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61.
目的 观察5-氮杂-2’-脱氧胞苷(5-aza-2-deoxycytidine,5-Aza-CdR)对体外培养人涎腺腺样囊性癌(salivary adenoid cystic carcinoma,SACC)细胞系细胞O6-甲基鸟嘌呤-DNA甲基转移酶(O6-methylguanine-DNA methyhransferase,MGMT)和人类mutL同源物1(homo sapiens mutL homolog 1,hMLH1)基因表达的影响,探讨DNA甲基转移酶抑制剂应用于SACC治疗的可行性及机制.方法 用不同浓度5-Aza-CdR分别处理体外培养SACC-83和SACC-LM细胞作为药物处理组,以药物处理浓度0 μmol/L为对照组.甲基噻唑基四唑法确定5-Aza-CdR的半数抑制浓度(half maximal inhibitory concentration of a substance,IC50);实时聚合酶链反应和反转录聚合酶链反应检测用药后细胞中MGMT和hMLH1 mRNA表达水平.结果 药物处理细胞24 h后细胞形态发生变化,并且随时间延长变化愈加显著.5-Aza-CdR对SACC-83和SACC-LM细胞的IC50分别为(11.816±0.023)、(5.751± 0.049) μmol/L.经5-Aza-CdR处理后,SACC-83和SACC-LM细胞中MGMT和hMLH1 mRNA表达增高1~5倍,MGMT和hMLH1在药物处理组与对照组之间的表达差异有统计学意义(P<0.01).结论 5-Aza-CdR可改变细胞形态,上调MGMT和hMLH1 mRNA的表达,其机制可能与5-Aza-CdR反转MGMT、hMLH1基因DNA启动子区高甲基化状态有关.  相似文献   
62.
《中国肺癌杂志》2021,24(4):217
非小细胞肺癌(non-small cell lung cancer, NSCLC)是肺癌最常见的病理类型。晚期NSCLC的系统性抗肿瘤治疗经历了化疗、靶向治疗及免疫治疗的变革,患者总体生存时间不断延长。免疫检查点抑制剂(immune checkpoint inhibitors, ICIs),尤其是程序性死亡分[50;-1(programmed cell death protein 1, PD-1)/程序性死亡分[50;配体-1(programmed death-ligand 1, PD-L1)抗体已成为表皮生长因[50;受体(epidermal growth factor receptor, EGFR)/间变性淋巴瘤激酶(anaplastic lymphoma kinase, ALK)阴性晚期NSCLC一线及二线的标准治疗和局部晚期NSCLC同步放化疗后标准治疗,并在辅助/新辅助治疗中显示出可喜的结果,改变了NSCLC整体治疗格局。随着越来越多的ICIs在国内获批肺癌适应证,中国临床肿瘤学会(Chinese Society of Clinical Oncology, CSCO)NSCLC专家委员会牵头,组织该领域的专家,结合2019年版专家共识,参考最新国内外文献、临床研究数据及系统评价,在专家共同讨论的基础上,达成统一意见并制定、更新本共识,为国内同行更好地应用ICIs治疗NSCLC提供参考意见。  相似文献   
63.
64.
Nuclear pore complexes (NPCs) play an important role in coordinating the transport of proteins and nucleic acids between the nucleus and cytoplasm, and are therefore essential for maintaining normal cellular function and liability. In the present study, we investigated the temporal immunohistochemical distribution of five representative components of NPCs—Ran GTPase‐activating protein 1 (RanGap1), glycoprotein‐210 (Gp210), nucleoporin 205 (Nup205), nucleoporin 107 (Nup107), and nucleoporin 50 (Nup50)—after 90 min of transient middle cerebral artery occlusion (tMCAO) up to 28 days after the reperfusion in rat brains. Single immunohistochemical analyses showed ring‐like stainings along the periphery of the nucleus in sham control brains. After tMCAO, Gp210 and Nup107 immunoreactivity continuously increased from 1 day, and RanGap1, Nup205, and Nup50 increased from 2 days until 28 days, which also displayed progressive precipitations within the nucleus in the peri‐ischemic area, while the ischemic core showed scarce expression with collapsed structure. Double immunofluorescent analyses revealed nuclear retention and apparent colocalization of RanGap1 with Nup205, Gp210 with Nup205, and partial colocalization of Nup205 with Nup107; most of the ischemic changes above were similar to those observed in patients with C9orf72‐genetic amyotrophic lateral sclerosis. Taken together, these observations suggest that the mislocalization of these nucleoporins may be a common pathogenesis of both ischemic and neurodegenerative disease. © 2016 Wiley Periodicals, Inc.  相似文献   
65.
66.
In this paper, the original up-and-down method, modified up-and-down method, the Robbins-Monro method, and a fixed-sample Spearman-Kärber method are compared for the point estimator as well as the confidence interval of LD50. In particular, three different designs of the modified up-and-down approach based on the combination of experiments on one test space and reduced test space are investigated. The standard normal distribution and chi-square distribution are used as tolerance distributions. Simulation results indicate that the modified up-and-down method tends to be some-what better than the original up-and-down method in terms of the mean squared error under normal tolerance distribution. In case of chi-square distribution, the modified method is shown to be substantially better when the test space is wide and the initial dose is further away from the LD50.  相似文献   
67.
