries. Many of the respondents were unsure about the specific role of their own profession, and which group they should target for drug interventions. There was a lack of clarity about what approach was appropriate to their traditional target group in terms of drugs, and consequently many did not utilize their established approach for that group. When the reasons for the lack of co-working were examined, it was found that there were many misconceptions among professionals concerning what other professional groups actually did in response to drugs. The authors clarify the reasons for the apparent confusion and highlight the possibility that a traditional generic approach and target group may not provide an appropriate match in terms of drug intervention. They make recommendations for overcoming these obstacles to multi-disciplinary working and consider the implications for training.  相似文献   
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An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models.  相似文献   
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‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories.  相似文献   
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FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
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Development of a new wound dressing with antimicrobial delivery capability   总被引:1,自引:0,他引:1  
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.  相似文献   
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