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991.
DNA from malignant cells is present in the serum/plasma of cancer patients and DNA from this source is amenable to analysis by polymerase chain reaction (PCR). In the present study, we evaluated whether Epstein-Barr virus (EBV) DNA is present in the serum of patients with EBV-associated Hodgkin's disease (HD). Using conventional PCR, EBV DNA was detected in serum from 30/33 patients with EBV-associated HD but in only 6/26 patients with non-EBV-associated disease (p < 0.001). Samples from healthy individuals were negative and only 5/12 infectious mononucleosis samples were positive. Real-time quantitative PCR was subsequently employed to determine the concentration of EBV DNA present in serum; among positive samples the level ranged from 1 to 705 copies per 125 microliter of serum. Post-treatment samples from 5/14 cases with EBV-associated HD contained detectable EBV DNA; analysis of this small group of cases suggests that positivity in post-treatment samples correlates with risk factors indicative of a poor prognosis. Overall, our results are consistent with the notion that DNA from Reed-Sternberg cells is present in the serum of HD patients, and further suggest that serum EBV should be evaluated as a prognostic marker. Int. J. Cancer (Pred. Oncol.) 84:442-448, 1999.  相似文献   
992.
The aim of this study was to evaluate the visual attention of children with migraine and compare it with a control group. Thirty migrainous children and 30 controls without headache were subjected to a visual attention assessment with Trail Making Tests (TMT) A/B, Letter Cancellation Test, and the Brazilian computerized test Visual Attention Test, third edition. The migraine group was evaluated after 2 days without headache. The migraine group had an inferior performance compared with the control group on TMT A ( P  = 0.03) and B ( P  = 0.001), and more errors on tasks 1 ( P  = 0.032) and 2 ( P  = 0.015) of the Visual Attention Test, presenting difficulty with selective and alternate attention. Attention is a neurological function that depends on structures such as the brainstem, cerebral cortex and the limbic system and on neurotransmitters such as dopamine and noradrenaline. The neurochemical aspects involved in the physiopathology of migraine and attention mechanisms probably predispose these children to visual attention deficits.  相似文献   
993.
Aim: We sought to study the survival of newborn children according to HIV status of the mother, that of the child and the timing of infection. Methods: This is a prospective cohort study of 883 mothers (665 HIV‐positive and 218 HIV‐negative) and their infants. Data were collected using semi‐structured questionnaires during home visits between the antenatal period and 36 weeks post‐delivery. Infant HIV status was determined at 3, 24 and 36 weeks by HIV DNA PCR. Results: The majority (81.3%) of infected infants who died were infected by 3 weeks of age. Of the HIV‐exposed infants who died, 19 (28.4%) died before 6 weeks and 38 (56.7%) died by 12 weeks. The hazard ratio (HR) of mortality at 36 weeks of age in HIV‐infected infants compared with exposed but negative infants was 8.9 (95% CI: 6.7–11.8). There was no significant difference in 36 week survival rates between HIV‐non‐exposed and HIV‐exposed but negative infants (HR: 0.7; 95% CI: 0.3–1.5). The infant being HIV‐positive at age 3 weeks (HR: 32 95% CI: 14.0–73.1) and rural site (HR: 4.4 95% CI: 1.2–23.4) were the two independent risk factors for infant death amongst HIV‐exposed infants. Conclusion: The prognosis for infants with early HIV infection was very poor in this cohort. A greater focus on prevention of early infection, earlier screening for HIV infection and access to antiretrovirals for eligible infants is recommended.  相似文献   
994.
