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Summary

Chick embryos were exposed to sinusoidally oscillating 50 Hz magnetic fields during their first 2 days of development. In the first series of experiments magnetic field strengths of 0·1, 0·3, 1 and 10 A/m were used. The percentage of abnormal embryos (%AE) was 16 per cent in the sham-exposed control group. %AE was increased at 1 A/m (29 per cent) and 10 A/m (32 per cent), but not at 0·1 A/m (16 per cent) or 0·3 A/m (14 per cent). In the second series of experiments field strengths of 0·4, 0·6, 0·9 and 1·35 A/m were used. %AE was 17 per cent in the control group, 10 per cent at 0·4 A/m, 19 per cent at 0·6 A/m, 17 per cent at 0·9 A/m and 36 per cent at 1·35 A/m. Only the 1·35 A/m group was significantly different from the controls. The results of this study suggest that exposure of chick embryos to a 50 Hz magnetic field causes abnormal development, and that no abnormalities are induced below a threshold between 0·9 and 1 A/m.  相似文献   
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An in vitro degradation study of three bioresorbable glass fiber-reinforced poly(l-lactide-co-dl-lactide) (PLDLA) composites was carried out in simulated body fluid (SBF), to simulate body conditions, and deionized water, to evaluate the nature of the degradation products. The changes in mechanical and chemical properties were systematically characterized over 52 weeks dissolution time to determine the degradation mechanism and investigate strength retention by the bioresorbable glass fiber-reinforced PLDLA composite. The degradation mechanism was found to be a combination of surface and bulk erosion and does not follow the typical core-accelerated degradation mechanism of poly(α-hydroxyacids). Strength retention by bioresorbable glass fiber-reinforced PLDLA composites can be tailored by changing the oxide composition of the glass fibers, but the structure–property relationship of the glass fibers has to be understood and controlled so that the phenomenon of ion leaching can be utilized to control the degradation rate. Therefore, these high performance composites are likely to open up several new possibilities for utilizing resorbable materials in clinical applications which could not be realized in the past.  相似文献   
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Aims: In this study, we highlight the identities and actions of women with a problem-drinking relative by analysing autobiographies of women born between the 1920s and the 1950s. We ask how women describe their relationship and the problems arising because of a significant other’s drinking and how they cope with these problems. Methods: In the analysis, we pay attention to the power dynamics between family members. We, first, trace what kind of positions or identities the protagonists take in relation to the drinker. Second, we examine what kinds of harms and emotional reactions significant other’s drinking causes. Third, we consider how writers identify or take distance from events described in the autobiographies. Findings: Our analysis reveals four main identities and coping strategies: the positions of victim, helper, boundary setter and fighter. The victim and helper positions often entail women’s weakness and oppressed role, while the positions of boundary setter and fighter express women’s own power and reflexivity in action. Conclusions: Knowledge of the identities and coping strategies is important for understanding the power aspects of a relationship and developing appropriate support for women suffering from family member’s drinking.  相似文献   
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We report two cases of louse‐borne relapsing fever (LBRF) in young Somali asylum seekers having recently arrived to Finland. They had sought medical attention for a febrile illness. Blood smears were examined for suspected malaria, but instead, spirochete shaped bacteria were observed. The bacteria were confirmed as Borrelia recurrentis by PCR and sequencing. The patients survived, but their treatment was complicated by Jarisch–Herxheimer reaction. We conclude that LBRF must be considered as a diagnostic option in febrile refugees also in the northernmost parts of Europe.  相似文献   
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In a recent issue of Neuroethics, I considered whether the notion of human dignity could help us in solving the moral problems the advent of the diagnostic category of minimally conscious state (MCS) has brought forth. I argued that there is no adequate account of what justifies bestowing all MCS patients with the special worth referred to as human dignity. Therefore, I concluded, unless that difficulty can be solved we should resort to other values than human dignity in addressing the moral problems MCS poses. In his new book Christopher Kaczor criticizes the argument I put forward. Below, I respond to Kaczor’s criticism. I maintain that the considerations he presents do not undermine my argument nor succeed in providing adequate justification for the view that all MCS patients possess the worth referred to as human dignity.  相似文献   
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