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Intrahepatic shunt ratio was calculated from the fraction of the uptake constant and the blood background, analyzing the data of 99mTc-(Sn)-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatobiliary imaging by Rutland method. Shunt flow and total hepatic blood flow (THBF) were also calculated from the values for the effective hepatic blood flow (EHBF) estimated from the blood clearance technique. In 15 cases of normal volunteer, the average of the shunt ratio, shunt flow, and THBF were 18.4 +/- 5.4 (S.D.)%, 137.8 +/- 49 ml/min, and 753 +/- 83.2 ml/min, respectively. In 8 cases of chronic hepatitis, the values were 35.2 +/- 2.6%, 276 +/- 55.4 ml/min, and 794.1 +/- 119.4 ml/min, respectively. In 12 cases of liver cirrhosis, the values were 51.4 +/- 12.6%, 353.9 +/- 141.3 ml/min, and 685.6 +/- 174.8 ml/min, respectively. In cases of chronic hepatitis and liver cirrhosis, in comparison with normal cases, the values for the shunt ratio and shunt flow were significantly increased (p less than 0.001) and those for EHBF were significantly decreased (p less than 0.001), but those for THBF were not significantly altered. There was a significant inverse correlation between the shunt ratio and EHBF (r = -0.842) in all 35 cases. This method is considered to be useful for differential diagnosis, estimation of the grade of the diseases, and evaluation of pathophysiology of various diffuse liver diseases.  相似文献   
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Tracking performance was investigated in normal and clumsy children in two age-groups, six to seven and 10 to 11 years. Target signals moving unpredictably along a straight line had to be tracked, both with and without visual feedback. Performance was described in three ways: (1) performance in the low-frequency range (LF); (2) the delay between target signal and tracking movement (DL); and (3) a measure of tracking quality or over-all similarity in the shape of target signal and tracking movement (Q). Clumsy children in both age-groups had a lower tracking quality (Q) and longer delay (DL) than the normal children. Disturbances in the regulation of attention seemed to affect tracking performance, particularly of the six- to seven-year-old clumsy children. There was no significant difference between normal and clumsy children in the effect of visual feedback on tracking performance. This suggests that clumsiness is not linked to disturbance of integration of visual feedback information and motor processes.  相似文献   
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In Brazil, Public Health specialization courses with the characteristics presently adopted by the National School of Public Health, i.e., short duration and great amplitude, are relatively recent, having started approximately fifteen years ago. In Brasília, nine such courses have been already completed, having, six of them, directive and/or teaching involvement by the authors. Results on a final assessment of one the courses are herewith presented in order to introduce our experience as a contribution to future analogous initiatives. The assessment was applied to a random sample of students, teachers and coordinators, with the objective of identifying positive and negative appreciations about methodological, operational, administrative and institutional aspects. Answers were quite variable, with the highest frequencies scored to field work and to the apprehension on admitting graduates to the Health System. Such aspects deserve final differentiated discussion.  相似文献   
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CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated.  相似文献   
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Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore.  相似文献   
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BACKGROUND: Insulin resistance (IR) and inflammation are associated with increased risk of cardiovascular disease in the general population. Continuous glucose absorption in peritoneal dialysis (PD) may induce hyperglycemia and hyperinsulinemia. METHODS: We evaluated IR in nondiabetic patients receiving PD, and analyzed the association between IR and systemic inflammation biomarkers by performing a cross-sectional study on ambulatory dialysis. A total of 25 nondiabetic patients receiving PD and 25 healthy individuals, matched for gender, age, and body mass index (BMI), were included. The PD group was composed of 11 men and 14 women, with a mean age of 47 +/- 14 years and mean BMI of 25.5 +/- 4.7 kg/m(2). The control group was composed of 10 men and 15 women, with a mean age of 45 +/- 12 years and BMI of 24.0 +/- 2.8 kg/m(2). RESULTS: IR was evaluated by the homeostasis model assessment method (HOMA-IR). Inflammation was assessed through high-sensitivity C-reactive protein (CRP) and fibrinogen. Body composition and truncal fat were evaluated by dual energy x-ray absorptiometry. HOMA-IR was significantly higher (P < .0001) in subjects receiving PD (4.9, range: 2.3-9.3 mmol/L x muU/mL) compared with healthy subjects (1.2, range: 0.4-4.8 mmol/L x muU/mL). As expected, compared with controls, patients receiving PD had significantly higher levels of insulin (26.5 +/- 7.5 muU/mL vs 6.3 +/- 3.4 muU/mL; P < .0001), CRP (6.3, range: 0.3-61.1 mg/L vs 2.4, range: 0.6-5.9 mg/L; P = .001), and fibrinogen (379 +/- 101 mg/dL vs 268 +/- 66 mg/dL; P < .0001). However, there were no significant differences in body and truncal fat mass between the groups. A significant correlation between HOMA-IR and fibrinogen (Rho = 0.48; P = .01) was observed. However, no correlation was found between HOMA-IR and CRP. Also, no significant correlations were found between HOMA-IR and body fat mass (Rho = 0.11), and between HOMA-IR and truncal fat mass (Rho = 0.19). CONCLUSIONS: Patients receiving PD demonstrate a state of IR that is associated with high circulating levels of fibrinogen. This suggests that hyperfibrinogenemia may be involved in the pathogenesis of IR in this setting.  相似文献   
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OBJECTIVE: The purpose of this study was to assess the accuracy of prenatal ultrasound measurement of anteroposterior renal pelvis diameter (APD) to discriminate between significant uropathy and idiopathic renal pelvis dilatation. METHODS: One-hundred-and-three neonates who were found to have fetal renal pelvis dilatation, defined as presence of an APD > or = 5 mm, underwent systematic investigation for uropathies and were prospectively followed. An ultrasound scan was performed after the first week of postnatal life and all infants underwent a voiding cystourethrogram. Neonates with an APD larger than 10 mm underwent renal scintigraphy. Ultrasound scans, clinical examination and laboratory reviews were scheduled at 6-month intervals. Receiver-operating characteristics (ROC) curves were constructed to determine the best cut-offs for APD to identify renal units with significant uropathy as well as those requiring surgical intervention. Significant uropathy was defined as the presence of well-established urinary tract abnormalities or when there was abnormal renal scintigraphy. RESULTS: The estimated area under the curve for APD was 0.900 (95% CI, 0.841-0.942) indicating excellent power to discriminate between idiopathic pelvis dilatation and significant uropathy. The sensitivity and specificity for the 7.5 mm cut-off point were 97.9% and 40.6%, respectively. To identify infants who required surgical intervention, the calculated area under the curve was 0.953 (95% CI, 0.908-0.980). CONCLUSION: Our results suggest that measurement of APD is an excellent test to identify fetuses with significant uropathy, as well as those requiring postnatal intervention.  相似文献   
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