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41.
BACKGROUNDRecurrent acute pancreatitis (RAP) may be a presenting feature of and an indication for resection of pancreatic cysts, including intra-ductal papillary mucinous neoplasm (IPMN). Few data are available regarding the prevalence of malignancy and post-operative RAP in this population.AIMTo study the role of resection to help prevent RAP and analyze if presentation as RAP would be a predictor for malignancy.METHODSThis retrospective study assessed 172 patients who underwent surgical resection of pancreatic cystic neoplasms at a university hospital between 2002 and 2016. The prevalence of preoperative high-risk cyst features, and of neoplasia was compared between patients with and without RAP. To identify the cause of pancreatitis, all the patients had a detailed history of alcohol, smoking, medications obtained, and had cross-sectional imaging (contrast-enhanced computed tomography/magnetic resonance imaging) and endoscopic ultrasound to look for gallstone etiology and other structural causes for pancreatitis. The incidence of RAP post-resection was the primary outcome.RESULTSIPMN accounted for 101 cases (58.7%) {[branch duct (BD) 59 (34.3%), main duct (MD) 42] (24.4%)}. Twenty-nine (16.9%) presented with RAP (mean 2.2 episodes): 15 had BD-IPMN, 8 MD-IPMN, 5 mucinous cystic neoplasm and 1 serous cystic neoplasm. Malignancy was similar among those with vs without RAP for all patients [6/29 (20.7%) vs 24/143 (16.8%)] and IPMN patients [6/23 (26.1%) vs 23/78 (29.5%)], although tended to be higher with RAP in BD-IPMN, [5/15 (33.3%) vs 3/44 (6.8%), P = 0.04]. At mean follow-up of 7.2 years, 1 (3.4%) RAP patient had post-resection RAP. The mean episodes of acute pancreatitis before vs after surgery were 3.4 vs 0.02 (P < 0.0001). CONCLUSIONMalignancy was not increased in patients with pancreatic cystic neoplasms who have RAP compared to those without RAP. In addition, specific cyst charac-teristics were not clearly associated with RAP. The incidence of RAP was markedly decreased in almost all patients following cyst resection.  相似文献   
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A prospective study of visceral leishmaniasis in an endemic area of Brazil   总被引:13,自引:0,他引:13  
The epidemiology, clinical patterns, and risk factors for visceral leishmaniasis were prospectively studied in an endemic area of Brazil. The prevalence of disease was 3.1% for children less than 15 years of age, and the annual incidence was 4.3 cases per 1,000 children. The number of children with disease fluctuated yearly and seasonally, and distribution of the disease varied within the endemic area. Risk factors included young age (median, three years) and malnutrition before the onset of disease. Intestinal parasitism, recent migration into the area, and house location within the area did not influence the progression of infection to disease. Serological testing indicated that 7.5% of children were infected with Leishmania each year and that the ratio of disease to infection was 1:18.5 for the whole area and 1:6.5 for the section with the highest prevalence of disease. Early diagnosis and therapy altered clinical patterns of the disease.  相似文献   
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Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most widely used drugs in the United States. Ulcers are found with an endoscopy in 15%-30% of patients who are using NSAIDs regularly, and the annual incidence of upper gastrointestinal (GI) clinical events is 2.5%-4.5% among those who use NSAIDs regularly. Upper GI symptoms, such as dyspepsia, also occur in up to 60% of patients taking NSAIDs. H2-receptor antagonists when used at standard doses are not effective at preventing gastric ulcers resulting from the use of NSAIDs. Misoprostol effectively decreases NSAID-induced ulcers and GI complications, but issues of compliance (multiple daily doses) and side effects (eg, diarrhea and dyspepsia) may limit its use. Once-daily therapy with proton pump inhibitors has been documented to significantly decrease the development of NSAID-associated ulcers in endoscopic studies, reduce the rate of NSAID-related ulcer complications, and reduce upper GI symptoms in NSAID users.  相似文献   
