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1.
AIM:To investigate the effect of LY980503(a benflumetol derivative)on multidrug resistance of tumor cell line using DNA microarray.METHODS:Total RNA was extracted from multidrug resistant MCF/DOX cell line. cDNA microarray containing 320 cDNAs was used to detect the gene expression profile.RESULTS:9 down-regulated genes and 1 up-regulated gene were identified after multidrug resistant MCF/DOX cells were treated with LY980503.CONCLUSION:LY980503 can effectively reverse the resistance of MCF/DOX to DOX in vitro by adjusting the expression of multi-genes. 相似文献
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ZHANG Zhan-jun YING Kang WANG Zhong ZHANG Xiao-yan LIU Jian-xun HUANG Yan XU Li WEI Cui-e WANG Yong-yan 《园艺学报》2004,20(8):1427-1433
AIM: To investigate the genes differential expression in cortex during rat focal cerebral ischemia.METHODS: cDNA microarray chips containing numerous cDNAs were used to investigate the gene expression pattern between samples of focal cerebral ischemia and sham-control operation rats. RESULTS: Two hundred and eleven genes differentially expressed were screened out, among these genes, up-and down-regulated genes were 199 and 12, respectively. CONCLUSIONS: The analysis of gene expression pattern of focal cerebral ischemia based on cDNA microarray can realize high-throughput screening of the genes associated with the focal cerebral ischemia. The differential expression of genes may be related to the pathogenesis of focal cerebral ischemic diseases. 相似文献
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定性和定量分析一批兽药硫酸黏菌素可溶性粉中的未知添加物。照《中国兽药典》2010年版一部对该批检品用微生物检定法进行含量测定时,发现该样品的抑菌圈为虚圈,用薄层色谱鉴别该样品,未显示与标准品溶液一致的主斑点,怀疑该样品中有处方外非法添加物。采用超高效液相色谱-四级杆-飞行时间质谱(UHPLC-Q/TOF MS)对该样品进行筛查,发现疑似添加物,并使用液相色谱-二极管阵列检测(HPLC-DAD)法进行了双重确证和含量测定。该样品中非法添加物确证为磺胺氯达嗪和甲氧苄啶,添加量分别为58.5 mg/g和13.4 mg/g。本研究通过建立筛查方法为监管部门提供技术支撑,通过分析非法添加物的可能原因为打击兽药处方外非法添加提供了思路。 相似文献
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Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionless jet-to-plate distance(H/D)was 0.2,and non-dimensional nozzle-to-nozzle spacing(S/D)was 3,4,5 and 6,respectively.It is found that the quenching time is shortened at a constant total mass flow at air jet inlet m·(m·=218.21 kg/h),and the heat transfer uniformity is deterio-rated as S/D increases.However,the adding reversed-flow nozzles can shorten the quenching time of the glass plate considerably with a modest change in the heat transfer uniformity.The results at variable m·are the same as those at a fixed m·.Furthermore,the parity and arrangement of nozzles are also discussed,It is found that an odd number of nozzles is more beneficial for transient heat transfer.Based on these results,an appropriate proposal for ultra-thin glass tempering process is presented. 相似文献
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试验旨在分析绵羊初乳和常乳乳蛋白质组的差异,揭示绵羊不同泌乳阶段的乳蛋白质组特征。选用6只胎次相同、预产期相近的湖羊母羊,分别采集分娩后第1、3、7天的初乳和第14、28、56天的常乳,每个时间点采集6份奶样并等体积混合,离心弃去乳脂肪,采用双向电泳(2-DE)技术对初乳和常乳的脱脂乳蛋白进行比较分析。结果发现,初乳中乳蛋白含量较高,且随着泌乳期的延伸,乳蛋白含量降低。以第1天乳蛋白2-DE图谱为参照,第3天检测到38个差异蛋白点,其中有20个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第3天图谱中,其余17个蛋白点呈现表达量的差异;第7天检测到35个差异蛋白点,其中有19个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第7天图谱中,其余15个蛋白点呈现表达量的差异;第14天检测到34个差异蛋白点,其中有11个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第14天图谱中,其余22个蛋白点呈现表达量的差异;第28天检测到38个差异蛋白点,其中有28个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第28天图谱中,其余9个蛋白点呈现表达量的差异;第56天检测到36个差异蛋白点,其中有26个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第56天图谱中,其余9个蛋白点呈现表达量的差异。综上,共检测出44个差异表达的蛋白点,其中有8个蛋白点仅存在于第1天图谱中,而这些蛋白主要涉及免疫活性功能。 相似文献
7.
Yukako Tokutake Marcin Taciak Kan Sato Masaaki Toyomizu Motoi Kikusato 《Animal Science Journal》2021,92(1):e13604
Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs. 相似文献
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