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The effects of histaminergic ligands on both ACh spontaneous release from the hippocampus and the expression of c-fos in the medial septum-diagonal band (MSA-DB) of freely moving rats were investigated. Because the majority of cholinergic innervation to the hippocampus is provided by MSA-DB neurons, we used the dual-probe microdialysis technique to apply drugs to the MSA-DB and record the induced effects in the projection area. Perfusion of MSA-DB with high-KCl medium strongly stimulated hippocampal ACh release which, conversely, was significantly reduced by intra-MSA-DB administration of tetrodotoxin. Histamine or the H2 receptor agonist dimaprit, applied directly to the hippocampus, failed to alter ACh release. Conversely, perfusion of MSA-DB with these two compounds increased ACh release from the hippocampus. Also, thioperamide and ciproxifan, two H3 receptor antagonists, administered into MSA-DB, increased the release of hippocampal ACh, whereas R-alpha-methylhistamine, an H3 receptor agonist, produced the opposite effect. The blockade of MSA-DB H2 receptors, caused by local perfusion with the H2 receptor antagonist cimetidine, moderated the spontaneous release of hippocampal ACh and antagonized the facilitation produced by H3 receptor antagonists. Triprolidine, an H1 receptor antagonist, was without effect. Moreover, cells expressing c-fos immunoreactivity were significantly more numerous in ciproxifan- or thioperamide-treated rats than in controls, although no colocalization of anti-c-fos and anti-ChAT immunoreactivity was observed. These results indicate a role for endogenous histamine in modulating the cholinergic tone in the hippocampus.  相似文献   
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BACKGROUND AND PURPOSE: Twenty years after the first report of laparoscopic appendectomy (LA), its role in the treatment of appendicitis is still under debate. We report herein a retrospective analysis of our cases of LA in the last 5 years, during which we adopted a policy of an almost uniform laparoscopic approach on a rather selected population composed mainly of women with acute or recurrent lower quadrant abdominal pain. PATIENTS AND METHODS: Laparoscopic appendectomy was performed on 33 male and 98 female patients. The mean age at operation was 25.7+/-11.4 years (range 11-59 years). Acute appendicitis with localized or diffuse peritonitis was present in 34 cases. In the remaining 97 patients, the operation was performed for acute or recurring symptoms of lower quadrant abdominal pain. RESULTS: There were no conversions to open surgery. The operating time was 45+/-17 minutes (range 30-110 minutes). The pathology examination of the removed appendices showed acute appendicitis in 34 cases and chronic inflammation in the remaining 97 patients. In one case, histology revealed a coexisting mucinous carcinoid that extended to the perivisceral fat, and a completion right hemicolectomy was performed. Complications were minor in most cases. Reoperation for deep abdominal abscess or hematoma was required in three cases. The mean hospital stay was 2.59+/-1.58 days (range 24 hours-11 days). CONCLUSION: In our hands, LA has proven to be safe and effective. The laparoscopic operation has significant advantages in terms of lower invasiveness and better diagnostic capability. It is especially useful in women of child-bearing age, in whom it may be considered the procedure of choice.  相似文献   
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Cortical perfusion with GABA agonists and antagonists modulates the spontaneous release of cortical acetylcholine and GABA in freely moving rats. Twenty-four hours after implantation of a dialysis fibre, cerebral cortex spontaneously released acetylcholine (3.8 +/- 0.2 pmol/10 min) and GABA (6.6 +/- 0.4 pmol/10 min) at a stable rate. Local administration of GABA (1 or 5 mM) or the GABAA agonist muscimol (25 or 50 microM) had no effect on the spontaneous release of acetylcholine. However, bicuculline (1-25 microM), a GABAA antagonist, added to the dialysis perfusate, elicited a concentration-dependent increase of acetylcholine release to approximately double that of control. This effect of bicuculline (25 microM) was completely prevented by coperfusion with muscimol (50 microM). Local administration of the GABAB receptor agonist baclofen (10 or 50 microM) elicited a concentration-dependent increase in spontaneous acetylcholine release with a maximal increase of about 60%. Intracortical administration of baclofen also decreased the spontaneous release of GABA. The GABAB receptor antagonist CGP 35348 (1 mM), administered alone for 20 min through the dialysis fibre, was without effect on spontaneous acetylcholine release; however, it completely blocked both the baclofen-induced increase in acetylcholine release and the decrease in GABA release. These results suggest that cortically released GABA exerts a tonic influence on cholinergic activity.  相似文献   
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OBJECTIVE: To critically review the literature on vardenafil in the treatment of erectile dysfunction while integrating the clinical findings with the personal experience of the authors. METHODS: Analysis of published full-length papers that were identified through Medline search from January 2000 through May 2004. Abstracts published in peer-reviewed journals from the same period were also considered. RESULTS: Efficacy, tolerability and safety, as reported in the peer-reviewed literature compares well with the authors' personal experience. Authors' personal observations include discussions on potency, selectivity, selection of initial dose, counselling for patients characteristically considered difficult-to-treat (diabetes, prostatectomy, depression), including the determination of the maximal efficacious dose and the possible role of daily dosing, optimisation of the use of vardenafil according to its pharmacokinetic and pharmacodynamic profiles (onset and reliability), and management of ED patients with or at risk for cardiovascular disease. CONCLUSIONS: Extensive experience with vardenafil as reported in peer reviewed literature confirms the important role of vardenafil in the management of patients with ED. The development of each physician's own experience with vardenafil is key to optimise overall satisfaction of this therapy by the patient and his partner.  相似文献   
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Epithelioid hemangioendothelioma (EHE) is an extremely rare vascular tumor of intermediate malignancy. Generally it develops from the peripheral veins (usually the femoral vein). We report on a case of EHE of the radial artery, developed in a 26-year-old male patient, which presented as a solitary painless mass. He had a complete resection of the tumor and of the segment of radial artery involved. The histologic examination revealed an intravascular EHE, with low mitotic index and with insufficient histologic anormalities.  相似文献   
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Beh?et disease is a heterogeneous, multisystem inflammatory disorder; vascular involvement has been considered to result from systemic vasculitis, which most frequently affects veins and occurs in 5% to 10% of these patients. However, superior vena cava (SVC) involvement is rare; it accounts for only 6% of the cases. The aim of this article is to a report on a case of SVC recanalization through the use of fibrinolysis and self-expanding stents as treatment of life-threatening SVC syndrome in a young male patient with Beh?et disease.  相似文献   
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