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51.
目的 研究胸段食管癌逆向调强放射治疗(IMRT)中累及野照射与扩大野照射对危及器官(OAR)受照剂量的影响。方法 40例胸段食管癌患者分别行累及野靶区勾画和扩大野靶区勾画并勾画危及器官,制定IMRT计划,评估2个计划的靶区适形指数(CI)和均匀性指数(HI)及危及器官的剂量学参数,剂量学参数比较采用配对t检验。结果 2种计划的PTV均能满足处方剂量要求,PTV在CIHI上相近(P = 0.317、0.130)。两组间平均肺剂量、两肺V5、两肺V20、两肺V30、脊髓Dmean、心脏Dmean、心脏Dmax、心脏V30、心脏V40、心脏V60差异均存在统计学意义(P < 0.01)。结论 胸段食管癌患者行累及野照射与扩大野比较,可降低正常器官的受照剂量,从而降低放射性损伤风险。  相似文献   
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目的 分析重庆市肺癌发病死亡和疾病负担归因于被动吸烟的情况,为开展肺癌防治提供建议。 方法 肺癌死亡个案数据来源于2019年重庆市肿瘤登记报告系统,被动吸烟率来自2013年重庆市慢性病及危险因素监测。计算人群归因危险度百分比(population attributable risk percent, PAR%)、被动吸烟导致的肺癌发病、死亡和疾病负担。采用Excel 2010与SPSS 25.0进行统计分析,率的比较采用χ2检验。 结果 2013年30岁及以上成年人被动吸烟率为52.37%。2019年重庆市30岁及以上人群肺癌发病率与标化发病率分别为118.44/10万与80.83/10万,死亡率与标化死亡率分别为96.51/10万、63.58/10万。肺癌发病率和死亡率归因于被动吸烟的PAR%分别为19.76和19.04,归因发病率与归因标化发病率分别为23.41/10万和16.34/10万,归因死亡率与归因标化死亡率分别为18.38/10万和12.40/10万。2019年重庆市30岁及以上肺癌早死所致寿命损失年率(years of life lost,YLL)、残疾所致寿命损失年率(years lived with disability,YLD)、调整伤残寿命损失年率(disability adjusted life year,DALY)分别为21.16‰、0.31‰、21.47‰,YLL率、YLD率、DALY率归因于被动吸烟的PAR%分别为21.16、19.76和20.49,归因YLL率为4.34‰,归因YLD率为0.06‰,归因DALY率为4.40‰。 结论 2019年重庆市30岁及以上人群肺癌发病率、死亡率、YLL率、DALY率高,被动吸烟率高,肺癌归因于被动吸烟的疾病负担重,应加强落实控烟工作。  相似文献   
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Abstract

Can a single fiber of amphibole asbestos increase the risk of lung cancer or malignant mesothelioma (MM)? Traditional linear no-threshold (LNT) risk assessment assumptions imply that the answer is yes: there is no safe exposure level. This paper draws on recent scientific progress in inflammation biology, especially elucidation of the activation thresholds for NLRP3 inflammasomes and resulting chronic inflammation, to model dose-response relationships for malignant mesothelioma and lung cancer risks caused by asbestos exposures. The modeling integrates a physiologically based pharmacokinetics (PBPK) front end with inflammation-driven two-stage clonal expansion (I-TSCE) models of carcinogenesis to describe how exposure leads to chronic inflammation, which in turn promotes carcinogenesis. Together, the combined PBPK and I-TSCE modeling predict that there are practical thresholds for exposure concentration below which asbestos exposure does not cause chronic inflammation in less than a lifetime, and therefore does not increase chronic inflammation-dependent cancer risks. Quantitative examples using model parameter estimates drawn from the literature suggest that practical thresholds may be within about a factor of 2 of some past exposure levels for some workers. The I-TSCE modeling framework explains previous puzzling aspects of asbestos epidemiology, such as why age at first exposure is a better predictor of lifetime MM risk than exposure duration. It may be a valuable tool for risk analysts when LNT assumptions are not justified due to inflammation response thresholds mediating dose-response relationships.  相似文献   
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IntroductionThere is a growing interest in physical activity in relation to recovery after surgery. One important aspect of measuring recovery after surgical procedures is postoperative complications. The aim of this study was to determine if there is an association between the preoperative level of habitual physical activity and postoperative complications in patients undergoing elective surgery for colorectal cancer.Materials and methods115 patients scheduled for elective surgery due to colorectal cancer between February 2014 and September 2015 answered a questionnaire regarding physical activity and other baseline variables. Physical activity was assessed using the Saltin-Grimby physical activity level scale. Complications within 30 days after surgery were classified according to Clavien-Dindo, and the Comprehensive Complications Index (CCI) was calculated. Primary outcome was difference in CCI and key secondary outcome was risk for CCI ≥20.ResultsPhysically inactive individuals had a CCI that was 12 points higher than individuals with light activity (p = 0.002) and 17 points higher than regularly active individuals (p = 0.0004). Inactive individuals had a relative risk for a CCI ≥20 that was 65% higher than for individuals reporting light activity (95% confidence interval (CI) for relative risk (RR) = 1.1–2.5) and 338% higher than for regularly active individuals (95% CI for RR = 2.1–9.4).ConclusionSelf-assessed level of habitual physical activity before colorectal cancer surgery was associated with fewer postoperative complications measured with CCI, in a dose-response relationship.  相似文献   
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Pressure ulcers (PUs) are a serious health care problem for nursing home residents and a key quality metric for regulators. Three initiatives were introduced at a 128‐bed facility to improve PU prevention. First, a Quality Assurance and Performance Improvement project and a Root Cause Analysis were conducted to improve the facility's wound care programme. Second, a digital wound care management solution was adopted to track wound management. Third, the role of skin integrity coordinator was created as a central point of accountability for wound care‐related activities and related performance metrics. Improvements in PU prevention were tracked using Centers of Medicare and Medicaid data, specifically (a) the percentage of long‐stay high‐risk residents with PUs and (b) the percentage of short‐stay residents with PUs that are new or have worsened. PU prevalence for long‐stay high‐risk residents was 12.99% (Q4 2016), and upon implementation of these initiatives, the facility saw continued reductions in PU prevalence to 2.9% (Q4 2017), while PUs for short‐stay residents were maintained at zero throughout this period. This study highlights the power of effective management combined with real‐time data analytics, as enabled by digital wound care management, to make significant improvements in health care delivery.  相似文献   
