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排序方式: 共有1410条查询结果,搜索用时 15 毫秒
1.
Elrashdy M. Redwan Vladimir N. Uversky Esmail M. El-Fakharany Hussein Al-Mehdar 《Comptes rendus biologies》2014,337(10):581-595
Lactoferrin (LF) is an 80-kDa globular glycoprotein with high affinity for metal ions, particularly for iron. This protein possesses many biological functions, including the binding and release of iron and serves as one of the important components of the innate immune system, where it acts as a potent inhibitor of several pathogens. LF has efficacious antibacterial and antiviral activities against a wide range of Gram-positive and Gram-negative bacteria and against both naked and enveloped DNA and RNA viruses. In its antiviral pursuit, LF acts predominantly at the acute phase of the viral infection or even at the intracellular stage, as in hepatitis C virus infection. LF inhibits the entry of viral particles into host cells, either by direct attachment to the viral particles or by blocking their cellular receptors. This wide range of activities may be attributed to the capacity of LF to bind iron and its ability to interfere with the cellular receptors of both hosts and pathogenic microbes. 相似文献
2.
A. A. Moaty Sayed M. A. Hussein T. Becker 《Biomechanics and modeling in mechanobiology》2010,9(2):141-151
Lattice Boltzmann models (LBM) are rapidly showing their ability to simulate a lot of fluid dynamics problems that previously
required very complex approaches. This study presents a LBM for simulating diffusion–advection transport of substrate in a
2-D laminar flow. The model considers the substrate influx into a set of active cells placed inside the flow field. A new
innovative method was used to simulate the cells activity using the LBM by means of Michaelis–Menten kinetics. The model is
validated with some numerical benchmark problems and proved highly accurate results. After validation the model was used to
simulate the transport of oxygen substrates that diffuse in water to feed a set of active cartilage cells inside a new designed
bioreactor. 相似文献
3.
Growth characteristics of a thermotolerant methylotrophic Bacillus sp. (NCIB 12522) in batch culture
Nader Al-Awadhi Thomas Egli Geoffrey Hamer 《Applied microbiology and biotechnology》1988,29(5):485-493
Summary This contribution deals with problems associated with the culture of a thermotolerant methylotrophic Bacillus sp. The results reported clearly demonstrate why conventional enrichment/isolation procedures have, in the past, failed to allow such microbes to assert themselves. The catastrophic effect of carbon substrate (methanol) exhaustion on such cultures is clearly evidenced, but the effects of other nutrient exhaustion or limitations are demonstrated to be markedly less stringent. The failure of such cultures to complete the sporulation process when growing on methanol has important consequences with respect to their survival characteristics. 相似文献
4.
C P Dietrich H B Nader L Toma P de Azambuja E S Garcia 《Biochemical and biophysical research communications》1987,146(2):652-658
The insect Rhodnius prolixus synthesizes heparan sulfate and chondroitin sulfate after a blood meal containing [35S]-inorganic sulfate. A 40 to 80% inhibition of heparan sulfate synthesis was obtained when the meal was supplemented with 10(-5) and 10(-4) M sodium selenate respectively. Likewise an inhibition of the molting in the order of 30 to 60% was observed when the insects were fed with blood containing 10(-5) and 10(-4) M selenate respectively. The insects after a subsequent meal without selenate molted normally. Except for the inhibition of the ecdysis no gross physiological or morphological changes could be observed in the insects. Based on these and other findings the possible role of sulfated glycosaminoglycans in the control of cell growth is discussed. 相似文献
5.
Suitability of different mite prey for the development of the predatory mite,Phytoseiulus persimilis
Development of the phytoseiid mitePhytoseiulus persimilis Athias-Henriot was studied when fed on three mite species as prey. The tenuipalpid mite,Brevipalpus pulcher (Canestrini & Fanzago), is an unsuitable prey forP. persimilis as predatory larvae reared on any stages developed to the protonymphal stage only. WhenP. persimilis larvae were reared on the eriophyid mite,Eriophyes dioscoridis Soliman & Abou-Awad, only a few developed to adulthood, but failed to oviposit. On the contrary, predatory larvae fed on the tetranychid mite,Tetranychus urticae Koch, matured in a significantly shorter period and resulting females exhibited a high rate of reproduction. 相似文献
6.
Biological Seed Treatment of Corn with Mycopathogenic Fungi 总被引:2,自引:0,他引:2
7.
C P Dietrich J F de Paiva C T Moraes H K Takahashi M A Porcionatto H B Nader 《Biochimica et biophysica acta》1985,843(1-2):1-7
The isolation, some structural features, physicochemical properties and pharmacological activities of a heparin from Anomalocardia brasiliana are reported. It is shown that the mollusc heparin is very similar to those present in mammalian tissues with regard to chemical composition, physicochemical properties, pharmacological activities and susceptibility to heparinase and heparitinase II from Flavobacterium heparinum, as well as to the types of products formed by the action of these enzymes. Three significant quantitative differences were observed for the mollusc heparin when compared with the ones from mammalian origin, namely, a higher degree of binding with antithrombin III (45%), higher molecular weight (27-43 kDa) and higher anticoagulant activity (320 I.U./mg). The possible biological role of heparin is discussed in view of the present findings. 相似文献
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10.
Aly H. Rasmy H. A. Abdel-Rahman M. M. Abdek-Kader H. E. Hussein 《Experimental & applied acarology》1990,10(2):151-155
The effects of attack by the three predaceous mite speciesPhytoseiulus persimilis Athias-Henriot,Phytoseius finitimus Ribaga andAmblyseius gossipi Elbadry on the development, reproduction and mortality of the two-spotted spider miteTetranyschus urticae Koch were evaluated after the prey larvae being exposed to attack by these predators for limited periods. Development of the surviving prey immatures was significantly prolonged; this influence was more distinctive when prey larvae were exposed to the predators for a longer period. The number of prey adults which died early was positively correlated with the length of the feeding period allowed to the predators. A substantial reduction in the number of eggs deposited by the prey females was noted, although the oviposition by the prey females was noted, although the oviposition period and adult longivity were not significantly affected. 相似文献