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61.
62.
The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury–repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and β-catenin and inhibited AEC2 differentiation by disturbing the P300–β-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases.  相似文献   
63.
Gemcitabine has been extensively applied in treating various solid tumors. Nonetheless,the clinical performance of gemcitabine is severely restricted by its unsatisfactory pharmacokinetic parameters and easy deactivation mainly because of its rapid deamination, deficiencies in deoxycytidine kinase (DCK), and alterations in nucleoside transporter. On this account, repeated injections with a high concentration of gemcitabine are adopted, leading to severe systemic toxicity to healthy cells. Accord...  相似文献   
64.
Gross chromatin imbalance and high DNA content are distinct features of various types of cancer cells. However, severe inflammation can also produce similar symptoms in cells. In this study, normal, inflammatory, and carcinoma hepatic cells were stained with 4’,6-diamidino-2-phenylindole (DAPI) and investigated by hyperspectral microscopy. DAPI is a DNA-sensitive fluorochrome. Therefore, the differences in the cellular DNA of the samples can be revealed by the corresponding fluorescence. Our experimental results demonstrate that although chromosomal disorder and high DNA content both occur in severely inflammatory and carcinoma hepatic cells, there is still a slight difference in their DNA, making their fluorescent intensity and even their spectral shapes distinguishable. Based on these spectral features, we developed a method for the precise identification of normal, inflammatory, and carcinoma hepatic cells in the field of view. The identification accuracy for these three types of cells was 99.8%. We believe that examination that combines DAPI staining with hyperspectral microscopy is a potential method for the identification and investigation of various types of cancer tissues.  相似文献   
65.
目的 观察模拟失重对人下肢脂肪体积的影响,验证磁共振水脂分离成像技术在测量人下肢脂肪容积中的可行性.方法 14名男性健康志愿者,-6°头低位卧床30 d,使用磁共振水脂分离成像(Dixon)技术采集卧床前后的下肢横断面解剖图像,测量卧床前后下肢脂肪体积.结果 与卧床前相比,卧床后所有志愿者下肢总脂肪体积及大腿段脂肪体积显著增加(P<0.001);小腿段脂肪体积呈增加趋势,但无统计学差异(P>0.05).结论 使用MRI水脂分离成像可以清晰地显示卧床前后下肢脂肪体积的变化;-6°头低位卧床30 d后下肢脂肪体积明显增加.  相似文献   
66.
目的:探讨彩色多普勒超声对医源性股动脉假性动脉瘤的诊断及治疗价值。方法对22例经皮股动脉穿刺介入术后触及搏动性肿块的患者采用二维超声、彩色多普勒超声、频谱多普勒超声检查,对声像图进行总结分析,在超声引导下压迫及注射治疗。结果本组22例假性动脉瘤彩色多普勒超声诊断与临床符合率100%(22/22),18例经超声引导下压迫治疗后瘤腔闭合,3例经瘤腔内注射凝血酶治疗取得满意疗效,总治愈率95%(21/22),1例行外科手术治疗。结论彩色多普勒超声是医源性假性动脉瘤首选的诊断及治疗方法。  相似文献   
67.
脊髓损伤尿潴留患者无创护理干预研究进展   总被引:1,自引:0,他引:1  
尿潴留是脊髓损伤患者常见的并发症之一,目前对尿潴留缺乏有效的治疗,临床上主要采用留置导尿管引流尿液,被动等待膀胱功能的恢复。由于导尿易致尿道黏膜损伤,尿道附近及尿道内存在的细菌可经损伤的黏膜进入机体,引起上行感染;通过无创护理干预来解决患者的尿潴留问题显得尤为重要,本文从促进排尿和膀胱功能训练两方面,综述了脊髓损伤患者尿潴留的无创护理干预进展。  相似文献   
68.
