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91.
Procyanidins from Vitis vinifera seeds: in vivo effects on oxidative stress   总被引:3,自引:0,他引:3  
The purpose of this study was to evaluate the effect of supplementation with procyanidins from Vitis vinifera on markers of oxidative stress. Ten healthy volunteers received a daily dose of 110 mg of procyanidins for 30 days. Fasting venous blood samples were taken before and at the end of the supplementation period and after 7 days of wash-out. The total antioxidant activity and the plasma concentrations of alpha-tocopherol were not modified. Conversely, the levels of alpha-tocopherol in red blood cell membranes increased significantly from 1.8 +/- 0.1 to 2.8 +/- 0.2 mg/g. Similarly, the lymphocyte oxidized DNA [8-oxo-7,8-dihydro-2'-deoxyguanosine/2'-deoxyguanosine ratio] was reduced from 7.23 +/- 2.47 to 2.34 +/- 0.51, and the red blood cell membrane fatty acid composition shifted to a higher level of polyunsaturated fatty acids. On the basis of these results, it may be suggested that dietary procyanidins exert their antioxidant protection in vivo by sparing liposoluble vitamin E and reducing DNA oxidative damage.  相似文献   
92.
Diagnosing high intracranial pressure by clinical and diagnostic imaging is particularly challenging for chronic or slow‐growing lesions. The aim of this prospective case‐control study is to determine whether the neuroscore and brain magnetic resonance imaging (MRI) are related to the direct measurement of intracranial pressure in sheep affected by intracranial slow‐growing lesions due to chronic cerebral coenurosis (Coenurus cerebralis). Seventeen affected and 10 control sheep were included. All animals underwent a neurological examination, MRI of the brain, and direct measurement of intracranial pressure. The severity of clinical signs and MRI findings were scored. Data were statistically analyzed. The invasive intracranial pressure value was higher in affected animals. A severely altered neuroscore is related to an increased intracranial pressure beyond the normal threshold (< 0.05). The volume of the calvarium was larger in affected animals than in control animals (P = 0.0001) and was positively influenced by the presence and volume of the parasitic cyst (r = 0.7881, P < 0.01). Several degrees of deviation and deformation of both the ventricular system and brain parenchyma were detected by MRI. Subjective MRI findings were not associated with intracranial hypertension. In conclusion, this study shows that in sheep affected by slow‐growing lesions, severe alterations in the neuroscore and the results of objective MRI are related to an increased intracranial pressure beyond the normal threshold.  相似文献   
93.
Citrus tristeza virus (CTV) is the causal agent of the most important virus disease of citrus. Numerous CTV isolates differing in biological and molecular characteristics have been reported worldwide. Recently, CTV was detected in Italy in several citrus crops from three separate areas: (1) Cassibile, province of Syracuse; (2) Massafra, province of Taranto; and (3) Belpasso, province of Catania. CTV isolates from Massafra and Cassibile were mild, whereas isolates from Belpasso induced severe symptoms. To study the genetic variation of CTV populations of these areas, 150 samples per area were examined by single strand conformation polymorphism (SSCP) and nucleotide sequence analysis of CTV gene p20. All isolates from the same area showed the same SSCP pattern whereas for each area a different SSCP pattern was obtained. The Massafra and the Cassibile isolates had a nucleotide identity higher than 99% with a mild isolate from Spain and about 92% with the Belpasso isolates, which were similar (identity higher than 99%) to severe isolates from California and Japan. These results suggest at least two independent introductions of CTV in Italy, probably by import of CTV-infected budwoods. Within each area, the virus population was homogeneous suggesting diffusion of CTV by aphid transmission. The GenBank accession numbers of the sequences reported in this paper are: AY262000, AY263360 and AY263361 corresponding to gene p20 of CTV isolates from Massafra, Cassibile and Belpasso (Italy), respectively.  相似文献   
94.
95.
In an attempt to standardise the determination of biological reference values, the International Federation of Clinical Chemistry (IFCC) has published a series of recommendations on developing reference intervals. The IFCC recommends the use of an a priori sampling of at least 120 healthy individuals. However, such a high number of samples and laboratory analysis is expensive, time-consuming and not always feasible, especially in veterinary medicine. In this paper, an alternative (a posteriori) method is described and is used to determine reference intervals for biochemical parameters of farm animals using an existing laboratory data set. The method used was based on the detection and removal of outliers to obtain a large sample of animals likely to be healthy from the existing data set. This allowed the estimation of reliable reference intervals for biochemical parameters in Sarda dairy sheep. This method may also be useful for the determination of reference intervals for different species, ages and gender.  相似文献   
96.
