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41.
宫颈癌患者血浆中E-钙黏着蛋白基因启动子区的甲基化状态 总被引:1,自引:0,他引:1
肿瘤细胞可以释放DNA进入患者的血浆/血清中,并可作为无创伤性诊断肿瘤的标记物。采用甲基化特异性聚合酶链式反应(MS-PCR)结合亚硫酸盐测序法对151例宫颈癌患者血浆和对应的30例组织中E-钙黏着蛋白基因启动子区甲基化状态进行检测,并与化学发光法检测患者血清的鳞状上皮癌抗原(SCC)相比较,发现此方法的灵敏度为40.39%,特异性为100%,正确性为49.72%,血浆和组织的符合率为76.67%。宫颈炎、子宫肌瘤和正常人的血浆中均未检测到甲基化状态的存在。随着临床分期和组织学分级的增加,E-钙黏着蛋白基因甲基化的检出率也在逐渐增加,与SCC结果相比,MS-PCR方法在早期和恶性度高的宫颈癌中的诊断效果良好。使用E-钙黏着蛋白基因作为分子标记可以对宫颈癌患者进行无创伤性早期诊断和预后的评估。 相似文献
42.
C Xie Xc ZS Zhou X Xae Xee N Li Xe Y Bian X YJ Wang Xb Xc Xefa LJ Wang Xb Xed Xaf BL Li Xe Xff Xf BL Song Xbb Xfdd Xeae 《Journal of lipid research》2012,53(10):2092-2101
The multiple transmembrane protein Niemann-Pick C1 like1 (NPC1L1) is essential for intestinal cholesterol absorption. Ezetimibe binds to NPC1L1 and is a clinically used cholesterol absorption inhibitor. Recent studies in cultured cells have shown that NPC1L1 mediates cholesterol uptake through vesicular endocytosis that can be blocked by ezetimibe. However, how NPC1L1 and ezetimibe work in the small intestine is unknown. In this study, we found that NPC1L1 distributed in enterocytes of villi and transit-amplifying cells of crypts. Acyl-CoA cholesterol acyltransferase 2 (ACAT2), another important protein for cholesterol absorption by providing cholesteryl esters to chylomicrons, was mainly presented in the apical cytoplasm of enterocytes. NPC1L1 and ACAT2 were highly expressed in jejunum and ileum. ACAT1 presented in the Paneth cells of crypts and mesenchymal cells of villi. In the absence of cholesterol, NPC1L1 was localized on the brush border of enterocytes. Dietary cholesterol induced the internalization of NPC1L1 to the subapical layer beneath the brush border and became partially colocalized with the endosome marker Rab11. Ezetimibe blocked the internalization of NPC1L1 and cholesterol and caused their retention in the plasma membrane. This study demonstrates that NPC1L1 mediates cholesterol entering enterocytes through vesicular endocytosis and that ezetimibe blocks this step in vivo. 相似文献
43.
