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In this report, we will describe the first case of obsessive-compulsive behaviour following oral corticosteroid treatment in a 75-year old adult male patient with pulmonary disease, but without previous psychiatric symptoms or organic brain disorder. We will also discuss the clinical and pathophysiological considerations.  相似文献   
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BACKGROUND: The Program on the Surgical Control of the Hyperlipidemias (POSCH), a secondary intervention trial, was the only lipid/atherosclerosis randomized clinical trial that used a surgical modality--partial ileal bypass. POSCH provided solid evidence for the clinical and arteriographic benefits of lipid profile normalization. Few longterm followup reports have been published in this field. This report concerns overall mortality, the primary endpoint of POSCH, with a mean followup of 18 years (range 15.5 to 23.0 years). STUDY DESIGN: Overall mortality data were compiled from reports to the POSCH clinics, followup telephone calls, death certificates, and the US National Death Index. RESULTS: There were 144 deaths in the control group (n = 417) and 120 deaths in the intervention group (n = 421), using intent-to-treat analysis. The risk reduction in the intervention group was 0.201 (20%); the risk ratio was 0.799, or 0.8 (95% confidence intervals, 0.628 to 1.018, p = 0.07). The proportion of patients alive was 65.7% in the control group and 72.0% in the intervention group, for a difference of 6.3% in the intervention group (p = 0.05). Kaplan-Meier survival analysis (p = 0.046) and disease-free intervals analysis at 70% survival (p < 0.001) were confirmatory. The gain in life expectancy in the intervention group was 2.7 years. CONCLUSIONS: Longterm followup POSCH data demonstrate that lipid profile normalization will decrease overall mortality and will maintain a persistent and constant increase in life expectancy.  相似文献   
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Malignant gliomas are the most prevalent type of primary brain tumor in adults. Despite progress in brain tumor therapy, the prognosis of malignant glioma patients remains dismal. The median survival of patients with glioblastoma muhiforme, the most common grade of malignant glioma, is 10-12 months. Conventional therapy of surgery, radiation and chemotherapy is largely palliative. Essentially, tumor recurrence is inevitable. Salvage treatments upon recurrence are palliative at best and rarely provide significant survival benefit. Therapies targeting the underlying molecular pathogenesis of brain tumors are urgently required. Common genetic abnormalities in malignant glioma specimens are associated with aberrant activation or suppression of cellular signal transduction pathways and resistance to radiation and chemotherapy.  相似文献   
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BACKGROUND: A fairly immediate reduction in angina pectoris symptoms after cholesterol lowering has been described. Our previous findings in rabbits and in a four-patient human pilot study indicated the existence of an RBC membrane barrier to oxygen (O2) transport in the presence of hypercholesterolemia. Our current objective was to determine whether, and to what extent, the plasma cholesterol concentration is an influencing factor in RBC O2 release and cellular O2 availability. STUDY DESIGN: In an unique O2 diffusion analysis system, blood samples from 100 patients referred for lipid modification were analyzed. After 1 to 2 minutes of mixing in our diffusion analysis system, the next 1 to 2 minutes of circulation is comparable with 1 to 2 seconds of myocardial capillary flow. RBC O2 diffusion was defined by the depletion rate of total O2 content in blood from full O2 saturation (98%) to desaturation (approximately 60%). Relative tissue O2 availability was defined as the percentage decrease in O2 availability between the high-cholesterol group and the low-cholesterol group. RESULTS: The 100 patients were divided almost equally into two groups on the basis of plasma cholesterol ranges of 175 to 229 mg/dL (n=49) and 230 to 299 mg/dL (n = 51). The mean cholesterol concentrations and percentage increases in the high-cholesterol group over the low-cholesterol group were: for plasma, 206 +/- 0.3 and 256 +/- 0.4 mg/dL, 24.3% (p < 0.001); for RBCs, 93 +/- 0.2 and 106 +/- 0.2mg/dL, 14.0% (p < 0.001); and for RBC membranes, 41 +/- 0.1 and 54 +/- 0.2mg/dL, 31.7% (p < 0.001). The blood O2 diffusion curves were distinctly different between the high- and the low-cholesterol groups (p < 0.05). Blood O2 diffusion, defined by the blood O2 diffusion curves, was inversely proportional to the plasma, RBC, and RBC-membrane cholesterol concentrations. The relative tissue O2 availability, after