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Telomeric repeat‐containing RNA (TERRA) is closely involved in the regulation of telomere length, which plays critical roles in tumorigenesis. However, the biological significance of TERRA in hepatocellular carcinoma (HCC) remains largely unknown. In this study, we found that HCC cells show a frequent downregulation of TERRA and its positive regulator TTAGGG repeat binding factor‐1 (TRF1), whereas the negative regulator TTAGGG repeat binding factor‐1 (TRF2) was upregulated. We found that TERRA, TRF1, and TRF2 contributed to poor prognosis of HCC patients. Importantly, we found that the downregulation of TERRA significantly promoted HCC cell growth and metastasis in vitro and in vivo, whereas the upregulation of TERRA showed an opposite effect. Mechanistically, downregulation of TERRA significantly increased telomerase activity and promoted telomere elongation. Moreover, the inhibitory effects of TERRA overexpression on the growth and metastasis of HCC cells were reversed by treatment with TA‐65 that activates telomerase activity. In contrast, the protumor effect of TERRA downregulation was reversed by treatment with TMPyP4 that inhibits telomerase activity. Our findings reveal that TERRA plays a critical role in HCC cell growth and metastasis, indicating that TERRA is a potential therapeutic target for HCC.  相似文献   
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手术切除是胸腺瘤最重要的治疗手段,然而,术后辅助放疗的作用一直存在不同争议。二维放疗时代多数获益不明显,精准放疗技术已使肿瘤放疗发生了较大的变化,胸腺瘤术后放疗价值也可能在改变。目前,放疗在手术切缘阳性或无法行手术切除者的作用是肯定的;在完整手术切除者中,Masaoka-Koga分期Ⅰ期患者无需术后辅助放疗,Ⅱ期患者术后辅助放疗作用争议较大,如果放疗宜考虑Ⅱb期、大体积、B2/B3型等因素;Ⅲ期术后辅助放疗也存在争议,但是多数结果倾向行术后放疗。术后辅助放疗宜采用精准放疗技术,照射范围建议瘤床三维外扩0.5 cm,肿瘤累及的纵隔胸膜及沿纵隔胸膜前后、头脚方向0.5~1.0 cm,肺侧纵隔胸膜为0.5 cm以内,以及肿瘤周血管壁和部分血管间隙,避免包括过多的正常组织。剂量在完全切除时为45~50Gy,非完全切除为54~60Gy或稍高,可能会使放疗获益增加和风险下降。质子、重离子等新型放疗技术的应用可获得剂量学方面的优势,是否能转化为临床获益还需进一步探究。  相似文献   
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目的 探讨早期接触临床对提高医学生综合能力及强化职业认知的作用。方法 选择本校2014级儿科专业五年制学生,其中在大二结束的暑假开展早期接触临床教学活动的学生为实验组(78名),未参加的学生为对照组(81名)。在活动结束后,对参加教学活动的学生进行问卷调查。同时对该年级学生小儿外科学理论课成绩及临床实习表现进行统计分析。结果 超过90%的学生对早期接触临床教学活动满意,认为该活动有助于提高医学生的临床思维、强化职业认知、增强学习兴趣、提高沟通技能、促进基础与临床知识相结合。同时,后期追踪分析发现,早期接触临床活动可以提高学生理论课考试成绩,实验组学生临床工作熟练度、临床思维、动手能力及医患沟通能力均优于对照组。结论 在医学生中开展早期接触临床活动,能够提高学生的综合能力,有利于培养医学生的临床思维能力及医患沟通能力,强化职业认知,为医学教育培养高素质人才奠定良好基础。  相似文献   
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The microRNA miR‐8‐3p is conserved among insects and closely involved in development and immunity, but its functions in vivo are unexplored in the red flour beetle, Tribolium castaneum. Here, we show that miR‐8‐3p was highly expressed in late larva and early adult stages, as determined by quantitative real‐time PCR. It was enriched in the fat body and cuticle in late larval tissues and abundant in the head and cuticle in early adult tissues, indicating this microRNA plays important roles during T. castaneum development. Specific inhibition of miR‐8‐3p in late larvae led to metamorphosis defects in the development of wings, eyes, legs and embryo. Moreover, a series of genes related to organism development were identified as miR‐8‐3p targets by computational prediction and microRNA–messenger RNA interaction validation, including Wingless, Eyg, Fpps and Sema‐1a. These genes were critical for the regulation of the larva‐to‐adult transition. Eyg, as a functional target of miR‐8‐3p, participates in eye development, which was further confirmed by luciferase assay and loss‐of‐function analyses. In brief, miR‐8‐3p is broadly involved in the development of wings, eyes and legs through its target genes and has extensive regulatory roles during T. castaneum development.  相似文献   
7.
病机是认识疾病病变的关键,抓住核心病机演变发展的规律,是中医临床诊疗的主旨和核心。病机兼化理论由中国中医科学院胡镜清研究员提出,用以从病机层面理解疑难复杂疾病病证关系和把握其演变规律,在明确疾病基本矛盾的同时,兼顾疾病的复杂性和多变性。文章通过构建新型冠状病毒肺炎病机兼化框架,揭示其病机演化规律,认为新冠肺炎属于“湿毒疫”范畴,湿毒始终是本病的病变核心,初期寒化,进展期热化,恢复期虚化是本病病机的传变方式。知本病之机,可未病先防,知病机传变,可截断扭转,有利于临床上增强对疾病发生发展趋势的预见性。  相似文献   
8.
Background: Previous genome-wide association study (GWAS) has revealed the association between MYP10 at 8p23 and MYP15 at 10q21.1 and high myopia (HM) in a French population. This study is managed to discover the connection between some single nucleotide polymorphism (located at MYP10 and MYP15) and Han Chinese HM.

