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51.
This study was done to identify the specific etiological agents that cause acute poliomyelitis (APM). All the children newly diagnosed clinically as APM at the Institute of Child Health, Madras, during the period May 1988 to May 1989 were recruited. Stool specimen collection, transportation and identification of viruses by culture were done by standard procedures. The total number of children recruited was 312. Specimens were contaminated/insufficient in 10. Analysis was done for 302 cases. Polio virus type II was identified in 25.5% children, type I in 18.5%, type III in 15.9%, multiple polioviruses in 6.3% and non-polio enteroviruses (NPEV) in 20.2% cases. No virus was identified in 13.6%. Among the APM cases clinically diagnosed, the proportion of NPEV has increased considerably from 5% in 1984 to 20.2% in 1988–89. The age distribution was not significantly different between polio viruses and NPEV. The distribution of polio viruses and NPEV did not differ significantly in relation to immunization status, source of water supply, method of excreta disposal and the clinical types. For surveillance and control/eradication program of poliomyelitis, laboratory confirmation is essential.  相似文献   
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Daily variability in volume of elective pediatric procedures that require anesthesia may lead to an imbalance between available operating room resources and case load. Longer intervals between scheduling and the surgical date generally result in higher operating room utilization. In this study, we sought to determine which factors influence when parents schedule their children for procedures. We also aimed to identify parents' ideal and longest acceptable waiting intervals and determine whether type of procedure, for example, affects scheduling. From a convenience sample of 250 randomly selected parents of children presenting for elective surgery, 236 completed surveys were analyzed. The remaining 14 surveys were not returned. Overall, parents scheduled their child's procedure a median of 4.3 wk (interquartile range 2.0-8.6) in advance and reported an ideal waiting interval of 3 wk (interquartile range 2-4), and longest acceptable interval of 6 wk (interquartile range 4-10). Parents were willing to wait longer to schedule cardiac (4 wk, P = 0.004) and plastic (3.5 wk, P = 0.024) surgery when compared with general surgical procedures. Overall, parents ranked severity of the child's illness, earliest available time, and surgeon's suggested date as the three most important factors influencing when their child's surgery is scheduled. The timetable for scheduling procedures was highly correlated with both mother and father having available time off work (tau(b) = 0.72, P < 0.0001). Surprisingly, parents did not show a preference for scheduling cases during vacation or summer months.  相似文献   
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Spontaneous bacterial peritonitis is a major cause of mortality after liver cirrhosis. Altered permeability of the mucosa and deficiencies in host immune defenses through bacterial translocation from the intestine due to intestinal bacterial overgrowth have been implicated in the development of this complication. Molecular mechanisms underlying the process are not well known. In order to understand mechanisms involved in translocation of bacteria, this study explored the role of oxidative stress in mediating changes in intestinal mucosal glycosylation and luminal bacterial content during cirrhosis. CCl4-induced cirrhosis in rats led to prolonged oxidative stress in the intestine, accompanied by increased sugar content of both intestinal brush border and surfactant layers. This was accompanied by changes in bacterial flora in the gut, which showed increased hydrophobicity and adherence to the mucosa. Inhibition of xanthine oxidase using sodium tungstate or antioxidant supplementation using vitamin E reversed the oxidative stress, changes in brush border membrane sugar content, and bacterial adherence. In conclusion, oxidative stress in the intestine during cirrhosis alters mucosal glycosylation, accompanied by an increased hydrophobicity of luminal bacteria, enabling increased bacterial adherence onto epithelial cells. This might facilitate translocation across the mucosa, resulting in complications such as spontaneous bacterial peritonitis.  相似文献   
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Mild heat treatment can modulate metabolism and prevent stress-induced alterations in cells and tissues. Retinoids are known to influence cellular metabolism and are essential for growth and differentiation, particularlepithelial tissue. This study examines the effect of mild heat treatment on retinoid alterations in enterocytes in the rat small intestine. Heat treatment changed the differentiation pattern of enterocytes along the villus-crypt axis, accompanied by increases in retinol, retinaldehyde, and retinoic acid in proliferating crypt cells. Activities of retinoid metabolizing enzymes such as retinaldehyde oxidase and retinaldehyde reductase were also increased. These results suggest that mild heat treatment can alter retinoid metabolism in the small intestine, which might influence epithelial cell proliferation and differentiation. The Wellcome Trust Research Laboratory is supported by the Wellcome Trust, London. The financial assistance from the Council of Scientific and Industrial Research, Government of India, is gratefully acknowledged. R.P. and S.T. are senior research fellows of the Council of Scientific and Industrial Research, Government of India.  相似文献   
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Thromboelastographic evaluation of the influence of fibrinolysis on blood loss and blood product transfusions in children during cardiac surgery. Prospective study. University-affiliated, pediatric medical center. Two hundred seventy-eight consecutive children undergoing cardiac surgery. Blood sampling for coagulation tests, including native and protamine-modified thromboelastography. Blood coagulation tests were measured before, during, and after cardiopulmonary bypass (CPB). Demographic data, perioperative blood loss, and blood product transfusions were prospectively recorded. Fibrinolysis was defined as thromboelastography of A30/MA less than 0.85 (MA, maximum amplitude; A30, amplitude 30 minutes after MA) and was noted in 3% of children pre-CPB, 16% during CPB, and 3% post-CPB. Fibrinolysis before CPB was associated with poor cardiac output. Fibrinolysis during CPB occurred in young children (aged 350 ± 836 days) undergoing complex surgery with prolonged CPB (119 ± 48.8 minutes) and deep hypothermia (25.6°C ± 4.7°C). These patients received blood products after CPB and were not fibrinolytic after transfusion. They incurred similar blood loss (in mL/kg) and received similar volumes of blood products (mL/kg) as age-matched and surgery-matched patients without fibrinolysis. A group of children at risk for fibrinolysis during CPB was identified. However, fibrinolysis during CPB did not influence blood loss or the total volume of blood products transfused.  相似文献   
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Pregnancy neither protects women from susceptibility to illness nor generally decreases drug dosage requirements of preexisting pharmacotherapy. Thus, a major concern of drug use during pregnancy is maintenance of maternal health while minimizing fetal drug exposure. Important assumptions in reproductive medicine are that fetal exposure to any medication can present risks in pregnancy--because not all risks are known, as little exposure as possible is desirable.  相似文献   
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