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排序方式: 共有439条查询结果,搜索用时 218 毫秒
81.
M. Pilar Gómez-Serranillos Sara Martín Teresa Ortega Olga M. Palomino Marín Prodanov Visitación Vacas Teresa Hernández Isabel Estrella M. Emilia Carretero 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(4):238-243
Phenolic composition of wine depends not only on the grape variety from which it is made, but on some external factors such
as winemaking technology. Red wine possesses the most antioxidant effect because of its high polyphenolic content. The aim
of this work is to study for the first time, the neuroprotective activity of four monovarietal Spanish red wines (Merlot (ME),
Tempranillo (T), Garnacha (G) and Cabernet-Sauvignon (CS)) through its antioxidant ability, and to relate this neuroprotection
to its polyphenolic composition, if possible. The wine effect on neuroprotection was studied through its effect as free radical
scavenger against FeSO4, H2O2 and FeSO4 + H2O2. Effect on cell survival was determined by 3(4,5-dimethyltiazol-2-il)-2,5-diphenyltetrazolium reduction assay (MTT) and lactate
dehydrogenase (LDH) release assay on astrocytes cultures. Results showed that most of the studied wine varieties induced neuroprotection
through their antioxidant ability in astrocytes, Merlot being the most active; this variety is especially rich in phenolic
compounds, mainly catechins and oligomeric proanthocyanidins. Our results show that red wine exerts a protection against oxidative
stress generated by different toxic agents and that the observed neuroprotective activity is related to their polyphenolic
content. 相似文献
82.
83.
Shuxian Li Anatoliy Lygin Olga Zernova Vera Lozovaya Glen L.Hartman Jack M.Widholm 《大豆科学》2008,27(2):275-282
摘要:茄病镰刀菌(Fusarium solani f.sp.glydne)是一种土生细菌,通过侵染大豆根系引发猝死综合症。利用温室盆栽试验和须根培养试验研究了接种茄孢镰刀菌对13个不同基因型大豆的影响。结果表明:接种后所有盆栽大豆主根都有明显深褐色的侵染病斑;移植后21d测定了盆栽植株叶部发病程度,Peking表现最为严重,然后依次为Spencer,Ripley,P3981,Williams82,Essex,Forrest,Iroquois,PI520733,Hartwig,PI567650B,Jack,和PI567374。叶部发病程度与冠高(r=-0.422,P=0.0018)、冠重(r=-0.857,P〈0.0001)和根重(r=-0.732,P〈0.0001)呈显著负相关。主根病斑长度与叶部发病程度没有相关性,表明大豆对病原菌的抗性不能仅通过根系得到充分控制。对培养的大豆须根接种茄病镰刀菌菌丝体10d后,不同基因型大豆的菌落直径的变化范围为17—40mm,差异显著(P=0.05),其中Spencer和Peking须根上的菌落直径显著(P=0.05)大于PI567374和PI520733。对Spencer和PI567374的须根接种10灿茄病镰刀菌常量成分悬浮液,10d后菌落直径分别为50和38mm,差异显著(P=0.05)。通常,不同基因型大豆间茄病镰刀菌在培养须根上的生长与整株的症状间有一定的相关性,但不总是这样,这是因为即使根系对毒素产生抗性来减少叶部病害症状,但并不是所有的大豆都表现出明显的根系抗性。 相似文献
84.
Matías Santini Elsa Lucila Camadro Olga Noemí Marcellán Luis Ernesto Erazzú 《American Journal of Potato Research》2000,77(4):211-218
Five diploid hybrid families derived from crosses between haploids of three Argentinian cultivars and three diploid wild species,Solanum gourlayi, S. chacoense andS. spegazzinii, were evaluated in a field experiment in Balcarce. All plants were androsterile and, thus, could not be screened for 2n pollen production. Data on agronomic tuber traits were statistically analyzed. Differences among families were non-significant for tuber number/plant, but were significant for tuber weight/plant and dry matter content (with values above 21.0% in two of them). The relative frequencies of tubers in the categories established for size, skin texture, and eye depth were family dependent, but they were familiy independent in the categories established for tuber shape and skin color. Great morphological variability was detected for all the traits studied, and plants with high yield and high dry matter content were identified. These families can be used as sources of germplasm in breeding and to explore heterotic responses in 2x × 4x crosses, given the capacity of some plants to produce 2n eggs, as found in a related investigation. 相似文献
85.
