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71.
72.
Tengyang Fan Guojun Jiang Rongshu Shi Ronghua Yu Xue Xiao Di Ke 《American journal of cancer research》2022,12(4):1484
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
73.
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
74.
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
75.
目的建立气相色谱-质谱联用仪去甲伪麻黄碱、芬氟拉明、伪麻黄碱、安非拉酮、咖啡因、西布曲明、克罗帕米和士的宁等8种食欲抑制剂的定性和定量分析方法。方法采用KOH NaCl、甲醇调节液固两相对待测物的作用力,提高氯仿萃取率,应用气相色谱-质谱联用仪测定。结果检测8种食欲抑制剂的相关系数r值均在0.9 983~0.9 996之间,检出限均在0.001mg/kg~0.5mg/kg之间,回收率均在70.67%~116.08%之间,精密度均在1.00%~5.40%之间。结论该方法灵敏、准确,适用于保健品中对此8种药物的确证分析和定量分析。 相似文献
76.
血清ANCA检测对肾脏疾病患者的诊断意义 总被引:1,自引:0,他引:1
目的 进一步探讨血清中的抗中性粒细胞胞浆抗体(ANCA)检测在肾脏疾病患者中的诊断意义。方法 应用间接免疫荧光(IIF)和ELISA方法检测了205例肾脏疾病患者血清中的ANCA及其靶抗原。结果 在205例肾脏痰病患者血清中,ANCA阳性40例占19.5%,其中38例为pANCA阳性(38/205);2例为eANCA阳性(2/205)。结论 不同ANCA荧光模型与疾病种类及预后密切相关;提高pANCA与ANA荧光模型的鉴别,有助于血管炎与其它自身免疫性疾病的诊断;同时应用IIF和ELISA方法检测ANCA,可以提高ANCA检测结果的可靠性。 相似文献
77.
78.
Aggregate geometrical features directly affect asphalt pavement surface properties, which further affect the resistance to skidding of a road surface. In order to establish a relationship between the aggregate geometrical features and pavement surface properties, this paper employs an aggregate geometric characteristic evaluation system (AGCES) to describe the form property, angularity, and surface texture of aggregate particles. The geometrical feature parameters of 15 different aggregates were examined by AGCES and the corresponding surface properties of asphalt pavement prepared from the mentioned aggregates were evaluated by sand patch method, 2-Dimension Image-based Texture Analysis Method (2D-ITAM) and Walking Friction Tester (WFT), respectively. The relationships between the pavement surface property parameters and the aggregate geometric characteristic parameters studied were developed by the Levenberg-Marquarat and universal global optimization (LM-UGO). The results show that the calculated geometric characteristic parameters are in agreement with traditional manual measurement results. The pavement surface properties are significantly influenced by aggregate angularity and aggregate surface texture. Regression relationships were established to predict pavement surface properties from the aggregate geometrical features. 相似文献
79.
Tracy Jiaye Lee Yu-Ching Liu Wei-An Liu Yu-Fei Lin Hsin-Han Lee Huei-Mien Ke Jen-Pan Huang Mei-Yeh Jade Lu Chia-Lun Hsieh Kuo-Fang Chung Gianni Liti Isheng Jason Tsai 《Genome research》2022,32(5):864
The ecology and genetic diversity of the model yeast Saccharomyces cerevisiae before human domestication remain poorly understood. Taiwan is regarded as part of this yeast''s geographic birthplace, where the most divergent natural lineage was discovered. Here, we extensively sampled the broadleaf forests across this continental island to probe the ancestral species’ diversity. We found that S. cerevisiae is distributed ubiquitously at low abundance in the forests. Whole-genome sequencing of 121 isolates revealed nine distinct lineages that diverged from Asian lineages during the Pleistocene, when a transient continental shelf land bridge connected Taiwan to other major landmasses. Three lineages are endemic to Taiwan and six are widespread in Asia, making this region a focal biodiversity hotspot. Both ancient and recent admixture events were detected between the natural lineages, and a genetic ancestry component associated with isolates from fruits was detected in most admixed isolates. Collectively, Taiwanese isolates harbor genetic diversity comparable to that of the whole Asia continent, and different lineages have coexisted at a fine spatial scale even on the same tree. Patterns of variations within each lineage revealed that S. cerevisiae is highly clonal and predominantly reproduces asexually in nature. We identified different selection patterns shaping the coding sequences of natural lineages and found fewer gene family expansion and contractions that contrast with domesticated lineages. This study establishes that S. cerevisiae has rich natural diversity sheltered from human influences, making it a powerful model system in microbial ecology.The yeast genus Saccharomyces, which includes S. cerevisiae, is a powerful model system for revealing patterns of genomic variation underlying reproductive isolation and adaptation in eukaryotic microorganisms. Surveys of population genetic data have been used in S. cerevisiae to date the origin of key domestication events (Gallone et al. 2016; Duan et al. 2018; Peter et al. 2018), to determine life cycle frequencies in nature (Tsai et al. 2008), to determine the genomic basis of adaptation at continental scale (Duan et al. 2018; Peter et al. 2018), and, more recently, to establish its geographical origin and dispersal history (Xia et al. 2017). Phylogenomic analyses of the Saccharomyces sensu stricto complex and extensive sequencing of collections across the world suggest that S. cerevisiae originated in East Asia (Duan et al. 2018; Peter et al. 2018). The 1011 Genome Project—the