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World Journal of Gastroenterology 2019年第18期25卷 2251-2263页

作者： Fares Ayoub donevan R Westerveld Justin J Forde Christopher E Forsmark Peter v.draganov.dennis Yang department of Medicine University of Florida division of Gastroenterology Hepatology and Nutrition University of Florida

BACKGROUNd The role of prophylactic clipping for the prevention of delayed polypectomy bleeding(dPB) remains unclear and conclusions from prior meta-analyses are limited due to the inclusion of variety of resection techniques and polyp *** To conduct a meta-analysis on the effect of clipping on dPB following endoscopic mucosal resection(EMR) of colorectal lesions ≥ 20 *** We performed a search of PubMed and the Cochrane library for studies comparing the effect of clipping vs no clipping on dPB following endoscopic resection. The Cochran Q test and I^2 were used to test for heterogeneity. Pooling was conducted using a random-effects *** Thirteen studies with a total of 7794 polyps were identified, of which data was available on 1701 cases of EMR of lesions ≥ 20 mm. Prophylactic clipping was associated with a lower rate of dPB(1.4%) when compared to no clipping(5.2%)(pooled OR: 0.24, 95%CI: 0.12-0.50, P dies(I^2 = 0%, P = 0.67).CONLUSION Prophylactic clipping may reduce dPB following EMR of large colorectal *** trials are needed to further identify risk factors and stratify high risk cases in order to implement a cost-effective preventive strategy.

关键词： Meta-analysis Clipping Endoscopic resection Endoscopic mucosal resection

In vitro and in vivo cytochrome P450 3A enzyme inhibition by Aframomum melengueta and dennettia tripetala extracts

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 645-650页

作者： Sunday O.Nduka Mathew J.Okonta daniel L.Ajaghaku Chinwe v.Ukwe department of Clinical Pharmacy and Pharmacy Management Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria department of Clinical Pharmacy and Pharmacy Management University of NigeriaNsukkaEnugu StateNigeria department of Pharmacology and Toxicology Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria

Objective: To evaluate the in vitro and in vivo inhibitory effects of two commonly used herbs, Aframomum melengueta(A. melengueta) and dennettia tripetala(d. tripetala) on CYP 3A enzymes. Methods: In vitro inhibition of the enzymes were assessed with microsomes extracted from female albino rats using erythromycin-N-demethylation assay(EMNd) method while their in vivo effects were measured by estimating simvastatin plasma concentrations in rats. Pharmacokinetic parameters were determined using non-compartmental anaysis as implemented in Win Nonlin pharmacokinetic program. Results: EMNd assay with intestinal microsomes indicated that aqueous extracts of d. tripetala and A. melengueta significantly(P d intestinal CYP 3A activity at both 50 μg and 100 μg concentrations. Petroleum ether extract of d. tripetala and ethanol extracts of A. melengueta inhibited intestinal CYP3 A activity at 100 μg but not at 50 μg concentrations. All the extracts showed an in vitrodose dependent CYP 3A inhibition with liver microsomes. In vivo analysis showed that pretreatment with the extracts enhanced systemic absorption of simvastatin with reductions in metabolizing enzymes activity as indicated in significant increases in maximal concentration, area under curve, area under moment curve and mean resident time of simvastatin(P d be used with caution especially in patients on CYP450 3A substrate medications.

关键词： Cytochrome P450 enzymes CYP 3A Enzyme inhibition Herbal extracts

Screening of antiproliferative activity mediated through apoptosis pathway in human non-small lung cancer A-549 cells by active compounds present in medicinal plants

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Asian Pacific Journal of Tropical Medicine 2018年第12期11卷 666-675页

作者： Nutan v.Badgujar Kinnari N.Mistry dharamshibhai N.Rank Chaitanya G.Joshi Ashok and Rita Patel Institute of Integrated Study and Research in Biotechnology and Allied Sciences (ARIBAS) Affiliated to Sardar Patel University department of Animal Breeding and Genetics College of Veterinary Science and Animal Husbandry Anand Agricultural University department of Animal Biotechnology College of Veterinary Science and Animal Husbandry Anand Agricultural University

