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排序方式: 共有504条查询结果,搜索用时 15 毫秒
51.
A Osterhaus M van de Bildt L Vedder B Martina H Niesters J Vos H van Egmond D Liem R Baumann E Androukaki S Kotomatas A Komnenou B Abou Sidi AB Jiddou ME Barham 《Canadian Metallurgical Quarterly》1998,16(9-10):979-981
During the past few months, more than half of the total population of about 300 highly endangered Mediterranean monk seals (Monachus monachus) on the western Saharan coast of Africa, died in a mysterious disease outbreak. Epizootiological and postmortem findings were reminiscent of similar outbreaks amongst pinniped and cetacean species in recent years, which were caused by an infection with newly discovered morbilliviruses (for review see osterhaus et al.). Virological, as well as toxicological, analysis performed on tissue samples collected from relatively fresh carcasses during the outbreak indicate that infection with a virus closely related to dolphin morbillivirus (DMV), possibly originating from affected dolphins in the same area, was the primary cause of the outbreak. Therefore it is concluded that vaccination with a safe and effective non-replicating vaccine should be considered as a management tool in the conservation of Mediterranean monk seals. 相似文献
52.
W. M. Abou El-ella S. M. Farahat A. H. Guirguis A. M. El-fak A. A. El-Neshawy 《Molecular nutrition & food research》1978,22(5):471-475
Ras cheese was manufactured using a starter culture grown on soy milk medium. Resultant cheese was compared with that resulted by using the ordinary starter culture grown on skim milk medium. The use of the former starter resulted in increasing cheese acidity, total volatile fatty acids, formol and SCHILOVICH ripening indices throughout the ripening period. Also higher total bacterial number and lactic acid bacterial number were observed. 相似文献
53.
Gamal R. Saad Rania E. Morsi Sayed Z. Mohammady Maher Z. Elsabee 《Journal of Polymer Research》2008,15(2):115-123
A series of alkyl-grafted copolymers based on styrene-maleic anhydride (SMA) copolymers were synthesized by esterification
of SMA with several long chain normal aliphatic alcohols. The prepared copolymers were characterized by FT-IR and 1H NMR and DSC. The dielectric behavior of these copolymers was investigated in the frequency 20–105 Hz and temperature −40 to 180 °C ranges. Two relaxation processes were observed, α, and β-relaxation. The former is associated
with the glass-rubber transition and is characterized by the Vogel–Fulcher–Tammann temperature dependence and the latter relaxation
is related to the local motion of the ester side groups attached to the polymer backbone. The apparent activation energy for
the β-relaxation was found to depend significantly on the alkyl chain length. The dielectric analysis of the β-relaxation
process detected is discussed. 相似文献
54.
55.
X-ray diffraction techniques have been applied to study the structural changes and processes which take place when zinc metal is subjected to oxidation and self-polarization at the metal-electrolyte interface. The effect of electrolyte concentration and anodizing voltage on the structure and composition of the ZnO layer formed was investigated. 相似文献
56.
Abou Bakr M. Salama Ahmad Gebreil Tamer M. A. Mohamed Riham R. E. Abouleisa 《International journal of molecular sciences》2021,22(14)
Unlike some lower vertebrates which can completely regenerate their heart, the human heart is a terminally differentiated organ. Cardiomyocytes lost during cardiac injury and heart failure cannot be replaced due to their limited proliferative capacity. Therefore, cardiac injury generally leads to progressive failure. Here, we summarize the latest progress in research on methods to induce cardiomyocyte cell cycle entry and heart repair through the alteration of cardiomyocyte plasticity, which is emerging as an effective strategy to compensate for the loss of functional cardiomyocytes and improve the impaired heart functions. 相似文献
57.
