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991.
The chelate assisted oxidative addition of the H---S bond of L-cysteine esters HSCH2C*H(COOR)NH2 (R = Me, Et), to Pt(PPh3)4 yields the low symmetry cysteine complexes [Pt(H)(SCH2C*H(COOR)NH2)(PPh3)] in one step, with displacement of three moles of triphenylphosphine, only when an excess of the cysteine ester is used. With HSCH2CH2NH2 the excess is not necessary: the 1:1 reaction yields [Pt(H)(SCH2CH2NH2)(PPh3)]. Bulkier HSCH2CH2NMe2 and HSCMe2CH(COOMe)NH2 (penicillamine methyl ester) do not react, even when an excess of ligand is used. 2-Aminothiophenol gives trans-[Pt(H)(SC6H4-2-NH2)(PPh3)2] and does not form a chelate complex. 相似文献
992.
Miguel Lomba Luis Oriol Carlos Sánchez-Somolinos Valeria Grazú María Moros José Luis Serrano Jesús Martínez De la Fuente 《Reactive and Functional Polymers》2013,73(3):499-507
Aliphatic hyperbranched polyesters of different generation, having different nucleophilic groups (such as hydroxyl or sulfonate) in the periphery, have been photocrosslinked by using a trifunctional low molecular weight diazonium salt. The photocrosslinking process, that does not require photoinitiator, allows to prepare polymeric materials that have shown not to cause cytotoxicity when used as substrate for cell growth. Furthermore, cell adhesion studies carried out in polymeric micropatterns generated in glass by direct laser writing, show that cells preferentially proliferate on the structure demonstrating cell affinity for the material. 相似文献
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996.
Teresa D'Amore Aurelia Di Taranto Giovanna Berardi Valeria Vita Giuliana Marchesani Antonio Eugenio Chiaravalle Marco Iammarino 《Comprehensive Reviews in Food Science and Food Safety》2020,19(5):2701-2720
Sulfites are a class of chemical compounds, SO2 releasers, widely used as additives in food industry, due to their antimicrobial, color stabilizing, antibrowning, and antioxidant properties. As the results of these pleiotropic functions they can be added to a broad range of products including dried fruits and vegetables, seafood, juices, alcoholic and nonalcoholic beverage, and in few meat products. Sulfites ingestion has been correlated with several adverse and toxic reactions, such as hypersensitivity, allergic diseases, vitamin deficiency, and may lead to dysbiotic events of gut and oral microbiota. In many countries, these additives are closely regulated and in meat products the legislation restricts their usage. Several studies have been conducted to investigate the sulfites contents in meat and meat products, and many of them have revealed that some meat preparations represent one of the main sources of SO2 exposure, especially in adults and young people. This review discusses properties, technological functions, regulation, and health implications of sulfites in meat‐based foods, and lays a special emphasis on the chemical mechanisms involved in their interactions with organic and inorganic meat components. 相似文献
997.
Giuseppe Venturella Valeria Ferraro Fortunato Cirlincione Maria Letizia Gargano 《International journal of molecular sciences》2021,22(2)
Medicinal mushrooms have important health benefits and exhibit a broad spectrum of pharmacological activities, including antiallergic, antibacterial, antifungal, anti-inflammatory, antioxidative, antiviral, cytotoxic, immunomodulating, antidepressive, antihyperlipidemic, antidiabetic, digestive, hepatoprotective, neuroprotective, nephroprotective, osteoprotective, and hypotensive activities. The growing interest in mycotherapy requires a strong commitment from the scientific community to expand clinical trials and to propose supplements of safe origin and genetic purity. Bioactive compounds of selected medicinal mushrooms and their effects and mechanisms in in vitro and in vivo clinical studies are reported in this review. Besides, we analyzed the therapeutic use and pharmacological activities of mushrooms. 相似文献
998.
Miguel Ángel Silva Salas Jaime Mondragón-Ancelmo María del Rosario Jiménez Badillo Gabriela Rodríguez Licea Fabio Napolitano 《Journal of dairy science》2021,104(5):6175-6184
We aimed to verify whether a low number of relevant animal-based indicators was able to discriminate 33 semi-intensive (grazing during the day and confinement during the night with access to an outdoor paddock; S-INT) and 8 intensive farms (permanent confinement with access to an outdoor paddock; INT) located in the Mexican semi-desert. In addition, we implemented the resource-based assessment scheme Animal Needs Index (ANI) with the identified animal-based indicators to compare the overall level of welfare in INT and S-INT. In particular, we used a protocol made up of 2 parts. The first comprised 4 evaluation sheets (locomotion, flooring, environment, management) and resource-based indicators derived from ANI, and the second one comprised a set of validated animal-based measures focusing on physical conditions and clinical signs of disease derived from the Animal Welfare Indicators scheme and reported in 2 additional sheets. The scoring system was also derived from ANI, with partial scores for each sheet to be summed to obtain the total score. A total of 1,116 dairy goats were assessed. All the observations and recordings were performed by an expert veterinarian evaluator assisted by an auxiliary, and longevity was retrieved from the farm records. The prevalence of animals displaying dirtiness, ocular discharge, abscesses, and claw overgrowth were higher in INT than in S-INT. Disbudding was routinely performed in INT only. Therefore, scurs, indicating improper disbudding, were recorded only in INT. In addition, the longevity of goats raised in S-INT was higher than in INT. Conversely, the prevalence of goats affected by anemia (i.e., FAMACHA scores >2) or lean (i.e., body condition score <2) tended to be higher in S-INT than in INT. No significant differences between the 2 groups of farms were detected for wounds, nasal discharge, integument alterations, fecal soiling, uterine prolapse, and subclinical mastitis. The results obtained using only animal-based measures were confirmed when resource-based variables were also included in the assessment, as 3 out of 6 sheets of the evaluation scheme (i.e., flooring, environment, and health—physical conditions) were scored higher in the S-INT than in the INT. As a consequence, the total score was also higher for S-INT than for INT. We conclude that the selected set of validated animal-based measures was able to discriminate between farms from different production systems. In particular, higher welfare levels were observed in S-INT farms, where the animals were allowed to spend most of the day on natural pasture, compared with INT farms, where the animals were constantly confined. Nevertheless, a certain degree of improvement should also be promoted in terms of anemia and body condition in S-INT farms. 相似文献
999.
Giorgia Ghiara Paolo Piccardo Valeria Bongiorno Luca Repetto Christian Geipel Roberto Spotorno 《International Journal of Hydrogen Energy》2021,46(46):23815-23827
The performance of an SOFC stack is related to the evolution over time of the materials during operation. Metallic interconnects (MICs) are exposed to high temperature (ca. 850 °C) and dual atmosphere (fuel and air streams), and hence react to form an oxide scale on top. This paper focuses on the fuel side of the MIC and investigates the nature of the oxides formed in SOFC stacks field operated by the SUNFIRE GmbH Company for up to 20,000 h in the frame of the EU-H2020 ADASTRA project. This opportunity supports the understanding on how the metal (i.e., CROFER®22APU) reacts once exposed to the fuel stream by performing investigations on the surface and on the cross-section of the samples by SEM-EDS and micro-Raman spectroscopy. The results show the presence of a layered thermally grown oxide (TGO) rich in Cr at the interface with the metal. On top of the scale, a predominant presence of MnxOy is found supporting the hypothesis of a further reaction of the TGO with selective Cr depletion. The manganese oxides may represent a severe issue due to their very low conductivity. 相似文献
1000.