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排序方式: 共有1110条查询结果,搜索用时 15 毫秒
41.
Keren Nitzan Leah Ellenbogen Ziv Bentulila Dekel David Motty Franko Emanuela P. Break Michal Zoharetz Alon Shamir Yosef Sarne Ravid Doron 《International journal of molecular sciences》2022,23(16)
Alzheimer’s disease (AD) is the most common form of dementia, but there is still no available treatment. Δ9-tetrahydrocannabinol (THC) is emerging as a promising therapeutic agent. Using THC in conventional high doses may have deleterious effects. Therefore, we propose to use an ultra-low dose of THC (ULD-THC). We previously published that a single injection of ULD-THC ameliorated cognitive functioning in several models of brain injuries as well as in naturally aging mice. Here, 5xFAD AD model mice received a single treatment of ULD-THC (0.002 mg/kg) after disease onset and were examined in two separate experiments for cognitive functions, neurotropic, and inflammatory factors in the hippocampus. We show that a single injection of ULD-THC alleviated cognitive impairments in 6- and 12-month-old 5xFAD mice. On the biochemical level, our results indicate an imbalance between the truncated TrkB receptor isoform and the full receptor, with AD mice showing a greater tendency to express the truncated receptor, and ULD-THC improved this imbalance. We also investigated the expression of three AD-related inflammatory markers and found an ameliorating effect of ULD-THC. The current research demonstrates for the first time the beneficial effects of a single ultra-low dose of THC in a mouse model of AD after disease onset. 相似文献
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G Shtenberg N Massad-Ivanir S Engin M Sharon L Fruk E Segal 《Nanoscale research letters》2012,7(1):443
ABSTRACT: Multifunctional porous Si nanostructure is designed to optically monitor enzymatic activity of Horseradish Peroxidase. First, an oxidized PSi optical nanostructure, a Fabry-Perot thin film, is synthesized and is used as the optical transducer element. Immobilization of the enzyme onto the nanostructure is performed through DNA-Directed Immobilization. Preliminary studies demonstrate high enzymatic activity levels of the immobilized Horseradish Peroxidase, while maintaining its specificity. The catalytic activity of the enzymes immobilized within the porous nanostructure is monitored in real time by reflective interferometric Fourier transform spectroscopy. We show that we can easily regenerate the surface for consecutive biosensing analysis by mild de-hybridization conditions. 相似文献
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Michal Pluhacek Roman Senkerik Ivan Zelinka 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2014,18(4):631-639
In this paper, the utilization of different chaotic systems as pseudo-random number generators (PRNGs) for velocity calculation in the PSO algorithm are proposed. Two chaos-based PRNGs are used alternately within one run of the PSO algorithm and dynamically switched over when a certain criterion is met. By using this unique technique, it is possible to improve the performance of PSO algorithm as it is demonstrated on different benchmark functions. 相似文献
47.
Michal Apollo 《The International journal of environmental studies》2017,74(1):129-158
Each year, millions of mountaineers visit high-mountain areas. They generate tonnes of faeces and cubic hectometres of urine annually. Thus, proper disposal of human waste is important for the conservation and appropriate management of high-mountain areas. The management can address the issue in three ways: the good (complete/non-invasive); the bad (partial/superficial); and the ugly (invasive). With use of those categories, 20 selected summits from different parts of the world have been evaluated, separately in respect to faeces and urine. It was expected that correct or incorrect disposal of human waste would depend on the changing altitude and/or development level. Disappointingly, the correlation between selection criteria (better or worse solution) and the increase of altitude does not exist. Similarly, the increase of the development level does not play a significant role, especially when urine is taken under consideration. The problem is more global than was thought. The paper makes recommendations which could lead to reduction of this problem. 相似文献
48.
Seamless service delivery for mobile users complemented with Quality of Service provisioning for their real-time applications have a hot topic in the field of mobile communication in recent years. Seamless mobility goes hand in hand with Mobile IPv6 protocol. Since many different handover schemes trying to solve the Quality of Service issues have been developed a need for means for comparison has arisen. This paper presents an enhanced universal analytical method for comparison of handover schemes. The method focuses on two important aspects influencing the handover performance—binding update cost and packet delivery cost. The use of the proposed method is presented for comparison of four most common handover schemes—MIPv6, HMIPv6, FMIPv6 and F-HMIPv6. 相似文献
49.
Sabina Kdzierska-Mieszkowska Michal Zolkiewski 《International journal of molecular sciences》2021,22(10)
This review focuses on the molecular chaperone ClpB that belongs to the Hsp100/Clp subfamily of the AAA+ ATPases and its biological function in selected bacterial pathogens, causing a variety of human infectious diseases, including zoonoses. It has been established that ClpB disaggregates and reactivates aggregated cellular proteins. It has been postulated that ClpB’s protein disaggregation activity supports the survival of pathogenic bacteria under host-induced stresses (e.g., high temperature and oxidative stress), which allows them to rapidly adapt to the human host and establish infection. Interestingly, ClpB may also perform other functions in pathogenic bacteria, which are required for their virulence. Since ClpB is not found in human cells, this chaperone emerges as an attractive target for novel antimicrobial therapies in combating bacterial infections. 相似文献
50.
Sania Saheli Ali Reza Rezvani Azim Malekzadeh Michal Dusek Vaclav Eigner 《International Journal of Hydrogen Energy》2018,43(2):685-694
The silica- and alumina-supported Co–Zn catalysts were synthesized by thermal decomposition of new inorganic precursors [Co4.32Zn1.68(HCO2)18(C2H8N)6]/SiO2 or Al2O3. A novel coordination polymer formulated as [Co4.32Zn1.68(HCO2)18(C2H8N)6] (1) was prepared using the solvothermal technique and characterized by elemental analysis, FT-infrared spectroscopy. Thermal stability of the complex 1 was investigated by thermogravimetric analysis and differential scanning calorimetry, and its structure was determined by single-crystal X-ray diffraction. Characterization of catalysts was carried out using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET specific surface area. The catalysts were evaluated for Fischer–Tropsch synthesis (FTS) in the temperature range 200–300 °C. The results revealed that the synthesized catalysts have higher selectivity to the desired products at 260 °C. The performance of the catalysts was compared to those of catalysts constructed via impregnation method and the fabricated catalysts show higher activity and selectivity than the reference catalysts. 相似文献