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41.
Dolan KA Shearer J White B Zhou J Kaldor J Wodak AD 《Addiction (Abingdon, England)》2005,100(6):820-828
AIMS: To examine the long-term impact of methadone maintenance treatment (MMT) on mortality, re-incarceration and hepatitis C seroconversion in imprisoned male heroin users. DESIGN, SETTING AND PARTICIPANTS: The study cohort comprised 382 imprisoned male heroin users who had participated in a randomized controlled trial of prison-based MMT in 1997/98. Subjects were followed-up between 1998 and 2002 either in the general community or in prison. MEASUREMENTS: All-cause mortality, re-incarceration, hepatitis C and HIV serostatus and MMT retention. FINDINGS: There were no deaths recorded while subjects were enrolled in MMT. Seventeen subjects died while out of MMT, representing an untreated mortality rate of 2.0 per 100 person-years (95% CI, 1.2-3.2). Re-incarceration risk was lowest during MMT episodes of 8 months or longer (adjusted hazard ratio 0.3 (95% CI, 0.2-0.5; P < 0.001), although MMT periods 2 months or less were associated with greatest risk of re-incarceration (P < 0.001). Increased risk of hepatitis C seroconversion was significantly associated with prison sentences of less than 2 months [adjusted hazard ratio 20 (95% CI, 5-76; < P = 0.001)] and MMT episodes less than 5 months [adjusted hazard ratio 4.2 (95% CI, 1.4-12.6; P = 0.01)]. Subjects were at greatest risk of MMT dropout during short prison sentences of 1 month or less (adjusted hazard ratio 10.4 (95% CI, 7.0-15.7; P < 0.001). HIV incidence was 0.3 per 100 person-years (95% CI, 0.03-0.99). CONCLUSIONS: Retention in MMT was associated with reduced mortality, re-incarceration rates and hepatitis C infection. Prison-based MMT programmes are integral to the continuity of treatment needed to ensure optimal outcomes for individual and public health. 相似文献
42.
C Rizan J Ansell TW Tilston N Warren J Torkington 《Annals of the Royal College of Surgeons of England》2015,97(8):549-555
Introduction
Self-assessment is a way of improving technical capabilities without the need for trainer feedback. It can identify areas for improvement and promote professional medical development. The aim of this review was to identify whether selfassessment is an accurate form of technical skills appraisal in general surgery.Methods
The PubMed, MEDLINE®, Embase™ and Cochrane databases were searched for studies assessing the reliability of self-assessment of technical skills in general surgery. For each study, we recorded the skills assessed and the evaluation methods used. Common endpoints between studies were compared to provide recommendations based on the levels of evidence.Results
Twelve studies met the inclusion criteria from 22,292 initial papers. There was no level 1 evidence published. All papers compared the correlation between self-appraisal versus an expert score but differed in the technical skills assessment and the evaluation tools used. The accuracy of self-assessment improved with increasing experience (level 2 recommendation), age (level 3 recommendation) and the use of video playback (level 3 recommendation). Accuracy was reduced by stressful learning environments (level 2 recommendation), lack of familiarity with assessment tools (level 3 recommendation) and in advanced surgical procedures (level 3 recommendation).Conclusions
Evidence exists to support the reliability of self-assessment of technical skills in general surgery. Several variables have been shown to affect the accuracy of self-assessment of technical skills. Future work should focus on evaluating the reliability of self-assessment during live operating procedures. 相似文献43.
Yang OO Boscardin WJ Matud J Hausner MA Hultin LE Hultin PM Shih R Ferbas J Siegal FP Shodell M Shearer GM Grene E Carrington M O'Brien S Price CB Detels R Jamieson BD Giorgi JV 《AIDS research and human retroviruses》2002,18(14):1051-1065
The host immune factors that determine susceptibility to HIV-1 infection are poorly understood. We compared multiple immunologic parameters in three groups of HIV-1-seronegative men: 14 highly exposed (HR10), 7 previously reported possibly to have sustained transient infection (PTI), and a control group of 14 low risk blood bank donors (BB). Virus-specific cellular immune assays were performed for CD4(+) T helper cell responses, CD8(+) cytotoxic T lymphocyte activity, CD8(+) cell chemokine release, and CD8(+) cell-derived antiviral soluble factor activity. General immune parameters evaluated included CCR5 genotype and phenotype, interferon alpha production by PBMCs, leukocyte subset analysis, and detailed T lymphocyte phenotyping. Comparisons revealed no detectable group-specific differences in measures of virus-specific immunity. However, the HR10 group differed from the BB group in several general immune parameters, having higher absolute monocyte counts, higher absolute CD8(+) T cell counts and percentages, lower naive and higher terminal effector CD8(+) cells, and lower levels of CD28(+)CD8(+) cells. These changes were not associated with seropositivity for other chronic viral infections. The PTI men appeared to have normal levels of monocytes and slightly elevated levels of CD8(+) T cells (also with increased effector and decreased naive cells). Although we cannot entirely exclude the contribution of other chronic viral infections, these findings suggest that long-lived systemic cellular antiviral immunity as detected by our assays is not a common mechanism for resistance to infection, and that resistance may be multifactorial. General immune parameters reflected by CD8(+) T cell levels and activation, and monocyte concentrations may affect the risk of infection with HIV-1, and/or serve as markers of exposure. 相似文献
44.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen. 相似文献
45.
