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41.
AIM:To examine the possible role of agents elevating cAMP to release NO from aortic en-dothelial cells. METHODS:NG-nitro-L-arg inine methylester (L-NAME) , an inhibitor of NO synthase, partially inhibited endothelium-dependent relaxation evoked in phenylephrine-precontracted rings by isoproterenol and abolished relaxation mediated by forskolin 0. 2 umol L-1.RESULTS: In rings without en-dothelium, isoproterenol and forskolin were less effective relaxants and L-NAME had no effect on the responses. In methylene blue-treated rings isoproterenol- and forskolin-induced relaxation were prevented in both en-dothelium-intact and -denuded rings, but the inhibitory effects of methylene blue were significantly more in rings with endothelium than in those without. On the other hand, relaxation induced by sodium nitroprusside was not inhibited by L-NAME, but was inhibited by methylene blue in both the endothelium-intact and -denuded rings. The concentration relaxation curves to sodium nitroprusside after methylene bl  相似文献   
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Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation.  相似文献   
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A 17-year-old male with systemic lupus erythematosus presented with clinical signs of severe constrictive pericarditis that was confirmed by cardiac catheterization. At surgery, a fibrous pericardium was removed, followed by complete relief of symptoms. Immunopathology of the pericardial tissue revealed deposition of IgG, IgM, and C3. A review of the literature produced only three similar cases. Although rare, constrictive pericarditis, a potentially life threatening complication, may occur in systemic lupus erythematosus presumably with an immunological basis.  相似文献   
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Two cases of spontaneous perforation of the colon in Ehlers-Danlos syndrome type IV are reported, and eight cases previously reported in the English literature are reviewed. Emergency surgery for acute free colon perforation in patients with Ehlers-Danlos syndrome should be carried out in the following standard manner: exteriorization of the perforation or resection of the involved colon with end colostomy, and either closure of the rectal stump (Hartmann procedure) or distal mucous colostomy. The reported experience although small, indicates that a high incidence of recurrent perforation can be expected if bowel continuity is reestablished. Permanent colostomy status, therefore, appears advisable, despite the young ages of most of the patients.  相似文献   
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