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Infectious laryngotracheitis is a significant respiratory disease of chickens that causes huge economic losses due to high morbidity and mortality and reduced egg production. A real-time recombinase polymerase amplification (RPA) assay was developed to accurately detect ILTV. The specific probe and primer sets were carefully designed and screened. The real-time RPA assay was carried out at 39 °C for 30 min, and results were obtained within 15 min. The results of the specificity assay showed no fluorescence signals with other avian-related viruses. The sensitivity of the assay was 1 × 102 copies/μL. The low CV value showed that the assay was reproducible. A total of 115 clinical samples were tested using the real-time RPA assay and the real-time PCR assay in parallel; the coincidence rates of the two detection methods were 100%. The results indicated that the real-time RPA assay is a specific, sensitive, rapid, and useful tool for epidemiological studies and clinical diagnosis, especially in the field and in resource-poor areas. 相似文献
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Haijian Wang Bingtao Hao Kaixin Zhou Xiaoping Chen Songfeng Wu Gangqiao Zhou Yunping Zhu Fuchu He 《Annals of human genetics》2004,68(6):563-573
Information about linkage disequilibrium (LD) patterns and haplotype structures for candidate genes is instructive for the design and analysis of genetic association studies for complex diseases and drug response. ABCC1 and ABCG2 are genes coding for two multidrug resistance (MDR) associated transporters; they are also related to some pathophysiological traits. To pinpoint the LD profiles of these MDR genes in Chinese, we systemically screened 27 unrelated individuals for single nucleotide polymorphisms (SNPs) in the coding and regulatory regions of these genes, and thereby characterized their haplotype structures. Despite marked variations in haplotype diversity, LD pattern and intragenic recombination intensity between the two genes, both loci could be partitioned into several LD blocks, in which a modest number of haplotypes accounted for a high fraction of the sampled chromosomes. We concluded that each locus has its own genomic LD profile, but that they still share a common segmental LD architecture with low haplotype diversity. Our data will benefit genetic association studies of complex traits and drug response possibly related to these genes. 相似文献
4.
??OBJECTIVE To observe the in vivo activity of Ranti-HER, a fully human monoclonal antibody, and combined with the doxorubicin or CPT-11 in established human tumor xenografts in nude mice, and to investigate whether EGFR expression is correlated with this activity. METHODS The overall receptor of EGF was quantified by flow cytometry. The anti-tumor effects of Ranti-HER were evaluated using established, s/c human carcinoma xenografts in nude mice, and the relative growth rate of tumor was used to assess the anti-tumor activity. RESULTS A431 cells showed highly expression of EGFR by flow cytometry, SW620 showed negative expression, and EGFR were expressed positively in HT29 and SW948 cells, but both of them were showed low expression. Ranti-HER(0.25-1.0 mg) could inhibit the tumor growth in human A431 epidermoid carcinoma xenografts and dose-effect relationship was observed; Ranti-HER(1.0 mg) could also inhibit the tumor growth in human SW948 colon carcinoma xenografts, but no anti-tumor effects of Ranti-HER 1.0 mg were observed in human HT29 and SW620 colon carcinoma xenografts. Therapeutic enhancement was observed in the A431 xenografts after treatment with Ranti-HER combined with doxorubicin. For another combination regimens, Ranti-HER and CPT-11 proved to be significantly more efficacious than Ranti-HER monotherpy in SW948 xenografts. CONCLUSION Anti-tumor activity of Ranti-HER are observed in xenografts in athymic nude mice, and the activity of Ranti-HER is correlated with the EGFR expression; synergistic effects are observed when Ranti-HER is combined with chemicals compared to Ranti-HER monotherapy. 相似文献
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The penetration grade system is still widely adopted for selecting asphalt binder with desired paving performance. However, the initial material compositions of asphalt binder with the same penetration level are still different, and vary with the crude oil source and essentially result in different rheological performance. This study aimed to assess the linear viscoelastic (LVE) properties, and high- and intermediate-temperature and microscale characteristics of seven unmodified asphalt binders from different sources and countries with the same penetration level of 70. The LVE parameters were firstly evaluated followed by comparisons to various damage-based indexes. The microstructure of asphalt binders was further investigated followed by correlations between morphology and performance parameters. Experimental results indicate the |G*|/sin δ is well related to the MSCR-based non-recoverable creep compliance; furthermore, the R and |G*|·sin δ can generally represent the LAS-based failure strain and fatigue life, respectively. The viscoelastic nature of tested binders was clearly distinguished and related to rheological performance by atomic force microscopy (AFM). The roughness parameters and the phases’ content derived from AFM images showed significant correlations with LVE characteristics and fatigue resistance nature, respectively. This research provides theoretical foundations for further investigating the rheological performance and microstructure characteristics, and their correlations with asphalt binders. 相似文献
6.
