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In malignant hyperthermia, myophosphorylase reaction shows characteristic changes that take place within minutes: (1) a generally strongly weakened reaction; (2) numerous negatively reacting fibres; (3) frequently, fibre sections that show spotty and/or striatal weak or negative reactions and fibre sections with strong striatal reactions with relatively narrow sarcomere spacings (a "sign of hypercontraction"). Obviously, the morphological findings that show characteristic "striated fibres" are typical of the malignant hyperthermia syndrome! It is important to note that the muscular fibres showing such changes are, as a rule, inconspicuous when using other stains and reactions. These pathological myophosphorylase reactions were observed in five deceased patients (one independently of anaesthesia after an extended walk) and in 19 pigs (18 times after halothane testing and once in an experimental animal with clinical evidence of the presence of malignant hyperthermia). These reactions were not noted in pigs with negative halothane reactivity or prior to halothane testing. They were also not seen in a large number of very different healthy and diseased control and reference cases from our biopsy and autopsy material. Myophosphorylase reaction enables convincing demonstration of malignant hyperthermia, past or present. Hence, it is possible to elucidate puzzling deaths or verify apparently clear death occurring during or subsequent to anaesthesia or simply following stress ("human stress syndrome"). Many of these deaths doubtlessly escape the attention of clinicians using the usual morphological examination methods. However, the reaction cannot be used to identify potential victims.  相似文献   
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Presidents traditionally have had great success when nominating justices to the Supreme Court, with confirmation being the norm and rejection being the rare exception. While the confirmation process usually ends with the nominee taking a seat on the Court, however, there is a great deal of variance in the amount of time it takes the Senate to act. To derive a theoretical explanation of this underlying dynamic in the confirmation process, we draw on a spatial model of presidential nominations to the Court. We then employ a hazard model to test this explanation, using data on all Supreme Court nominations and confirmations since the end of the Civil War. Our primary finding is that the duration of the confirmation process increases as the ideological distance between the president and the Senate increases. We also find evidence that suggests that the duration increases for critical nominees and chief justices and decreases for older nominees, current and previous senators, and nominees with prior experience on state and federal district courts .  相似文献   
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Mexican American youth are at greater risk of school failure than their peers. To identify factors that may contribute to academic success in this population, this study examined the prospective relationships from 5th grade to 7th grade of family (i.e., human capital [a parent with at least a high school education], residential stability, academically and occupationally positive family role models, and family structure) and individual characteristics (i.e., externalizing symptoms, bilingualism, gender, and immigrant status) to the academic performance of 749 Mexican American early adolescents (average age = 10.4 years and 48.7% were girls in 5th grade) from economically and culturally diverse families as these youth made the transition to junior high school. Results indicated that while controlling for prior academic performance, human capital and positive family role models assessed when adolescents were in 5th grade positively related to academic performance in 7th grade. Further, being a girl also was related to greater 7th grade academic success, whereas externalizing symptoms were negatively related to 7th grade academic performance. No other variables in the model were significantly and prospectively related to 7th grade academic performance. Implications for future research and interventions are discussed.  相似文献   
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Some Aboriginal youth are at disproportionate risk of using substances and developing abuse and dependence disorders. However, not all Aboriginal youth misuse substances and limited research has examined the protective factors conferring against substance use among these youth. The present study aimed to identify protective factors related to the alcohol use trajectories from early adolescence to emerging adulthood among off-reserve Canadian Aboriginal youth. Participants (N = 330; 50.3% male) aged 12–23 were selected from cycles 2–7 of Statistics Canada’s NLSCY. Multilevel modeling was employed to identify protective factors for two constructs of alcohol use. Participation in weekly activities and optimism were found to be protective for both the frequency of alcohol use and heavy drinking trajectories. Attendance of religious services was also found to be protective for heavy drinking behaviors. In contrast, positive peer relationships were a risk factor for frequency of alcohol use, but not heavy drinking. The results provide preliminary evidence of important developmental factors to integrate into substance use intervention programs targeting Aboriginal youth.  相似文献   
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In the US, an emergent cultural icon of resistant agriculture, the agrarian heroine, attests to growing popular interest in first-generation women farmers. Drawing on practice theory, historical geographical materialism, intersubjective ethnography and feminist scholarship, this ethnography focusses on three first-generation women farmers growing organic vegetable crops for the Chicago market, with critical attention to the body, the land and their uses. By applying permaculture’s theory of ‘the edge’ anthropologically, this study explores the work these women do to cultivate relational spaces that promote fluidity, diversity and solidarity in opposition to industrial agriculture and the homogenising forces of globalisation. The portraits that emerge problematise popular representations of first-generation women farmers.  相似文献   
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