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During 1988-1999 39 unstable fractures of the distal clavicle (Neer 2) were operated on in Oulu University Hospital. Kirschner wire (K-wire) fixation was used in 22 cases and a clavicular hook plate in 17. Shoulder symptoms and function were assessed using self-administered questionnaires devised by L'Insalata et al. (1997), and Constant scoring. Mean follow-up was 6.2 years in the K-wire fixation group and 2.0 years in the clavicular hook plate one. The mean L'Insalata scores were 91 in both groups (92% and 93% of the contralateral side) and the mean Constant scores 84 (95%) and 90 (96%) for K-wire fixation and the clavicular hook plate, respectively. Complications commonly occurred with K-wires, which migrated in 12 cases, resulting in loss of reduction in 7 and infection in 3, and 2 cases of non-union. In the clavicular hook plate group, there was 1 complication, a fracture of the clavicle, and 2 cases of non-union. We conclude that shoulder symptoms were reduced and function restored to an adequate level by both methods, but complications were unacceptably frequent when K-wires were used. The clavicular hook plate was better in this respect and it is therefore recommended.  相似文献   
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A total of 81 randomly selected elementary school teachers participated in two sampling campaigns conducted 2 weeks apart during the winter. A 24-h sample collection was performed using personal and microenvironmental sampling from homes, and an 8-h sample collection was performed from workplaces of the studied subjects. Filters were analyzed for particle mass, absorption coefficient of the filter, and for both total and viable microorganisms. Comprehensive questionnaire responses were collected from the teachers concerning weekly occurred symptoms during the previous 12-month period, and they filled in symptom diaries immediately after each sampling campaign concerning symptoms during the previous 24-h and 7-day periods. The effect of different recall periods on agreement between questionnaire responses was assessed. Factor analysis was used in order to identify factors explaining the pattern of correlations within the personal, home, and work measurements. Moreover, associations between personal, home, and work measurements of pollutants and symptoms were analyzed using general estimation equations. The recall period of 7 days seemed to provide the most reliable data for the health effect assessment. Information from the factor analysis may allow reduction of variables related to the exposure assessment, and better interpretation of results. Both personal exposure and concentrations of pollutants at home were more frequently associated with health symptoms than concentrations at work. In multipollutant analyses, absorbance coefficient was positively associated with eye symptoms, and total bacteria with both cough and blocked nose.  相似文献   
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Arachidonic acid metabolites, the eicosanoids, are key mediators of allergen-induced airway inflammation and remodeling in asthma. The availability of free arachidonate in cells for subsequent eicosanoid biosynthesis is controlled by phospholipase A(2)s (PLA(2)s), most notably cytosolic PLA(2)-alpha. 10 secreted PLA(2)s (sPLA(2)s) have also been identified, but their function in eicosanoid generation is poorly understood. We investigated the role of group X sPLA(2) (sPLA(2)-X), the sPLA(2) with the highest in vitro cellular phospholipolysis activity, in acute and chronic mouse asthma models in vivo. The lungs of sPLA(2)-X(-/-) mice, compared with those of sPLA(2)-X(+/+) littermates, had significant reduction in ovalbumin-induced infiltration by CD4(+) and CD8(+) T cells and eosinophils, goblet cell metaplasia, smooth muscle cell layer thickening, subepithelial fibrosis, and levels of T helper type 2 cell cytokines and eicosanoids. These data direct attention to sPLA(2)-X as a novel therapeutic target for asthma.  相似文献   