对小麦品系Saratovskaya29的不同Rht等位的一套近等基因系进行了田间试验,以测定6个矮杆基因的育种值。在不灌溉、灌溉并施用不同剂量的肥料(N120,P100,K60和N180,P160,K100)三种条件下测定Rht基因对株高、产量及产量构成因子、品质的影响。结果表明,Rht基因可以用于伏尔加河地区条件下魏杆小麦品系的选育。 相似文献
86.
Natalia V. Krylova Anna O. Kravchenko Olga V. Iunikhina Anastasia B. Pott Galina N. Likhatskaya Aleksandra V. Volodko Tatyana S. Zaporozhets Mikhail Y. Shchelkanov Irina M. Yermak 《Marine drugs》2022,20(1)
The structural diversity and unique physicochemical properties of sulphated polysaccharides of red algae carrageenans (CRGs), to a great extent, determine the wide range of their antiviral properties. This work aimed to compare the antiviral activities of different structural types of CRGs: against herpes simplex virus type 1 (HSV-1) and enterovirus (ECHO-1). We found that CRGs significantly increased the resistance of Vero cells to virus infection (preventive effect), directly affected virus particles (virucidal effect), inhibited the attachment and penetration of virus to cells, and were more effective against HSV-1. CRG1 showed the highest virucidal effect on HSV-1 particles with a selective index (SI) of 100. CRG2 exhibited the highest antiviral activity by inhibiting HSV-1 and ECHO-1 plaque formation, with a SI of 110 and 59, respectively, when it was added before virus infection. CRG2 also significantly reduced the attachment of HSV-1 and ECHO-1 to cells compared to other CRGs. It was shown by molecular docking that tetrasaccharides—CRGs are able to bind with the HSV-1 surface glycoprotein, gD, to prevent virus–cell interactions. The revealed differences in the effect of CRGs on different stages of the lifecycle of the viruses are apparently related to the structural features of the investigated compounds. 相似文献
87.
Elena V. Girich Anton N. Yurchenko Olga F. Smetanina Phan Thi Hoai Trinh Ngo Thi Duy Ngoc Mikhail V. Pivkin Roman S. Popov Evgeny A. Pislyagin Ekaterina S. Menchinskaya Ekaterina A. Chingizova Shamil S. Afiyatullov Ekaterina A. Yurchenko 《Marine drugs》2020,18(12)
Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity. 相似文献
88.
Olga Hering 《Journal of pest science》1926,2(2):13-15
Ohne Zusammenfassung
Mit 7 Abbildungen 相似文献
89.
Luke A. J. Haydock Anthony C. G. Abrams-Ogg J. Scott Weese Michael R. Goldstein Amy B. Clifford Adrian Sebastian Elizabeth H. Rea Frances B. Jamieson Carla Duncan Olga Andrievskaia Mirjana Savic Durda Slavic Robert A. Foster Christopher J. Greenwood Tamara L. MacDonald Jacqueline E. Scott Andrea Sanchez 《Journal of veterinary diagnostic investigation》2022,34(2):292
A 4-y-old, female mixed-breed dog was presented to the Ontario Veterinary College for further evaluation of multiple pulmonary and hepatic masses, intrathoracic lymphadenitis, and recent development of a pyogranulomatous pleural effusion. Along with other comprehensive tests, a thoracic lymph node biopsy was performed, and Mycobacterium tuberculosis complex infection was confirmed by real-time PCR. The dog’s condition declined post-operatively, and euthanasia was elected. Postmortem examination confirmed severe granulomatous pneumonia, hepatitis, intrathoracic and intraabdominal lymphadenitis, omentitis, and nephritis. Line-probe assays performed on samples collected postmortem confirmed the species as M. tuberculosis. 24-loci MIRU-VNTR genotyping, spoligotyping, and whole-genome sequencing revealed relations to known human isolates, but no epidemiologic link to these cases was investigated. Given the concern for potential human exposure during this animal’s disease course, a public health investigation was initiated; 45 individuals were tested for M. tuberculosis exposure, and no subsequent human infections related to this animal were identified. Our case highlights the need for more readily available, minimally invasive testing for the diagnosis of canine mycobacteriosis, and highlights the ability of canid species to act as potential contributors to the epidemiology of M. tuberculosis infections. 相似文献
90.