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排序方式: 共有270条查询结果,搜索用时 15 毫秒
1.
Antioxidant effect of diethyldithiocarbamate on microsomal lipid peroxidation assessed by low-level chemiluminescence and alkane production 总被引:3,自引:0,他引:3
Different thiol-containing compounds, such as diethyldithiocarbamate (DDC), glutathione, penicillamine, and dithioerythritol have been chosen to study their effect on ascorbate/Fe-ADP-induced lipid peroxidation, detected by low-level chemiluminescence and alkane production. In the concentration range used, these thiols exerted a temporary protection against lipid peroxidation by lengthening the induction period; after overcoming this induction period, no substantial inhibition of either chemiluminescence or alkane production was observed. DDC was effective in protecting against lipid peroxidation in the nanomolar range, whereas the group of other thiol-containing molecules operated in the millimolar range. 相似文献
2.
F Bartoli G Paradies D Virgintino A Leggio L Roncali 《Bollettino della Società italiana di biologia sperimentale》1990,66(2):181-188
The ureter structure was analyzed under light microscope on serial sections in newborn children affected by obstruction of the pyelo-ureteric junction. In the obstructive segments, preceded by ureter portions dilated and provided with close-packed layers of smooth muscle layers, the tunica mucosa was lacking epithelial cover, its lamina propria was thickened, being built by conspicuous bundles of collagen fibers, and the tunica muscularis showed scarce and disrupted groups of muscle cells invaded by connective tissue. Numerous mastocytes were seen in the mucosa and muscularis tunicae. The results suggest that the breaking of the epithelium may be a primary pathogenetic event followed by passage of urine in the subjacent tissues in turn responsible for a diffuse connective reaction, and, therefore for a final fibrosis of the ureter wall. The role of the mastocytes in the etiopathogenesis of the pyelo-ureteric junction obstruction was also discussed. 相似文献
3.
The genusLepidauchen is discussed and defined. It is removed from the family Lepocreadiidae and placed in the family Acanthocolpidae based mainly on its possession of a uterine seminal receptacle. The type, and only valid species,L. stenostoma, is redescribed using material fromLabrus merula from Corsica. Material fromCoris julis andSymphodus tinca from the western Mediterranean off Marseille,L. merula from the western Mediterranean off Valencia,Diplodus annularis andLithognathus mormyrus from the Adriatic Sea off Montenegro, andArchosargus unimaculatus from Venezuela was also examined. Other nominal species are discussed, but none are considered valid within this genus. 相似文献
4.
Three species of cryptogonimid digeneans are redescribed from the gut of Sciaena umbra off Corsica. The systematics of the three species, Metadena pauli (Vlassenko, 1931), Paracryptogonimus aloysiae (Stossich, 1885) n. comb. and Anoiktostoma coronatum (Wagener, 1852), are discussed. The latter two species, which have not been reported for more than 100 years, have previously been confused and synonymised with each other. P. aloysiae, which is transferred to Paracryptogonimus from Anoiktostoma, is restricted to the rectum, whereas A. coronatum prefers the pyloric caeca and anterior intestine. 相似文献
5.
G Palka P Santi A D'Antuono S Bartoli G Mazzotti N M Maraldi F A Manzoli 《Bollettino della Società italiana di biologia sperimentale》1981,57(1):33-39
We report cytogenetic data concerning 9 patients with chronica granulocytic leukemia and eosinophilia at the onset and during the chronic phase of the disease before the blastic crisis. The cariotype analises in the intermediate phases allowed to determine the first changes which could be involved in the evolutionary events of the disease up to the moment in which the typical markers of the blastic crisis can be found. 相似文献
6.
S. Papa A. Pellegrino G. Bartoli R. Ruosi S. Rianna A. Fuggi 《Plant biosystems》2013,147(6):1187-1198
The aim of this study was to analyse the amount and qualitative characteristics of organic matter (OM) in the litter horizon (considering leaf litter at different decomposition stages) and underlying soil to a 30-cm depth in a beech stand on the Apennines in southern Italy. Distribution of major nutrients as well as fungal and microbial biomass were also evaluated, in addition to beech leaf nutrient content monitor from full expansion to abscission in order to estimate annual nutrient input to soil from litterfall and nutrient retranslocation before abscission. OM was significantly higher in leaf litter. C/N ratio and the Na, Mn, Fe levels also decreased along the decomposition continuum, whereas N and S contents slowly decreased with soil depth. Generally, leaf nutrient content was also significantly lower in dead leaves, indicating efficient retranslocation to persistent organs. Fungal biomass was the highest in leaf layers, with no significant changes between spring and autumn samplings. Enzyme activities did not differ significantly along the decomposition continuum but marked decreases were found in the upper soil layer; these remained relatively constant, with the exception of laccase, at deeper soil depths. No seasonal effect on enzyme activities and OM content was found. 相似文献
7.
