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31.
The effects of thimerosal, a sulfhydryl oxidizing agent on nitrergic, endothelium-dependent and -independent relaxations were investigated to examine the possibility that the nitrergic neurotransmitter and endothelium-derived relaxing factor (EDRF) could be S-nitrosothiol or free nitric oxide (NO) in the isolated mouse corpus cavernosum. Thimerosal (5 x 10(-6)-2 x 10(-5) M) inhibited or almost abolished electrical field stimulation--(EFS, 30V, 0.5 ms, 15 sec, 1, 2, 4, 8, 16 Hz), acetylcholine--(ACh, 5 x 10(-8)-1.25 x 10(-6) M), glyceryl trinitrate--(GTN, 3 x 10(-7)-3 x 10(-6) M), and S-nitrosoglutathione--(GSNO, 5 x 10(-6)-1.25 x 10(-4) M) induced relaxations. Thiomerosal inhibition seems to be specific to L-arginine NO pathways since it had no effect on acidified sodium nitrite--(10(-4)-5 x 10(-4) M), photoactivated sodium nitrite--(2 x 10(-4) M), isoprenaline--(10(-6) M), or papaverine--(10(-4) M) elicited relaxations. Moreover, the inhibitory effect of thimerosal on the nitrergic, ACh- or GTN-induced relaxations were partly reversed by sulfhydryl-containing compounds, L-cysteine (10(-3) M), dithiothreitol (10(-3) M), or glutathione (10(-3) M). However L-methionine (10(-3) M), which contains a methyl group on the sulphur atom, failed to restore the thimerosal inhibition. Thimerosal did not change the contraction produced by 10(-4) M NG-nitro-L-arginine methyl ester. These findings indicate that the nitrergic neurotransmitter as well as EDRF may not be free NO but NO-transferring molecules, probably S-nitrosothiols, in the mouse corpus cavernosum.  相似文献   
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OBJECTIVE: The purpose of this study was to evaluate the CT findings of pulmonary artery aneurysms in patients being treated for Beh?et's disease. MATERIALS AND METHODS: Thirteen patients with Beh?et's disease who had a total of 46 aneurysms were included in the study. All patients underwent helical CT before and after treatment. Both initial and follow-up CT scans were evaluated for location, number, and size of aneurysms and for thrombosis and pulmonary parenchyma changes. RESULTS: Thirty-five (76%) of the 46 aneurysms completely disappeared during the 3-42 months of treatment (mean, 21 months), and the remaining 11 aneurysms (24%) became smaller. Both disappearance and regression of aneurysms were preceded by thrombus formation. In 15 initially thrombosed aneurysms (33%), the thrombus increased in size during treatment. After treatment, the thrombus regressed and the pulmonary artery aneurysms disappeared. Thirty-one initially nonthrombosed aneurysms (67%) first became thrombosed during treatment; later, the thrombus regressed and the aneurysm decreased in size. Perianeurysmal consolidation and air-space nodules detected in seven patients disappeared in the early stages of treatment. Mosaic attenuation areas were seen in eight patients and disappeared in seven (88%) after treatment. CONCLUSION: Pulmonary artery aneurysms in Beh?et's disease may become smaller or disappear with medical treatment. Mural thrombotic changes may be observed during the regression of pulmonary artery aneurysms. Helical CT is helpful in the diagnosis and follow-up of aneurysms and thrombosis in Beh?et's disease.  相似文献   
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Vanadium, a transitional element belonging to Vb group is wide-spread both in vegetal and animal world. Although known by more a hundred years ago only in 1985 its hypoglycaemic properties were established. Recent research shown that the hypoglycaemic properties and the toxicity are influenced both by vanadium valence state and organic moiety that is binding it.  相似文献   
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Exist a statistically significant association between a diagnosis of coronary heart disease and certain oral health parameters. These parameters are independent and more strongly associated with coronary heart disease than were recognized risk factors, such as serum cholesterol levels, body mass index, diabetes and smoking status. The correlation between serum and salivary cholesterol concentration and the role of salivary lipids in oral health have been poorly characterized. Lipids in saliva are mostly glandular in origin, through some may diffuse diffuse directly from the serum. The surface of the enamel (in case of dietary fat which have an cariostatic effect) is protected against demineralization by a mixture of salivary lipids and proteins. Salivary lipids may have anucleating role in the early mineralization of the dental plaque. The prevalence of periodontal disease may be increased in patients with atherosclerosis, and dental and periodontal infections have been shown to be associated with occurrence of acute and chronic coronary heart disease. Among the known risk factors of atherosclerosis, high serum lipid levels, especially cholesterol may be important with regard to periodontal health.  相似文献   
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The dishomeostazical theory (etiopathogenic integrative concept) allows an ample and complex vue on the stomatognathic system dysfunctional syndrome, because it begins from the perception of the stomatognathic system (SS) as a whole in which the alteration of each element can induce the disfunction of the entire system. The purpose of this study is to demonstrate that the neuroendocrine suprasystemic factor (STH hypersecretion on adult organism) disturbs every element of the SS and induces an important alteration of the fundamental cranio-mandibular relations.  相似文献   
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Objectives: To investigate the correlation of nuclear p53 accumulation with disease outcome in a cohort of patients with transitional cell carcinoma of the bladder. Methods: A total of 90 patients (11 female, 79 male) with transitional cell carcinoma of the bladder were included in this study. Tumour samples from the primary tumour were analysed by immunohistochemistry for nuclear accumulation of p53 protein. Outcome of each patient was recorded and investigated for a possible relation with p53 status. Results: Nuclear p53 deposition was determined in 22 specimens. The nuclear p53 deposition was seen in less than 20% of the nuclei examined in 13 and more than 20% in 9 cases. No stromal staining was observed. Nuclear p53 deposition was present in 15.2% (7/46) of grade 2 tumours, and 34% (15/44) of grade 3 tumours (p=0.037). Stage distribution revealed 15.5% (5/33) positivity in stage pTa, 25.8% (8/31) in pT1 and 34% (9/26) in stage pT2–3 tumours. Tumours with p53 nuclear accumulation had a higher rate of recurrence and progression and shorter survival. Conclusion: Results of the current study indicate p53 as an important factor in determination of biological behaviour of bladder cancer.  相似文献   
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