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The clinical outcome and appropriate management for patients showing 'borderline changes' on allograft biopsy after renal transplantation is still controversial. In an attempt to identify predictive factors of clinical outcome of patients with such lesions, we reviewed the clinical course of 91 patients with borderline changes. Multivariate analysis revealed significant and independent effects of histological stage (i + t < or = or > 2) and time to borderline changes (< or = or > 3 months after transplant) on serum creatinine levels at 1 year from borderline changes episodes (respectively, p = 0.04 and p = 0.02) and only a significant effect of time to borderline changes on serum creatinine levels at 2 years (p = 0.005). Renal function at 1 year and 2 years as 5- and 8-year graft survival were not significantly different in the group of patients treated with antirejection therapy (T group, n = 49) compared with the untreated group (UT group, n = 42). This study strongly suggests that borderline changes with histological score (i + t) > 2 and late episodes of borderline changes should be considered to be of poor prognosis.  相似文献   
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The aim of this study was to prospectively evaluate endoscopic ultrasonography and microscopic examination of duodenal bile in the diagnosis of cholecystolithiasis not detected by conventional ultrasonography. Forty five consecutive patients (26 females, 19 males, mean age: 50 years) with suspected cholecystolithiasis and at least two normal transcutaneous ultrasonography examinations were included. Endoscopic ultrasonographic criteria for the diagnosis of cholecystolithiasis were the presence of stones with or without acoustic shadowing or sludge. Criteria of microscopic examination of bile were cholesterol or bilirubinate crystals or spheroliths. Thirty three patients underwent cholecystectomy and lithiasis was found in gall bladder bile in 24. Twelve patients who were not operated on and were followed up (median: 17 months), had no evidence of cholecystolithiasis. Endoscopic ultrasonography and duodenal bile examination were 96% and 67% sensitive, respectively (p < 0.03). The specificity was not different (86 and 91%, respectively). None of the 16 patients with negative results in both procedures had evidence of cholecystolithiasis. It was found that for the diagnosis of cholecystolithiasis in patients with normal conventional ultrasonography, the sensitivity of endoscopic ultrasonography is higher than that of microscopic examination of duodenal bile. If endoscopic ultrasonography and microscopic examination of duodenal bile are negative, the risk of underdiagnosing cholecystolithiasis is negligible.  相似文献   
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Background: Tramadol hydrochloride (tramadol) is a synthetic opioid analgesic with a relatively weak affinity at opioid receptors. At analgesic doses, tramadol seems to cause little or no respiratory depression in humans, although there are some conflicting data. The aim of this study was to examine whether tramadol causes dose-dependent inhibitory effects on the ventilatory carbon dioxide response curve and whether these are reversible or can be prevented by naloxone.

Methods: Experiments were performed in cats under [alpha]-chloralose-urethane anesthesia. The effects of tramadol and naloxone were studied by applying square-wave changes in end-tidal pressure of carbon dioxide (Petco2; 7.5-11 mmHg) and by analyzing the dynamic ventilatory responses using a two-compartment model with a fast peripheral and a slow central component, characterized by a time constant, carbon dioxide sensitivity, time delay, and a single offset (apneic threshold).

Results: In five animals 1, 2, and 4 mg/kg tramadol (intravenous) increased the apneic threshold (control: 28.3 +/- 4.8 mmHg [mean +/- SD]; after 4 mg/kg: 36.7 +/- 7.1 mmHg;P < 0.05) and decreased the total carbon dioxide sensitivity (control: 109.3 +/- 41.3 ml [middle dot] min-1 [middle dot] mmHg-1) by 31, 59, and 68%, respectively, caused by proportional equal reductions in sensitivities of the peripheral and central chemoreflex loops. Naloxone (0.1 mg/kg, intravenous) completely reversed these effects. In five other cats, 4 mg/kg tramadol caused an approximately 70% ventilatory depression at a fixed Pet co2 of 45 mmHg that was already achieved after 15 min. A third group of five animals received the same dose of tramadol after pretreatment with naloxone. At a fixed Petco2 of 45 mmHg, naloxone prevented more than 50% of the expected ventilatory depression in these animals.  相似文献   

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Amoxicillin and clavulanic acid concentrations in gingival crevicular fluid   总被引:1,自引:0,他引:1  
Abstract The β-lactams are bactericidal antibiotics, but some of them may be inactivated by bacterial β-lactamases which destroy the β-lactam ring. The inactivation of amoxicilhn by β-Iactamases of gram negative anaerobic bacteria can be circumvented by the addition of clavulanic acid, a β-lactamases inhibitor. Thus, most of these bacteria are susceptible to this combination. The aim of this study was to investigate the concentrations of amoxicillin and clavulanic acid in gingival crevicular fluid (GCF). These concentrations were measured in 20 patients with rapidly progressive periodontitis 1 h after a dose of 500 mg (1 tablet Augmentin®) on day 0 and 1 h after the 10th intake on day 3. For the sampling of GCF, Periopapers® were introduced in 16 gingival sites per subject and time. The GCF volumes collected were estimated using the Periotron 6000®. A high performance liquid chromatography method has been developed for the determination of amoxicillin and clavulanic acid in microsamples (1 to 10 μl) of GCF. The concentrations of amoxicillin and clavulanic acid were respectively, 14.05 μg ml-1 and 0.40 μg ml-1 at day 0.13.93 μg ml-1 and 0.37 μg ml-1 at day 3. Effective levels of amoxicillin and clavulanic acid, well above the minimal inhibitory concentrations of some susceptible periodontal anaerobes (P. intermedia) involved in destructive periodontal diseases, are achieved following the multiple administration of amoxicillin combined with clavulanic acid.  相似文献   
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