排序方式: 共有92条查询结果,搜索用时 31 毫秒
21.
First report of Cucurbit aphid-borne yellows virus in Italy 总被引:2,自引:0,他引:2
22.
23.
Maria Grazia PALMERINI Monica ANTINORI Marta MAIONE Fabrizio CERUSICO Caterina VERSACI Stefania Annarita NOTTOLA Guido MACCHIARELLI Mohammad Ali KHALILI Severino ANTINORI 《The Journal of reproduction and development》2014,60(6):411-420
In vitro maturation of vitrified immature germinal vesicle (GV) oocytes is a promising fertility preservation option. We analyzed the ultrastructure of human GV oocytes after Cryotop vitrification (GVv) and compared it with fresh GV (GVc), fresh mature metaphase II (MIIc) and Cryotop-vitrified mature (MIIv) oocytes. By phase contrast microscopy and light microscopy, the oolemmal and cytoplasmic organization of fresh and vitrified oocytes did not show significant changes. GVv oocytes showed significant ultrastructural alterations of the microvilli in 40% of the samples; small vacuoles and occasional large/isolated vacuoles were abnormally present in the ooplasm periphery of 50% of samples. The ultrastructure of nuclei and mitochondria-vesicle (MV) complexes, as well as the distribution and characteristics of cortical granules (CGs), were comparable with those of GVc oocytes. MIIv oocytes showed an abnormal ultrastructure of microvilli in 30% of the
samples and isolated large vacuoles in 70% of the samples. MV complexes were normal, but mitochondria-smooth endoplasmic reticulum aggregates appeared to be of reduced size. CGs were normally located under the oolemma but presented abnormalities in distribution and matrix electron density. In conclusion, Cryotop vitrification preserved main oocyte characteristics in the GV and MII stages, even if peculiar ultrastructural alterations appeared in both stages. This study also showed that the GV stage appears more suitable for vitrification than the MII stage, as indicated by the good ultrastructural preservation of important structures that are present only in immature oocytes, like the nucleus and migrating CGs. 相似文献
24.
25.
Manna C Migliardi V Sannino F De Martino A Capasso R 《Journal of agricultural and food chemistry》2005,53(24):9602-9607
Chemically stable di- and triacetyl derivatives of the natural o-diphenol antioxidant hydroxytyrosol were synthesized, and their chemical and biological antioxidant activities were assessed in comparison with that of the native synthetic compound. The chemical antioxidant activity of the selected compounds was evaluated by measuring the ferric reducing antioxidant power (FRAP). The data clearly indicate that, as expected, the hydroxytyrosol analogues, modified in the o-diphenolic ring, are devoid of any chemical antioxidant activity. On the contrary, both acetyl derivatives, at micromolar concentrations, equally protect against tert-butylhydroperoxide-induced oxidative damages in Caco-2 cells and human erythrocytes. This paper for the first time reports that chemically stable hydroxytyrosol acetyl derivatives, although devoid of chemical antioxidant activity, are as effective as the parent compound in protecting human cells from oxidative stress-induced cytotoxicity, after metabolization by esterases at the intestinal level, suggesting their possible utilization in either nutritional (functional food), cosmetic, or pharmaceutical preparations. 相似文献
26.
Mattoli L Cangi F Maidecchi A Ghiara C Tubaro M Traldi P 《Journal of agricultural and food chemistry》2005,53(26):9860-9866
Immature bitter orange fruit and its extracts have been introduced into the market as an alternative to Ephedra in weight loss products. However, the safety of the immature bitter orange fruit and its extracts is a debated argument due to the presence of synephrine, a constituent known as a sympathomimetic agent. In this paper, we describe the development of a new, rapid, and simple liquid chromatography-electrospray ionization-tandem mass spectrometry method devoted to the quantitative determination of synephrine in bitter orange samples, containing a high quantity of synephrine, and sweet orange samples, known to contain a low level of synephrine but at the same time being one of the main synephrine sources in a normal human diet. Two bitter orange dry extracts containing 5 and 6% sSynephrine and 10 sweet orange samples have been analyzed. Between the sweet orange samples, six were fresh oranges and four were fresh-squeezed juices; in these samples, the synephrine levels ranged from 0.00128 to 0.00349%. 相似文献
27.