We examined the impact of acute myocardial ischemia followed by reperfusion (AMI-R) on local and circulating renin–angiotensin system (RAS) in a swine model. The mid left anterior descending artery (n = 6) was occluded for 1 h, followed by reperfusion for 2 h. Monastryl blue/triphenyl tetrazolium chloride staining identified the area-at-risk (AAR) and infarction. A second group of control animals underwent sham operations (C: n = 4). Myocardial expression of angiotensinogen (AGT), renin, chymase, angiotensin converting enzyme (ACE), angiotensin II (Ang II), Ang II type1 receptor (AT1R) and Ang II type 2 receptor (AT2R) in the AAR and the non-ischemic left ventricle (NLV) was assessed. Serum level of these proteins at baseline and at the end of reperfusion was also examined. Chymase (P < 0.05), ACE (P < 0.05), Ang II (P < 0.05), AT1R (P < 0.05) and AT2R (P < 0.05) expressions were found to be significantly higher in the AAR compared to the NLV and C whereas no significant differences were found for AGT (P = 0.58) and renin (P = 0.38). Serum concentration of ACE was significantly higher at the end of reperfusion than at baseline (P < 0.01), whereas no significant difference was found for chymase (P = 0.71), AGT (P = 0.57) and Ang II (P = 0.19). Immunohistochemistry of myocardial sections demonstrated significantly higher expression of ACE (P = 0.02), AT1R (P = 0.01), AT2R (P = 0.02) and Ang II (P < 0.01) in the AAR as compared to the NLV, whereas no significant difference was found for renin (P = 0.39). In conclusion, AMI-R resulted in significantly higher expression of specific cardiac RAS components in AAR compared to the NLV in the acute period.  相似文献   
995.
Background: Cerebral regional oxygen saturation (rSO2) measured with near‐infrared spectroscopy (NIRS) has a well‐proven clinical utility. A goal‐oriented treatment based on the rSO2 resulted in a significant reduction in major morbidity and in a shortening of postoperative hospital stay in patients undergoing coronary revascularization. In this study, we have compared the values of superior vena cava saturation (ScvO2) continuously measured with a Pediasat catheter and the corresponding NIRS rSO2 values obtained during cardiac operations in pediatric patients. Methods: This was a prospective observational study enrolling fifteen pediatric patients (age: 6 days–7 years) undergoing cardiac operations. ScvO2 data obtained with the Pediasat during the operation were compared with simultaneously recorded NIRS rSO2 values. Results: One hundred and seventeen matched sets of data were obtained during the operation. ScvO2 continuously measured with the Pediasat was significantly correlated with the corresponding NIRS rSO2 values. However, there was a constant positive bias (ScvO2 values were higher than NIRS rSO2 values) of 5.6%, with a precision of 10.4%. Time‐related percentage changes of NIRS rSO2 were significantly correlated with the corresponding ScvO2 percentage changes. A decrease in ScvO2 is predictive for a decrease in rSO2 with a sensitivity of 73.7% and a specificity of 85.7%. Conclusions: The continuous measurement of ScvO2 values obtained by the Pediasat may provide useful information about the metabolic conditions of the brain during cardiac operations in pediatric patients if considered as percentage changes. Absolute values of ScvO2 tend to overestimate the correspondent rSO2 values.  相似文献   
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An increased risk of developing precocious puberty has been reported in children with myelomeningocele. In order to evaluate this further and to study factors associated with early or precocious puberty the medical records of all girls with myelomeningocele, born from 1970 onwards (n = 64), who were admitted to our unit were reviewed. Early/precocious puberty (E/PP) was defined as breast development or pubic hair corresponding to Tanner stage 2 before the age of 9.2 years. In 32 out of 62 cases data were sufficient for evaluation of the timing of puberty. Twenty girls had E/PP and 12 girls normal timing of puberty. In the girls who had reached the age of 9.2 years the incidence of E/PP was at least 52%. Girls with E/PP had a higher incidence of hydrocephalus, were treated with intraventricular shunts more often, and had significantly higher frequency of increased intracranial pressure during the perinatal period (p < 0.05, p < 0.01, and p < 0.001, respectively). The group of girls developing E/PP was also more severely disabled with respect to motor and urological function and had more shunt revisions. In conclusion, E/PP in girls with myelomeningocele is strongly associated with increased intracranial pressure particularly during the perinatal period.  相似文献   
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