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排序方式: 共有108条查询结果,搜索用时 15 毫秒
1.
电解铝厂职工恶性肿瘤死亡状况回顾性队列研究   总被引:1,自引:0,他引:1  
对某电解铝厂职工恶性肿瘤死亡情况进行了10年回顾性队列研究,以宁夏1990 ̄1992年人口年龄死亡专率为参比,计算了观察队列标化死亡比(SMR)、癌症比例死亡比(PMR和PCMR),观察组肺癌超出量尤为显著,SMR为190(P〈0.01),PCMR为171(P〈0.05)。  相似文献   
2.

Background

Congenital heart surgery has improved the survival of patients with even the most complex defects, but the long-term survival after these procedures has not been fully described.

Objectives

The purpose of this study was to evaluate the long-term survival of patients (age <21 years) who were operated on for congenital heart defects (CHDs).

Methods

This study used the Pediatric Cardiac Care Consortium data, a U.S.-based, multicenter registry of pediatric cardiac surgery. Survival analysis included 35,998 patients who survived their first congenital heart surgery at <21 years of age and had adequate identifiers for linkage with the National Death Index through 2014. Survival was compared to that in the general population using standardized mortality ratios (SMRs).

Results

After a median follow-up of 18 years (645,806 person-years), 3,191 deaths occurred with an overall SMR of 8.3 (95% confidence interval [CI]: 8.0 to 8.7). The 15-year SMR decreased from 12.7 (95% CI: 11.9 to 13.6) in the early era (1982 to 1992) to 10.0 (95% CI: 9.3 to 10.8) in the late era (1998 to 2003). The SMR remained elevated even for mild forms of CHD such as patent ductus arteriosus (SMR 4.5) and atrial septal defects (SMR 4.9). The largest decreases in SMR occurred for patients with transposition of great arteries (early: 11.0 vs. late: 3.8; p < 0.05), complete atrioventricular canal (31.3 vs. 15.3; p < 0.05), and single ventricle (53.7 vs. 31.3; p < 0.05).

Conclusions

In this large U.S. cohort, long-term mortality after congenital heart surgery was elevated across all forms of CHD. Survival has improved over time, particularly for severe defects with significant changes in their management strategy, but still lags behind the general population.  相似文献   
3.
BACKGROUND & AIMS: A population-based cohort from Copenhagen County comprising 1160 patients diagnosed with ulcerative colitis between 1962 and 1987 was followed-up until 1997 to describe survival and cause-specific mortality. METHODS: Observed vs. expected deaths were presented as standardized mortality ratio (SMR) with exact 95% confidence intervals (CI) calculated by using individually registered person-years at risk and Danish 1995 mortality rates. Cumulative survival curves were calculated. RESULTS: A total of 261 deaths occurred, not significantly different from the expected number of 249 (SMR, 1.05; 95% CI, 0.92-1.19). The median age at death among men was 70 years (range, 6-96 years) and among women 74 years (range, 25-96 years). Twenty-five deaths (9.6%) were caused by complications to ulcerative colitis, mostly infectious and cardiovascular postoperative complications. Patients older than 50 years of age at diagnosis and with extensive colitis showed an increased mortality within the first 2 years because of ulcerative colitis-associated causes. The mortality from colorectal cancer was not increased and that of cancer in general was significantly lower than expected: 50 vs. 71 (SMR, 0.70; 95% CI, 0.52-0.93). A significantly increased mortality from pulmonary embolism and pneumonia was found. Among women only, death from genitourinary tract diseases and suicide was significantly increased. CONCLUSIONS: Despite an overall normal life expectancy for patients with ulcerative colitis, patients >50 years of age and with extensive colitis at diagnosis had increased mortality within the first 2 years after diagnosis, owing to colitis-associated postoperative complications and comorbidity.  相似文献   
4.
For researchers, policymakers, and practitioners facing a new field, undertaking a systematic review can typically present a challenge due to the enormous number of relevant papers. A scoping review is a method suggested for addressing this dilemma; however, scoping reviews present their own challenges. This paper introduces the “scoping meta‐review” (SMR) for expanding current methodologies and is based on our experiences in mapping the field of consumer engagement in healthcare. During this process, we developed the novel SMR method. An SMR combines aspects of a scoping review and a meta‐review to establish an evidence‐based map of a field. Similar to a scoping review, an SMR offers a practical and flexible methodology. However, unlike in a traditional scoping review, only systematic reviews are included. Stages of the SMR include: undertaking a preliminary nonsystematic review; building a search strategy; interrogating academic literature databases; classifying and excluding studies based on titles and abstracts; saving the refined database of references; revising the search strategy; selecting and reviewing the full text papers; and thematically analyzing the selected texts and writing the report. The main benefit of an SMR is to map a new field based on high‐level evidence provided by systematic reviews.  相似文献   
5.
Introduction. The aim of this study was to clarify the interpretation of sensory-motor rhythm (SMR; 13–15 Hz) and beta (16–20 Hz) changes with respect to attention states.