I Feinkohl N Sattar P Welsh RM Reynolds IJ Deary MW Strachan JF Price;on behalf of the Edinburgh Type Diabetes Study 《PloS one》2012,7(9):e44569
Background
Type 2 diabetes mellitus is associated with risk of congestive heart failure (CHF), cognitive dysfunction and depression. CHF itself is linked both to poor cognition and depression. The ventricular N-terminal pro-brain natriuretic peptide (NT-proBNP) is a marker of CHF, suggesting potential as a marker for cognitive impairment and/or depression. This was tested in the Edinburgh Type 2 Diabetes Study (ET2DS).Methodology and Principal Findings
Cross-sectional analysis of 1066 men and women aged 60–75 with type 2 diabetes. Results from seven neuropsychological tests were combined in a standardised general cognitive ability factor, ‘g’. A vocabulary-based test estimated pre-morbid cognitive ability. The Hospital Anxiety and Depression Scale (HADS) assessed possible depression. After adjustment for age and sex, raised plasma NT-proBNP was weakly associated with lower ‘g’ and higher depression scores (ß −0.09, 95% CI −0.13 to −0.03, p = 0.004 and ß 0.08, 95% CI 0.04 to 0.12, p<0.001, respectively). Comparing extreme quintiles of NT-proBNP, subjects in the highest quintile were more likely to have reduced cognitive ability (within the lowest tertile of ‘g’) and ‘possible’ depression (HADS depression ≥8) (OR 1.80; 95% CI: 1.20, 2.70; p = 0.005 and OR 2.18; 95% CI: 1.28, 3.71; p = 0.004, respectively). Associations persisted when pre-morbid ability was adjusted for, but as expected were no longer statistically significant following the adjustment for diabetes-related and vascular co-variates (β −0.02, 95% CI −0.07 to 0.03, p>0.05 for ‘g’; β 0.03, 95% CI −0.02 to 0.07, p>0.05 for depression scores).Conclusion
Raised plasma NT-proBNP was weakly but statistically significantly associated with poorer cognitive function and depression. The prospective phases of the ET2DS will help determine whether or not NT-proBNP can be considered a risk marker for subsequent cognitive impairment and incident depression and whether it provides additional information over and above traditional risk factors for these conditions. 相似文献44.
Jie SHEN * Dong Bao YU * Chinese Center for Disease Control Prevention China Division of Policy Study Information National Center for AIDS Prevention Control China 《Cell research》2005,(Z1)
EVOLUTION OF THE GOVERNMENT POLI- CIES Looking back 20 and more years, one could have hardly imagined that such great changes would have happened to the governmental policies on HIV/AIDS in China. In the earlier phase of the epidemic, laws and regulations were drafted based on the practices and experiences of preven- tion and control of other infectious diseases, such as isolation, quarantine and compulsory testing and examina- tions etc. When the HIV/AIDS epidemic was firstl… 相似文献
45.
Yang Ping He Yu-quan Zeng Hong Ni Jin-song Yun Qing-jun Huang Xiao-ping Li Shu-mei .Cadiovascular Department China-Japan Union Hospital of Jilin University Changchun P. R. China . Department of Pathdogy School of Basic Medical Sciences of Jilin University Changchun P. R. China . Cardiovascular Department Second Hospital of Jilin University Changchun P. R. China 《仿生工程学报(英文版)》2005,2(2):87-91
1Introduction Congestiveheartfailureisamultipleaetiology,high prevalence,cardiovasculardisorderwithpoorprognosis. Medicaltreatmentofdilatedcardiomyopathyisaimedat alleviatingthesymptomsofheartfailure.Diuretics,ACE inhibitorsandbeta blockershavefavourableeffectson symptoms,exercisecapacityandmortality[1-3].Growth hormone(GH)andinsulin likegrowthfactor(IGF) 1 areinvolvedinseveralphysiologicalprocessessuchas thecontrolofmusclemassandfunction,bodycomposi tionandtheregulationofnutrientmetaboli… 相似文献
46.
Shi Wei-ping Ren Lu-quan Tian Li-mei .The Key Lab of Terrain-Machinery Bionic Engineering 《仿生工程学报(英文版)》2005,(3)
1IntroductionAdhesive forces exist between soil and the surfacesof soil-engaging components[1,2].Soil adhesion increasesthe running resistance and energy consumption,andaffects the operating quality.Soil adhesion also reducesthe working productivity of terrain machines,even worseit makes terrain machines fail to run.Reducing theadhesive force of the soil-engaging machines will have aprofound influence for cultivation.Through theinvestigation of soil animals,we have found that soilanimals poss… 相似文献
47.
