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Intussusception is a very rare cause of intestinal obstruction in neonates. It is of extremely rare occurrence among premature neonates. We present a case of 11-day-old premature neonate who presented with abdominal distension, intolerance to feeds, vomiting, significant bilious aspirate and bleeding per rectum. The initial diagnosis of necrotizing enterocolitis (NEC) led to a delay in the diagnosis. On exploratory laparotomy, it turned out to be a case of ileo-colic intussusception with Meckel''s diverticulum as a lead point. This site of intussusception (ileo-colic) and presence of a lead point among premature neonate is of exceedingly rare occurrence and very few such cases have been reported.In this article, the published work about clinical features and management on intussusceptions in premature neonates has been reviewed. The authors intend to highlight the difficulty in distinguishing the NEC and intussusception. Subtle clinical and radiological features which can help in differentiating the two conditions have been emphasized. This can avoid the delay in diagnosis and management which can prove critical. High index of suspicion with timely intervention is the key for optimizing outcome. A diagnosis of intussusception should always be considered in any preterm infant with suspected NEC.  相似文献   
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We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca2+ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca2+ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion.  相似文献   
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Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents at the same time as the initial laparoscopy. Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome measure was complications rates. Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was 3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction, and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified: one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications. Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct.  相似文献   
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Vyas A  Pillai AG  Chattarji S 《Neuroscience》2004,128(4):667-673
The hippocampus and amygdala are important components of the neural circuitry mediating stress responses. While structural plasticity in the hippocampus may mediate cognitive aspects of behavioral impairments caused by severe stress, changes in the amygdala are more likely to contribute to the affective aspects of stress disorders. Recent reports have identified cellular and molecular correlates of stress-induced amygdaloid plasticity that may underlie anxiety. Hence, we examined the impact of chronic stress, in terms of its duration, at the cellular and behavioral levels in rats. We found that, even after 21 days of stress-free recovery, animals exposed to chronic immobilization stress (CIS) continue to exhibit enhanced anxiety, as manifested by a significant reduction in open-arm exploration and risk-assessment behavior in the elevated plus-maze. At the cellular level, we tested if CIS-induced dendritic remodeling in the amygdala is also as long-lasting as enhanced anxiety after 21 days of recovery. Indeed, long-lasting facilitation of CIS-induced anxiety is accompanied by a persistent increase in dendritic arborization of basolateral amygdala (BLA) spiny neurons. Moreover, CIS-induced BLA hypertrophy is distinct from hippocampal CA3 atrophy, which is reversible within the same period of stress-free recovery. These findings on persistent dendritic remodeling in the amygdala, in addition to highlighting important differences with hippocampal structural plasticity, may provide a cellular basis for examining anxiety and mood disorders triggered by chronic stress.  相似文献   
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  1. Cimetidine produced dose-dependent contractions in isolated guinea pig ileum and these responses were not blocked by mepyramine the H1-receptor antogonist.
  2. Atropine competitively inhibited the cimetidine-induced contractions in the guinea pig ileum.
  3. Cimetidine-induced reponses were potentiated in the presence of eserine.
Magnesium ions non-competitively inhibited the contractions due to cimetidine. Our findings suggest that cimetidine excites the guinea pig ileum through muscarinic receptors by releasing acetylcholine.  相似文献   
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