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人白细胞髓过氧化物酶代谢活化致癌物4－氨基联苯

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中国药理学与毒理学杂志 1994年第3期8卷 221-226页

作者：林东昕 Kadl.,ff 福建医学院卫生系

本文研究人白细胞髓过氧化物酶（ＭＰＯ）体外代谢芳胺类致癌物４－氨基联苯（４－ＡＢＰ〕在Ｈ２Ｏ２存在下，ＭＰＯ代谢活化４－ＡＢＰ生成二种可与ＤＮＡ共价结合的代谢产物。高效液相色谱和质谱分析表明。在没有ＤＮＡ存在时４－Ａ... 详细信息

本文研究人白细胞髓过氧化物酶（ＭＰＯ）体外代谢芳胺类致癌物４－氨基联苯（４－ＡＢＰ〕在Ｈ２Ｏ２存在下，ＭＰＯ代谢活化４－ＡＢＰ生成二种可与ＤＮＡ共价结合的代谢产物。高效液相色谱和质谱分析表明。在没有ＤＮＡ存在时４－ＡＢＰ的主要代谢产物是偶氮二联苯。抗坏血酸和谷胱甘肽显著抑制活化的４－ＡＢＰ与ＤＮＡ结合。而且可将活化产物还原成４－ＡＢＰ．这些结果结合质谱资料提示活性中间产物可能是４－ＡＢＰ自由基。３２Ｐ－后标记实验证实ＤＮＡ加合物形成，用此种方法检测出８个４－ＡＢＰ－ＤＮＡ加合物。并表明ＭＰＯ介导产生的４－ＡＢＰ－ＤＮＡ加合物与细胞色素Ｐ４５０代谢产物Ｎ－羟基－４－ＡＢＰ和ＤＮＡ反应产生的加合物性质不同．这些结果提示。ＭＰＯ代谢活化途径可能在４－ＡＢＰ诱发肝外组织肿瘤过程中起一定的作用．

关键词：致癌物氨基联苯髓过氧化物酶

Impact of chosen force fields and applied load on thin film lubrication

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Friction 2021年第5期9卷 1259-1274页

作者： thi D.tA hien D.tA Kiet A.tIEU Bach h.tRAN School of Mechanical MaterialsMechatronicsand Biomedical EngineeringUniversity of WollongongNSW 2522Australia ho Chi Minh City University of technology and Education Ho Chi Minh City 800010Vietnam

the rapid development of molecular dynamics(MD)simulations,as well as classical and reactive atomic potentials,has enabled tribologists to gain new insights into lubrication performance at the fundamental ***,the impact of adopted potentials on the rheological properties and tribological performance of hydrocarbons has not been researched *** extensive study analyzed the effects of surface structure,applied load,and force field(ff)on the thin film lubrication of *** lubricant film became more solid‐like as the applied load *** particular,with increasing applied load,there was an increase in the velocity slip,shear viscosity,and *** degree of ordering structure also changed with the applied load but rather *** was also significantly dependent on the surface *** chosen ffs significantly influenced the lubrication performance,rheological properties,and molecular *** adaptive intermolecular reactive empirical bond order(AIREBO)potential resulted in more significant liquid‐like behaviors,and the smallest velocity slip,degree of ordering structure,and shear stress were compared using the optimized potential for liquid simulations of united atoms(OPLS‐UAs),condensed‐phase optimized molecular potential for atomic simulation studies(COMPASS),and ***,classical potentials,such as OPLS‐UA and COMPASS,exhibit more solid‐like behavior than reactive potentials ***,owing to the solid‐like behavior,the lubricant temperatures obtained from OPLS‐UA and COMPASS were much lower than those obtained from AIREBO and *** increase in shear stress,as well as the decrease in velocity slip with an increase in the surface potential parameterζ,remained conserved for all chosen ffs,thus indicating that the proposed surface potential parameterζfor the COMPASS ff can be verified for a wide range of atomic models.

