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71.
72.
Dr. Franco Zunino Brunella Barbieri Ornella Bellini Anna Maria Casazza Cristina Geroni Fernando Giuliani Antonio Ciana Giorgio Manzini Franco Quadrifoglio 《Investigational new drugs》1986,4(1):17-23
Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines. 相似文献
73.
F Parazzi B Faravelli L Gallo M Nosenzo A Razzetti D Barone R Bandelloni E D'Amore 《Tumori》1987,73(1):33-36
The usefulness of tumor marker assay in pleural effusions for differential diagnosis is still debated. From the observation of common antigens on tissue polypeptide antigen (TPA) and keratins 8, 18 and 19 and vimentin, all substances contained in normal and neoplastic mesothelium, we felt it opportune to evaluate the use of TPA assay in 105 pleural effusions (46 benign and 59 malignant). The values were much higher than those found in blood. In hydrothorax the median value was 454 U/l (range, 59-1923), in exudative effusions 846 U/l (range, 258-4485), in metastatic pleural effusions 1277 U/l (range, 58-32352) and in mesotheliomas 7705 (range, 759-16000). The maximum value found in nonmalignant effusions was 4485 U/l; this value was taken as a cutoff level, so only 29.9% of the tumors were positive to the test. Our results showed this assay to be not very important for a differential diagnosis of malignant and nonmalignant pleural effusions. Nevertheless, the different TPA patterns in mesotheliomas (66.6% positive) and metastatic pleural effusions (15.9%) suggest that further studies are warranted. 相似文献
74.
G Tarzia E Occelli N Corsico L Gallico F Luzzani D Barone 《Il Farmaco; edizione pratica》1989,44(1):17-28
Some 2-aminoalkyl-8-chloro- and 2-aryl-1,2,4-triazolo[3,4-a]-phthalazine-3-(2H)-ones were synthesized and preliminarily tested in vitro and in vivo as potential benzodiazepine-receptor (BZRs) ligands. 2-Aryl-1,2,4-triazolo[3,4-a]-phthalazine-3(2H)-ones displaced in vitro 3H-diazepam (3H-DZ) from rat brain specific binding sites with Ki (nM) comparable to DZ and chlordiazepoxide used as reference compounds. The specific binding of the triazolones of this study was not enhanced in vitro by 4-aminobutyric acid (GABA) and in vivo they did not show any activity in counteracting the pentylenetetrazole (PTZ) induced convulsions (mice). One of these compounds (IV a) antagonized the effects of DZ in the bicuculline (BIC) induced convulsions test (mice) and the DZ induced muscle relaxant effects in the horizontal wire test. 相似文献
75.
Successful Liver and Kidney Transplantation From Cadaveric Donors With Left-Sided Bacterial Endocarditis 总被引:1,自引:0,他引:1
Francisco Caballero Antonio Lopez-Navidad Milagrosa Perea Catiana Cabrer Lluis Guirado Ricard Solà 《American journal of transplantation》2005,5(4):781-787
Bacterial infections are frequent in cadaveric organ donors and can be transmitted to the transplantation recipient, which could have devastating consequences for the recipients if adequate preventive measures are not adopted.
From the 355 consecutive brain dead cadaveric organ donors procured at our center in the last four years, 2000–2003, four of them (1.1%) had bacterial endocarditis as cause of death. The bacteria responsible for the endocarditis were Staphylococcus epidermidis, coagulase-negative Staphylococcus , Staphylococcus hominis and Streptococcus viridans , respectively. We performed five kidney and two liver transplantations on seven recipients. All donors and recipients received antibiotic treatment against the germ causing the respective endocarditis.
Infection by the bacteria responsible for the endocarditis in the respective donors was not transmitted to any of the recipients. Six of the seven recipients were alive with normal-functioning grafts after between 13 and 24 months' follow-up. Transplantectomy was performed on one kidney recipient due to thrombosis of the renal vein of the graft not related to the endocarditis.
Liver and kidney transplantation from donors dying from bacterial endocarditis can be performed without causing the transmission of infection to the recipient or the dysfunction of the graft. 相似文献
From the 355 consecutive brain dead cadaveric organ donors procured at our center in the last four years, 2000–2003, four of them (1.1%) had bacterial endocarditis as cause of death. The bacteria responsible for the endocarditis were Staphylococcus epidermidis, coagulase-negative Staphylococcus , Staphylococcus hominis and Streptococcus viridans , respectively. We performed five kidney and two liver transplantations on seven recipients. All donors and recipients received antibiotic treatment against the germ causing the respective endocarditis.
Infection by the bacteria responsible for the endocarditis in the respective donors was not transmitted to any of the recipients. Six of the seven recipients were alive with normal-functioning grafts after between 13 and 24 months' follow-up. Transplantectomy was performed on one kidney recipient due to thrombosis of the renal vein of the graft not related to the endocarditis.
Liver and kidney transplantation from donors dying from bacterial endocarditis can be performed without causing the transmission of infection to the recipient or the dysfunction of the graft. 相似文献
76.
77.
