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71.
S Pichini R Pacifici I Altieri M Pellegrini P Zuccaro 《Journal of analytical toxicology》1999,23(5):343-348
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
72.
Regazzi MB Rinaldi M Molinaro M Pellegrini C Calvi M Arbustini E Bellotti E Bascapè V Martinelli L Viganò M 《Therapeutic drug monitoring》1999,21(1):2-7
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
73.
Guidotti M. Ciccone A. Garavaglia P. Pellegrini G. 《The Italian Journal of Neurological Sciences》1996,17(2):153-155
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.相似文献
74.
Richard M. Smiley Eugene Ornstein Eugene J. Pantuck Carol B. Pantuck Richard S. Matteo 《Journal canadien d'anesthésie》1991,38(8):965-968
The metabolism of isoflurane and the investigational volatile anaesthetic desflurane to fluoride ion was examined in 25 surgical patients. The patients were randomly assigned to four groups, to receive isoflurane or desflurane at either 0.65 MAC or 1.25 MAC. Anaesthesia was induced in all patients with thiopentone and midazolam and included nitrous oxide 60% in addition to the volatile agent. Blood was drawn before induction and at the end of the operation for determination of serum fluoride ion concentration. Plasma fluoride ion concentrations increased (+ 1.36 +/- 0.93 microM, P less than 0.01) in patients receiving isoflurane but were unchanged (-0.13 +/- 0.50 microM) in patients receiving desflurane. Metabolic release of fluoride ion is less with desflurane than with isoflurane during administration of the anaesthetics to surgical patients, and is unlikely to be of clinical significance. 相似文献
75.
76.
77.
Antitumor vaccination of patients with glioblastoma multiforme: a pilot study to assess feasibility, safety, and clinical benefit. 总被引:5,自引:0,他引:5
Hans Herbert Steiner Matteo Mario Bonsanto Philipp Beckhove Michael Brysch Karsten Geletneky Rezvan Ahmadi Rebecca Schuele-Freyer Paul Kremer Golamreza Ranaie Dejana Matejic Harald Bauer Marika Kiessling Stefan Kunze Volker Schirrmacher Christel Herold-Mende 《Journal of clinical oncology》2004,22(21):4272-4281
PURPOSE: Prognosis of patients with glioblastoma is poor. Therefore, in glioblastoma patients, we analyzed whether antitumor vaccination with a virus-modified autologous tumor cell vaccine is feasible and safe. Also, we determined the influence on progression-free survival and overall survival and on vaccination-induced antitumor reactivity. PATIENTS AND METHODS: In a nonrandomized study, 23 patients were vaccinated and compared with nonvaccinated controls (n = 87). Vaccine was prepared from patient's tumor cell cultures by infection of the cells with Newcastle Disease Virus, followed by gamma-irradiation, and applied up to eight times. Antitumor immune reactivity was determined in skin, blood, and relapsed tumor by delayed-type hypersensitivity skin reaction, ELISPOT assay, and immunohistochemistry, respectively. RESULTS: Establishment of tumor cell cultures was successful in approximately 90% of patients. After vaccination, we observed no severe side effects. The median progression-free survival of vaccinated patients was 40 weeks (v 26 weeks in controls; log-rank test, P = .024), and the median overall survival of vaccinated patients was 100 weeks (v 49 weeks in controls; log-rank test, P < .001). Forty-five percent of the controls survived 1 year, 11% survived 2 years, and there were no long-term survivors (> or = 3 years). Ninety-one percent of vaccinated patients survived 1 year, 39% survived 2 years, and 4% were long-term survivors. In the vaccinated group, immune monitoring revealed significant increases of delayed-type hypersensitivity reactivity, numbers of tumor-reactive memory T cells, and numbers of CD8(+) tumor-infiltrating T-lymphocytes in secondary tumors. CONCLUSION: Postoperative vaccination with virus-modified autologous tumor cells seems to be feasible and safe and to improve the prognosis of patients with glioblastomas. This could be substantiated by the observed antitumor immune response. 相似文献
78.
Donato Gemmati Alessia Ongaro Gian L Scapoli Matteo Della Porta Silvia Tognazzo Maria L Serino Eros Di Bona Francesco Rodeghiero Giuseppe Gilli Roberto Reverberi Angelo Caruso Michela Pasello Agnese Pellati Monica De Mattei 《Cancer epidemiology, biomarkers & prevention》2004,13(5):787-794
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation. 相似文献
79.
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