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排序方式: 共有650条查询结果,搜索用时 15 毫秒
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M. Gaudet F. Villani M. Cherubini I. Beritognolo I. Dalla Ragione S. Proietti 《Plant biosystems》2019,153(4):491-497
In central Italy, Prunus cerasus var. austera is cultivated as small stands or scattered trees in marginal areas for the production of jam and wine. Thanks to the healthy attributes of its products and its ability to grow in different environmental conditions, this variety has gained new interest in the development of marginal areas. We assessed the level of the genetic variability of P. cerasus var. austera germplasm from central Italy and identified a ‘core collection’ representative of the present genetic diversity. A total of 161 trees, morphologically identified as var. austera, and one tree, identified as var. caproniana were collected and genotyped by 14 SSRs. Two individuals provided by a commercial plant nursery, one of P. cerasus var. caproniana and one of P. cerasus var. austera, were used as control. Thirteen SSRs presented private alleles in austera. Seven individuals morphologically identified as austera revealed private alleles specific to caproniana. The PCoA and Bayesian clustering analysis showed a main genetic group including var. austera, while a second group included all the caproniana-like genotypes. A core collection of 31 trees (46% of austera genotypes) was selected. This study can be considered as a starting point for future investigations on this variety. 相似文献
3.
Characterization and localization of cis-diamminedichloro-platinum(II) adducts on a purified oligonucleotide containing the codons 12 and 13 of H-ras proto-oncogene. 下载免费PDF全文
M J Pillaire G Villani J S Hoffmann A M Mazard M Defais 《Nucleic acids research》1992,20(24):6473-6479
The use of substrates containing well defined adducts at precise sites, is required to perform a careful analysis of the toxic and mutagenic potential of a lesion. As a first step in this direction the octamer 5'-d(CCGGCGGT), containing the sequence of the codons 12 d(GGC) and 13 d(GGT) of the human H-ras gene, was reacted with the antitumoral drug cis-diamminedichloroplatinum(II). The platinated products have been purified by HPLC. A first set of experiments, including enzymatic digestions with nuclease P1 followed by alkaline phosphatase and acid-catalysed hydrolysis, allowed us to determine which bases were engaged in the cis-DDP lesions. Our results indicate that only guanine residues were chelated with cisplatin to yield bifunctional adducts. Furthermore, by performing enzymatic digestions with phosphodiesterases, we have located the adducts with respect to the 5' end of the octamer. Among the purified and characterized platinated oligonucleotides, three present a particular interest, since we have shown here that the cis-d(GpG) adduct is precisely situated either at the d(GGC) or at the d(GGT) or at both sites of their sequence. 相似文献
4.
R Fiorella G Assennato V Di Nicola M Troia G A Colucci L Resta 《Bollettino della Società italiana di biologia sperimentale》1991,67(2):199-205
The presence of inflammatory reaction, plasma cells, and eosinophils in peritumoral connective tissue and in neoplastic stroma was evaluated with morphometrical method in 181 patients affected by laryngeal carcinoma. A logistic multiple regression model was applied making it with the use of an independent variable represented by the "infiltrating" or "expansive" types of tumor growth, in order to evaluate the probability of nodal metastatsis of each parameter. The results suggest an inverse correlationship between plasma cells and inflammatory infiltration and incidence of nodal metastatsis only in the comparison of the extreme conditions: those with scarce infiltration versus the ones with large infiltration. Inflammatory or plasmacellular infiltration may represent both a defense mechanism against cancer and an aspecific or allergic reaction. The eosinophilic infiltration shows no value in the prevention of nodal involvement. 相似文献
5.
