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Background: Stimulant drugs are the most commonly used treatments for attention-deficit/hyperactivity disorder (ADHD), although the mechanism of action of these drugs is still not entirely understood.Objective: The aim of this study was to investigate the effects of the psychostimulant drug methylphenidate (MPH) on regional cerebral blood flow (rCBF), electrical activity of the brain, and clinical symptoms in children with ADHD using single-photon emission computed tomography (SPECT), electroencephalography (EEG), and neuropsychological tests.Methods: In this prospective cohort study, pediatric outpatients received MPH for 3 months at a mean dose of 1 mg/kg · d (range, 0.5-1.5 mg/kg · d). They were then administered the Wechsler Intelligence Scale for Children-Revised, the Bender Visual-Motor Gestalt Test (BGT), EEG, and SPECT of the brain. The parents and/or teacher of each child were asked to complete the Conners' Parent Rating Scale (CPRS), the Conners' Teacher Rating Scale (CTRS), and the Turgay Diagnostic and Statistical Manual of Mental Disorders Fourth Edition-based Child and Adolescent Behavior Disorders Screening and Rating Scale (T-DSM-IV-S). All of the evaluations were performed at baseline and after 3 months of MPH treatment. Each child underwent a Stroop test as an activation method 15 minutes before the SPECT procedure.Results: Sixty patients were assessed for inclusion. Twenty-one children (18 boys [85.7%], 3 girls [14.3%]; mean [SD] age, 9.7 [1.7] years; range, 8-13 years) with a diagnosis of ADHD were included in and completed the study. Mean (SD) BGT scores before MPH treatment compared with after MPH treatment were significantly decreased (9.8 [4.2] vs 6.3 [3.4]; Z = -3.27; P = 0.001). After treatment with MPH, the visual SPECT results suggested that low rCBF was normalized in the right frontotemporal areas in 10 children with ADHD. After treatment, 12 patients (57.1%) had no change in EEG activity, 5 (23.8%) had improvement, and 4 (19.0%) had worsening activity. Patients who had improvement or no worsening on EEG after MPH treatment were associated with significant improvement after MPH treatment compared with before treatment in mean (SD) CTRS scores (25.9 [14.3] vs 35.0 [14.4]; P = 0.003), teachers' T-DSM-IV-S total score (25.1 [14.2] vs 38.4 [18.7]; P = 0.005), and CPRS scores (mothers scores: 29.7 [16.6] vs 42.6 [17.2], P = 0.002; fathers' scores: 29.4 [16.8] vs 41.9 [23.7], P = 0.004). No significant difference was found in these scores in the patients whose EEG findings showed deterioration after MPH treatment. The quantitative values for SPECT observed before treatment compared with those observed after 3 months of MPH treatment were not found to be significantly different in any areas of the brain.Conclusions: MPH use over 3 months was associated with improvement from baseline in visual-motor function and behavioral disorders in these children and adolescents with ADHD. However, no significant difference in rCBF or electrical activity in the brain was observed in this small study.  相似文献   
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Recently, anti-inflammatory and tissue protective effects of statins have been shown independent from its anti-hyperlipidemic effect. It has been shown that one of the statins, rosuvastatin, may reduce ischemia/reperfusion (I/R)-induced tissue injury in the brain, intestines, and heart. We planned an experimental study to evaluate the effect of rosuvastatin on I/R injury encountered after the detorsion of the testicular torsion. Rats were divided into three groups. In group 1, testis basal blood flow (basal value) was measured with LASER Doppler flowmeter (LDF). Testis was relocated into the scrotum without torsion. Two and 3 h after the basal measurement, testis was brought out from the same incision, and the second (second value) and third (third value) testicular blood flow measurements were done, respectively. In group 2, after the measurement of basal value testicular torsion was created. Second and third value measurements were obtained with LDF at the end of the 2 h of testicular torsion just before the detorsion and 1 h after detorsion. In group 3, same procedures in torsion/detorsion group were repeated in this group, but 10 mg/kg rosuvastatin was injected intraperitoneally 30 min before detorsion. Second values in groups 2 and 3 were significantly lower than group 1. Third values were significantly low in group 2 compared to groups 1 and 3. Regarding the third measurement, there was no significant difference between the groups 1 and 3. Tissue injury is closely related with condition of microvascular perfusion after I/R. Rosuvastatin can protect tissue perfusion in the experimental testicular torsion model.  相似文献   
