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31.
Study objective: To determine the effectiveness of life support courses for health care providers on the basis of one of three outcomes: (1) patient mortality and morbidity, (2) retention of knowledge or skills, and (3) change in practice behavior. Methods: English-language articles from 1975 to 1992 were identified through MEDLINE and ERIC searches, bibliographies of articles, and current abstracts. Studies were considered relevant if they included a study population of life support providers, an intervention of any of the identified life support courses, and assessment of at least one of the three listed outcomes. Relevant studies were selected and validity scores were assigned to them by agreement of two independent reviewers, using a structured form to assess validity. Data on setting, methods, participants, intervention, and outcomes were then abstracted and verified. Results: Seventeen of 67 identified studies pertaining to life support courses met the inclusion criteria. (1) All three mortality and morbidity studies indicated a positive impact, with an overall odds ratio of .28 (95% confidence interval [CI], .22 to .37). (2) No net increase in scores was found in 5 of 8 studies of retention of knowledge and in 8 of 9 studies of skills retention. Two of three studies reporting refresher activities yielded positive effects on knowledge retention. Outcomes were not significantly different between groups taught with modular or didactic techniques. (3) Studies assessing behavioral outcome were methodologically weak. Conclusion: Among providers, retention of knowledge and skills acquired by participation in support courses is poor. However, refresher activities increase knowledge retention. Modular courses are as good as lectures for learning course material. There is evidence that use of the Advanced Trauma Life Support course has decreased mortality and morbidity. Further studies of patient outcome and provider behaviors are warranted. [Jabbour M, Osmond MH, Klassen TP: Life support courses: Are they effective? Ann Emerg Med December 1996;28:690-698.]  相似文献   
32.
Most people with a chronic disease actually have more than one, a condition known as multimorbidity. Despite this, the evidence base to prevent adverse disease outcomes has taken a disease-specific approach. Drawing on a conference, Improving Guidelines for Multimorbid Patients, the goal of this paper is to identify challenges to the generation of evidence to support the care of people with multimorbidity and to make recommendations for improvement. We identified three broad categories of challenges: 1) challenges to defining and measuring multimorbidity; 2) challenges related to the effects of multimorbidity on study design, implementation and analysis; and 3) challenges inherent in studying heterogeneity of treatment effects in patients with differing comorbid conditions. We propose a set of recommendations for consideration by investigators and others (reviewers, editors, funding agencies, policymaking organizations) involved in the creation of evidence for this common type of person that address each of these challenges. The recommendations reflect a general approach that emphasizes broader inclusion (recruitment and retention) of patients with multimorbidity, coupled with more rigorous efforts to measure comorbidity and comorbidity burden and the influence of multimorbidity on outcomes and the effects of therapy. More rigorous examination of heterogeneity of treatment effects requires careful attention to prioritizing the most important comorbid-related questions, and also requires studies that provide greater statistical power than conventional trials have provided. Relatively modest changes in the orientation of current research along these lines can be helpful in pointing to and partially addressing selected knowledge gaps. However, producing a robust evidence base to support patient-centered decision making in complex individuals with multimorbidity, exposed to many different combinations of potentially interacting factors that can modify the risks and benefits of therapies, is likely to require a clinical research enterprise fundamentally restructured to be more fully integrated with routine clinical practice.  相似文献   
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Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
38.
Microarray profiling of invasive breast carcinomas has identified subtypes including luminal A, luminal B, HER2-overexpressing, and basal-like. The poor-prognosis, basal-like tumors have been immunohistochemically characterized as estrogen receptor (ER)-negative, HER2/neu-negative, and cytokeratin 5/6-positive and/or epidermal growth factor receptor (EGFR)-positive. The aim of this study was to determine the prevalence of basal-like ductal carcinoma in situ in a population-based series of cases using immunohistochemical surrogates. A total of 245 pure ductal carcinoma in situ cases from a population-based, case-control study were evaluated for histologic characteristics and immunostained for ER, HER2/neu, EGFR, cytokeratin 5/6, p53, and Ki-67. The subtypes were defined as: luminal A (ER+, HER2-), luminal B (ER+, HER2+), HER2 positive (ER-, HER2+), and basal-like (ER-, HER2-, EGFR+, and/or cytokeratin 5/6+). The prevalence of breast cancer subtypes was basal-like (n = 19 [8%]); luminal A, n = 149 (61%); luminal B, n = 23 (9%); and HER2+/ER-, n = 38 (16%). Sixteen tumors (6%) were unclassified (negative for all 4 defining markers). The basal-like subtype was associated with unfavorable prognostic variables including high-grade nuclei (P < .0001), p53 overexpression (P < .0001), and elevated Ki-67 index (P < .0001). These studies demonstrate the presence of a basal-like in situ carcinoma, a potential precursor lesion to invasive basal-like carcinoma.  相似文献   
39.
Identifying mutations in the TP53 gene is important for cancer prognosis, predicting response to therapy, and determining genetic risk. We have developed a high-throughput scanning assay with automatic calling to detect TP53 mutations in DNA from fresh frozen (FF) and formalin-fixed paraffin-embedded (FFPE) tissues. The coding region of the TP53 gene (exons 2-11) was PCR-amplified from breast cancer samples and scanned by high-resolution fluorescent melting curve analyses using a 384-well format in the LightCycler 480 instrument. Mutations were confirmed by direct sequencing. Sensitivity and specificity of scanning and automatic mutation calling was determined for FF tissue (whole genome amplified [WGA] and non-WGA) and FFPE tissue. Thresholds for automatic mutation calling were established for each preparation type. Overall, we confirmed 27 TP53 mutations in 68 primary breast cancers analyzed by high-resolution melting curve scanning and direct sequencing. Using scanning and automatic calling, there was high specificity (>95%) across all DNA preparation methods. Sensitivities ranged from 100% in non-WGA DNA from fresh tissue to 86% in WGA DNA and DNA from formalin-fixed, paraffin-embedded tissue. Scanning could detect mutated DNA at a dilution of 1:200 in a background of wild-type DNA. Mutation scanning by high-resolution fluorescent melting curve analyses can be done in a high-throughput and automated fashion. The TP53 scanning assay can be performed from a variety of specimen types with high sensitivity/specificity and could be used for clinical and research purposes.  相似文献   
40.
Kibar Z, Salem S, Bosoi CM, Pauwels E, De Marco P, Merello E, Bassuk AG, Capra V, Gros P. Contribution of VANGL2 mutations to isolated neural tube defects. Vangl2 was identified as the gene defective in the Looptail (Lp) mouse model for neural tube defects (NTDs). This gene forms part of the planar cell polarity (PCP) pathway, also called the non‐canonical Frizzled/Dishevelled pathway, which mediates the morphogenetic process of convergent extension essential for proper gastrulation and neural tube formation in vertebrates. Genetic defects in PCP signaling have strongly been associated with NTDs in mouse models. To assess the role of VANGL2 in the complex etiology of NTDs in humans, we resequenced this gene in a large multi‐ethnic cohort of 673 familial and sporadic NTD patients, including 453 open spina bifida and 202 closed spinal NTD cases. Six novel rare missense mutations were identified in seven patients, five of which were affected with closed spinal NTDs. This suggests that VANGL2 mutations may predispose to NTDs in approximately 2.5% of closed spinal NTDs (5 in 202), at a frequency that is significantly different from that of 0.4% (2 in 453) detected in open spina bifida patients (p = 0.027). Our findings strongly implicate VANGL2 in the genetic causation of spinal NTDs in a subset of patients and provide additional evidence for a pathogenic role of PCP signaling in these malformations.  相似文献   
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