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排序方式: 共有2071条查询结果,搜索用时 491 毫秒
1.
Vancha Harish Effi Haque Magdalena
miech Hiroaki Taniguchi Sarah Jamieson Devesh Tewari Anupam Bishayee 《International journal of molecular sciences》2021,22(9)
Xanthohumol (XH) is an important prenylated flavonoid that is found within the inflorescence of Humulus lupulus L. (Hop plant). XH is an important ingredient in beer and is considered a significant bioactive agent due to its diverse medicinal applications, which include anti-inflammatory, antimicrobial, antioxidant, immunomodulatory, antiviral, antifungal, antigenotoxic, antiangiogenic, and antimalarial effects as well as strong anticancer activity towards various types of cancer cells. XH acts as a wide ranging chemopreventive and anticancer agent, and its isomer, 8-prenylnaringenin, is a phytoestrogen with strong estrogenic activity. The present review focuses on the bioactivity of XH on various types of cancers and its pharmacokinetics. In this paper, we first highlight, in brief, the history and use of hops and then the chemistry and structure–activity relationship of XH. Lastly, we focus on its prominent effects and mechanisms of action on various cancers and its possible use in cancer prevention and treatment. Considering the limited number of available reviews on this subject, our goal is to provide a complete and detailed understanding of the anticancer effects of XH against different cancers. 相似文献
2.
3.
Eicosapentaenoic acid (EPA) production by an oleaginous fungus Mortierella alpina expressing heterologous the Δ17‐desaturase gene under ordinary temperature
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4.
Hiromichi Ichinose Masanori Taira Sachiko Furuta Hiroaki Katsuki 《Journal of the American Ceramic Society》2003,86(9):1605-1608
Niobium- or vanadium-doped anatase sols were prepared by hydrothermal treatment of 0.1 mol/dm3 peroxotitanium complex aqueous solutions dissolving 0–10 mol% niobium or vanadium at 100°C for 8 h. Niobium-doping caused the increase of lattice constants of anatase and the shape change of anatase crystal from spindle-like to cubic-like structure, but no change of the optical absorbance. Vanadium-doping caused the decrease of lattice constant of c -axis, the miniaturization of anatase crystal and the increase of optical absorbance at the wavelength from 350–700 nm. 相似文献
5.
Kasukawa A. Namegaya T. Fukushima T. Iwai N. Kikuta T. 《Quantum Electronics, IEEE Journal of》1993,29(6):1528-1535
The authors have fabricated 1.3-μm InAsP-InP separate-confinement-heterostructure (SCH) strained-layer double-quantum-well (SL-DQW) laser diodes (LDs) by metalorganic chemical vapor deposition (MOCVD). A low threshold current density of 410 A/cm 2 was obtained. The CW threshold current was as low as 1.8 mA at 20°C, and maximum CW operating temperature of 120°C was obtained. These characteristics are almost the same as those of well-designed GaInAsP-InP SL-QW LDs. Further improvement of the characteristics of InAsP-InP LDs is expected by optimizing the device structure 相似文献
6.
K Fukushima S Hara-Kuge T Ohkura A Seko H Ideo T Inazu K Yamashita 《Canadian Metallurgical Quarterly》1997,272(16):10579-10584
We found that 35S-labeled recombinant human interleukin-1beta (rhIL-1beta) binds phosphatidylinositol-specific phospholipase C-treated human placental alkaline phosphatase, phosphatidylinositol-specific phospholipase C-treated trypanosome surface variant glycoproteins, and urinary uromodulin immobilized on plates or immobilized on CNBr-activated Sepharose 4B. The interaction between rhIL-1beta and these glycoproteins was lectin-like, since it was inhibited in the presence of specific saccharides, i.e. mannose 6-phosphate or synthetic Ac-NH.CH2.CH2. PO4--->6Manalpha1-->(+/-2Manalpha1-->+/-6Manalpha1-->) propyl at about 1 microM. On the other hand, a wide variety of compounds including biantennary sugar chains derived from these glycoproteins as well as ethanolamine phosphate, inositol phosphate, mannose 6-sulfate, mannose 1-phosphate, glucose 6-phosphate, and mannitol 6-phosphate did not show any inhibitory effect at concentrations up to 1 mM. These results indicate that rhIL-1beta interacts with these glycoproteins via the mannose 6-phosphate diester of glycans on the glycosylphosphatidylinositol (GPI) anchor. Furthermore, when monolayers of polarized Madin-Darby canine kidney cells on polycarbonate filter membranes were incubated with 35S-rhIL-1beta in either the apical or basolateral chamber, 35S-interleukin-1beta was found to bind specifically to the apical membranes with a Ka value of 4.6 x 10(7) M-1, and the specific interaction was inhibited by 1 microM mannose 6-phosphate. Since the mannose 6-phosphate diester moiety exists only in the GPI glycans on plasma membranes, it was evident that interleukin-1beta can directly interact with the mannose 6-phosphate diester component of the intact glycan of GPI anchors on plasma membranes. 相似文献
7.