most broad large-scale yeast population genomic study—discovered that three wild isolates from Taiwan showed an unprecedented high genetic diversity compared with populations from the rest of the world (Peter et al. 2018). Population genomics of 266 domestic and wild isolates in China revealed six wild lineages from primeval forests. The newly identified CHN-IX group represents the most diverged lineage (Duan et al. 2018). Isolates from this group and the three Taiwanese isolates were grouped into a single lineage that showed a disjunct geographic distribution (Bendixsen et al. 2021). Although considerable knowledge is available on the biogeography and population genetics of plants and animals across continents (Whittaker et al. 2017), little is known about how eukaryotic microorganisms such as S. cerevisiae disperse, establish, reproduce, and persist in nature (Liti 2015).Most S. cerevisiae biology has been based on experiments on a handful of laboratory domesticated strains, but comprehensive analyses of the ecology and evolutionary biology of S. cerevisiae in the wild are still unavailable. In nature, S. cerevisiae have been isolated from the bark, fruits, surrounding soil, and leaves of plants belonging to several different families (Naumov et al. 2013), with early reports suggesting that the yeast is most successfully isolated from the oak family Fagaceae (Sniegowski et al. 2002; Sampaio and Gonçalves 2008; Wang et al. 2012). S. cerevisiae contains high genetic diversity in certain populations, including lineage-specific variants that display clear population structures (Barnett 1992; Wang et al. 2012; Cromie et al. 2013; Strope et al. 2015; Gallone et al. 2016; Gonçalves et al. 2016; Zhu et al. 2016; Duan et al. 2018; Legras et al. 2018; Peter et al. 2018) and explain phenotypic variance similar to common variants (Fournier et al. 2019). Samples from natural habitats tend to be homozygous diploids forming unique populations with minimal genetic admixture, whereas lineages associated with human activities were likely heterozygous, containing higher ploidy and greater genetic admixture leading to a mosaic genome makeup (Diezmann and Dietrich 2009; Liti et al. 2009; Wang et al. 2012; Almeida et al. 2015). The diverse natural lineages of S. cerevisiae present in East Asia provide an excellent opportunity to study the natural diversity of this species, which was previously believed to be fully domesticated (Fay and Benavides 2005).Taiwan is a continental shelf island with the fifth highest tree density in the world (Crowther et al. 2015). Among the 13 climate-related forests types in Taiwan, five are Fagaceae-dominated natural forests on low- and mid-elevation mountains (Li et al. 2013), thus a potentially ideal natural habitat for S. cerevisiae. Taiwan also harbors a high phylogenetic diversity of flowering plants (53 out of 64 angiosperm orders present under the APG IV classification system) (Lin and Chung 2017) and endemism compared with other oceanic islands (Hsieh 2002), raising the possibility that the associated microbial populations are genetically different from their continental counterparts. Here, we set out to characterize the intra-genetic diversity, relative abundance, and distribution of S. cerevisiae in Taiwanese forests over 4 yr of broad sampling. Our study provides novel insights of the predomestication phase of S. cerevisiae and broadens our understanding of the ecological and biogeographic implications before anthropogenic impacts. 相似文献
80.
Solomon Kerealme Yeshanew Chunguang Bai Qing Jia Tong Xi Zhiqiang Zhang Diaofeng Li Zhizhou Xia Rui Yang Ke Yang 《Materials》2022,15(9)
The hot workability behavior of antibacterial Ti6Al4V-5Cu alloy was investigated using a hot compression experiment in the temperature range of 790–1040 °C and strain rate of 10−3–10 s−1 with a strain of 0.4. The deformation behavior of the alloy was characterized by Gleeble 3800 compression experiment, and the relationship among deformed microstructures and deformation parameters was established. The deformations of Ti6Al4V-5Cu alloy were temperature and strain rate-dependent. Higher temperature and lower strain rate made power dissipation efficiency (η) increase and reach 89%. The activation energies (Q) in the dual-phase (α + β) and single β phase regions were calculated as 175.43 and 159.03 kJ mol−1, respectively. In the dual (α + β) phase region, with an increase in strain rate, flow-softening behavior was dominated, however in the single β phase region such as processing at 940 °C. Flow stress increased slightly in which work-hardening behavior was dominated (especially between strain rates of 10−3–1 s−1). The deformation at various conditions exhibited different stress-strain profiles, providing an insight that work hardening and flow softening coexisted in Ti6Al4V-5Cu alloy. The relative intensity of oscillatory change in flow stress profile decreased as the strain rate decreased. The hot workability of Ti6Al4V-5Cu alloy was also accessed from the viewpoint of the sub-grain structure. 相似文献