关键词： molecular dynamics simulation force fields applied load tribofilm hydrocarbon

Micro-encapsulation of Pacific white shrimp oil as affected by emulsification condition

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Food Science and human Wellness 2014年第3期3卷 175-182页

作者： Sirima takeungwongtrakul Soottawat Benjakul Aran h-kittikun Department of Food technology Faculty of Agro-IndustryPrince of Songkla UniversityHat YaiSongkhla 90112Thailand Department of Industrial Biotechnology Faculty of Agro-IndustryPrince of Songkla UniversityHat YaiSongkhla 90112Thailand

Micro-encapsulation of shrimp oil using the mixture of whey protein concentrate(WPC)and sodium caseinate(SC)(1:1,w/w)as a wall material was carried *** impact of core/wall material ratios(1:2 and 1:4,w/w)and homogenizing pressures(13.79 and 27.58 MPa)on characteristics and stability of emulsion was *** size of emulsion oil droplets decreased with increasing homogenizing pressure(Pt was not influenced by core/wall material ratio(P>0.05).During the extended storage,particle size,flocculation factor(ff)and coalescence index(Ci)of all emulsions sharply increased,especially in emulsions prepared at 13.79 MPa with a core/wall material ratio of 1:2(Pter spray drying,micro-encapsulated shrimp oil(MSO)prepared at 13.79 MPa with a core/wall material ratio of 1:2 had the larger size than others(Pterial ratio of 1:4 with homogenizing pressure of 27.58 MPa exhibited higher encapsulation efficiency(EE)(51.3%–52.8%)than ***,both core/wall material ratio and homogenizing pressure directly affected micro-encapsulation of shrimp oil.

关键词： Shrimp oil Emulsion Pressure Encapsulation Spray drying

NADPh oxidase-1 deficiency offers little protection in Salmonella typhimurium-induced typhlitis in mice

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World Journal of Gastroenterology 2016年第46期22卷 10158-10165页

作者： Fong-Fong Chu R Steven Esworthy James h Doroshow Binghui Shen Department of Gastroenterology and hepatology The First Affiliated Hospital and College of Clinical Medicine of Henan University of Science and Technology Department of Cancer Genetics and Epigenetics Beckman Research Institute of City of Hope Center for Cancer Research and Division of Cancer treatment and Diagnosis National Cancer Institute

AIM to test whether Nox1 plays a role in typhlitis induced by Salmonella enterica serovar typhimurium(S. tm) in a mouse *** Eight-week-old male wild-type(Wt) and Nox1 knockout(KO) C57BL6/J(B6) mice were administered metronidazole water for 4 d to make them susceptible to S. tm infection by the oral route. the mice were given plain water and administered with 4 different doses of S. tm by oral gavage. the mice were followed for another 4 d. From the time of the metronidazole application, the mice were observed twice daily and weighed daily. the ileum, cecum and colon were removed for sampling at the fourth day post-inoculation. Portions of all three tissues were fixed for histology and placed in RNAlater for m RNA/c DNA preparation and quantitative real-time PCR. the contents of the cecum were recovered for estimation of S. tm *** We found Nox1-knockout(Nox1-KO) mice were not more sensitive to S. tm colonization and infection than Wt B6 mice. this conclusion is based on the following observations:(1) S. tm-infection induced similar weight loss in Nox1-KO mice compared to Wt mice;(2) the same S. tm CFU was recovered from the cecal content of Nox1-KO and Wt mice regardless of the inoculation dose, except the lowest inoculation dose(2 × 106 CFU) for which the Nox1-KO had one-log lower CFU than Wt mice;(3) there is no difference in cecal pathology between Wt and Nox1-KO groups; and(4) there are no S. tm infection-induced changes in gene expression levels(IL-1b, tNF-α, and Duox2) between Wt and Nox1-KO groups. the Alpi gene expression was more suppressed by S. tm treatment in Wt than the Nox1-KO cecum. CONCLUSION Nox1 does not protect mice from S. tm colonization. Nox1-KO provides a very minor protective effect against S. tm infection. Using NOX1-specific inhibitors for colitis therapy should not increase risks in bacterial infection.

