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1.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
2.
BACKGROUND: Menstrual disorders are a common presentation in primary care. Wide variations in management as well as discordance between patient and practitioners in relation to presenting problems have been described. AIMS: To explore the model of menstrual disorders used by practitioners in practice. DESIGN OF STUDY: Semi-structured interviews with primary care practitioners. SETTING: One inner London health authority area. METHOD: Constant comparative analysis. RESULTS: Medical practitioners were critical of the guidance provided by gynaecological definitions and texts. Practitioners put more emphasis on defining normality than on defining disorder. Practitioners used a wide range of criteria to judge their patients' complaints and decide on a course of action. Female practitioners had access to personal and professional experience and used this to develop an understanding of women's complaints. Male practitioners in particular were limited by problems in discussing menstruation in detail. Because of the difficulties in assessing patient history, other non-gynaecological factors such as patient age and consulting behaviour informed practitioners' judgements. CONCLUSION: This study draws attention to practitioners' problems in using current definitions of menstrual disorders. The combination of unhelpful medical definitions, lack of standards of normality and difficulties in discussing menstruation resulted in individual practitioners making judgements in idiosyncratic ways. In the absence of a useful gynaecological model, practitioners develop individual, often subjective and gendered models to use in practice.  相似文献   
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The aim of this discursive paper was to explore the development of co‐production and service user involvement in UK university‐based mental health research and to offer practical recommendations for practitioners co‐producing research with service users and survivors, informed by an overview of the key literature on co‐production in mental health and from a critical reflection on applied research through the medium of a case study. The paper is co‐written by a mental health nurse academic and a service user/survivor researcher academic. The authors argue that the implications of co‐production for mental health research remain underexplored, but that both the practitioner and service user/survivor researcher experience and perspective of co‐production in research can provide practical reflections to inform developing research practice. The theories and values of emancipatory research can provide a framework from which both practitioners and service users can work together on a research project, in a way that requires reflection on process and power dynamics. The authors conclude that whilst co‐produced investigations can offer unique opportunities for advancing emancipatory and applied research in mental health, practitioner researchers need to be more radical in their consideration of power in the research process.  相似文献   
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Injecting drug use is commonly reported among gay and bisexual men in Australia. We examined the prevalence and covariates of injecting drug use among men participating in the Sydney Gay Community Periodic Survey between 2004–06 and 2011. In 2004–06, data was collected about which drugs were injected, while in 2011, data was collected about hepatitis C (HCV) and esoteric sexual practices. In 2004–06, 5.6 % of men reported injecting drugs in the previous 6 months; 3.4 % reported methamphetamine injection and 0.4 % heroin injection. In 2011, men who injected drugs were less likely to be employed full-time, and more likely to be HCV-positive, HIV-positive, to have used party drugs for sex, and to have engaged in esoteric sexual practices. The strong associations between injecting drug use, sexual risk practices and blood-borne virus infection suggests the need for combined sexual health and harm reduction services for gay and bisexual men who inject drugs.  相似文献   
8.

Background

Selection of primary care patients for investigation of potential oesophagogastric cancer is difficult, as the symptoms may represent benign conditions, which are also more common.

Aim

To review systematically the presenting features of oesophagogastric cancers in primary care, including open-access endoscopy clinics.

Design and setting

Systematic review and meta-analysis.

Method

MEDLINE®, Embase, the Cochrane Library, and CINAHL were searched for studies of adults who were symptomatic and presented in primary care or open-access endoscopy clinics. Exclusions were being asymptomatic, screening, or recurrent cancers. Data were extracted to estimate the diagnostic performance of features of oesophagogastric cancers and summarised in a meta-analysis.