Molecular weight and size distributions of two glutenin polymers were determined by a multi-angle laser light scattering (MALLS) photometer on-line to a size exclusion chromatography (SEC) system. Two glutenin polymers extracted, sonicated and purified from wheat flours of different cultivars, i.e. Cheyenne and Chinese Spring, were accurately fractionated by SEC using three buffers (pH 2.6, 4.0 and 6.9) and two column sets. Both molecular weight distribution (MWD) and radius of gyration distribution (RGD) could be used to differentiate the two cultivars. MWD of glutenin polymers is a complex mixture of high- and low-molecular weight fractions and the relative percentage was found to be very different. The two cultivars were found to be different; in particular, the Chinese Spring polymer showed more compact conformation than the Cheyenne polymer. The slope of the conformation plot for glutenin was about 0.37, close to the theoretical value for compact spheres. Determination of glutenin MWD and RGD was difficult and depended on the buffer used and the SEC columns.  相似文献   
97.
The effect of alkaline lignin (AL) and sodium lignosulfonate (LSS) on the structure of thermoplastic zein (TPZ) was studied. Protein structural changes and the nature of the physical interaction between lignin and zein were investigated by means of X-ray diffraction and Fourier transform infrared (FT-IR) spectroscopy and correlated with physical properties. Most relevant protein structural changes were observed at low AL concentration, where strong H-bondings between the functional groups of AL and the amino acids in zein induced a destructuring of inter- and intramolecular interactions in α-helix, β-sheet, and β-turn secondary structures. This destructuring allowed for an extensive protein conformational modification which, in turn, resulted in a strong improvement of the physical properties of the bionanocomposite.  相似文献   
98.
Nonspecific lipid-transfer proteins (nsLTPs) have been recognized as allergens in several plant species among which are cereals important in human nutrition. In this report, we purified a 9600 +/- 1 Da protein from both soft wheat and farro bran. Mass spectrometric analyses revealed that these proteins are identical, belong to the nsLTP1 class, and have high sequence homology with nsLTP1 isolated from other cereal species. Their identification was further supported by the ability of the soft wheat nsLTP1 to transfer pyrene-labeled lipids between donor and acceptor membranes. The results are discussed in view of the increasing diffusion on the markets of bran-rich products.  相似文献   
99.
Summary Exploration and collection of plant genetic resources were continued in central Italy 1989—regions Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon was used as an indicator for traditional agriculture. 169 accessions were collected, mainly of cereals, vegetables and grain legumes. Worth mentioning are land-races ofTriticum aestivum, T. durum, Secale cereale, Pisum sativum, Lactuca sativa andCucurbita maxima. Brassica oleracea var.palmifolia, the palm-leaved kale, is an important vegetable in the Toscana. Several other rare crops could be also collected.
Sammlung pflanzlicher genetischer Ressourcen in Italien 1989
Zusammenfassung Die Exploration und Sammlung pflanzlicher genetischer Ressourcen wurden 1989 in Mittelitalien fortgesetzt — Regionen Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon wurde als Indikator für traditionelle Landwirtschaft verwendet. 169 Proben wurden gesammelt, hauptsächlich von Getreiden, Gemüsen und Körnerleguminosen. Erwähnenswert sind Landsorten vonTriticum aestivum, T. durum, Secale cereale, Pisum sativum undCucurbita maxima. Brassica oleracea var.palmifolia, der Palmkohl, ist ein wichtiges Gemüse in der Toscana. Verschiedene andere seltene Fruchtarten konnten ebenfalls gesammelt werden.

1989
1989 , , , .Triticum dicoccon . 169 , , . Triticum aestivum, T. durum, Secale cereale, Pisum sativum Cucurbita maxima. Brassica oleracea var.palmifolia, , . .
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100.
We investigated the taxonomic position and symbiotic capabilities of two root-nodule bacterial strains isolated from the South African herbaceous, papilionoid legume Rhynchosia ferulifolia. The 16S rRNA gene sequence of the two strains was determined along with intragenic sequences of nodA and nifH, together with their symbiotic capabilities when inoculated onto the papilionoid legumes R. ferulifolia, Rhynchosia caribaea, Rhynchosia minima and Macroptilium atropurpureum (Siratro). Burkholderia phymatum STM815T, Cupriavidus taiwanensis LMG 19424T and root-nodule bacteria isolated from R. minima and Rhynchosia totta were included in the study. Root-nodule bacteria isolated from R. ferulifolia, WSM3937 and WSM3930, belong to the genus Burkholderia and are most closely related to Burkholderia terricola (98.8% similarity). The phylogenetic analysis of nodA and nifH revealed substantial similarity of the novel strains with Burkholderia tuberum STM678T, a β-rhizobium also originated from South Africa, and only a distant relationship with South American Mimosa-nodulating β-rhizobia. R. ferulifolia was effectively nodulated only by Burkholderia sp. WSM3937 and WSM3930 and not by bradyrhizobia isolated from Rhynchosia minima and Rhynchosia totta or STM815 and LMG 19924. Nodules induced by the novel strains were determinate and hosted well organized symbiosomes within infected cells. In this study we describe a new symbiotic N-fixing relationship between Burkholderia sp. and the South African legume R. ferulifolia. This is the first report of N-fixation between β-rhizobia and an herbaceous, papilionoid legume from which the strains were originally isolated. The level of N-fixation in this symbiosis approached that achieved by effectively nodulated Medicago sativa and suggests that the β-rhizobia may have a role in N-fixation in agricultural systems.  相似文献   
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