关键词： Knockout mouse NADPh Oxidase-1 Salmonella typhimurium Goblet cells Reactive oxygen species

In vitro modulation of oxidative burst via release of reactive oxygen species from immune cells by extracts of selected tropical medicinal herbs and food plants

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Asian Pacific Journal of tropical Medicine 2012年第6期5卷 440-447页

作者： Fawzi Mahomoodally Ahmed Mesaik M Iqbal Choudhary Anwar h Subratty Gurib-Fakim Department of health Sciences Faculty of ScienceUniversity of MauritiusReduitMauritius Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi-75270Pakistan h.E.J.Research Institute of Chemistry International Center for Chemical and Biological SciencesUniversity of KarachiKarachi-75270Pakistan Biochemistry Department Faculty of SciencesKing Abdulaziz UniversityJeddahSaudi Arabia Center for Phytotherapy Research EbeneMauritius

Objective:to evaluate in vitro immunomodulating properties and potential cytotoxicity of six tropical medicinal herbs and food plants namely Antidesma madagascariense(Euphorbiaceae) (AM),Erylhroxylum macrocarpum(Erythroxylaceae)(EM),Faujasiopsis flexuosa(Asteraceae) (ff),Pittosporum senacia(Pittosporaceae)(PS),Momordica charantia(Cucurbitaceae)(MC) and Orimum tenuiflorum(Lamiaceae)(Of).Methods:Initially,the crude water and methanol extracts were probed for their capacity to trigger immune cells’ NADPh oxidase and MPO-dependent activities as measured by lucigenin- and luminol-amplified chemiluminescence,respectively; as compared to receptor-dependent(serum opsonised zymosan- OPZ) or receptor-independent phorbol myristerate acetate(PMA).Results:Preliminary screening on whole human blood oxidative buret activity showed significant and concentration-dependent immunomodulating properties of three plants AM,ff and *** investigations of the fractions on isolated human polymorphonuclear cells(PMNs) and mice monocytes using two different pathways for activation of phagocytic oxidative burst showed that ethyl acetate fraction was the most potent extract. None of the active samples had cell-death effects on human PMNs,under the assay conditions as determined by the trypan-blue exclusion *** PMA and OPZ NADPh oxidase complex is activated via different transduction pathways,these results suggest that AM,ff and Ot does not affect a specific transductional pathway,but rather directly inhibit a final common biochemical target such as the NADPh oxidase enzyme and/or scavenges ***:Our findings suggest that some of these plants extracts/fractions were able to modulate significantly immune response of phagocytes and monocytes at different steps,emphasizing their potential as a source of new natural alternative immunomodulatory agents.

关键词： traditional medicinal herbs Oxidative burst Immune cells Immunomodulation Chemiluminescence

Performance index improvement of a double-pipe cooler with MgO/water-ethylene glycol (50:50) nano-suspension

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Propulsion and Power Research 2020年第1期9卷 75-86页

作者： h.Arya M.M.Sarafraz O.Pourmehran M.Arjomandi Centre for Energy Resource Engineering Technical University of DenmarkDenmark School of Mechanical Engineering University of AdelaideSouth AustraliaAustralia

A series of tests was conducted to unlock the potential application of MgO/water-EG(ethylene glycol)nanofluids(NF)in a double-pipe heat exchanger(hEX).the overall heat transfer coefficient(htC),the inlet temperature of the working fluid,the fluid pressure drop(FPD),friction factor(ff)and the hydraulic performance index of the NF within the hEX were experimentally *** of nanoparticles(NPs)within the hex was also studied and modelled using asymptotic particulate fouling *** showed that MgO NPs can enhance the htC by 39%at Re=10500 and wt.%=0.3 in the turbulent ***,the presence of MgO NPs augmented the ff and the FPD *** former was enhanced 33.8%,while the latter was augmented by 37%both at wt.%=0.3 and at Reynolds number=*** also revealed that the formation of porous particulate fouling layer on the internal wall of the inner tube creates a fouling thermal resistance which changes asymptotically with ***,MgO/water-ethylene glycol shows a great potential to be used as a coolant within a hEX.

关键词： Forced convective heat transfer Particulate fouling heat exchanger Fouling Nanofluid

UNIVAC—LARC的高速线路——线路最佳化的经过

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电子计算机动态 1962年第3期 12-24页

作者： N·S·Prywes h·Luk ff J·Schwarz 苏振泽刘玉

引言近五年来,由于计算系统变得这样庞大复杂,计算机线路的设计已经发生了重大变化。现今的计算机线路设计者不仅应精通电子学线路,而且还应熟悉逻辑设计、所使用元件的物理性质及其生产方法。设计者必须比以前更加

