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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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Studies on the development of imaging agents for targeting neuroreceptors is an area of considerable interest owing to the limited availability of specific as well as selective radiolabeled agents. Therefore, with an aim of developing a receptor-specific agent, iminodiacetic acid (IDA) derivative of 5-hydroxy tryptamine viz., HTIDA has been synthesized. HTIDA could be radiolabeled with the synthon [(99m)Tc(CO)(3)(H(2)O)(3)](+) in >98% yield. The biodistribution studies in normal Swiss mice showed that the (99m)Tc(CO)(3)-HTIDA crosses the blood-brain barrier successfully with a brain uptake of 0.5%ID/g at 5min post injection. The other relevant observations from biodistribution studies included no significant uptake in any other organ and fast clearance from blood, lungs and liver.  相似文献   
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Ziprasidone (Geodone), a novel atypical antipsychotic agent, is recently approved for the treatment of schizophrenia. It undergoes extensive metabolism in preclinical species and humans after oral administration, and only a very small amount of administered dose is excreted as unchanged drug. In vitro studies using human liver microsomes have shown that the oxidative metabolism of ziprasidone is mediated primarily by CYP3A4. However, coadministration of ziprasidone with ketoconazole, a CYP3A4 inhibitor, showed only a modest increase in its exposure. Therefore, in vitro metabolism of ziprasidone was investigated in hepatic cytosolic fractions to further understand its clearance mechanisms in preclinical species and humans. The major metabolite from incubation of ziprasidone in cytosolic fractions of rat, dog, and human was characterized by liquid chromatography-tandem mass spectrometry and found to be the product of reductive cleavage. Derivatization and hydrogen/deuterium exchange were used to deduce that the addition of two hydrogen atoms had occurred at the benzisothiazole moiety. Further studies to determine the enzyme involved in the formation of this metabolite are currently in progress. The identification of this novel metabolite in cytosol has clarified the clearance mechanism of ziprasidone in humans and preclinical species.  相似文献   
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BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type.  相似文献   
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