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Spermine and spermidine, ubiquitous polyamines present in bacteria and animal cells, are also involved in cell growth. Since they interact with the double helix, they can stabilize the DNA molecule. Recent evidence of the antimutagenic and anticarcinogenic capacity of spermine has focused attention on the mechanism(s) by which such agents can protect cells from induced damages. In the present paper we show the ability of spermine and spermidine to decrease the level of sister chromatid exchanges induced in Chinese hamster ovary cells cultivated in vitro, by treating them with Psoralen + UVA irradiation (able to induce mainly monoadducts and DNA cross-links). Two different mechanisms of polyamine action can be invoked to explain the preservative activity of this class of agents. 相似文献
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P. Berloco R. Pretagostini L. Poli M. Caricato A. Speziale D. Cozzi L. Gallinaro D. Alfani R. Cortesini 《Transplant international》1994,7(S1):314-317
Abstract The use of unrelated living donors in kidney transplantation is still controversial but many transplant centres have accepted this procedure. The main argument against this approach is usually an ethical one. Because of this, at our institution we accept biologically unrelated donors only if they have an emotional closeness to the recipient. From January 1983 to October 1993, out of 654 kidney transplantations we performed at our institution, 364 kidney allografts were from living donors. Of these living donors, 245 were first-degree relatives of the recipient (LRD) while 119 were unrelated (LURD); 100 cases were spouses-wife to husband in 76 cases and husband to wife in 24 cases Statistical analysis of the results (chisquare) revealed actuarial patient and graft survival rates of 89.8% and 86.8% at 1 year, 82.9% and 72.3% at 5 years and 12.3% and 60.3% at 9 years, respectively. In our series, the result of living donor kidney transplantation in this group were similar to those obtained in the LRD group, while they were significantly better than those from cadaver donors (P = 0.003). In conclusion, cadaver organs given the shortage of kidney transplantation between spouses may be a good alternative and can be performed successfully, providing a "gift of life" for both the patient and the family. 相似文献
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Marchetti G Cozzi B Tavanti M Russo V Pellegrini S Fabiani O 《Journal of chemical neuroanatomy》2000,20(2):129-139
The present study reports the distribution of Neuropeptide Y (NPY)-immunoreactive neurons and fibers in the forebrain of the adult carp Cyprinus carpio L. Serial Nissl-stained sections were used for cytoarchitecture and identification of anatomical structures. Immunostaining of NPY-containing neurons and fibers was used as neurochemical marker and tool for comparison with other species, including the goldfish.The general outline of the cytoarchitecture of the carp forebrain is similar to that of other Cypriniformes. However, using NPY immunohistochemistry, we found several specific differences with the goldfish, especially in the diencephalon. In the hypothalamus of the carp NPY-immunoreactive (NPYir) neurons were identified in the n. dorsolateralis thalami, and in the n. ventralis lateralis thalami. In the same location, we observed the n. anterior hypothalami and the n. preglomerulosus pars lateralis, described in the goldfish, as parts of n. prerotundus. However, in the carp we were not able to identify a n. preglomerulosus pars medialis, a n. preglomerulosus pars medialis commissuralis and a n. glomerulosus. We describe a n. rotundus, in which we did not find substructures typical of the goldfish.Further differences with the goldfish, trout and salmon were also noted. 相似文献
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Hepatic arterial perfusion scintigraphy with Tc-99m-MAA. Use of a totally implanted drug delivery system 总被引:2,自引:0,他引:2
H A Ziessman J H Thrall P J Yang S C Walker E A Cozzi J E Niederhuber J W Gyves W D Ensminger M C Tuscan 《Radiology》1984,152(1):167-172
Tc-99m-MAA hepatic arterial perfusion scintigraphy ( HAPS ) using a totally implanted drug delivery system was employed for hepatic arterial chemotherapy in 147 patients (335 studies). Complete perfusion of the involved liver was seen in 88% of patients initially [more so in those with normal hepatic vascular anatomy (93%) than those with vascular variants (79%)] and remained good on follow-up. In 67 consecutive patients (95 studies), arteriovenous shunting to the lung ranged from 0.4 to 32% (mean, 6.2% +/- 4.1 S.D.). Uptake at the tip of the catheter was increased in 20% of patients, but good perfusion was usually maintained. A significant decrease in hepatic and/or extrahepatic perfusion associated with a "hot spot" at the tip of the catheter indicated hepatic arterial thrombosis. Extrahepatic perfusion was seen in 14% of cases, usually in the distribution of the stomach, small bowel, and spleen. Significant symptoms of drug toxicity were seen in 70% of patients with extrahepatic perfusion, compared to 19% of those without it. 相似文献
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Valentina Mazzotta Alessandro Cozzi Lepri Francesca Colavita Silvia Rosati Eleonora Lalle Claudia Cimaglia Jessica Paulicelli Ilaria Mastrorosa Serena Vita Lavinia Fabeni Alessandra Vergori Gaetano Maffongelli Fabrizio Carletti Simone Lanini Emanuela Caraffa Eugenia Milozzi Raffaella Libertone Pierluca Piselli Enrico Girardi AnnaRosa Garbuglia Francesco Vaia Fabrizio Maggi Emanuele Nicastri Andrea Antinori INMI COVID- Outpatient Treatment Study Group 《Journal of medical virology》2023,95(1):e28186
9.
Within the frame of PRISMA 1 "Biogeochemical cycles" research project (April 1995-January 1996) the quantities and the compartments of dissolved nitrogen and phosphorus have been studied in the northern Adriatic basin, considering also the organic pools. The research aimed to provide a better understanding of nutrient availability and to investigate the possible factors which promote the phenomenon of mucilage formation. For this purpose, the availability and the ratios between dissolved nitrogen and phosphorus considering both inorganic and organic fractions have been studied in relation to variations of river outflow and of biological activities. The results obtained reveal the large importance of organic nitrogen (annual average 16 microM) and phosphorus (annual average 0.13 microM) in contributing to the total nutrient availability (annual average total dissolved nitrogen: 29 microM and phosphorus: 0.18 microM) and the pronounced seasonal variability mainly ascribable to biological processes of uptake and remineralization. Furthermore, beside the well documented unbalanced ratio between inorganic nitrogen and phosphorus, the results obtained point out, for the first time, the unbalance also in the organic compartment (ratio between organic nitrogen and phosphorus ranges between 50 and 530), whose consequences might be important in relation to the phenomenon of mucilage formation. 相似文献