关键词：最大延迟晶体管关阴通导最大相位半导体三极管最优化最佳化 LARC UNIVAC 噪声语音噪音方程方程式静算晶体三极管求和器加法器

Chem oprevention of 2-amino-1-methyl-6-phenyli-midazo[4,5-b]pyridine-induced carcinogen-DNA adducts by Chinese cabbage in rats

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World Journal of Gastroenterology 1999年第2期5卷 50-54页

作者： tAN Wen 1, LIN Dong Xin 1, XIAO Ying 2,ff Kadlubar 3 and ChEN Jun Shi 4

AIM the food-borne carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) induces colon and mammary gland tumors in rats and has been implicated in the etiology of human colorectal cancer. this study was conducted to examine the potentially preventive effect of Chinese cabbage (Brassica chinensis), a brassica vegetable most commonly consumed in China, against this carcinogen-induced DNA adduct formation in rats and its possible *** Sprague-Dawley rats were maintained for 10 days on basal diet or diet containing 20% (w/ w) freeze-dried cabbage powder prior to administration of a single dose of PhIP (10 mg/ kg) by oral gavage. Rats were sacrificed at 20 h after PhIP treatment and PhIP-DNA adducts in the colon, heart, lung and liver were analyzed using 32P-postlabeling technique. Levels of hepatic cytochrome P450 (CYP) 1A1 and 1A2, as indicated by 7-ethoxyresorufin O-deethylase and 7-methlxyresorufin O-demethylase activity, and cytosolic glutathione S-transferases (GSts) towards 1-chloro-2, 4-dinitrobenzene (CDNB) in the liver, lung and colon were *** Rats pre-treated with Chinese cabbage and given a single dose of PhIP had reduced levels of PhIP-DNA adducts in the colon, heart, lung and liver, with inhibition rates of 82.3%, 60.6%, 48.4% and 48.9%, respectively (P＜0.01). the enzyme assays revealed that Chinese cabbage induced both CYP1A1 and 1A2 activity, but the induction was preferential for CYP1A1 over 1A2 (81% vs 51%). GSt activity towards CDNB in the liver and lung, but not colon, was also significantly increased by cabbage *** the results indicate that Chinese cabbage has a preventive effect on PhIP-initiated carcinogenesis in rats and the mechanism is likely to involve the induction of detoxification enzymes.

关键词： heterocyclic amine DNA adduct Brassica vegetable colonic neoplasms cytochrome P450

Constructing a small organic molecule by using the derivative of oxadiazole for photovoltaic applications

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Optoelectronics Letters 2024年第12期20卷 728-735页

作者： hussein K.MEJBEL Abdulrsool h.AL-tAhER Fayez A.NAMAh Lafy F.AL-BADRY Department of Physics College of Education for Pure ScienceUniversity of Thi-QarNassiriya 64001Iraq Directorate-General for Education Dhi Qar Nassiriya 64001Iraq Department of Physics College of ScienceUniversity of Thi-QarNassiriya 64001Iraq

Because of their elasticity,light weight,little cost,and wide-area applications,besides a notable increase in power conversion efficiency(PCE),organic solar cells(OSCs)have recently caught the concern of numerous *** the current project,we created a variety of organic small compounds as donor materials by using Gaussian *** design approach entails swapping the core part,which is benzothiadiazole(Bt),based on a derivative of oxadiazole,as the terminals on both sides of the prototype compound(RM)with a variety of fragments to improve the electronic and optic characterization and performance for PCE in *** theoretical consideration under density-functional theory(DFt)and time-dependent density functional theory(tD-DFt)at the B3LYP/6-31G(d,p)basis set was made to find the maximum absorption wavelength λ_(max),the efficiency of light harvesting(LhE),excitation energy(E_(x)),highest occupied molecular orbital(hOMO)and lowest occupied molecular orbital(LOMO)levels,energy band gap(E_(g)),dipole moment(ρ),the density of state(DOS),ionization potential(IP),electron affinity(EA),fill factor(ff),and open circuit voltage(V_(oc))of molecules RM and tS studied in a methodical *** values revealed that proposed compounds t1t4 can be encouraging materials for manufacturing OSCs as a donor tiny compound with acceptor PC6BM to predict a rise in PCE owing to their possession of proper values for some optical and electronic features,like the lowest hOMO level,narrower band gaps,and a greater absorption wavelength compared with the reference model RM.

关键词： derivative donor orbital