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ObjectivesTo identify factors associated with 30-day all-cause readmission rates in surgical patients discharged to skilled nursing facilities (SNFs), and derive and validate a risk score.DesignRetrospective cohort.Setting and participantsPatients admitted to 1 tertiary hospital's surgical services between January 1, 2011, and December 31, 2014 and subsequently discharged to 110 SNFs within a 25-mile radius of the hospital. The first 2 years were used for the derivation set and the last 2 for validation.MethodsData were collected on 30-day all cause readmissions, patient demographics, procedure and surgical service, comorbidities, laboratory tests, and prior health care utilization. Multivariate regression was used to identify risk factors for readmission.ResultsDuring the study period, 2405 surgical patients were discharged to 110 SNFs, and 519 (21.6%) of these patients experienced readmission within 30 days. In a multivariable regression model, hospital length of stay [odds ratio (OR) per day: 1.03, 95% confidence interval (CI) 1.02-1.04], number of hospitalizations in past year (OR 1.24 per hospitalization, 95% CI 1.18-1.31), nonelective surgery (OR 1.33, 95% CI 1.18-1.65), low-risk service (orthopedic/spine service) (OR 0.32, 95% CI 0.25-0.42), and intermediate-risk service (cardiothoracic surgery/urology/gynecology/ear, nose, throat) (OR 0.69, 95% CI 0.53-0.88) were associated with all-cause readmissions. The model had a C index of 0.71 in the validation set. Using the following risk score [0.8 × (hospital length of stay) + 7 × (number of hospitalizations in past year) +10 for nonelective surgery, +36 for high-risk surgery, and +20 for intermediate-risk surgery], a score of >40 identified patients at high risk of 30-day readmission (35.8% vs 12.6%, P < .001).Conclusions/ImplicationsAmong surgical patients discharged to an SNF, a simple risk score with 4 parameters can accurately predict the risk of 30-day readmission.  相似文献   
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《Clinical therapeutics》2019,41(5):943-960.e4
PurposePatients’ perceptions of benefit–risk are essential to informing the regulatory process and the context in which potential therapies are evaluated. To bring this critical information to regulators, Cure SMA launched a first-ever Benefit-Risk Survey for spinal muscular atrophy (SMA) to characterize decision-making and benefit–risk trade-offs in SMA associated with a potential therapy. We hypothesized that risk tolerance would be correlated with SMA type/severity and disease progression. This article presents the results of a benefit–risk survey to enhance understanding of how patients with SMA and caregivers evaluate specific benefits and risks associated with potential therapies.MethodsAffected adults, representing all SMA types (I–IV) within the Cure SMA database, and caregivers of affected individuals of all ages/types were invited via e-mail to participate. Best–worst scaling (BWS) was used to assess participants’ priorities on benefit–risk trade-offs, as it provides higher discrimination and importance scaling among tested attributes. Twelve potentially clinically meaningful treatment benefits and 11 potential risks (ranging in severity and immediacy) were tested. Multiple factors were correlated with individual responses, including: SMA type/disease severity, stage of disease, respondent type, sex, and quality of life/level of independence (current and expected). Survey respondents were also evaluated for "risk-taking attitudes."FindingsA total of 298 responses were evaluated (28% affected adults and 72% caregivers, mostly parents). Most respondents were diagnosed >5 years ago (67.3%), with 22.1% SMA type I, 45.6% SMA type II, and 27.9% SMA type III. No strong correlation was found between risk tolerance and SMA type, stage of disease progression, respondent type, sex, quality of life assessment, or rated levels of independence. Irrespective of SMA type, respondents consistently rated the following risks, associated with a potential treatment, as "least tolerable": life-threatening allergic reactions; 1 in 1000 risk of life-threatening side effects leading to possible organ failure; or worsening quality of life. Furthermore, all SMA type respondents rated these risks as "most tolerable": invasive mode of treatment administration (including need for general anesthesia); side effect of dizziness; and other common side effects such as nausea, vomiting, loss of appetite, headaches, back pain, or fatigue.ImplicationsWith the approval of the first SMA treatment, these findings offer a unique opportunity to assess and characterize baseline risk-tolerance in SMA against which to evaluate future SMA treatment options. Although differences had been expected in risk tolerance among respondents based on disease baseline and certain patient attributes, this was not observed. Survey results should inform future SMA drug development and benefit–risk assessments.  相似文献   
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