Fiorella D'Anna Michele De Luca Ranieri Cancedda Antonio Zicca Adriano T. Franzi 《The Histochemical journal》1988,20(12):674-678
Summary Human epidermal keratinocytes grown in culture and at different stages of differentiation are shown to be viably separated by elutriation. A specific fraction enriched in melanocytes was obtained. Elutriation of cells obtained fromin vitro cultured epithlium could prove useful in studies concerning the biochemistry and molecular markers of cells isolated from normal epithelium and from different pathologies. 相似文献
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M Audisio D Dante F Fidanza C Villani G Rulli 《Bollettino della Società italiana di biologia sperimentale》1985,61(2):295-301
In this study plasma levels of vitamin A, carotenoids, retinol binding protein (RBP), prealbumin (PA), HDL-and total cholesterol were determined in 19 female subjects with cervical dysplasia and compared to those of the healthy female subjects described in our previous research. Plasma levels of vitamin A and carotene were determined by a spectrophotometric method using trifluoroacetic acid, plasma RBP and PA by single radial immunodiffusion and HDL- and total cholesterol by enzymatic colorimetry. Plasma mean values of vitamin A and HDL-cholesterol were lower (P less than 0.05 and P less than 0.01, respectively) than in the control group. On the contrary total cholesterol was higher (P less than 0.01) in the patients than in the control group. Vitamin A plasma levels were significantly related (P less than 0.01) to RBP and PA. No significant statistical correlation was found between the severity of the dysplasia and vitamin A plasma levels. 相似文献
8.
Evidence for two waves of induction of DNA enzymes in stimulated human lymphocytes 总被引:5,自引:3,他引:2 下载免费PDF全文
Guido C. F. Pedrali Noy Leda Dalpra Antonia M. Pedrini Giovanni Ciarrocchi Elena Giulotto Fiorella Nuzzo Arturo Falaschi 《Nucleic acids research》1974,1(9):1183-1199
The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background. 相似文献
9.
Fabrizio Villani Milena Galimberti Elena Monti Francesco Piccinini Enrica Lanza Annalinda Rozza Luigia Favalli Paola Poggi Franco Zunino 《Free radical research》1990,11(1):145-151
The effects of two sulfhydryl compounds, glutathione (GSH) and N-acetylcysteine (NAC), on the cardiotoxicity of doxorubicin (DXR) were tested on in vitro and in vivo models. DXR was administered to rats as 4 weekly i.v. doses of 3mg/kg. GSH (1.5 mmoles/kg), given i.v. 10 min before and 1 hr after DXR, was found to prevent the development of the delayed cardiotoxic effects of DXR, as assessed by electrocardiographic and mechanical parameters, as well as by histological examination of left ventricular preparations. In contrast, equimolar oral doses of NAC (1 hr before and 2hrs after DXR) were found to be ineffective. Both GSH and NAC prevented the negative inotropic effect produced by DXR on isolated rat atria. A good correlation exists between the cardioprotective effects of the two agents and their ability to enhance the non-protein sulfhydryl group content of the myocardium. Differences observed in vivo between GSH and NAC might be accounted for by pharmacokinetic factors. 相似文献
10.
F. Villani O. Pepe G. Mauriello G. Moschetti L. Sannino S. Coppola 《Letters in applied microbiology》1996,22(5):357-360
F. VILLANI, O. PEPE, G. MAURIELLO, G. MOSCHETTI, L. SANNINO AND S. COPPOLA. 1996. The behaviour of a four-strains mixture of Listeria monocytogenes (strains Scott A, V7, OH and Cal) during the traditional manufacture of water-buffalo Mozzarella cheese was investigated at two levels of inoculation: ca 105 and 103 cfu ml-1 of vat milk. No significant change in Listeria counts was observed during the curd ripening (4.0–4.5 h), at the end of which the pH ranged between 4.83 and 4.91. A decrease of about 2 log was observed after stretching of the curd in hot water (95°C), followed by complete elimination of Listeria after 48 and 24 h of storage of the final cheese in the conditioning liquid (skim water resulting from the stretching, pH ca 4.0) with initial high and low contamination of the cheese milk respectively. Results also indicated that a 1.7 log reduction of L. monocytogenes could be achieved during the preparation of the natural whey culture utilized as starter in cheesemaking. 相似文献