a circulation period of more than 3 minutes in the diffusion system, showed a decrease of 17.5% (p < 0.05) between the plasma cholesterol groups. In comparing the two plasma cholesterol concentration extremes of less than 200mg/dL (n= 14) and greater than 275 mg/dL (n= 11) after a circulation period of more than 3 minutes in the diffusion system, we found a decrease in relative tissue O2 availability of 35.8% (p < 0.05). CONCLUSIONS: The plasma cholesterol concentration may be an influencing factor in RBC-membrane cholesterol content, which, in turn, may regulate RBC-membrane O2 transport, RBC O2 release, and cellular O2 availability. The implications of this work include the addition of angina pectoris control to the indications for appropriate lipid modification and the development of an in vitro blood stress test to replace patient cardiac stress testing.  相似文献   
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Quantifying the relationship between changes in lipid variables and clinical endpoints has been difficult. We studied the predictive value of various lipid variables on three endpoints in the Program on the Surgical Control of the Hyperlipidemias (POSCH): overall mortality, coronary heart disease (CHD) mortality, and CHD mortality and confirmed nonfatal myocardial infarction (MI) combined. We measured lipid variables for the annual visits from baseline to 5 years for actual follow-up values, actual and percentage differences between baseline and follow-up values, as well as the parameters comparing baseline only to 5 years for actual differences, percentage differences, and the ratio of baseline to 5 years. The lipid variables included were total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, triglycerides, and the LDL cholesterol/HDL cholesterol ratio. The analytic method used was that of Cox regression, with age and sex as secondary covariates, and each lipid or ratio of lipids as the primary (univariate) covariate. As a result, 108 univariate Cox regressions were conducted. The combined findings for the control and the intervention groups are presented. The number of events for the combined group were: overall mortality, 190; CHD mortality, 119; and CHD mortality and confirmed nonfatal MI, 262. The highest hazard ratios were found for the lipid variable of the LDL cholesterol/HDL cholesterol ratio (e.g. 1.196 for a 1-unit increase). Only for the combined endpoint of CHD mortality and confirmed nonfatal MI was there a substantial number of statistically significant relationships (P<0.01) of lipid variables and parameters of assessment.  相似文献   
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Ambulatory blood pressure monitoring (ABPM) in adults is proving to be useful. The aim of this study was to determine if ABPM is accurate in the lower blood pressure range encountered in children and, equally important, whether it is acceptable to children. Thirty one children, between the ages of 6 and 18 years, were assessed using an ambulatory blood pressure monitor that uses an auscultatory method. Blood pressure was measured in the contralateral arm with a mercury sphygmomanometer and an oscillometric device at the beginning and end of the study for comparison. Over a blood pressure range of 90-130 mm Hg systolic and 40-80 mm Hg diastolic, a close agreement was found with the sphygmomanometer; the limits of agreement (+/- 2 SD) were 11.6 mm Hg for systolic blood pressure and 13.6 mm Hg for diastolic blood pressure. The bias was less than 1.0 mm Hg. The ambulatory device was worn by all patients for at least 16 hours with an average of 52 recordings per patient. The majority found the device comfortable to wear and were not woken from sleep.  相似文献   
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BACKGROUND: Unlike phenytoin, overdose from mephenytoin (CAS No. 50-12-4) is rare. A review of mephenytoin shows a number of differences from phenytoin, including structural, metabolic, pharmacodynamic, and toxicologic effects. Mephenytoin metabolism is also characterized by genetic polymorphism, which can result in prolonged elimination. Routine blood testing for phenytoin may show no interference from mephenytoin. Mephenytoin levels are not readily available nor clinically useful when they do become available; urine toxicology screen may be positive for barbiturates. CASE REPORT: A 26-year-old female overdosed on approximately 12 g of mephenytoin and an unknown amount of valproic acid. She became comatose, developing pulmonary aspiration and pancreatitis with fever. Her Intensive Care Unit treatment was prolonged with slow resolution over 10 days. A review of mephenytoin and comparison to phenytoin overdose is provided in the context of this case report.  相似文献   
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