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121.
The relation between occupational factors and pancreatic cancer has been studied by two different approaches: a population based case-control study with two series of controls and a retrospective cohort study based on register data. With both approaches, some support was found for an association with occupational exposure to petroleum products. Associations were also indicated with exposure to paint thinner (case-control study) and work in painting and in paint and varnish factories (cohort study), for exposure to detergents, floor cleaning agents, or polish (case-control study) and with floor polishing or window cleaning (cohort study), and for exposure to refuse (case-control study) and work in refuse disposal plants (cohort study).  相似文献   
122.

Background  

Experiencing or being at risk of adverse reactions to certain food items is a common health issue, especially among children and adolescents. Research has shown that living with the risk of food reactions and always having to take measures to avoid certain food in one's diet has a negative impact on quality of life. The aim of this study was to illuminate adolescents' experiences of being food hypersensitive.  相似文献   
123.
The in vitro activities of five cephalosporin antibiotics against 121 strains of salmonellae were compared. Cefamandole and cefaclor were more potent than cefazolin, and these three drugs were more active than cephalothin and cephalexin.  相似文献   
124.
OBJECTIVES: The aim was to survey the rate and cause of cancellations of planned cardiac operations at a Swedish clinic during 1999, and to study how the patients were affected. DESIGN: Questionnaires were distributed to 74 patients who had their operations cancelled. Their mood after discharge was measured with The Hospital Anxiety and Depression scale. Ninety-three patients, who were operated on without postponement, served as controls. RESULTS: Sixty-one percent of the patients in the cancellation group reacted negatively, especially if the reason for cancellation was organizational (P = 0.03). The women in the cancellation group had a significantly higher degree of depression than men (P = 0.01) and both women (P = 0.02) and men (P = 0.003) in the control group. Most of the patients, however, were satisfied with the nursing staff's reception and information. CONCLUSIONS: The patients reacted negatively to the cancellation, especially if it had organizational reasons. Women subjected to cancellation had a significantly higher degree of depression than other patients. To be avoided, organizational and medical problems must be identified in time. One way to do this is to introduce a preadmission nurse clinic.  相似文献   
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This study examines the intra-individual stability of cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) over 2 years in 83 patients with mild cognitive impairment (MCI) and 17 cognitively healthy control individuals. All participants underwent clinical and neuropsychological evaluation and lumbar puncture at baseline and after 2 years at a university hospital memory clinic. CSF was analyzed for total tau (T-tau), phospho-tau(181) (P-tau(181)) and amyloid-beta(1-42) (Abeta(1-42)). During the 2-year observational time, 12 MCI patients progressed to AD and 3 progressed to vascular dementia, while 68 remained stable. Baseline T-tau and P-tau(181) levels were elevated in the MCI-AD group as compared to the stable MCI patients and the control group (p<0.01), while baseline Abeta(1-42) levels were lower (p<0.001). Stable MCI patients were biochemically indistinguishable from controls. The biomarker levels at baseline and after 2 years showed Pearson R values between 0.81 and 0.91 (p<0.001) and coefficients of variation of 7.2 to 8.7%. In conclusion, intra-individual biomarker levels are remarkably stable over 2 years. Thus, even minor biochemical changes induced by treatment against AD should be detectable using these biomarkers, which bodes well for their usefulness as surrogate markers for drug efficacy in clinical trials.  相似文献   
128.
Objective: We studied mortality during long-distance ski races in Sweden. Design: The cohort comprised all subjects who participated in ski races during the Vasaloppet week from 1970 through 2005. All deaths during the races were identified and compared with the corresponding expected numbers based on national death rates. Results: In total, 698 102 starters generated altogether 581 person-years of skiing. Overall, 13 deaths occurred compared with 1.68 expected during the skiing time, yielding a standardized mortality ratio (SMR) of 7.7 [95% confidence interval (CI) 4.1-13.2]. Twelve of the deaths were caused by cardiovascular disease (SMR=22.1, 95% CI 11.4-38.6). Interviews of relatives revealed that two to four victims had medical conditions of the sort that they probably would have been recommended to avoid participation for medical reasons had they consulted a physician. Conclusion: Our study showed a clearly increased risk of acute mortality during long-distance skiing. However, as physically active people spend only a minority of their time in races, in that population the short-term excess mortality during these periods is by far outweighed by the long-term protective effects of exercise on mortality.  相似文献   
129.
BACKGROUND: Results from apparently conclusive meta-analyses may be false. A limited number of events from a few small trials and the associated random error may be under-recognized sources of spurious findings. The information size (IS, i.e. number of participants) required for a reliable and conclusive meta-analysis should be no less rigorous than the sample size of a single, optimally powered randomized clinical trial. If a meta-analysis is conducted before a sufficient IS is reached, it should be evaluated in a manner that accounts for the increased risk that the result might represent a chance finding (i.e. applying trial sequential monitoring boundaries). METHODS: We analysed 33 meta-analyses with a sufficient IS to detect a treatment effect of 15% relative risk reduction (RRR). We successively monitored the results of the meta-analyses by generating interim cumulative meta-analyses after each included trial and evaluated their results using a conventional statistical criterion (alpha = 0.05) and two-sided Lan-DeMets monitoring boundaries. We examined the proportion of false positive results and important inaccuracies in estimates of treatment effects that resulted from the two approaches. RESULTS: Using the random-effects model and final data, 12 of the meta-analyses yielded P > alpha = 0.05, and 21 yielded P alpha = 0.05. The monitoring boundaries eliminated all false positives. Important inaccuracies in estimates were observed in 6 out of 21 meta-analyses using the conventional P 相似文献   
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