Objective: To explore the antiproliferative activity and apoptosis in cells caused by active compounds present in plants using different techniques. Methods: We investigated the antiproliferative effects of methanolic extracts from different parts of seven plants on A-549(lung cancer) cells and primary cell culture(chick embryo fibroblast cells, as normal cells) using MTT assay and the potent plant was fractioned further. All these fractions were screened again for anti-proliferative activity. dNA fragmentation and dAPI staining were used to study apoptosis. Quantitative real-time was used to investigate the expression of apoptoticrelated genes. LC-MS and 1 H-NMR techniques were used to identify the active compounds present. EnzCheck caspase-3 assay kit was used to measure caspase-3 activity. Results: Methanolic extract of vitex negundo(v. negundo) was selected as a potent fraction. Among all fractions screened, ethylacetate fraction of v. negundo was selected as the most potent antiproliferative fraction and phytochemical analysis of the extract revealed the presence of secondary metabolites. Ethaylacetate fraction of v. negundo was found to cause characteristic apoptotic morphological changes and generation of ROS in A-549 cells. Ethaylacetate fraction of v. negundo also induced apoptosis in A-549 which was supported by dNA fragmentation and dAPI staining. To investigate the molecular mechanism behind the cytotoxic effect of ethaylacetate fraction of v. negundo, quantitative real-time PCR was used to measure expression levels of p53, bax, bcl2, casp-3 and casp-9. Using LC-MS and 1 H-NMR techniques, cytotoxic compounds(luteolin and p-hydroxy benzoic acid) were identified which increased casp-3 activity in a dose and time-dependent manner in A-549 treated cells. Conclusions: It is concluded from the present study that v. negundo is capable of triggering growth-inhibitive and apoptosis effects in A-549 cells, signifying that v. negundo may possesses anti-lung cancer

关键词： Apoptosis dNA fragmentation assay ROS MTT assay Real time assay dAPI staining

Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations

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Journal of Rare Earths 2013年第9期31卷 837-842页

作者： Uygun v.valiev John B.Gruber Anvar K.Mukhammadiev vasiliy O.Pelenovich 付德君 Gary W.Burdick Faculty of Physics National University of Uzbekistan department of Physics and Astronomy The University of Texas at San Antonio School of Physics and Technology Wuhan University department of Physics Andrews University

Spectra of absorption, luminescence, magnetic circular dichroism （MCd）, and magnetic circular polarization of lumines- cence （MCPL） in Gd3Ga5O12：Eu3＋ and Eu3Ga3O12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole （Md） and electro-dipole （Ed） 4f→4f transitions occurring between Stark sublevels of the 7FJ （J=1, 2） and 5d0 multiplets in Eua＋-containing garnet structures. Quantum mechanical ＂mixing＂ had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3＋ ion for Eu3GasOl2 in MCd due to forbidden Md transition 7F1→Sd0 and for GdaGasOiE：EU3＋ in MCPL due to Md 4f→4f transition 5do→7F1 and forced Ed-transition 5do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f（6） ground electronic configuration of Eu3＋ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, Bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 mev.

关键词： : magnetic circular dichroism magnetic circular polarization luminescence adsorption garnet non-Kramers ion rare earths

To the Schwarzschild Solution in General Relativity

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Journal of Modern Physics 2018年第14期9卷 2482-2494页

作者： valery v. vasiliev Leonid v. Fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the history of the spherically symmetric static problem solution of General Relativity found in 1916 by K. Schwarzschild [1] [2] which is interpreted in modern physics as the background of the objects referred to as Black Holes. First, the modern interpretation this solution which does not exactly coincide with original solution obtained by K. Schwarzschild is discussed. Second, the basic equations of the original Schwarzschild solution are presented in modern notations allowing us to compare existing and original solutions. Finally, a modification of the Schwarzschild approach is proposed allowing us to arrive at the exact solution of the Schwarzschild problem.

关键词： General Relativity Spherically Symmetric Problem Schwarzschild’s Solution Black Holes

Use of dynamical Systems Modeling to Hybrid Cloud database

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International Journal of Communications, Network and System Sciences 2013年第12期6卷 505-512页

作者： Evgeniy v. Pluzhnik Evgeny v. Nikulchev Moscow Technological Institute (WTU) Moscow Russia

In the article, an experiment is aimed at clarifying the transfer efficiency of the database in the cloud infrastructure. The system was added to the control unit, which has guided the database search in the local part or in the cloud. It is shown that the time data acquisition remains unchanged as a result of modification. Suggestions have been made about the use of the theory of dynamic systems to hybrid cloud database. The present work is aimed at attracting the attention of specialists in the field of cloud database to the apparatus control theory. The experiment presented in this article allows the use of the description of the known methods for solving important practical problems.

关键词： Hybrid Cloud database Cloud Computing Time of Query dynamical Systems Control Theory

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模型研究改进两座土耳其沉沙池

水利水电快报 2001年第21期22卷 26-28页

作者： d.Yildiz v.ozaydin [土耳其] [土耳其]

灌溉工程的运行和维护费用在很大程度取决于沉沙池的拦沙效率.悬浮泥沙的性能,含沙量和沉积的颗粒尺寸是规划阶段需要确定的重要参数.通过对Serderabat分水堰和两个沉沙池的模型研究,设计了一些提高拦沙效率70%以上的革新性建筑物.