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OBJECTIVES: The aim of this study was to assess the development of erosive esophagitis, the development of gastroesophageal reflux disease (GERD) symptoms in patients without prior symptomatic or endoscopic GERD, and the worsening of GERD symptoms in patients with prior symptomatic GERD in a post hoc analysis of eight double-blind prospective trials of Helicobacter pylori (H. pylori) therapy in 1165 patients. METHODS: Patients with active or past duodenal ulcer and without baseline erosive esophagitis had end of study endoscopies 4-30 wk after completion of therapy. A total of 533 patients had heartburn and regurgitation scores assessed at baseline and 4 wk after end of therapy, and were divided into two groups: 1) no prior GERD symptoms (N = 127) and 2) prior GERD symptoms (N = 406). H. pylori was assessed at baseline and > or = 4 wk after therapy by rapid urease test, histology, and culture. RESULTS: Erosive esophagitis developed in 24 (4%) of 621 patients with cure versus 14 (3%) of 544 with persistent H. pylori (OR = 1.52, 95% CI = 0.78-2.97). In the longest study (28-30-wk follow-up), esophagitis developed in two (7%) of 28 patients with cure versus five (7%) of 76 with persistent infection. New GERD symptoms developed in 13 (14%) of 92 patients with cure versus seven (20%) of 35 with persistent infection (OR = 0.66,95% CI = 0.24-1.82). GERD worsened in 20 (7%) of 269 with cure vs 20 (15%) of 137 with persistent H. pylori (OR = 0.47, 95% CI = 0.24-0.91; p = 0.02). CONCLUSIONS: Our results do not support the hypothesis that H. pylori eradication in patients with duodenal ulcer disease leads to the development of erosive esophagitis, the development of new symptomatic GERD, or worsening of symptoms in patients with pre-existing GERD.  相似文献   
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Microsatellite Analysis of Sporadic Flat and Depressed Lesions of the Colon   总被引:1,自引:0,他引:1  
Prior studies of molecular and genetic derangements in flat and depressed lesions of the colon have revealed lower frequencies in a number of markers commonly present in exophytic lesions. These and other differences suggest that flat lesions are driven by alternative pathways. We reviewed a database of patients who had undergone endoscopic mucosal resection (EMR) for flat and depressed lesions at the University of Chicago from January 2001 to April 2003. Formalin-fixed and paraffin-embedded colonic samples were retrieved from the tissue bank, and five standardized mononucleotide and dinucleotide microsatellite regions were analyzed for instability (MSI) using fluorescently labeled forward primers in nonmultiplex reactions. Sixteen patients were identified with flat or depressed lesions who had adequate tissue specimens available for MSI analysis. Of these specimens, eight were tubular adenomas, three were tubulovillous adenomas, and five were carcinomas in situ. Four of the lesions were microsatellite unstable, each at a single locus, and one lesion showed probable instability at a second locus. Eleven lesions were microsatellite stable. Aberrations in DNA repair mechanisms do not appear to significantly contribute to the molecular derangements underlying sporadic flat or depressed colonic lesions. The molecular bases that underlie the aggressive behavior of sporadic flat and depressed lesions remain to be determined, and further investigation is warranted.  相似文献   
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The brain serotonin (5-hydroxytryptamine; 5-HT) system is a powerful modulator of emotional processes and a target of medications used in the treatment of psychiatric disorders. To evaluate the contribution of serotonin 5-HT1A receptors to the regulation of these processes, we have used gene-targeting technology to generate 5-HT1A receptor-mutant mice. These animals lack functional 5-HT1A receptors as indicated by receptor autoradiography and by resistance to the hypothermic effects of the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). Homozygous mutants display a consistent pattern of responses indicative of elevated anxiety levels in open-field, elevated-zero maze, and novel-object assays. Moreover, they exhibit antidepressant-like responses in a tail-suspension assay. These results indicate that the targeted disruption of the 5-HT1A receptor gene leads to heritable perturbations in the serotonergic regulation of emotional state. 5-HT1A receptor-null mutant mice have potential as a model for investigating mechanisms through which serotonergic systems modulate affective state and mediate the actions of psychiatric drugs.  相似文献   
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