目的总结非编码 RNA 调控骨关节炎(osteoarthritis,OA)的分[50;生物学研究进展,为生物学研究及临床治疗 OA 提供参考。方法广泛查阅近年国内外有关非编码 RNA 调控 OA 病理过程的相关研究报道,并进行总结。结果根据 RNA 长度可将非编码 RNA 分为 3 类。相关研究采用高通量测序技术以及基因芯片技术筛选出大量与 OA 发病过程相关的非编码 RNA,并经 RT-PCR 验证此类非编码 RNA 多参与了 OA 的调控;通过对 OA 中表达最显著的非编码 RNA 进行基因敲减及过表达,明确了其调控 OA 的作用靶点;以及了解了非编码 RNA 间以及非编码 RNA 与编码 RNA 间存在复杂的基因共表达网络拓扑结构,为明确基因间结构及功能的相互作用、寻求 OA 治疗靶点提供线索。结论目前对于非编码 RNA 调控 OA 病理过程的分[50;生物学机制已有初步研究,但每个非编码 RNA 发挥调控作用的关键结构或序列,以及其效应复合结构的组建及相互作用机制仍未明确,有待进一步研究。  相似文献   
68.
69.
《Vaccine》2022,40(38):5608-5614
The majority of infectious bursal disease virus (IBDV) strains circulating in the broiler chicken industry in Canada are variant strains (varIBDV). Despite high levels of maternally derived antibodies (MtAb), the circulating varIBDVs can establish infection and cause severe immunosuppression in broiler chicks. The objective of this study was to evaluate circulating varIBDVs as broiler breeder vaccine candidates and investigate their protective efficacy against varIBDV challenge in their progeny chicks. Six groups of breeders (20 females/group) were vaccinated with varIBDV strains, SK09, SK10, SK11, SK12, and SK13 or saline at the age of 13 weeks and antibody response was determined by ELISA at 3–7-, and 20- weeks post-vaccination. We also included commercial chicks for the comparison. Results showed that SK-09 is the most antigenic strain, followed by SK-10, SK-12, and SK-13. In contrast, SK-11 showed the lowest antibody response, and over time, antibody titers steadily decreased. Eggs from breeders were collected at 21-week post-vaccination and incubated to produce their respective progenies. The serum antibody titer in day-old chicks showed a successful MtAb transfer. Progeny chicks (n = 40/group) were orally challenged with varIBDV-SK-09 strain at 6 days of age and serum antibody titer (19 d and 35 d of age), bursa to body weight ratio (19 d and 35 d of age), bursal viral load (9 d and 19 d of age) was examined to assess the protection against IBDV. Following the challenge, we found a significant increase in the antibody titers in MtAb-free and commercial vaccine groups than in the varIBDV groups, both at 19 d and 35 d of age. The BBW ratio and viral load data indicated a significant homologous and heterologous protection against varIBDV-SK-09 challenge by SK-09 and SK-10 MtAbs, respectively. Overall, this study demonstrated the feasibility of developing breeder vaccines using circulating varIBDV as candidate vaccine antigens.  相似文献   
70.
《Injury》2023,54(7):110767
AimThis network meta-analysis aims to compare functional outcomes and complications between conservative treatment and surgery for distal radius fractures in patients aged 60 years and over.MethodsWe searched the PubMed, EMBASE, and Web of Science databases for randomized controlled trials (RCTs) assessing the effect of conservative treatment and surgery for distal radius fractures in patients aged 60 years and over. Primary outcomes included grip strength and overall complications. Secondary outcomes included Disabilities of the Arm, Shoulder, and Hand (DASH) scores, Patient-Rated Wrist Evaluation (PRWE) scores, wrist range of motion and forearm rotation, and radiographic assessment. All continuous outcomes were assessed using standardized mean differences (SMDs) with 95% confidence intervals (CIs), and binary outcomes were assessed using odds ratio (OR) with 95% CIs. The surface under the cumulative ranking curve (SUCRA) was used to determine a hierarchy of treatments. Cluster analysis was performed for grouping treatments based on the SUCRA values of primary outcomes.ResultsFourteen RCTs were included to compare conservative treatment, volar lockedplate (VLP), K-wires fixation, and external-fixation. VLP outperformed conservative treatment for 1-year and minimum 2-year grip strength (SMD; 0.28 [0.07 to 0.48] and 0.27 [0.02 to 0.53], respectively). VLP yielded the optimal grip strength at 1-year and minimum 2-year follow-up (SUCRA; 89.8% and 86.7%, respectively). In a subgroup analysis of patients aged 60 to 80 years old, VLP outperformed conservative treatment in DASH and PRWE scores (SMD, 0.33 [0.10, 0.56] and 0.23 [0.01, 0.45], respectively). In addition, VLP had the fewest complications (SUCRA = 84.3%). Cluster analysis suggested that VLP and K-wire fixation were more effective treatment groups.ConclusionEvidence to date demonstrates that VLP provides measurable benefits in grip strength and fewer complications to those 60 years of age and over, and that benefit is not reflected in current practice guidelines. There is a subgroup of patients where K-wire fixation outcomes are similar to those of VLP; defining this subgroup may yield substantial societal benefits.  相似文献   
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