Colonization of Wheat Roots by an Exopolysaccharide-Producing Pantoea agglomerans Strain and Its Effect on Rhizosphere Soil Aggregation 总被引:2,自引:0,他引:2 下载免费PDF全文
The effect of bacterial secretion of an exopolysaccharide (EPS) on rhizosphere soil physical properties was investigated by inoculating strain NAS206, which was isolated from the rhizosphere of wheat (Triticum durum L.) growing in a Moroccan vertisol and was identified as Pantoea aglomerans. Phenotypic identification of this strain with the Biotype-100 system was confirmed by amplified ribosomal DNA restriction analysis. After inoculation of wheat seedlings with strain NAS206, colonization increased at the rhizoplane and in root-adhering soil (RAS) but not in bulk soil. Colonization further increased under relatively dry conditions (20% soil water content; matric potential, −0.55 MPa). By means of genetic fingerprinting using enterobacterial repetitive intergenic consensus PCR, we were able to verify that colonies counted as strain NAS206 on agar plates descended from inoculated strain NAS206. The intense colonization of the wheat rhizosphere by these EPS-producing bacteria was associated with significant soil aggregation, as shown by increased ratios of RAS dry mass to root tissue (RT) dry mass (RAS/RT) and the improved water stability of adhering soil aggregates. The maximum effect of strain NAS206 on both the RAS/RT ratio and aggregate stability was measured at 24% average soil water content (matric potential, −0.20 MPa). Inoculated strain NAS206 improved RAS macroporosity (pore diameter, 10 to 30 μm) compared to the noninoculated control, particularly when the soil was nearly water saturated (matric potential, −0.05 MPa). Our results suggest that P. agglomerans NAS206 can play an important role in the regulation of the water content (excess or deficit) of the rhizosphere of wheat by improving soil aggregation. 相似文献
8.
9.
Drought and watering-dependent oxidative stress: effect on antioxidant content in Triticum aestivum L. leaves 总被引:3,自引:0,他引:3
Bartoli G; Simontacchi M; Tambussi E; Beltrano J; Montaldi E; Puntarulo S 《Journal of experimental botany》1999,50(332):373-381
The purpose of the present work was to evaluate both oxidative stress and
the antioxidant response system in leaves from wheat (Triticum
aestivum cv. Buck Poncho) subjected sequentially to drought and
watering. Drought was imposed by withholding water until soil water
potential reached -2.0 MPa and maintained under those conditions for 24 h.
DCFDA oxidation by wheat leaves was not significantly affected by drought,
but watering led to an approximately 2-fold increase in DCFDA oxidation
rate. However, no significant effect either on lipid radical content or on
hydroperoxide content was measured after drought and drought followed by
watering. Microsomes isolated from leaves exposed to drought, and from
leaves exposed to drought followed by watering, generated a significantly
higher amount of hydroxyl radical as compared to microsomes isolated for
control leaves suggesting a higher production of hydroxyl radical in the
cellular water soluble phase, after drought and watering as compared to
control values. The content of -tocopherol
in wheat leaves was increased 2.4-fold after drought and -carotene content was increased by 2.6-fold after
drought. Hydration lowered lipid-soluble antioxidant content to control
values. Total thiol content as increased by 70% after drought, and watering
did not significantly alter the enhanced values. Drought decreased by 28.5%
the content of reduced ascorbic acid. Taken as a whole, active species
formed at wheat membranes after exposure to moderate water stress, are
efficiently removed upon rehydration by reaction with an increased content
of -tocopherol and -carotene. Moreover a co-ordinated response
involving glutathione reductase activity, thiols and ascorbic acid is
triggered to limit free radical dependent effects.Key
words: Antioxidants, lipid radicals, oxygen radicals, water
stress, wheat
相似文献
10.