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31.
Case-control studies of genetic factors are prone to a special form of confounding called population stratification, whenever the existence of one or more subpopulations may lead to a false association, be it positive or negative. We quantify both the bias (in terms of confounding risk ratio) and the probability of false association (type I error) in the most unfavorable situation in which only one high-risk subpopulation is hidden within the studied population, considering different scenarios of population structuring and varying sample sizes. In accord with previous work, we find that the bias is likely to be small in most cases. In addition, we show that the same applies to the associated type I error whenever the subpopulation is small in proportion. For instance, when the hidden subpopulation makes up 5% of the entire population, with an allelic frequency of 0.25 (versus 0.10) and a disease rate that is double, then the estimated bias is 1.07 and the type I error associated with a sample of 500 cases and 500 controls is 8% (instead of 5%). We also show that the type I error is substantially greater for a rare allele (frequency of 0.1) than for a common allele (frequency of 0.5) and analyze the pattern of increase of vulnerability to stratification bias with sample size. Based on our findings, we may therefore conclude that with moderate sample sizes the type I error associated with population stratification remains very limited in most realistic scenarios.  相似文献   
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PURPOSE: To evaluate response rate and toxicity of irinotecan and oxaliplatin plus fluorouracil (FU) and leucovorin (Folfirinox) in advanced pancreatic adenocarcinoma (APA). PATIENTS AND METHODS: Chemotherapy-naive patients with histologically proven APA and bidimensionally measurable disease were treated with Folfirinox therapy every 2 weeks, which comprised oxaliplatin 85 mg/m(2) and irinotecan 180 mg/m(2) plus leucovorin 400 mg/m(2) followed by bolus FU 400 mg/m(2) on day 1, then FU 2,400 mg/m(2) as a 46-hour continuous infusion. Quality of life (QOL) was assessed using European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30). RESULTS: Forty-seven patients were entered, and 46 received treatment. Thirty-five patients (76%) had metastatic disease. A total of 356 cycles were delivered, with a median of eight cycles per patient (range, one to 24 cycles). All patients were assessable for safety. No toxic death occurred. Grade 3 to 4 neutropenia occurred in 52% of patients, including two patients with febrile neutropenia. Other relevant toxicities included grade 3 to 4 nausea (20%), vomiting (17%), and diarrhea (17%) and grade 3 neuropathy (15%; Levi's scale). The confirmed response rate was 26% (95% CI, 13% to 39%), including 4% complete responses. Median time to progression was 8.2 months (95% CI, 5.3 to 11.6 months), and median overall survival was 10.2 months (95% CI, 8.1 to 14.4 months). Between baseline and end of treatment, patients had improvement in all functional scales of the EORTC QLQ-C30, except cognitive functioning. Responders had major improvement in global QOL. CONCLUSION: With a good safety profile, a promising response rate, and an improvement in QOL, Folfirinox will be further assessed in a phase III trial.  相似文献   
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Worldwide, more than 230 million adults have major noncardiac surgery each year. Although surgery can improve quality and duration of life, it can also precipitate major complications. Moreover, a substantial proportion of deaths occur after discharge. Current systems for monitoring patients postoperatively, on surgical wards and after transition to home, are inadequate. On the surgical ward, vital signs evaluation usually occurs only every 4-8 hours. Reduced in-hospital ward monitoring, followed by no vital signs monitoring at home, leads to thousands of cases of undetected/delayed detection of hemodynamic compromise. In this article we review work to date on postoperative remote automated monitoring on surgical wards and strategy for advancing this field. Key considerations for overcoming current barriers to implementing remote automated monitoring in Canada are also presented.  相似文献   
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Acute myeloid leukaemia (AML) with t(6;9)(p23;q34) is a poor-risk entity, commonly associated with FLT3-ITD (internal tandem duplication). Allogeneic stem-cell tranplantation (allo-SCT) is recommended, although studies analysing the outcome of allo-SCT in this setting are lacking. We selected 195 patients with t(6;9) AML, who received a first allo-SCT between 2000 and 2016 from the EBMT (European Society for Blood and Marrow Transplantation) registry. Disease status at time of allo-SCT was the strongest independent prognostic factor, with a two-year leukaemia-free survival and relapse incidence of 57% and 19% in patients in CR1 (first complete remission), 34% and 33% in CR2 (second complete remission), and 24% and 49% in patients not in remission, respectively (P < 0·001). This study, which represents the largest one available in t(6;9) AML, supports the recommendation to submit these patients to allo-SCT in CR1.  相似文献   
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Background: The contemporary occupational therapy literature suggests that different quality criteria exist for setting goals in occupational therapy: a focus on occupation; a link to the International Classification of Functioning, Disability, and Health (ICF); and adherence to the SMART recommendations, which advises goals to be specific, measurable, agreed, realistic, and timed. Aim: To identify the extent to which Swiss occupational therapists (OTs) adhere to the criteria cited above. Material: A total of 1 129 goals formulated with the Goal Attainment Scale (GAS) collected in 2008. Results: In slightly more than half the investigated cases at least one goal addressed an aspect of occupation. Nearly two-thirds of the goals related to the ICF component “activity and participation”. Nearly 90% of the goals were specific, measurable, and/or realistic. Conclusions: Goals mirror, to some extent, what is done in everyday practice. Several influences on goal formulations of OTs were identified, including the practice models traditionally used in different specialist fields; the cultural contexts in which OTs were trained; and the legal framework that obliges OTs to formulate their goals in a certain way in order to obtain funding for their services. Significance: Based on these results evidence-based products have been developed (a further education course; written recommendations for practice).  相似文献   
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The proprotein convertases (PCs) furin and PACE4 process numerous substrates involved in tumor growth, invasion, and metastasis. We have previously shown that PCs increase the susceptibility to chemical skin carcinogenesis. Because of the human relevancy of UV radiation in the etiopathogenesis of human skin cancer, we investigated whether or not transgenic mice overexpressing either furin alone or both furin and PACE4 show increased susceptibility to UV carcinogenesis. After backcrossing our previously described furin and PACE4 transgenic lines, targeted to the epidermis, into a SKH-1 background, we exposed both single and double transgenic mice to UV radiation for 34 weeks. The results showed an increase in squamous cell carcinoma (SCC) multiplicity of approximately 70% in the single furin transgenic mouse line SF47 (P < .002) and a 30% increase in the other single transgenic line SF49 when compared to wild-type (WT) SKH-1 mice. Interestingly, there was also an increase in the percentage of high histologic grade SCCs in the transgenic lines compared to the WT mice, i.e., WT = 9%, SF47 = 15%, and SF49 = 26% (P < .02). Targeting both furin and PACE4 to the epidermis in double transgenic mice did not have an additive effect on tumor incidence/multiplicity but did enhance the tumor histopathologic grade, i.e., a significant increase in higher grade SCCs was seen in the bigenic mouse line SPF47 (P < .02). Thus, we observed an increased susceptibility to UV in single furin transgenic mice that was not substantially enhanced in the double furin/PACE4 transgenic mice.  相似文献   
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