Eugenio Neri Lucio Barabesi Dimitrios Buklas Luca A. Vricella Antonio Benvenuti Enrico Tucci Carlo Sassi Massimo Massetti 《European journal of cardio-thoracic surgery》2005,28(6):857-863
Objective: Increased dimension of the aortic root and proximal aorta is considered a significant risk factor for catastrophic events that involve the ascending aorta. The objective of this study was to determine the possible correlation between pre-dissection aortic diameter and the occurrence of Stanford type A aortic dissection. Methods: Samples of dissected ascending aortas were obtained from 220 patients at the time of their operation. Two groups were identified: patients with connective tissue disorders (Group 1, n = 94) and those without (Group 2, n = 126). Measurements of the true (intimal) lumen were conducted and extrapolated as reliable approximation of pre-dissection aortic diameter. The possible association of intimal diameter with anthropometric and demographic data was analyzed. Results: Median aortic diameter was, respectively, 41.8 and 41.3 mm for patients with and without connective tissue disorders (41.4 mm for the entire cohort). Data analysis indicated that 57% of patients had aortic diameter above 40 mm, while patients with frank aneurysm accounted only for 10%; this proportion was higher in Group 1 compared to Group 2 (17.2% vs 4.7%). Poor or no correlation was demonstrated between aortic size and any of the anthropometric or demographic variables essayed. Significant subgroup differences were found among patients with a history of cigarette smoking, hypertension, diabetes, chronic renal insufficiency, and bicuspid aortic valve. Conclusion: Although aortic diameter remains a strong indication for preventive surgery in patients with inherited connective tissue disorders, acute aortic dissection occurs rarely in the setting of true ascending aortic aneurysms, and despite normal or near-normal aortic size in more than one-third of subjects. Dissection superimposing on small aortic diameters can be regarded as an expression of substantial functional tissue susceptibility to aortic catastrophic events. 相似文献
78.
Vittorio Palmieri Emiliano Antonio Palmieri Aldo Celentano 《European heart journal》2007,28(20):2430-2431
79.
Antonio Bobbio Alfredo Chetta Paolo Carbognani Eveline Internullo Alessia Verduri Giulianoezio Sansebastiano Michele Rusca Dario Olivieri 《European journal of cardio-thoracic surgery》2005,28(5):754-758
OBJECTIVE: Pulmonary Function Tests (PFT) and Cardio-Pulmonary Exercise Testing (C-PET) are useful to evaluate operability in functionally compromised patients. Although modifications of PFT and C-PET after lung surgery have been widely explored, little information exists as to modifications of exercise capacity in COPD patients undergoing lung resection. We prospectively analyzed the changes in PFT and C-PET in patients with COPD after a pulmonary lobar resection. METHODS: From January 2003 to March 2004 all patients scheduled for lung resection were considered for participation in the study protocol. Those patients with a preoperative diagnosis of COPD on PFT were explored through a C-PET. Only patients who had undergone a lobar pulmonary resection were subsequently considered; these patients had a new complete cardio-respiratory evaluation 3 months after surgery. The pre- and postoperative values compared were those of FEV1, TLC, DLCO, VO2max, and VE/VCO2. Data are expressed as mean +/- standard deviation (SD). Statistic evaluation was made using the Wilcoxon test. RESULTS: During this period 11 patients completed the study protocol. Ten patients underwent surgery for NSCLC and one for a pulmonary aspergilloma. Nine lobectomies and two bilobectomies were performed. In the study population, the preoperative mean value of FEV1 resulted as being 53% (SD+/-20) of the predicted mean value, that of TLC 120% (SD+/-35) and that of DLCO 65% (SD+/-27). The preoperative mean value of VO2max resulted as being 17.8 ml/Kg/min (SD+/-3.25) and mean VE/VCO2 resulted as being 35.7 (SD+/-4). Three months after surgery the measured mean value of FEV1 was 53% (SD+/-18), that of TLC was 99% (SD+/-24) and that of DLCO 52% (SD+/-18). The mean value of VO2max resulted as being 14.1 ml/Kg/min (SD+/-3.04) and that of VE/VCO2 was 42.5 (SD+/-12.8). Statistical analysis of PFT values showed that FEV1 and DLCO were not significantly modified (P > 0.05); in contrast, TLC had significantly decreased (P = 0.008). VO2max had significantly decreased (P = 0.004) and VE/VCO2 had significantly increased (P = 0.018). CONCLUSIONS: Three months after a lobar pulmonary resection, patients with COPD were found to have a significant decrease in exercise tolerance. PFT alone can underestimate the postoperative loss of exercise capacity through exercise. 相似文献
80.
Giangennaro Coppola Francesca Felicia Operto Gianfranca Auricchio Alessandra D'Amico Delia Fortunato Antonio Pascotto 《Epileptic Disord》2007,9(2):145-148
A child had the characteristic clinical and EEG pattern of migrating partial seizures in infancy with left temporal lobe atrophy, hippocampal sclerosis and cortical-subcortical blurring.Seizures were drug-resistant, with recurring episodes of status epilepticus. The child developed microcephaly with arrest of psychomotor development. Focal brain lesions, in the context of migrating partial seizures, have not been previously reported.[Published with video sequences]. 相似文献