目的 确定并验证以细胞表面标志物CD54作为评价指标的光致敏体外评价方法。方法 将THP-1细胞与多种光致敏剂、光刺激剂、皮肤致敏剂、皮肤刺激剂和阴性受试物分别孵育,在光照射或避光处理后,用流式细胞仪测定细胞表面标志物CD54和CD86的表达水平并统计分析,进一步确定具体的评价指标,并对该方法的准确性、特异性、灵敏度、重复性进行验证。结果 19种光致敏剂中有15种引起照射组THP-1细胞表达CD54的平均荧光强度(MFI)较非照射组显著增加(P<0.05、0.01) ,且照射组细胞表达CD54的相对荧光强度(RFI)值均在1.5以上。光刺激剂经光照射后也可引起细胞表达CD54的MFI显著增加(P<0.01) ,但经过预照射处理后,CD54的表达水平较直接照射组显著下降(P<0.01)。未经光照射条件下,皮肤致敏剂即可引起THP-1细胞表达CD54和CD86的MFI比对照组显著增加(P<0.01) ,光照后CD54的表达反而略有下降。在光照和避光条件下,皮肤刺激剂、阴性受试物(乳酸)均未引起细胞表达CD54或CD86的显著性变化。以CD54为评价指标的THP-1细胞光致敏评价方法检测光致敏剂的准确性、特异性和灵敏度分别是85.2%、100%和78.9%,具有良好的重复性。结论 确定了THP-1细胞光致敏评价方法的细胞表面标志物评价指标为CD54,判定标准为:(1)光照后THP-1细胞表达CD54的MFI较照射前显著性增加;(2)光照后THP-1细胞表达CD54的RFI≥1.5;(3)当上述条件均满足时,对受试物进行预照射处理,结果仍然满足前2条标准。 相似文献
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目的 分析阿托伐他汀致肝损伤不良反应的发生规律及特点,并进行相关性因素分析,为其安全使用提供参考。方法 对福州市长乐区医院2010—2021年74例阿托伐他汀致肝损伤不良反应报告病例进行回顾性分析,统计分析患者的一般情况、临床症状、临床分型、严重程度和转归情况等临床资料。结果 收集到的74例阿托伐他汀致肝损伤患者,男女比例1.74∶1;患者年龄33~93岁;原患疾病主要是心脑血管疾病(93.24%),发生时间平均为用药后(42.78±75.98)d,临床表现主要为乏力、纳差、皮肤巩膜黄染、腹部不适,53例患者无症状;临床分型中肝细胞损伤型比例最高为29例(39.19%)、混合型次之为27例(36.49%),胆汁瘀积型最少为18例(24.32%),RUCAM量表评分均在3分以上,14例(18.92%)≥6分;3种临床分型之间的丙氨酸氨基转移酶(ALT)、碱性磷酸酶(ALP)、γ-谷氨酰转肽酶(GGT)水平比较差异具有统计学意义(P<0.05);严重程度分级中轻度肝损伤63例(85.13%),中度肝损伤9例(12.17%),重度肝损伤2例(2.70%);停药/减量并给予保肝及对症治疗... 相似文献
8.
目的:观察麦冬水浸提液对SD大鼠胚胎/胎儿的发育毒性。方法:采用SD孕鼠,分为溶媒对照组、麦冬组,每组20只交配成功动物,于妊娠第6~17天经口灌胃给予麦冬水浸提液26.9 g.kg-1,每天1次,于妊娠第20天解剖。观察母体动物的临床症状、体重变化、黄体数、着床数、胚胎生存死亡情况、生存胎仔的体重、性别、外观、内脏及骨骼检查等指标。结果:麦冬水浸提液对SD大鼠的母体及胚胎/胎儿发育各项指标未见明显影响。结论:在本实验条件下,麦冬水浸提液未见明显的母体毒性与胚胎/胎儿发育毒性。 相似文献
9.
麦冬水煎剂的遗传毒性研究 总被引:1,自引:0,他引:1
目的采用小鼠淋巴瘤细胞试验(MLA)和小鼠骨髓微核试验(MNT)研究麦冬水煎剂的遗传毒性。方法在MLA中,3.36、6.73、13.45、26.90mg(原药材)/mL 4个浓度组在非代谢活化(-S9)和代谢活化(+S9)条件下与L5178Y细胞作用3h,表达2d,制备突变频率平板并培养12d,计数大、小细胞集落的孔教,计算总突变率(MF)和小集落突变百分率(SC%);在MNT中,每组10只ICR小鼠,雌雄各半,13.35、6.68、3.34g(原药材)/kg3个剂量组间隔24h灌胃给药2次,制作骨髓涂片,计数每只小鼠2000个嗜多染红细胞中含微核的嗜多染红细胞数,计算每组动物嗜多染红细胞微核率的平均值。结果MLA4个浓度组在+/-S9条件下诱发的MF呈现剂量相关性增加,与阴性对照组比较有统计学意义(P〈0.01),SC%与阴性对照组相仿;MNT各剂量组未显示骨髓抑制作用,诱发的微核率与阴性对照组比较未见明显增加。结论麦冬水煎剂在+/-S9条件下均可诱发L5178Y细胞tk位点突变,提示其可能存在诱变物质;但该供试品对小鼠骨髓细胞染色体无损伤,经体内代谢活化后未显示遗传毒性作用。 相似文献
10.
目的建立葛根药材中5种异黄酮类成分大豆苷元、大豆苷、葛根素、葛根素芹菜糖苷、葛根素-6″-O-木糖苷的一测多评法,验证该方法在葛根质量分析中应用的准确性及可行性。方法以葛根素为内标,分别建立葛根素与葛根素芹菜糖苷、葛根素-6″-O-木糖苷、大豆苷、大豆苷元的相对校正因子,计算葛根中葛根素芹菜糖苷、葛根素-6″-O-木糖苷、大豆苷、大豆苷元的量,实现一测多评。同时采用外标法测定葛根药材中5种异黄酮类成分的量,并比较计算值与实测值的差异,以验证一测多评法在测定中的科学性及可行性。结果各相对校正因子重复性良好,一测多评法测定结果与外标法测定结果无显著差异。结论以葛根素为内标同时测定葛根素芹菜糖苷、葛根素-6″-O-木糖苷、大豆苷、大豆苷元的一测多评法可用于葛根药材的定量分析。 相似文献