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排序方式: 共有6875条查询结果,搜索用时 281 毫秒
1.
Rocco Spagnuolo Alessandro Corea Mariantonietta Blumetti Alessia Giovinazzo Massimiliano Serafino Caterina Pagliuso Raffaele Pagnotta Grazia Curto Cristina Cosco Vincenzo Cosco Rosellina Margherita Mancina Pietro Garieri Anna Papaleo Laura Grande Anna Barilaro Eugenio Garofalo Andrea Bruni Patrizia Doldo 《Journal of advanced nursing》2020,76(11):2993-3002
2.
Eugenia Cordelli Anna Maria Fresegna Alessia D'Alessio Patrizia Eleuteri Marcello Spanò Francesca Pacchierotti Paola Villani 《Toxicological sciences》2007,99(2):545-552
The increasing request of chemical safety assessment demands for the validation of alternative methods to reduce the resort to animal experimentation. Methods that evaluate reproductive toxicity are among those requiring the largest use of animals. Presently, no validated in vitro alternative exists for the assessment of reproductive toxicity. Mammalian sperm are sensitive targets of DNA-reactive chemicals, which form premutagenic adducts. Here, we propose a new method based on comet assay to detect DNA damage induced by potential germ cell mutagens in bull sperm available from assisted reproduction practices. In somatic cells, chemical-induced adducts can be revealed by comet assay that detects DNA breaks produced during adduct repair. Mature sperm, however, are devoid of repair enzymes, and adducts are processed only after fertilization. For this reason, comet assay is not sensitive to detect DNA lesions induced in sperm by most chemicals. To overcome such limitation, we developed a modified comet assay based on the addition of a protein extract from HeLa cells to agarose-embedded sperm on microscopic slides. To test the method, sperm were treated in vitro with methyl methanesulfonate (MMS) or melphalan (MLP) and comet assay was conducted both with and without protein supplementation. No effect of MMS or MLP was detected without protein supplementation; on the contrary, a clear-cut dose-dependent effect was measured after addition of the cell extract. These results represent a proof of concept of a novel in vitro mutagenicity test on sperm that could offer a promising approach to complement previously validated in vivo germ cell genotoxicity assays. 相似文献
3.
Carmine Zoccali Renke Maas Sebastiano Cutrupi Patrizia Pizzini Piero Finocchiaro Francesco Cambareri Vincenzo Panuccio Carmela Martorano Friedrich Schulze Giuseppe Enia Giovanni Tripepi Rainer Boger 《Nephrology, dialysis, transplantation》2007,22(3):801-806
BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level. 相似文献
4.
5.
Megakaryocytic Progenitors Can Be Generated Ex Vivo and Safely Administered to Autologous Peripheral Blood Progenitor Cell Transplant Recipients 总被引:9,自引:1,他引:8
6.
E Damiani M T Cattaneo C Sessa E Zucca F Cavalli A Bertolini A Libretti R Beretta 《Tumori》1987,73(5):487-491
Urinary excretion of N-acetyl-beta-glucosaminidase (NAG) is an early marker of nephrotoxicity. NAG activity was assayed by the fluorimetric method of Leaback and Walker in 17 patients treated (22 courses) with carboplatin (CBDCA, 220-550 mg/m2) before infusion and 24, 48, 72 and 96 h after. Increased excretion of NAG, a sensitive index of renal tubular damage, was observed following 10 of the 22 courses. A transient increase in plasma creatinine and/or abnormal proteinuria was observed in 6 cases. Impaired renal function prior to therapy seems to be a predisposing factor to the nephrotoxicity. 相似文献
7.
8.
Luigi Paolo Badano Maria C Albanese Paola De Biaggio Patrizia Rozbowsky Daniela Miani Claudio Fresco Paolo M Fioretti 《Journal of the American Society of Echocardiography》2004,17(3):253-261
Prevalence of isolated left ventricular (LV) diastolic dysfunction has been reported to be as high as one-third of all heart failure (HF) cases, with an increasing prevalence in the elderly population. However, there is a paucity of prospective data about the prevalence and prognosis of isolated LV diastolic dysfunction in an unselected population of patients hospitalized with HF. Therefore, we prospectively evaluated 179 consecutive patients discharged from our hospital with HF to assess the prevalence of systolic versus diastolic LV dysfunction among patients hospitalized with HF and to compare their demographics, clinical features, self-perceived quality of life (QOL), and 6-month readmission rate and mortality. Among them, 133 (59% men, median age 74 years) showed in sinus rhythm and had no significant primary valvular disease. LV diastolic dysfunction was diagnosed on the basis of the European Study Group on Diastolic HF echocardiographic criteria. QOL was assessed at hospital discharge and 6-month follow-up visit using the Minnesota Living with HF questionnaire. Survival of patients with HF was compared with that of age- and sex-matched general population. In all, 29 patients (22%) had isolated LV diastolic dysfunction and 102 (78%) had prevalent LV systolic dysfunction (ie, LV ejection fraction = 45%). There was no difference in age, sex, or New York Heart Association functional class between patients with LV diastolic or systolic dysfunction. QOL scores were similar between the 2 patient groups with HF both at discharge (39.4 and 34) and at 6-month visit (10.4 and 10.4). Both 6-month readmission rate (48% and 48%) and median inhospital length-of-stay during readmissions (10 days and 10 days) were similar between the 2 patient groups with HF. Finally, 6-month survival, adjusted for age and sex, was similar between patients with LV diastolic or systolic dysfunction (hazard ratio 0.68; 95% confidence interval 0.20-2.35). Using standardized echocardiographic criteria, isolated LV diastolic dysfunction among unselected patients hospitalized with HF was less than previously reported. Patients with HF and isolated diastolic dysfunction showed similar clinical symptoms, self-perceived QOL, readmission rate, and 6-month mortality to patients with prevalent LV systolic dysfunction. 相似文献
9.
Angela Alama Federica Barbieri Renato Spaziante Cristina Bruzzo Patrizia Dadati Alessandra Dorcaratto Jean Louis Ravetti 《Journal of clinical neuroscience》2007,14(4):355-358
Forty-four evaluable patients with intracranial meningiomas were assessed for the expression of the cell-cycle regulator cyclin D1 and of proteins involved in proliferation and apoptosis such as PCNA, MIB-1, p53 and bcl-2. Analyses were carried out by western blot and immunohistochemistry after immediate processing of fresh tumor specimens. By western blot, expression of cyclin D1 significantly correlated with p53 (p=0.02) and with proliferative activity, as assessed by PCNA expression (p=0.0009). By immunohistochemistry, a significant relationship between cyclin D1 and the proliferation marker MIB-1 was confirmed (p=0.05), whereas significance with bcl-2 expression was not found (p=0.01). Moreover, although the association with tumor grade appeared of borderline statistical significance (p=0.07), all the grade II/III meningiomas showed increased expression of cyclin D1 and high proliferative activity. In conclusion, data from this preliminary study seem to suggest a potential value of the combined expression of cyclin D1 and proliferation indicators in defining subgroups of meningiomas with a more aggressive biological behavior. 相似文献
10.
In rats bled to hypovolemic shock, the intracerebroventricular injection of hemicholinium-3 (20 micrograms/rat) completely prevented the shock reversal induced by the intravenous injection of ACTH (1-24) (160 micrograms/kg), but had no influence on the shock reversal induced by the intravenous injection of physostigmine (70 micrograms/kg). These data indicate that brain cholinergic neurons are involved in the anti-shock effect of ACTH-peptides, but not in that of centrally acting cholinergic drugs. 相似文献