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This study investigates the mdm2 gene status and expression in 66 surgically resected human breast carcinomas, with correlations with clinico-pathological and biological data (histological type, grading, steroid receptor status, p53 expression, proliferative activity). Four (7.7 per cent) out of 52 informative cases bear mdm2 gene amplification (four- to ten-fold) and 8 (15.4 per cent) of 52 cases showed borderline amplification (three-fold). Nine (13.6 per cent) out of 66 cases showed strong mdm2 nuclear immunoreactivity. Twenty-seven (40.9 per cent) cases showed isolated mdm2 reactive nuclei. All cases with clear amplification showed a high percentage of mdm2 immunoreactive nuclei. The relationship between gene amplification and mdm2 protein expression is highly significant (P<0.0001). No association was observed between mdm2 gene amplification and any of the considered clinico-pathological and biological parameters, while mdm2 immunoreactivity showed a significant association only with oestrogen receptor immunoreactivity (P=0.009). p53 expression was associated neither with mdm2 gene amplification nor with mdm2 immunoreactivity. It could be tempting to hypothesize that the evaluation of the combined mdm2/p53 immunohistochemical phenotype in human breast carcinoma could give us better prognostic information than the evaluation of the expression of the p53 protein alone.  相似文献   
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The soluble form of carcinoembryonic antigen (sCEA), an oncofetal glycoprotein, is frequently produced by human epithelial-tumor cells, particularly of colorectal origin, and evaluated as a prognostic index of tumor progression and patient survival. sCEA molecules are often present at high concentrations in the peripheral blood of colorectal cancer patients, but the function and significance of this are not well understood. Reported data have demonstrated that sCEA can interfere in NK-cell/tumor-cell interaction by drastically reducing the lysis of tumor cells in a dose-dependent manner and can also suppress T and B cell functions. The aim of our study was to evaluate this situation in colorectal cancer by determining peripheral blood immunological parameters in a group of patients and healthy subjects. We evaluated the interleukin (IL)-2, interferon (IFN) gamma, IL-4, sIL-2R and IL-10 levels in the serum and the release of IFN gamma, IL-4 and IL-10 from peripheral blood mononuclear cells (PBMC); the PBMC expression of CD3, CD16 and CD19 phenotypic antigens; the PBMC proliferative responses to IL-2, IL-2 + anti-CD3 monoclonal antibody (mCD3) and mCD3. The statistical evaluation of our overall results strongly indicates that the high level of the sCEA molecules in the patient's serum might act as a suppressive factor for NK and TH1 immunocompetent cells. This may be the cause of sCEA involvement in tumor progression, and indicates the possibility of an improvement in cancer treatment through its manipulation.  相似文献   
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An analytical method for the determination of heroin, 6-monoacetylmorphine, morphine, codeine, cocaine, benzoylecgonine, and cocaethylene in human hair using gas chromatography-tandem mass spectrometry is presented. The analytes were extracted from finely cut hair with methanol at 56 degrees C for 18 h in the presence of nalorphine as the internal standard. After the incubation, methanol was evaporated to dryness, and all the analytes, except heroin, cocaine, and cocaethylene, were converted to their trimethylsilyl derivatives. The reaction products were identified and quantitated using product ions formed from the parent ions by collision-induced dissociation in the ion-trap mass spectrometer. This method provided excellent sensitivity and specificity for analytes at the concentrations usually found in the keratin matrix.  相似文献   
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Clinical pharmacokinetics of tacrolimus in heart transplant recipients   总被引:6,自引:0,他引:6  
We report pharmacokinetic data on tacrolimus in 14 heart transplant patients (2 women, 12 men). The median age and the median body weight were 55.5 years (range, 23-61 years) and 67.0 kg (55-79 kg), respectively. All patients were maintained on a triple-drug protocol (tacrolimus, azathioprine, and prednisone), with a 7-day antithymocyte globuline induction. The first tacrolimus dose, administered orally 1 to 5 days posttransplant, ranged from 0.03 to 0.4 mg/kg (median = 0.052 mg/kg). The maintenance dose ranged from 0.03 to 0.13 mg/kg/day (administered in two equal doses) to achieve blood levels of 5 of 20 ng/ml, as determined by a microparticle enzyme immunoassay (MEIA). Whole blood samples were drawn just before, at 0.5 hour, and at 1, 2, 3, 4, 6, 8, 10, and 12 hours after the administration of the first dose; trough levels were measured thereafter.The mean oral clearance (CL/F) and apparent volume of distribution (Vd/F) averaged 0.21+/-0.08 L/hour/kg and 2.4+/-0.8 L/kg while the half-life averaged 8.7+/-3.5 hours. Tacrolimus accumulation index during chronic therapy (Rac = Cmin(steady state)/Cmin(first dose) normalized to the same dose) averaged 1.3. Eighty-eight percent of the trough blood levels measured in our patients were within 5 and 20 ng/ml. The incidence of rejection in the study population was extremely low: a prevalence of grade 2 rejection or more, of 0.4+/-0.8 episodes/ patient was observed after a follow-up period of 8.8+/-2.2 months. Only one patient experienced severe renal toxicity, probably because of his preoperative precarious hemodynamic status. Pharmacokinetic data suggest that maintenance tacrolimus daily dose should be equal to 0.1 mg/kg/day to obtain trough blood concentrations of approximately 10 ng/ml. Inter- and intra-patient variability of tacrolimus blood concentration should be expected and justify careful monitoring.  相似文献   
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We followed up 107 patients experiencing a first-ever ischemic stroke after having been affected by essential hypertension for at least one year, in order to analyze the phenomenon of post-stroke blood pressure lowering. Of the 82 patients still surviving after three months of follow-up, 44 (54%) had normal arterial blood pressure values. There were no significant differences between these normotensive patients and the 38 with high blood pressure in terms of cerebrovascular risk factors or disability, but blood pressure normalized in 34 of the 54 patients experiencing a carotid stroke (63%) and in only 10 of the 28 experiencing vertebrobasilar stroke (36%) (p=0.035). These data may offer a starting point for further studies of the neurogenesis of arterial hypertension.
Sommario Al fine di analizzare il fenomeno della normalizzazione della pressione arteriosa dopo ictus cerebrale in pazienti prima ipertesi, abbiamo osservato 107 soggetti con primo ictus ischemico, che erano già precedentemente affetti da ipertensione arteriosa da almeno un anno. Degli 82 (77%) sopravvissuti a tre mesi di follow-up, 44 (54%) hanno mostrato una normalizzazione della pressione arteriosa. L'incidenza di fattori di rischio per malattia cerebrovascolare e disabilità grave non è risultata significativamente diversa nel gruppo degli ipertesi rispetto ai normotesi. Tuttavia la normalizzazione della pressione arteriosa è stata osservata in 34 dei 54 pazienti con ictus carotideo (63%) e solo in 10 dei 28 con ictus vertebrobasilare (36%) (p=0.035). Riteniamo che tali dati offrano uno spunto per ulteriori ricerche sulla genesi neurogena dell'ipertensione arteriosa essenziale.
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Morphea is an inflammatory cutaneous disease that can be mistaken for a soft-tissue neoplasm. The authors report two cases of morphea that were resected surgically before the histological diagnosis of morphea was rendered. One of the patients had a recurrence of morphea around her large surgical scar. They present these cases to alert surgeons to the pitfall of inappropriate surgical treatment of an inflammatory condition.  相似文献   
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