Studies have reported that the competing endogenous RNA (ceRNA) networks are related to disease progression and prognosis in patients with hepatocellular carcinoma (HCC). The roles and mechanisms of long-chain non-coding RNA AP003469.4 in HCC have remained unclear. Here, we explored the roles of AP003469.4 in HCC progression using bioinformatics, CCK-8, Transwell assay, etc. AP003469.4 targets miRNAs and these target genes were predicted by the LncBase Predicted v.2, miRDB, miRTarBase, and TargetScan databases. Then, AP003469.4-associated ceRNA network was constructed. Biological functions and mechanisms of differentially expressed genes in the ceRNA network were explored using GO and KEGG. Survival analysis and Cox regression analysis were used to screen prognostic genes and construct a prognostic risk model. The results revealed that AP003469.4, with the area under the curve of 0.9048, was highly expressed in HCC tissues. Increased expression of AP003469.4 was an independent risk factor for the dismal prognosis of HCC patients and was associated with the short overall and disease-free survival. Downregulation of AP003469.4 expression inhibited cell proliferation, cycle transition, invasion, and migration, and promoted cell apoptosis. There were 489 differentially expressed target genes in the ceRNA network, which were involved in several pathways, such as the MAPK signaling pathway, cell cycle, and p53 signaling pathway. The risk model was based on the DTYMK, ZFC3H1, CBX2, PKM, TTC26, ATG10, TAGLN2, CD3EAP, SHISA9, SLC1A5, KPNA2, SCML2, E2F7, and SMARCD1, which were the independent risk factors for poor prognosis of HCC patients. In general, interference with AP003469.4 expression might delay the progression of HCC. AP003469.4 related network could help to identify the hub target molecules in HCC progression, which might be candidate biomarkers for evaluating the prognosis of HCC patients.  相似文献   
69.
目的:通过测量戴稳定(牙合)垫前、后颞下颌关节腔内压力的变化,检验稳定(牙合)垫治疗对颞下颌关节腔内压力的影响.方法:用自行开发的多导颞下颌关节腔内压力测试仪,对22例患者进行戴稳定(牙合)垫前、后的颞下颌关节腔内压力穿刺测量,直接获取关节腔内的压力数值,并对戴稳定(牙合)垫前、后正中咬合和大张口状态下的压力数值用配对t检验进行统计比较分析.结果:戴稳定(牙合)垫前正中咬合和大张口状态的颞下颌关节腔内压力分别是(61.3±48.5)mm Hg(1 mm Hg=0.133 kPa)和负压(33.2±34.2)mm Hg;戴稳定(牙合)垫后正中咬合和大张口状态的颞下颌关节腔内压力为(39.5±24.5)mm Hg柱和负压(36.3±25.3)mm Hg.正中咬合状态下的戴稳定(牙合)垫后关节腔内压力值小于戴稳定(牙合)垫前压力值,两者比较差异有统计学意义(P<0.05);大张口状态下的压力数值在戴稳定(牙合)垫前、后差异没有统计学意义(P>0.05).结论:戴稳定(牙合)垫能降低正中咬合状态下颞下颌关节腔内压力.  相似文献   
70.
目的:探索生药学创新性的实验方法及培养学生的创新思维、动手能力和团队协作精神的作用。方法:在教师的指导下,成立3个学生课题小组,分别选取贵州道地药材药材天麻、杜仲、吴茱萸,通过文献查阅与综述、药材市场调查与样品收集、药材鉴定、质量评价、实验记录与报告书写等完成相应的研究工作。结果:学生掌握了如何进行文献查阅与综述,如何开展药材市场调查,怎样收集到合格的药材,如何制定实验方案,物资准备包括哪些内容,选用什么样的性状、显微、理化鉴定方法对药材进行鉴定,如何评价中药的质量,如何正确书写实验记录与报告。结论:通过具体的实验项目使学生了解进行中药品种鉴定与质量评价的基本思路、方法与程序;通过与本学科课堂理论学习结合,增加学生学习兴趣,提高学生参与科学实验的积极性,培养学生的创新思维;通过实验过程的全程参与,特别是样品收集、物资准备和实验操作的锻炼,学生的动手能力普遍提高;通过课题小组的分工与协作,锻炼学生独立从事及完成一项任务的能力,改善学生之间、学生与社会之间沟通及协作能力。  相似文献   
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