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81.
Tingting Ma Hao Zhang Tongxi Li Junjie Bai Ziming Wu Tianying Cai Yifan Chen Xianming Xia Yichao Du Wenguang Fu 《Phytotherapy research : PTR》2023,37(1):181-194
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway. 相似文献
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83.
Xu Li Siming Li Zhihong Chi Chuanliang Cui Lu Si Xieqiao Yan Lili Mao Bin Lian Bixia Tang Xuan Wang Xue Bai Li Zhou Yan Kong Jie Dai Jun Guo Xinan Sheng 《Urologic oncology》2021,39(1):75.e1-75.e8
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC. 相似文献
84.
Lei Xiaoli Wang Zixuan Qi Jiamin Wang Xingyuan Chen Yubao Li Bin Zhou Yue 《Bulletin of environmental contamination and toxicology》2022,109(1):110-121
Bulletin of Environmental Contamination and Toxicology - An effective method of iron extraction from bauxite residue was explored, and iron was used to prepare iron carbon composite material, which... 相似文献
85.
股骨粗隆部骨折在临床上是一种常见病及多发病,尤其是老年人更常见。本病的治疗方法很多,但随着国内外内固定材料的改进和技术的提高,大多数医生倾向于采取手术内固定治疗。我科自1999年1月-2003年1月采用AO动力髁螺钉系统手术治疗股骨粗隆部骨折共16例,疗效满意。 相似文献
86.
单片微机化微弱发光测量仪及其在肿瘤研究中的初步应用 总被引:2,自引:0,他引:2
单片微机化微弱发光测量仪由中科院生物物理所和北京科龙生物医学技术开发公司研制成功。该仪器适用于肿瘤研究中生物医学样品的微弱发光的测量。测量样品的重复性优于0.8%,稳定性优于0.5%,线性相关系数达0.9997,不仅可以进行样品的发光强度测量,还可以进行动力学曲线的测量以及样品发射光谱的测量。光谱在400nm-750nm范围内。测量方式可选择手动、半自动和自动计时三种。测量结果表明,荷瘤裸鼠血液微 相似文献
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88.
补肾中药对老年大鼠脑组织中胆碱能M受体分布的影响 总被引:1,自引:0,他引:1
采用受体放射配基结合分析、原位杂交和放射自显影术等方法,研究胆碱能M受体、M1受体mRNA在脑组织中的分布,观察补肾中药对胆碱能M受体的含量、功能及分布的影响,探讨补肾中药延缓脑组织衰老的机理.结果显示:老年大鼠大脑皮层、海马、纹状体中M受体明显减少,放射自显影的灰度值降低,胆碱能M1受体mRNA在老年大鼠纹状体部位的表达减少,在其他部位的不明显.补肾中药明显增加老年大鼠胆碱能M受体的数量,对脑内胆碱能M1受体mRNA转录水平降低的部位有改善作用.补肾中药可通过改善胆碱能M1受体的mRNA表达、增加脑内胆碱能M1受体数量来延缓脑组织衰老. 相似文献
89.
本文通过对17483例甲状腺肿大中五种甲状腺病病例的收集、分析、整理、统计与提炼,确定了诊断原则,建立了知识库、病例库和正反双向混合推理机制,完成了用Turbo-Prolog语言编制。采用适用于表示医学产生式知识表示方法所开发的专家诊断与咨询系统,为教学、临床工作及家庭保健提供了有价值的软件。经临床病例验证,该软件准确、可靠、有很强的实用价值,对人工智能的研究、临床及教学的现代化,提高人们的保健水 相似文献
90.