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61.
In industrialized populations, Hodgkin's disease (HD) has an initial peak in young adulthood, whereas in economically developing populations the initial peak occurs in childhood. This pattern resembles that of infection with poliovirus and suggests an infectious cofactor in the etiology. Serologic studies have linked Epstein-Barr virus (EBV) to young adult and adult HD, and viral nucleic acids and antigens have been detected in a subset of Hodgkin's tumor specimens. To investigate the association of childhood HD with EBV we studied tumor specimens from 11 children treated in Honduras and 25 children treated in the United States using in situ hybridization and antigen detection techniques. Among the patients from Honduras, tumor specimens from all cases were EBV positive. Among the patients from the United States, tumor specimens from six of seven patients with mixed cellularity histology, 2 of 15 with nodular sclerosis histology, and neither of two patients with lymphocyte-predominant histologies were EBV positive. These findings support the hypothesis that EBV contributes to the pathogenesis of HD in children, particularly in mixed cellularity HD, and raises the possibility that there are important geographic, racial, or ethnic factors in the EBV association with HD.  相似文献   
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BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7)  相似文献   
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A 16-year-old boy with Prader-Labhart-Wi11i syndrome (PLWS) had hypotonia, feeding difficulties, failure to thrive, strabismus and bilateral inguinal hernias with cryptorchidism during infancy followed by hyperphagia, marked early-onset obesity with insulin-dependent diabetes mellitus and necrobiosis lipoidica diabeticorum, short stature, hypogonadotropic hypogonadism and some of the facial characteristics of the individuals with the PLWS. IQ is estimated around 90. Cytogenetic studies showed mosaicism: 45,X, t(Y;15) with partial deletion 15 (15pter → 15ql2); 46,X, t(Y;15), dic(15)(15pter → 15ql2::15ql2 → 15pter) and 47,X,t(Y;15), dic(15), dic(15). The dic(15) was bisatel1ited, NOR-positive on both arms and represented inv dup(15). Thus, the 2 lines with the dic(15) showed partial trisomy 15 (15pter → 15q 12) and partial pentasomy 15 (15pter → 15ql2), respectively. The cell line ratios were different in lymphocyte and fibroblast cultures. The unique cytogenetic findings in this patient, the reports of a variety of chromosome 15 aberrations in PLWS; as well as aberrations of other chromosomes, suggest that the condition is a contiguous gene syndrome rather than an aneuploidy syndrome.  相似文献   
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Randomized trial of umbilical arterial catheter position: clinical outcome   总被引:2,自引:0,他引:2  
In order to determine if umbilical arterial Catheter position affects the incidence of necrotizing enterocolitis, clinical outcome was analysed in 308 infants whose umbilical arterial catheter had been randomly allocated to a high ( n =162) or a low ( n =146) position. Necrotizing enterocolitis was classified as suspected or confirmed; all renal, lower limb and local catheter complications were also recorded. High umbilical arterial catheters were in place for longer than low catheters, provided more samples and were removed as an emergency less often. Lower limb blanching and cyanosis were more common with low catheters. Eleven cases of confirmed necrotizing enterocolitis occurred in the "high" group and nine in the "low" group. One case of fatal aortic thrombosis was encountered in the high group. Positioning umbilical arterial catheters in a high position allowed longer functional use and did not increase the incidence of necrotizing cnterocolitis.  相似文献   
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68.
In East Greenland polar bears (Ursus maritimus), anthropogenic organohalogen compounds (OHCs) (e.g., polychlorinated biphenyls, dichlorodiphenyltrichloroethane, and polybrominated diphenyl ethers) contributed to renal lesions and are believed to reduce bone mineral density. Because OHCs are also hepatotoxic, we investigated liver histology of 32 subadult, 24 adult female, and 23 adult male East Greenland polar bears sampled during 1999-2002. Light microscopic changes consisted of nuclear displacement from the normal central cytoplasmic location in parenchymal cells, mononuclear cell infiltrations (mainly portally and as lipid granulomas), mild bile duct proliferation accompanied by fibrosis, and fat accumulation in hepatocytes and pluripotent Ito cells. Lipid accumulation in Ito cells and bile duct hyperplasia accompanied by portal fibrosis were correlated to age, whereas no changes were associated with either sex or season (summer vs. winter). For adult females, hepatocytic intracellular fat increased significantly with concentrations of the sum of hexachlorocyclohexanes, as was the case for lipid granulomas and hexachlorobenzene in adult males. Based on these relationships and the nature of the chronic inflammation, we suggest that these findings were caused by aging and long-term exposure to OHCs. Therefore, these changes may be used as biomarkers for OHC exposure in wildlife and humans. To our knowledge, this is the first time liver histology has been evaluated in relation to OHC concentrations in a mammalian wildlife species, and the information is important to future polar bear conservation strategies and health assessments of humans relying on OHC-contaminated food resources.  相似文献   
69.
Background: Laparoscopic Roux-en-Y gastric bypass (RYGBP) is being performed widely as a treatment of choice for morbid obesity. We present our method and experience with the first 150 consecutive cases of laparoscopic RYGBP with a 2-m long biliopancreatic limb (BP-limb). Methods: Between November 2001 and November 2003, a prospective analysis of 150 patients was performed identifying technical success and complications. Before surgery, patients underwent a strict multidisciplinary behavioral program. At operation the stomach was transected proximally with a linear stapler (60-mm, Endo-GIA) to create a prolongation of the esophagus (gastric tube) along the lesser curvature, resulting in a 40-50 ml pouch. Two meters of the proximal jejunum were bypassed (BP-limb), creating an antecolic Roux-en-Y gastro-jejunostomy to the posterior wall of the gastric tube using a 45-mm linear Endo-GIA stapler. The entero-anastomosis was created 50 cm below the gastro-jejunostomy, also with a 45-mm linear Endo-GIA. Results: Mean BMI was 50.0, and 78% of patients were females. With 100% follow-up, we found an EWL of 50% 6 months after surgery, gradually rising to 80% after 18 months. The mean operating time was 116 min for the first 50 cases and decreased to 82 min for the last 50 cases. Intestinal leakage occurred in 5 patients (3%) and bleeding in 5 (3%). Most of these complications occurred in the first 50 cases, and all but one were treated successfully with an early laparoscopic re-operation. Marginal ulcers were found in 16.6% of patients. No internal hernias have occurred. Conclusion: The operation demands advanced laparoscopic skills, but technically it is relatively simple and has an acceptable complication rate. Short-term results regarding excess weight loss are at least comparable to the RYGBP with a long alimentary limb.  相似文献   
70.
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