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141.
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The role of platelet-activating factor in mediating the cardiovascular and peripheral cellular responses to large-colon ischemia and reperfusion, was explored in anesthetized ponies. A specific platelet-activating factor (PAF) antagonist (WEB 2086) was administered to a group of 6 ponies, and another 6 ponies (controls) were given an equivalent volume of saline solution, prior to 1 hour of large-colon torsion. After correction of the torsion, ponies were monitored during the reperfusion period. Significant (P < 0.05) hypotension and metabolic acidosis developed in all ponies after correction of colonic torsion, cardiac index increased initially, but then decreased significantly (P < 0.05) over the study period. Mean times between correction of torsion and onset of cardiac failure and death were not different between groups. Significant (P < 0.05) thrombocytopenia developed during the reperfusion period in control ponies, but not in WEB-treated ponies. Blood leukocyte concentration in control ponies was more variable and significantly (P < 0.05) decreased immediately upon reperfusion, compared with that in WEB-treated ponies. We conclude that although the cardiovascular responses to colonic ischemia and reperfusion are not prevented by use of a specific PAF-antagonist, specific peripheral cellular responses are mediated by PAF. 相似文献
143.
BACKGROUND & AIMS: Whether inflammation of the cardia indicates gastroesophageal reflux disease (GERD) and/or is a manifestation of pangastritis caused by Helicobacter pylori infection is unknown. The aim of this study was to evaluate the relationship between cardia inflammation, H. pylori infection, and cardia intestinal metaplasia in patients with and without GERD. METHODS: Patients with GERD were compared with controls undergoing endoscopy for a variety of other conditions. Endoscopic biopsy specimens from the distal esophagus and cardia, fundus, and antrum were evaluated for inflammation, H. pylori infection, and intestinal metaplasia. RESULTS: Neither the prevalence of H. pylori infection (controls, 48%; GERD, 41%) nor cardia inflammation (controls, 41%; GERD, 40%) differed between groups. All 11 controls and 22 of 23 patients with GERD (96%) and cardia inflammation had H. pylori infection. Esophagitis was more common among GERD patients (33%) than controls (7%; P = 0.01). Cardia intestinal metaplasia was more common among controls (22%) than GERD patients (3%; P = 0.01); all had cardia inflammation, 7 had H. pylori infection, and 6 had metaplasia elsewhere in the stomach. CONCLUSIONS: The prevalence of cardia inflammation is similar in patients with and without GERD and is associated with H. pylori infection (P < 0.001). Cardia intestinal metaplasia is associated with H. pylori-related cardia inflammation (P = 0.01) and intestinal metaplasia elsewhere in the stomach, indicating that it is distinct from Barrett's esophagus. 相似文献
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Iranian Jews represent an ancient community with a very high degree of inbreeding. Although the community remained relatively isolated, it had strong ties with Babylonian Jewry in Iraq. Several genetic disorders have been reported to be frequent among Iranian Jews, in particular, corticosterone methyloxydase deficiency type II, polyglandular syndrome, and rimmed vacuole myopathy. Based on the data collected in our clinic, recessive and dominant deafness also appear to be frequent. Other diseases, such as beta-thalassemia, achromatopsia, colobomatous microphthalmia, Dubin-Johnson syndrome, and congenital myasthenia gravis, were frequent in both the Iranian and Iraqi Jewish communities. The place of origin of the families within Iran and the results of molecular studies suggest some reason(s) for the high frequency of these disorders among Iranian Jews. While the high frequency of some of the disorders, such as corticosterone methyloxydase deficiency type II, represents a founder effect, in other diseases (such as beta-thalassemia) it was secondary to heterozygote advantage. 相似文献
146.
VN Koshelev DV Gol'dshte?n TG Sionskaia GM Shub 《Canadian Metallurgical Quarterly》1993,150(5-6):10-12
A considerable frequency of infected bed of the gallbladder in different forms of cholecystitis was established, the anaerobic microflora being inoculated more often. A direct dependence of the frequency of infecting the bile and gallbladder bed on the patient's age and duration of having chronic cholecystitis was shown. The sterilization and prevention of reinfection of the gallbladder bed after the removal of it can be achieved by the laser irradiation of the total bed surface inspite of the absence of clear symptoms of acute inflammation of the bladder and the surrounding tissues, and the cleansing should be performed after the manipulations on extrahepatic bile ducts are completed. 相似文献
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Beta-lactamases have been reported to be largely responsible for beta-lactam resistance in Mycobacteria. We report the characterization of a cell-associated beta-lactamase from Mycobacterium smegmatis. The enzyme hydrolyzed the "beta-lactamase-stable" oximinocephalosporins. Nitrocefin was the best substrate. 6-Beta-iodopenicillanate, clavulanate and sulbactam were effective inhibitors, whereas the Ki value for aztreonam was high. From its substrate and inhibitor profile, the enzyme appeared to be a cephalosporinase of group 2e. 相似文献
150.
HY Song CH Régnier CJ Kirschning DV Goeddel M Rothe 《Canadian Metallurgical Quarterly》1997,94(18):9792-9796