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Diabetic foot disease causes important morbidity in diabetic population, and amputation due to diabetic foot disease occurs more often than in general population. We have been evaluating patients with diabetic foot disease in a multidisciplinary approach since year 2000. In the current study, we sought to investigate the change in amputation rate and its predictors in diabetic foot with a multidisciplinary team approach. Seventy-four patients (52 male, 22 female) hospitalised between January 2002 and December 2007 were retrospectively analysed. Sixteen out of 74 have undergone amputation. We found overall amputation rate as 21.6%, which is lower than previously reported from our institution (36.7 and 39.4%, respectively). Major amputations (syme, below-knee, above-knee) were applied to 11 patients (14.9%). A logistic regression model including osteomyelitis, peripheral neuropathy, peripheral vascular disease, hypertension, gangrene and age revealed that gangrene is now the only significant predictor for amputation. Our observations confirm that amputation rate has declined after implementation of a multidisciplinary team work, and risk factors apart from presence of gangrene are no longer amputation predictors in our centre.  相似文献   
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Malaria is a mosquito-borne infectious disease caused by the genus Plasmodium. It causes one million deaths per year in African children under the age of 5 years. There is an increasing development of resistance of malarial parasites to chloroquine and other currently used anti-malarial drugs. Some plant products such as the indoloquinoline alkaloid cryptolepine have been shown to have potent activity against P. falciparum in vitro. On account of its toxicity, cryptolepine is not suitable for use as an antimalarial drug but a number of analogues of cryptolepine have been synthesised in an attempt to find compounds that have reduced cytotoxicity and these have been investigated in the present study in human sperm and lymphocytes using the Comet assay. The results suggest that cryptolepine and the analogues cause DNA damage in lymphocytes, but appear to have no effect on human sperm at the assessed doses. In the context of antimalarial drug development, the data suggest that all cryptolepine compounds and in particular 2,7-dibromocryptolepine cause DNA damage and therefore may not be suitable for pre clinical development as antimalarial agents.  相似文献   
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AIM: TO investigate the effect of exogenous erythro- poietin (EPO) administration on acute lung injury (ALI) in an experimental model of sodium taurodeoxycholate- induced acute necrotizing pancreatitis (ANP). METHODS: Forty-seven male Wistar albino rats were randomly divided into 7 groups: sham group (n = 5), 3 ANP groups (n = 7 each) and 3 EPO groups (n = 7 each). ANP was induced by retrograde infusion of 5% sodium taurodeoxycholate into the common bile duct. Rats in EPO groups received 1000 U/kg intramuscular EPO immediately after induction of ANP. Rats in ANP groups were given 1 mL normal saline instead. All animals were sacrificed at postoperative 24 h, 48 h and 72 h. Serum arnilase, IL-2, IL-6 and lung tissue malondialdehyde (MDA) were measured. Pleural effusion volume and lung/body weight (LW/BW) ratios were calculated. Tissue levels of TNF-a, IL-2 and IL-6 were screened immunohistochemically. Additionally, ox-LDL accumulation was assessed with immune-fluorescent staining. Histopathological alterations in the lungs were also scored.RESULTS: The mean pleural effusion volume, calculated LW/BW ratio, serum IL-6 and lung tissue MDA levels were significantly lower in EPO groups than in ANP groups. No statistically significant difference was observed in either serum or tissue values of IL-2 among the groups. The level of tumor necrosis factor-(~ (TNF-(~) and IL-6 and accumulation of ox-LDL were evident in the lung tissues of ANP groups when compared to EPO groups, particularly at 72 h. Histopathological evaluation confirmed the improvement in lung injury parameters a~er exogenous EPO administration, particularly at 48 h and 72 h. CONCLUSION: EPO administration leads to a significant decrease in ALI parameters by inhibiting polymorphonuclear leukocyte (PMNL) accumulation, decreasing the levels of proinflammatory cytokines in circulation, preserving microvascular endothelial cell integrity and reducing oxidative stress-associated lipid peroxidation and therefore  相似文献   
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Lipoma within an inverted Meckel's diverticulum presenting with hemorrhage and partial intestinal obstruction is an exceptional clinical entity.We report a case of 47-year-old male with a history of recurrent episodes of partial intestinal obstruction and melena due to a subserosal lipoma located in the base of an inverted Meckel's diverticulum.According to our knowledge,this is the first case of a lipoma within a Meckel's diverticulum giving rise to this clinical scenario without the existence of heterotrophic gastric or pancreatic tissues.  相似文献   
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