关键词：沉沙池水工模型试验土耳其灌溉工程拦沙效率颗粒尺寸 Serderabat分水堰

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适用已耕地的拖车轮胎选择的预测模型(上)

国外拖拉机 1982年第2期 8-11页

作者： v.d.Perdok 史滦平

一、引言目前,由于大型农业机械的使用,势必采用载重能力100～150千牛顿的自卸拖车,以利高效运输所收获的农产品。对拖车的轮胎应引起格外重视,在荷兰秋天那样潮湿松软的土壤上使用拖车,轮胎问题尤其显得重要。轮胎的正确选择取决于... 详细信息

一、引言目前,由于大型农业机械的使用,势必采用载重能力100～150千牛顿的自卸拖车,以利高效运输所收获的农产品。对拖车的轮胎应引起格外重视,在荷兰秋天那样潮湿松软的土壤上使用拖车,轮胎问题尤其显得重要。轮胎的正确选择取决于如成本、行距和

关键词：潮湿农业滚动阻力拖车挂车土壤参数刚性试验力学性能试验耕地耕种用地农业用地

Effects of holistic grazing management on milk production,weight gain,and visitation to grazing areas by livestock and wildlife in Laikipia County,Kenya

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Ecological Processes 2016年第1期5卷 216-227页

作者： Priscilla K.Lalampaa Oliver v.Wasonga daniel I.Rubenstein Jesse T.Njoka Faculty of Agriculture Department of Land Resource Management and Agricultural TechnologyUniversity of NairobiP.O.Box 29053-00625NairobiKenya Princeton University PrincetonNJ 08544-2016USA

Background:Grazing is an important management tool for maintaining healthy ecosystems and improving rangelands ***,its effectiveness for this purpose is dependent on timing and frequency of grazing,as well as the type of *** the effects of grazing management on rangeland ecosystems is critical in ensuring sustainable use of grazing resources and enhanced livestock *** study assessed the effects of holistic grazing on animal productivity and range use pattern in Laikipia County of ***:The results revealed that the average milk yields(106±20.1)of animals in holistic grazing areas(HGA)were significantly(pditional grazing areas(TGA)(101±20.1).Weight gain of animals in HGA was significantly(0.13±0.01)higher as compared to those in TGA(0.07±0.01).The number of livestock grazing was significantly(pddition,the number of wildlife grazing was significantly(pdicate that holistic grazing management has the potential to improve animal performance,as well as condition of range areas as ev.dent in the preference shown by frequent visits to HGA by both livestock and wildlife.

关键词： Camera traps Continuous grazing Animal performance Rest periods Wildlife visits

Biodiversity, dynamics, and impact of chakras on the Ecuadorian Amazon

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Journal of Plant Ecology 2019年第1期12卷 34-44页

作者： Roy R.vera v J.Hugo Cota-Sánchez Jorge E.Grijalva Olmedo University of Saskatchewan Department of Biology112 Science PlaceSaskatoon SK S7N 5E2Canada University of Saskatchewan Department of Biology and W.P.Fraser Herbarium(SASK)112 Science PlaceSaskatoon SK S7N 5E2Canada Universidad Central del Ecuador Facultad de Medicina Veterinaria y ZootecniaJerónimo Leiton y Gatto SobralQuito 170521Ecuador Estación Experimental Santa Catalina Panamericana Sur Km1Instituto Nacional de Investigaciones AgropecuariasMejía 171101Ecuador

Aims deforestation and biodiversity loss are two alarming,closely related problems,and the main factors triggering changes in land *** agricultural practices in the western Amazon Basin are known as chakras,and their structure and dynamics are seemingly optimal for forest ***,the variability in tree spe-cies and the degree of forest recovery after abandonment is poorly documented in this agroforestry system(AFS).The goals of this study were:(i)to investigate whether the different AFSs(chakras)preserve similar levels of forest diversity,(ii)to determine the effect of trans-formation of mature forests(MF)to chakras,in particular,forest alpha and beta diversity levels,and(iii)to investigate whether native tree species recovery leads to the original forest structure following chakra *** We assessed the floristic composition in three AFSs(cassava,corn,and cocoa),the secondary forest(SF),and the forest remnants in the buffer zone of the Northern Ecuadorian Amazon(NEA).All tree spe-cies with a diameter at breast height(dbh)≥10 cm were inventoried in 61 plots(0.28 ha average)representing 17.44 *** diversity was calculated in all systems to determine the levels of variabil-ity using species richness and the Shannon diversity ***,beta diversity was examined to evaluate the degree of dissimilarity among all AFSs with the MF in order to analyze changes in floristic *** divergence between the SF and the MF was ana-lyzed to ascertain forest recovery after chakra *** Findings A total of 4,060 trees(dbh≥10 cm)representing 109 species,96 genera,and 43 plant families were inventoried in 17.44 ha sampled in five systems in the buffer zone of the *** most dominant plant families were Arecaceae,Myristicaceae,Fabaceae,Meliaceae,and Malvaceae,and the most representative genera included Iriartea,virola,Guarea,Ocotea,Cordia,Chrysophyllum,and *** MF in this zone is composed of 81 tree species circums

关键词： agroforestry biodiversity chakra climate change tropical forest