Results

Fourteen studies were identified. The strongest summary sensitivity and specificity estimates were for: dyspepsia 0.42 (95% confidence interval [CI] 0.29 to 0.56) and 0.48 (95% CI = 0.31 to 0.65); pain 0.41 (95% CI = 0.24 to 0.62) and 0.75 (95% CI = 0.51 to 0.89); and dysphagia 0.32 (95% CI = 0.17 to 0.52) and 0.92 (95% CI = 0.81 to 0.97). Summary positive likelihood ratios (LR+) and diagnostic odds ratios were: dyspepsia 0.79 (95% CI = 0.55 to 1.15) and 0.65 (95% CI = 0.32 to 1.33); pain 1.64 (95% CI = 1.20 to 2.24) and 2.09 (95% CI = 1.57 to 2.77); and dysphagia 4.32 (95% CI = 2.46 to 7.58) and 5.91 (95% CI = 3.56 to 9.82). Corresponding LR+ were: anaemia 4.32 (95% CI = 2.64 to 7.08); nausea/vomiting/bloating 1.07 (95% CI = 0.52 to 2.19); reflux 0.78 (95% CI = 0.47 to 1.78) and; weight loss 5.46 (95% CI = 3.47 to 8.60).

Conclusion

Dysphagia, weight loss, and anaemia show the strongest association but with relatively low sensitivity and high specificity. The findings support the value of investigation of these symptoms, but also suggest that, in a population of patients who are low risk but not no-risk, investigation is not currently recommended.  相似文献   
9.
To investigate hydrophobic test compounds in toxicological studies, solvents like dimethylsulfoxide (DMSO) are inevitable. However, using these solvents, the interpretation of test compound‐induced responses can be biased. DMSO concentration guidelines are available, but are mostly based on acute exposures involving one specific toxicity endpoint. Hence, to avoid solvent–toxicant interference, we use multiple chronic test endpoints for additional interpretation of DMSO concentrations and propose a statistical model to assess possible synergistic, antagonistic or additive effects of test compounds and their solvents. In this study, the effects of both short‐ (1 day) and long‐term (2 weeks) exposures to low DMSO concentrations (up to 1000 µl l?1) were studied in the planarian Schmidtea mediterranea. We measured different biological levels in both fully developed and developing animals. In a long‐term exposure set‐up, a concentration of 500 µl l?1 DMSO interfered with processes on different biological levels, e.g. behaviour, stem cell proliferation and gene expression profiles. After short exposure times, 500 µl l?1 DMSO only affected motility, whereas the most significant changes on different parameters were observed at a concentration of 1000 µl l?1 DMSO. As small sensitivity differences exist between biological levels and developmental stages, we advise the use of this solvent in concentrations below 500 µl l?1 in this organism. In the second part of our study, we propose a statistical approach to account for solvent–toxicant interactions and discuss full‐scale solvent toxicity studies. In conclusion, we reassessed DMSO concentration limits for different experimental endpoints in the planarian S. mediterranea. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
10.
Recently, considerable attention has been focused on the identification of clinically relevant prognostic markers for primary central nervous system lymphomas (PCNSL). The present study investigated whether three morphological features, i.e. necrosis, reactive perivascular T-cell infiltrate and endothelial hyperplasia, and galectin-1 and galectin-3 immunohistochemical expression have prognostic roles in a series of 58 PCNSL samples from 44 immunocompetent and 14 immunocompromised patients. The presence of endothelial hyperplasia (identified in 21% of the assessable cases) was identified as a bad prognostic factor for immunocompetent PCNSL patients, whereas the other morphological features were not associated with any prognostic value. Lymphomatous cells of eight PCNSL cases expressed galectin-3 without any prognostic value, and lymphomatous cells did not express galectin-1. In contrast, endothelial expression of galectin-3 was identified (by means of uni- and multi-variate analyses) as a bad prognostic factor for immunocompetent PCNSL patients. In addition, a combination of endothelial hyperplasia and/or endothelial galectin-3 expression was shown to be an independent prognostic factor for immunocompetent PCNSL patients treated with methotrexate-based chemotherapy. In summary, this study suggests that endothelial-related markers can identify risk groups of PCNSL patients and indicates that galectin-3 could be involved in PCNSL angiogenesis.  相似文献   
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