Approximately 6% of paediatric patients with precursor B-cell acute lymphoblastic leukaemia (B-ALL) harbour a rearrangement involving the gene regions of PBX1 (1q23) and E2A (19p13.3) which is visualized cytogenetically either as a der(19)t(1;19)(q23;p13.3) or the less common balanced t(1;19)(q23;p13.3). Unfortunately, no commercial dual-colour, double fusion fluorescence in situ hybridization (D-FISH) strategies are available to detect this recurrent anomaly. Therefore, we have created a D-FISH assay to detect these translocations and monitor minimal residual disease. This probe set was created using four bacterial artificial chromosomes (BACs) corresponding to the PBX1 gene region at 1q23 and four BACs corresponding to the E2A gene region at 19p13.3. We analysed 30 negative bone marrow controls and 20 diagnostic and post-treatment specimens from 13 paediatric B-ALL patients with a cytogenetically defined 1;19 translocation. Once unblinded, the results demonstrated that our D-FISH method effectively identified all diagnostic samples as abnormal and identified disease in four post-treatment samples that were previously considered to be normal by conventional cytogenetic analysis. The development of this FISH strategy for the detection of der(19)t(1;19)(q23;p13.3) and t(1;19)(q23;p13.3) proved to be an effective technique, allowing both the detection of disease in diagnostic samples and in post-treatment samples. 相似文献
46.
Experimental design for stable genetic manipulation in mammalian cell lines: lentivirus and alternatives 下载免费PDF全文
Robert F. Shearer Darren N. Saunders 《Genes to cells : devoted to molecular & cellular mechanisms》2015,20(1):1-10
The use of third‐generation lentiviral vectors is now commonplace in most areas of basic biology. These systems provide a fast, efficient means for modulating gene expression, but experimental design needs to be carefully considered to minimize potential artefacts arising from off‐target effects and other confounding factors. This review offers a starting point for those new to lentiviral‐based vector systems, addressing the main issues involved with the use of lentiviral systems in vitro and outlines considerations which should be taken into account during experimental design. Factors such as selecting an appropriate system and controls, and practical titration of viral transduction are important considerations for experimental design. We also briefly describe some of the more recent advances in genome editing technology. TALENs and CRISPRs offer an alternative to lentivirus, providing endogenous gene editing with reduced off‐target effects often at the expense of efficiency. 相似文献
47.
48.
Shearer PM Stark PB 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(3):717-721
The recent elevated rate of large earthquakes has fueled concern that the underlying global rate of earthquake activity has increased, which would have important implications for assessments of seismic hazard and our understanding of how faults interact. We examine the timing of large (magnitude M≥7) earthquakes from 1900 to the present, after removing local clustering related to aftershocks. The global rate of M≥8 earthquakes has been at a record high roughly since 2004, but rates have been almost as high before, and the rate of smaller earthquakes is close to its historical average. Some features of the global catalog are improbable in retrospect, but so are some features of most random sequences--if the features are selected after looking at the data. For a variety of magnitude cutoffs and three statistical tests, the global catalog, with local clusters removed, is not distinguishable from a homogeneous Poisson process. Moreover, no plausible physical mechanism predicts real changes in the underlying global rate of large events. Together these facts suggest that the global risk of large earthquakes is no higher today than it has been in the past. 相似文献
49.
Acute aortic dissection (AAD) is a rare and lethal disease with presenting signs and symptoms that can often be seen with other high risk conditions; diagnosis is therefore often delayed or missed. Pain is present in up to 90% of cases and is typically severe at onset. Many patients present with acute on chronic hypertension, but hypotension is an ominous sign, often reflecting hemorrhage or cardiac tamponade. The chest x-ray can be normal in 10-20% of patients with AAD, and though transthoracic echocardiography is useful if suggestive findings are seen, and should be used to identify pericardial effusion, TTE cannot be used to exclude AAD. Transesophageal echocardiography, however, reliably confirms or excludes the diagnosis, where such equipment and expertise is available. CT scan with IV contrast is the most common imaging modality used to diagnose and classify AAD, and MRI can be used in patients in whom the use of CT or IV contrast is undesirable. Recent specialty guidelines have helped define high-risk features and a diagnostic pathway that can be used the emergency department setting. Initial management of diagnosed or highly suspected acute aortic dissection focuses on pain control, heart rate and then blood pressure management, and immediate surgical consultation. 相似文献
50.
Erik J. Kramer David W. Shearer Elliot Marseille Billy Haonga Joshua Ngahyoma Edmund Eliezer Saam Morshed 《World journal of surgery》2016,40(9):2098-2108