Li YANG Jiang CHEN Catherine C. Y. CHANG Xin-Ying YANG Zhen-Zhen WANG Ta-Yuan CHANG and Bo-Liang LI* State Key Laboratory of Molecular Biology Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai China Department of Biochemistry Dartmouth Medical School Hanover NH USA 《Acta biochimica et biophysica Sinica》2004,(4)
Acyl-coenzyme A:cholesterol acyltransferase (ACAT)is an integral membrane protein, which is mainly locatedin rough endoplasmic reticulum (ER), and is responsiblefor catalyzing the intracellular formation of cholesterylester from cholesterol and long-chain fatty acyl-coenzymeA [1,2]. Human ACAT1 cDNA K1 was firstly cloned andfunctionally expressed in 1993 [3]. Further studies withspecific anti-ACAT1 antibody (DM10) illustrated that onemajor 50 kD ACAT1 protein was expressed in various… 相似文献
48.
ZHENG Junfang LIU Guirong ZHU Wanfu ZHOU Yuguang & LIU Shulin . Department of Microbiology School of Basic Medical Sciences Peking University Beijing China . Department of Microbiology Infectious Diseases University of Calgary Calgary ABTN N Canada . Institute of Microbiology Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2004,47(3):268-278
Rhizobiaareagriculturallyandenvironmentallyimportantbacteria.Theirsymbiosiswithleguminousplantsisresponsibleformostoftheatmosphericni-trogenfixedonland.Classificationofthesebacteriabasedontheirnaturalrelationshipswillpromotetheirapplication.Thisresearchemploysanewphylogeneticmethod,i.e.,revelationandcomparisonofgenomestructure,tocategorizerhizobia.Phylogenyisthestudyoftheevolutionaryrelationshipsamongorgan-isms[1].Currentlyphylogeneticrelationshipsamongrhizobiaaremostlyinferredfromcomparisons… 相似文献
49.
Differentiation potential of bone marrow mesenchymal stem cells into retina in normal and laser-injured rat eye 总被引:5,自引:0,他引:5
ZHANG Jie SHAN Qing MA Ping JIANG Yanming CHEN Peng WEN Jingxia ZHOU You QIAN Huanwen & PEI Xuetao . Beijing Institute of Radiation Medicine Beijing China . Beijing Institute of Transfusion Medicine Beijing China 《中国科学:生命科学英文版》2004,47(3):241-250
Withinthebonemarrowstromathereexistsasubsetofnonhematopoieticcellsreferredtoasmes-enchymalstemormesenchymalprogenitorcells.Mesenchymalstemcells(MSCs)areapopulationofpluripotentcellswithinthehuman,birdorrodentbonemarrowmicroenvironmentdefinedbytheirability,eitherinvitroorinvivo,todifferentiateintocellsoftheosteogenic,chondrogenic,tendonogenic,adipo-genic,neuralcellsandmyogeniclineages[1].Themethodologiestoisolateandculture-expandMSCsfromhumanbonemarrowforestablishingthecellularortissuediffere… 相似文献
50.
CHENG Lingpeng CHEN Senxiong Jenifer M. Brannan Joanita Jakana ZHANG Qinfen Z. H. Zhou & ZHANG Jingqiang . State Key Laboratory for Bio-control Zhongshan University Guangzhou China . Department of Pathology Medicine University of Texas-Huston Medical School Huston TX USA . National Center for Macromolecular Imaging Baylor College of Medicine Houston TX USA 《中国科学:生命科学英文版》2004,47(3):224-228
Apreviously-unknownviruswasfoundchroni-callyinfectingC6/36cellsthatwereusedtoculturedenguevirus.Afterisolationandpurification,RT,PCRandsequencingwereperformedwithrandomprimers.TheresultsshowthattheviralgenomeisssDNAandis4096ntinlength(GenBankAccessionNo.AY095351).Thenucleicacidsequenceofthispreviously-undescribedvirussharesabout90%iden-titywiththatofAedesaegyptidensonucleosisvirusandtheaminoacidsequencesofthreeproteinsen-codedbythenucleicacidshareabout89%—93%identitieswiththoseofAedesa… 相似文献