Sabeel P. Valappil Derren Ready Ensanya A. Abou Neel David M. Pickup Wojciech Chrzanowski Luke A. O'Dell Robert J. Newport Mark E. Smith Michael Wilson Jonathan C. Knowles 《Advanced functional materials》2008,18(5):732-741
Novel quaternary gallium‐doped phosphate‐based glasses (1, 3, and 5 mol % Ga2O3) were synthesized using a conventional melt quenching technique. The bactericidal activities of the glasses were tested against both Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) and Gram‐positive (Staphylococcus aureus, methicillin‐resistant Staphylococcus aureus, and Clostridium difficile) bacteria. Results of the solubility and ion release studies showed that these glass systems are unique for controlled delivery of Ga3+. 71Ga NMR measurements showed that the gallium is mostly octahedrally coordinated by oxygen atoms, whilst FTIR spectroscopy provided evidence for the presence of a small proportion of tetrahedral gallium in the samples with the highest gallium content. FTIR and Raman spectra also afford an insight into the correlation between the structure and the observed dissolution behavior via an understanding of the atomic‐scale network bonding characteristics. The results confirmed that the net bactericidal effect was due to Ga3+, and a concentration as low as 1 mol % Ga2O3 was sufficient to mount a potent antibacterial effect. The dearth of new antibiotics in development makes Ga3+ a potentially promising new therapeutic agent for pathogenic bacteria including MRSA and C. difficile. 相似文献
58.
Rania Mhiri Mona Kchaou Sahla Belhadj Abdelfattah El Feki Noureddine Allouche 《Sensing and Instrumentation for Food Quality and Safety》2018,12(2):839-847
The aromatic compounds and biological activities of essential oils from six Tunisian aromatic plants including Artemisia herba-alba, Rosmarinus officinalis, Thymus capitatus, Mentha piperita, Ocimum basilicum and Artemisia absinthium were investigated. Hydro-distillation was used to extract essential oil from these plants. The identification of compounds from essential oils was performed using GC–MS analysis. Camphor (28.47%) was the major compound of A. absinthium essential oil. High contents of verbenone (20.99%) and camphor (19.72%) were found in R. officinalis. In the case of T. capitatus, carvacrol (81.09%), gamma terpinene (6.61%) and caryophyllene (4.87%) were identified as the major compounds. While eugenol (24.69%), linalool (18.00%) were characteristic compounds of O. basilicum essential oil, camphor (39.10%) and farnesol (14.25%) together with bornyl acetate (12.31%) were the main constituents of A. absinthium. These oils were also subjected to a screening for their antioxidant activity and essential oil from A. absinthium showed a greater antioxidant activity (IC50?=?0.0063 mg/mL) compared to the standard Vitamin E (IC50?=?0.019 mg/mL). The antibacterial activities of the oils against seven pathogenic strains, Pseudomonas aeruginosa, Bacillus cereus, Salmonella, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Micrococcus luteus, were tested. The highest and broadest activity was shown by M. piperita; however, Ocimum basilicum was inactive against all strains. Essential oils were also evaluated for antidiabetic and anti-acetylcholinesterase activities. The IC50 values of A. herba-alba and O. basilicum against α-amylase were respectively 17.76 and 16.32 µg/mL suggesting a powerful anti-diabetic effect comparable to that of acarbose (IC50?=?14.88 µg/mL). R. officinalis, M. piperita and A. absinthium exhibited an interesting acetylcholinesterase inhibition with IC50 equal to 22, 24 and 58 µg/mL respectively. 相似文献
59.
Biostimulants from food processing by‐products: agronomic,quality and metabolic impacts on organic tomato (Solanum lycopersicum L.) 下载免费PDF全文
60.
Samah M S El‐Shafei Sally S Sakr Nagwa H I Abou‐Soliman 《International Journal of Dairy Technology》2020,73(1):126-133
This study investigated the impact of supplementing goats' milk with quinoa extracts, in the range of 5, 10 and 15 g/100 g on the milk fermentation. The properties of yoghurt produced from this milk, which include viscosity, microstructure and sensory acceptability, were assessed. The supplementation of goats' milk with quinoa extracts, particularly permeate extract, reduced the fermentation time and enhanced the viability of lactic acid bacteria. Supplementation of yoghurt with increased levels of quinoa extracts increased the apparent viscosity and changed the yoghurt protein matrix. Panellists highly accepted the yoghurt that contained quinoa permeate extract. 相似文献