28.
Mohamadi Yalsuyi Ahmad Forouhar Vajargah Mohammad Hajimoradloo Abdolmajid Mohammadi Galangash Mohsen Prokić Marko D. Faggio Caterina 《Veterinary research communications》2022,46(2):389-396
Veterinary Research Communications - Industrial chemical solutions are widely used as a method to disinfection of aquaculture water and environments. The aim of the present study was to evaluate... 相似文献
29.
Ligands involved in Pb immobilization and transport in lettuce,radish, tomato and Italian ryegrass
下载免费PDF全文
![点击此处可从《植物养料与土壤学杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Luisa Massaccesi Carlo Meneghini Tatiana Comaschi Roberto D'Amato Andrea Onofri Daniela Businelli 《植物养料与土壤学杂志》2014,177(5):766-774
Lead (Pb) and other heavy metals represent a great source of concern in agriculture because they may disperse from polluted sources and accumulate in crop organs. This research study was performed with three edible crops and one pasture species (lettuce: Lactuca sativa L. cv. Romana; radish: Raphanus sativus L. var. radicicola; tomato: Lycopersicon lycopersicum L. Karst.; Italian ryegrass: Lolium multiflorum Lam). It was aimed at (1) assessing how species affect Pb distribution among plant organs, (2) determining the extent to which Pb is localized in edible organs, and (3) ascertaining whether it could be possible to distinguish which compounds are responsible for the transport of Pb from one plant organ to another and which compounds are responsible for the accumulation of this metal inside each plant organ. The experiment was conducted in the greenhouse. Plants were grown in plastic pots using a Pb‐spiked sandy soil as substrate. Total Pb concentrations in different plant organs and in soil were determined. Within plants, the maximum accumulation of Pb was found in roots while the remaining part of Pb was mainly located in leaves. Pb LIII edge XANES (X‐ray Absorption Near Edge Spectroscopy) was applied to identify the principal Pb carrier molecules in the different plant organs. The data suggest that in roots Pb immobilization is mainly due to the complexing ability of histidine, which binds the metal and, to a lesser extent, to precipitation of Pb as carbonate. The transport to the upper plant organs is mainly attributed to Pb complexes with organic acids. In stems and leaves, Pb bonding is mainly carboxylic and amino acid‐like, thus confirming the role of these substances in promoting Pb mobility. Thio amino acidic (glutathione and cysteine‐like) Pb complexes, which in this study were only found in stems, can also be held responsible for Pb long‐distance transport from roots to shoots. 相似文献
30.
Protective effect of the phenolic fraction from virgin olive oils against oxidative stress in human cells 总被引:3,自引:0,他引:3
Manna C D'Angelo S Migliardi V Loffredi E Mazzoni O Morrica P Galletti P Zappia V 《Journal of agricultural and food chemistry》2002,50(22):6521-6526
This paper reports the protective effect of the phenolic fraction extracted from extra virgin olive oils (OOPEs) against the cytotoxic effects of reactive oxygen species in human erythrocytes and Caco-2 cells, employed as model systems. Pretreatment of cells with various OOPEs, indeed, provides a remarkable protection against oxidative damages: this effect was strictly dependent on the o-diphenolic content of the extracts. Moreover, the protective effects observable in cellular systems were compared with in vitro antioxidant properties, measured by using the FRAP (ferric reducing/antioxidant power) assay; the reducing ability of OOPEs strictly parallels their o-phenolic content. The linear relationship demonstrated between biological effects and antioxidant capacity measured by the FRAP assay allows us to propose the use of this rapid colorimetric method in assessing and certifying the antioxidant power of extra virgin olive oil. 相似文献