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Prevention Science - The effectiveness of bullying prevention programs has led to expectations that these programs could have effects beyond their primary goals. By reducing the number of victims...  相似文献   
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Background. Recently we reported on cerebral metabolic changes suggesting ischemia in piglets during nitroprusside-induced low-pressure CPB. We here investigated whether a mean arterial pressure (MAP) of 40–45 mmHg could provoke similar changes by a NO-independent intervention. Methods. Piglets underwent 60 minutes normothermic followed by 90 minutes hypothermic CPB. The LP-group (n=8) had MAP of 40–45 mmHg by phentolamine while the HP-group (n=8) had MAP of 60–80 mmHg by norepinephrine. Cerebral glucose, lactate, pyruvate and glycerol were determined. In the last two animals of each group, cerebral tissue was examined by electron microscopy. Results. Cerebral lactate was higher in the LP-group than the HP-group during normothermic CPB. Compared with baseline, cerebral glucose of the LP-group decreased whereas lactate/pyruvate-ratio, lactate and glycerol-concentrations increased during normothermic CPB. In the HP-group these parameters remained unchanged. Electron microscopy showed 31.2% and 8.3% altered mitochondria in the cortical micrographs taken from the LP- and the HP-group, respectively (p<0.001). Conclusion. MAP below 45 mmHg during CPB was associated with cerebral biochemical and morphological changes consistent with anaerobic metabolism and subcellular injury.  相似文献   
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INTRODUCTION: This study investigated whether two levels of mean arterial pressure (MAP) during cardiopulmonary bypass did influence per-operative fluid shifts. METHODS: Sixteen pigs underwent 60 minutes of normothermic cardiopulmonary bypass (CPB) followed by 90 minutes of hypothermic CPB. Eight animals had a MAP of 60-80mmHg by norepinephrine (HP group). Another 8 animals had a MAP of 40-45 mmHg by phentolamine (LP group). Blood chemistry, plasma/interstitial colloid osmotic pressures, plasma volume, fluid balance, fluid extravasation rate and tissue water content were measured or calculated. RESULTS: The plasma volume was significantly lower in the HP group compared with the LP group after 60 minutes of CPB. Net fluid balance was 0.18 (0.05) ml x kg(-1) x min(-1) in the HP group and 0.21 ml x kg(-1) x min(-1) in the LP group (P > 0.05) while fluid extravasation rate was 1.18 (0.5) and 1.13 (0.4) ml x kg(-1) x min(-1) in the HP group and the LP group during CPB (P > 0.05). CONCLUSION: Net fluid balance and fluid extravasation rate were similar in the animals with elevated and with lowered MAP during CPB.  相似文献   
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Previous studies have shown frequent mutations in the BRAF (V-raf murine sarcoma viral oncogene homolog B1) or NRAS (neuroblastoma RAS viral [V-ras] oncogene homolog) genes in cutaneous melanoma, but the relationship between these alterations and tumor cell proliferation has not been examined in human melanoma. In our study of 51 primary nodular melanomas and 18 paired metastases, we found mutations in BRAF (codon 600, previously denoted 599) in 15 primary tumors (29%) and eight metastases (44%). The figures for NRAS mutations were 27% and 22%, respectively. Mutations in BRAF and NRAS genes were mutually exclusive in all but one case, and were maintained from primary tumors through their metastases. Mutations, however, were not associated with tumor cell proliferation by Ki-67 expression, tumor thickness, microvessel density, or vascular invasion, and there were no differences in patient survival. Although BRAF and NRAS mutations are likely to be important for the initiation and maintenance of some melanomas, other factors might be more significant for proliferation and prognosis in subgroups of aggressive melanoma.  相似文献   
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The prevalence of eating disorders among 311 adults with mental retardation living in the West Coast of Norway was investigated. Reports stemming from a questionnaire completed by health workers were the data source. Diagnostic criteria adapted for persons with mental retardation were used. The main finding was that 27% of cases showed indices of an eating disorder. Among the eating disorders, binge-eating was the most prevalent. Incidence of anorexia nervosa was higher than that of the general population. Findings suggest that eating disorders are more prevalent in this population than in the general population.  相似文献   
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PURPOSE: In the present study, high-resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS (1)H NMR) spectroscopy was used to investigate changes in the metabolic profile of intact rat lenses after UVB irradiation of the eyes. METHODS: Three groups of Sprague-Dawley rats were exposed to UVB radiation at 2.5, 5.0, and 7.5 kJ/m(2). One eye was exposed, and the contralateral eye served as the control. One week after exposure, the lenses were removed and forward light-scattering was quantified. Thereafter, proton NMR spectra from the intact lenses were obtained. Relative changes in metabolite concentrations were determined. RESULTS: The lenses in all three groups showed significant increases in light-scattering after UVB irradiation. The high-quality HR-MAS (1)H NMR spectra permitted more than 30 different metabolites to be identified. UVB irradiation caused a significant decrease (P < 0.05) in concentrations of taurine, hypotaurine, tyrosine, phenylalanine, valine, myo-inositol, phosphocholine, betaine, succinate, and glutathione at all three UV doses. For glycine, glutamate, and lactate, significant decreases in concentration were observed at the two lowest UVR-B doses. The total amount of adenosine tri- and diphosphate and (ATP, ADP) decreased significantly and that of adenosine monophosphate AMP increased significantly at the two highest doses. Alanine was the only amino acid that increased after UVB irradiation. None of these metabolites exhibited a significant UVB dose-dependent relationship. CONCLUSIONS: This study demonstrates for the first time the potential of HR-MAS (1)H NMR spectroscopy as an analytical tool for use on intact lenses. Near-threshold UVR-B doses led to a generally significant decrease in water-soluble metabolites 1 week after exposure. The lack of dose-dependent changes in the metabolites indicates that repair processes during the first week after UVB irradiation overcome the immediate metabolic disturbances.  相似文献   
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Introduction  

The incidence and outcome of acute respiratory failure (ARF) depend on dysfunction in other organs. As a result, reported mortality in patients with ARF is derived from a mixed group of patients with different degrees of multiorgan failure. The main goal of the present study was to investigate patient outcome in single organ ARF.  相似文献   
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We tested the hypothesis that hyperbaric oxygen (HBO) alone and with chemotherapy (5-FU) attenuates tumor growth of DMBA-induced tumors in rats. Six series were performed: (1) Controls (air and vehicle 0.9% NaCl i.p.), (2) 5-FU (0.2 mg/kg i.p.), (3) HBO (2 bar for 90 min and vehicle), (4) HBO and 5-FU, (5) HBO (11 days) and air (next 12 days), (6) HBO (23 days). All treatments were applied on days 1, 4, 7, 10 (Series 1-4), as well as on days 14, 17 and 23 (Series 5-6). Tumor diameter increased by 76.7 and 41.2% in untreated controls and in the 5-FU group, respectively, after 10 days. Tumor size fell by 17-24.2% in the HBO groups and by 35.5% when combined with 5-FU (P < 0.05 compared to HBO). HBO treatment reduced the total number of blood vessels in the tumors. After completion of HBO treatment tumor size increased, but statistically insignificant, during the next 12 days.  相似文献   
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