Method. For this purpose, EEG was recorded from 11 participants during (a) a multiple object tracking task (MOT), which required externally directed attention; (b) the retention phase of a visuo-spatial memory task (VSM), which required internally directed attention and avoidance of sensory distraction; and (c) the waiting intervals between trials, which constituted a no-task-imposed control condition. The 2 active tasks were consecutively presented at 2 difficulty levels (i.e., easy and hard). Two analyses of variance were conducted on EEG log spectral amplitudes in the alpha (8–12 Hz), SMR, and beta bands from F3, F4, C3, C4 and P3, P4.

Results. The first 15 analysis compared the MOT to the VSM by difficulty levels and revealed a significant task effect (p < .0005) but no effect of difficulty. The results showed that externally directed attention (MOT) resulted in lower values than internally directed attention (VSM) in all three bands. The second analysis averaged the difficulty levels together and added the no-task-imposed reference condition. The results again showed a significant task effect that did not interact with site, hemisphere, or, more important, band. Post hoc tests revealed that both MOT and VSM produced significantly smaller means than the no-task-imposed condition. This pattern of log-amplitude means and the lack of task interaction with any other factor indicate that task-induced attention reduces EEG power in the same proportion across the 3 bands and the 6 channels studied.

Conclusions. These results contradict a frequent interpretation concerning the relationship between the brain's aptitude to increase low beta in neurofeedback programs and improved sustain attention capacities.  相似文献   
6.
Objective : To examine the trends of all‐cause natural mortality for people aged 15 years and over in a remote Australian Aboriginal community between 1996 and 2010. Methods : The annual population in the community by gender and age group was obtained from the Australian Bureau of Statistics (ABS). All known deaths and all records of start of renal replacement therapy (RRT) for renal failure were recorded between 1996 and 2010. Five‐year aggregated death rates were calculated and the changes in natural mortality over the interval were evaluated. Mortality was compared with those of the Northern Territory (NT) Indigenous and non‐Indigenous people as a whole from 1998 to 2006. Results : Rates of natural deaths were lower in the third interval 2006–2010 relative to the first interval 1996–2000, with higher, but more rapidly falling rates for females than males. Reductions were prominent for both sexes in the 65 and over age groups, but death rates in females of earlier middle age also trended lower. The trends applied whether or not the starting of RRT was considered as a natural death. There was a similar trend in rates of natural death in the aggregate Indigenous population of NT. Conclusions: The downward trends probably reflect improvements in risk factor status since the 1960s, all‐of‐life health interventions, as well as better chronic disease management in the last two decades. The higher death rates in females than males in this community remain unexplained, but the rapid rate of decline of female death rates predicts that this gap will soon be minimised.  相似文献   
7.
Objectives  The aim of this study was to compare the risk for cancers of A-bomb survivors in the ongoing life span study (LSS) with unexposed groups consisting of the entire populations of Hiroshima prefecture and neighboring Okayama prefecture. Methods  The subjects consisted of the Hiroshima group reported in LSS report 12 (LSS-H group) and a control group (the entire populations of Hiroshima and Okayama—HPCG and OPCG, respectively). We estimated the expected number of deaths due to all causes and to cancers of various causes among the exposed survivors of the Hiroshima bombing in the LSS report 12 who died in the follow-up interval at ages similar to those of people in Hiroshima and Okayama prefectures who were aged 0–34 years at the time of the bombing in 1945. We compared the standardized mortality ratio (SMR) of the LSS-H group to that of the HPCG and OPCG (SMR-H and SMR-O, respectively). Results  Even at low and very low dose categories, the SMR-H and SMR-O were significantly high for all deaths, all cancers, solid cancers, and liver cancers in male subjects, and for uterus and liver cancers in female subjects, respectively. The results show that, if the dose estimations of the dosimetry system 1986 (DS86) are correct, there are significantly increased risks of cancer among even survivors exposed to the very low dose level. Conclusions  The dose assumptions of DS86 have been criticized for underestimating doses in areas distant from the hypocenter. The contribution of residual radiation, ignored in LSS, and that of neutrons, underestimated by DS86, is suggested to be fairly high. An erratum to this article can be found at  相似文献   
8.
目的分析2002~2005年南岗区居民平均寿命和死亡原因,发现亟待解决的健康问题。方法收集人口资料和死亡资料,按蒋庆琅法编制寿命表,应用Exccel软件计算死因构成。结果南岗区2002~2005年人口期望寿命为75.99岁,接近世界先进国家水平。三类与动脉粥样硬化关系密切的疾病—心血管疾病、脑血管疾病、糖尿病合计死亡率达118.47/10万,占总死亡的比率为40.20%,居全死因的首位。结论预防控制心脑血管疾病以及糖尿病将极大地延长居民平均寿命,发现促使发病的地域性、特征性因素并加以阻断,将是流行病学研究的重大课题。  相似文献   
9.