M Suda K Tanaka K Natsui T Usui I Tanaka M Fukushima C Shigeno J Konishi S Narumiya A Ichikawa N Nakao 《Canadian Metallurgical Quarterly》1996,137(5):1698-1705
PGE2 is one of the key molecules in the osteoblast. It is the major prostanoid in the bone, and its production is under the control of both systemic and local factors. PGE2 has been reported to have multiple actions in the osteoblast, such as growth promotion and cell differentiation. To better understand the action of PGE2 in the osteoblast, we determined the PGE receptor subtypes in MC3T3-E1, an osteoblastic cell line derived from the normal mouse calvaria. Northern blot analysis revealed that EP1 and EP4 subtypes are expressed in MC3T3-E1. In contrast, EP3 subtype was not detected by either Northern blot analysis or RT-PCR. The contribution of each subtype was evaluated by studying the effects of subtype-specific analogs on osteoblastic function at confluency and 5 days after confluency. An EP1 agonist, 17-phenyl-omega-trinor PGE2, increased DNA synthesis and decreased alkaline phosphatase activity. 11-Deoxy-PGE1, and EP2 and EP4 agonist, decreased DNA synthesis and increased alkaline phosphatase activity at both stages. Butaprost, an EP2-selective agonist, showed effects similar to those of 11-deoxy-PGE1 only at confluency. Another and more differentiated osteoblastic marker, osteocalcin production, was detectable and was stimulated by 11-deoxy-PGE1 only 5 days after confluency. The exposure of these cells to EP1 agonist changed the cell shape to a more fibroblastic appearance. These results indicate that EP1, EP4, and probably EP2 are present in MC3T3-E1 cells; EP1 promotes cell growth, and EP2 and EP4 mediate differentiation of the osteoblast. Furthermore, the decreased response to EP2-specific agonist 5 days after confluency suggests that the expression of PGE receptor subtype is dependent on the stage of osteoblastic differentiation. This is the first report to determine PGE receptor subtypes in the bone. 相似文献
8.
With the growing size and complexity of power systems, system analysis—such as transients calculation—takes much time. Hence, fast calculation methods are required. Although parallel processing is a hopeful method, there have been difficulties in the parallel solution of linear equations which appear in power-flow calculations by the Newton-Raphson method. This paper aims at the fast calculation of the power-flow problem by means of parallel processing. In order to improve the suitability to the parallel solution of the differential equation in transients calculation, we assume the use of a direct-mapping parallel processing machine to map directly the network of a power system onto a network of processors. Under this assumption, we propose a new parallel-processing-oriented method in which the linear equation is solved by linear iterations between nodes with Aitken acceleration. We simulate the method on three model power systems and compare this Parallel Iterative Method (PIN) with a Parallel Direct Method (PDM) which uses the banded matrix according to the number of operations required. As a result, we can expect that PIM may solve linear equations faster than PDM with m processors, although the PIM might be inferior to the PDM with m × m processors, where m denotes the half-band width of the banded matrix. 相似文献
9.
Y. Ohshima H.S. Ahn M. Aoki S. Awa M. Fukushima H. Hayashii X.Q. Hu T.W. Hur S. Igarashi H. Ikeda H.C. Jeong K. Kaneyuki D.Y. Kim S.K. Kim A. Kuzmin M.H. Lee S. Noguchi A. Ochi H. Sagawa N. Sato N. Sugiyama K. Tamai T. Tanimori N. Toomi T.J. Wang K. Watanabe Y. Watanabe X.C. Zhong Y.C. Zhu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):517-523
We studied the performance of a prototype electromagnetic calorimeter for the BELLE detector at the KEK proton synchrotron for an energy range of 0.25–3.5 GeV. The prototype consisted of an array of 6 × 5 CsI(Tl) crystals with 30 cm length (16.2 radiation lengths) and about 6 cm × 6 cm cross section. The scintillation light of each CsI(Tl) crystal was read out by two large-area PIN photodiodes and charge-sensitive preamplifiers attached at the rear face of the crystal. We measured the energy and position resolution for electrons and the e/π separation for two sets of matrix configurations: one corresponded to the center and the other to the edge of the barrel calorimeter. The overall performance measured by the test proves that the prototype calorimeter is satisfactory for the use in the BELLE detector. 相似文献
10.
Infrared (IR) detecting elements were prepared using positive temperature coefficient (PTC) thermistors with large temperature
coefficients of resistivity (α). Their compositions were denoted as Ba1−x
Sr
x
Nb0.003Ti0.997O3 + 1 mol % TiO2 + 0.07 mol %MnO (x=0, 0.2), and their temperature coefficients of resistivity were 78 and 50% K−1, respectively. Their IR sensing properties were measured under the self-regulating heating conditions, and were compared
with those of a detector with small α (18 % K−1). It was shown that large α was effective for controlling the element temperature by self-regulating heating and for improving
sensitivity. The responsivity,R
v
of the element withx=0.2 was 980 VW−1, and was as large as those of pyroelectric detectors. Expressions which normalize the sensitivity and the thermal time constant
were derived. From these expressions, criteria for improving some IR sensing properties were obtained. 相似文献