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Hydatid disease has characteristic imaging features on CT, which allow accurate preoperative diagnosis in most cases. However, when it occurs at unusual locations the diagnosis is often difficult, especially as the imaging appearance varies at different sites. In this article we have presented a pictorial review of the CT features of disease due to Echinococcus granulosus at various sites in the human body.  相似文献   
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Nitric oxide 9 years on.   总被引:2,自引:0,他引:2       下载免费PDF全文
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We report respiratory obstruction following surgery in the sitting position with tracheal intubation and placement of a transesophageal echocardiography probe. Obstruction was due to pharyngeal oedema, which resolved with 24 hours. The mechanisms of this complication are discussed.  相似文献   
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The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect.  相似文献   
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BACKGROUND & AIMS: Heat shock proteins (Hsps), induced by cell stress, are known to protect against cellular injury. Recent studies have indicated that Hsp60 expression, induced by exposure to water immersion stress, protects against pancreatitis induced by administration of supramaximal doses of cerulein in rats. However, the mechanisms responsible for this protection are not known. Methods: Rats were water-immersed for 3-12 hours. Pancreatitis was induced by cerulein administration. RESULTS: The results confirm that prior induction of Hsp60 expression by water-immersion stress significantly ameliorates the severity of cerulein-induced pancreatitis as judged by the markedly reduced degree of hyperamylasemia, pancreatic edema, and acinar cell necrosis. Water immersion also prevents the subcellular redistribution of cathepsin B from a lysosome-enriched fraction to a heavier, zymogen granule-enriched fraction that is known to occur in this model of pancreatitis. Intra-acinar cell activation of trypsinogen that occurs shortly after exposure to a supramaximally stimulating dose of cerulein both in vivo and in vitro is prevented by prior water-immersion stress and Hsp60 expression. The protection against pancreatitis that follows water-immersion stress is not caused by alterations of cholecystokinin receptors, because water immersion does not alter the typical biphasic amylase secretory response to stimulation with cerulein. CONCLUSIONS: Water-immersion stress induces Hsp60 expression, ameliorates cerulein-induced pancreatitis, and prevents intra-acinar cell activation of trypsinogen. We suggest that Hsp60 protects against cerulein-induced pancreatitis by preventing trypsinogen activation within acinar cells.  相似文献   
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