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Group II PLA2 has been implicated in inflammatory processes in both man and other animals and has been shown to be involved in inflammatory conditions, such as arthritis and sepsis. Transgenic mice expressing the human group II PLA2 gene have been generated using a 6.2-kb genomic fragment. These mice express the group II PLA2 gene abundantly in liver, lung, kidney, and skin, and have serum PLA2 activity levels approximately eightfold higher than nontransgenic littermates. The group II PLA2 transgenic mice reported here exhibit epidermal and adnexal hyperplasia, hyperkeratosis, and almost total alopecia. The chronic epidermal hyperplasia and hyperkeratosis seen in these mice is similar to that seen in a variety of dermatopathies, including psoriasis. However, unlike what is seen with these dermatopathies, no significant inflammatory-cell influx was observed in the skin of these animals, or in any other tissue examined. These mice provide an important tool for examining group II PLA2 expression, and for determining the role of group II PLA2 in normal and disease physiology. They serve as an in vivo model for identifying inhibitors of group II PLA2 activity and gene expression.  相似文献   
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Introduction: We evaluated whether there are constant preoperative alterations in nonlinear R–R interval dynamics that associate with the risk of postoperative atrial fibrillation in patients with preserved left ventricular function. Methods: We analyzed mean normal‐to‐normal R–R intervals, short‐term scaling exponent of detrended fluctuation analysis (DFA α1), approximate entropy and entropy of symbolic dynamics (SymDyn En) from 10‐minute ECG recordings during rest, paced breathing, and passive tilt performed 1 day before surgery in 67 elective coronary artery bypass grafting patients. Results: Nineteen patients developed postoperative atrial fibrillation. The preoperative DFA α1 was constantly lower in patients developing postoperative atrial fibrillation than in patients remaining in sinus rhythm (P = 0.016); during spontaneous breathing, the DFA α1 was 0.93 ± 0.33 in patients with atrial fibrillation and 1.13 ± 0.24 in patients with sinus rhythm. The entropy of symbolic dynamics was higher during the spontaneous breathing in patients with atrial fibrillation than in patients with sinus rhythm (4.72 ± 0.51 vs 4.36 ± 0.51, P = 0.012). Higher short‐term scaling exponent of detrended fluctuation analysis during the spontaneous breathing period reduced the risk of postoperative atrial fibrillation (OR 0.31 for an interquartile increase in DFA α1, 95% CI 0.13–0.78), while higher entropy of symbolic dynamics increased it (OR 3.16 for an interquartile increase in SymDyn En, 95% CI 1.23–8.10), independently of age and clinical risk factors. Conclusion: The preoperatively altered nonlinear R–R interval dynamics were independent predictors of postoperative atrial fibrillation and might become a useful tool for the risk assessment of atrial fibrillation.  相似文献   
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Background: Although high doses of ionizing radiation have long been linked to circulatory disease, evidence for an association at lower exposures remains controversial. However, recent analyses suggest excess relative risks at occupational exposure levels.Objectives: We performed a systematic review and meta-analysis to summarize information on circulatory disease risks associated with moderate- and low-level whole-body ionizing radiation exposures.Methods: We conducted PubMed/ISI Thomson searches of peer-reviewed papers published since 1990 using the terms “radiation” AND “heart” AND “disease,” OR “radiation” AND “stroke,” OR “radiation” AND “circulatory” AND “disease.” Radiation exposures had to be whole-body, with a cumulative mean dose of < 0.5 Sv, or at a low dose rate (< 10 mSv/day). We estimated population risks of circulatory disease from low-level radiation exposure using excess relative risk estimates from this meta-analysis and current mortality rates for nine major developed countries.Results: Estimated excess population risks for all circulatory diseases combined ranged from 2.5%/Sv [95% confidence interval (CI): 0.8, 4.2] for France to 8.5%/Sv (95% CI: 4.0, 13.0) for Russia.Conclusions: Our review supports an association between circulatory disease mortality and low and moderate doses of ionizing radiation. Our analysis was limited by heterogeneity among studies (particularly for noncardiac end points), the possibility of uncontrolled confounding in some occupational groups by lifestyle factors, and higher dose groups (> 0.5 Sv) generally driving the observed trends. If confirmed, our findings suggest that overall radiation-related mortality is about twice that currently estimated based on estimates for cancer end points alone (which range from 4.2% to 5.6%/Sv for these populations).  相似文献   
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