Objectives

As part of the 2014–2019 cancer plan and in order to improve our knowledge of work-related cancers, we analysed the work-related laryngeal cancer risk situations identified in the French national occupational disease surveillance and prevention network (rnv3p) from 2001 to 2016.

Material and methods

This study focused on cases of work-related laryngeal cancer, which the expert physician considered to be directly related to exposure (intermediate or strong causal relationship). Demographic data, occupational exposure circumstances (hazards, occupation, business sector), non-occupational risk factors and the occupational physician's opinion concerning notification as an occupational disease were analysed.

Results

Two hundred forty-four cases of laryngeal cancer were registered between 2001 and 2016. One hundred and forty seven cases were considered to be work-related, with an intermediate or strong causal relationship in 87 cases. This exclusively male population had a median age of 59 years. Ninety-seven different forms of exposure were identified, including asbestos in 78 cases. The main business sectors concerned were specialized construction (14 cases) and metallurgy (7 cases). Occupational disease notification was recommended in 60 patients, corresponding to asbestos exposure in 80% of cases.

Conclusions

Asbestos is the laryngeal cancer risk factor most commonly reported in the network from 2001 to 2016. This study confirms the role of asbestos in laryngeal carcinogenesis. Laryngeal cancer may therefore need to be compensated as an occupational disease in France, as in other European countries.  相似文献   
10.
Kahn JM  Kramer AA  Rubenfeld GD 《Chest》2007,131(1):68-75
BACKGROUND: Transferring critically ill patients to other acute care hospitals may artificially impact benchmarking measures. We sought to quantify the effect of out-of-hospital transfers on the standardized mortality ratio (SMR), an outcome-based measure of ICU performance. METHODS: We performed a cohort study and Monte Carlo simulation using data from 85 ICUs participating in the acute physiology and chronic health evaluation (APACHE) clinical information system from 2002 to 2003. The SMR (observed divided by expected hospital mortality) was calculated for each ICU using APACHE IV risk adjustment. A set number of patients was randomly assigned to be transferred out alive rather than experience their original outcome. The SMR was recalculated, and the mean simulated SMR was compared to the original. RESULTS: The mean (+/- SD) baseline SMR was 1.06 +/- 0.19. In the simulation, increasing the number of transfers by 2% and 6% over baseline decreased the SMR by 0.10 +/- 0.03 and 0.14 +/- 0.03, respectively. At a 2% increase, 27 ICUs had a decrease in SMR of > 0.10, and two ICUs had a decrease in SMR of > 0.20. Transferring only one additional patient per month was enough to create a bias of > 0.1 in 27 ICUs. CONCLUSIONS: Increasing the number of acute care transfers by a small amount can significantly bias the SMR, leading to incorrect inference about ICU quality. Sensitivity to the variation in hospital discharge practices greatly limits the use of the SMR as a quality measure.  相似文献   
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