Methods and Results: This case-control association study contained 1673 samples, including 869 ophthalmic patients and 804 controls. Twelve tag SNPs have been selected from the MYP10 and MYP15 loci and genotyped by SNaPshot method. Among 12 SNPs, rs4840437 and rs6989782 in TNKS gene were found significant association with HM. Carriers of rs4840437G allele and rs4840437GG genotype created a low risk of high myopia (P = .036, OR = 0.81, 95%CI = 0.71–0.93; P = .016, OR = 0.73, 95%CI = 0.56–0.96; respectively). Carriers of rs6989782T allele and rs6989782TT+CT genotype also had a decreased risk of high myopia (P = .048, OR = 0.82, 95%CI = 0.71–0.94; P = .006, OR = 0.74, 95%CI = 0.59–0.92; respectively). Other 10 SNPs displaced nonsignificant association with HM. Additionally, the risk haplotype AC and the protective haplotype GT, generated by two SNPs in TNKS, were considerably more likely to be association with HM (for AC, P = .002 and OR = 1.26; for GT, P = .027 and OR = 0.84).

Conclusions: Our results demonstrated that some heritable variants in the TNKS gene are associated with HM in the Han population. The possible functions of TNKS in the development and pathogenesis of hereditary high myopia still require further researches to identify.  相似文献   

9.
人工智能引发了医疗领域的数字革命,在推动行业发展方面具有极大潜力。本研究围绕临床诊疗、医学研究和公共卫生三个基本场景,聚焦人工智能与传统中医药的交叉与融合,并着重介绍人工智能在疾病诊断、决策支持、医学研究以及重大公共卫生事件中的应用。虽然人工智能在诸多方面显示出独特优势,但仍存在透明度不高、缺乏安全性评估和相关法律法规监管等问题需要谨慎解决,以促进人工智能技术在医疗领域的推广。  相似文献   
10.
Introduction:Subchromosomal deletions and duplications could currently be detected by noninvasive preliminary screening (NIPS). However, NIPS is a screening test that requires further diagnosis. Here we report a fetus with an autosomal abnormality revealed by NIPS and conventional karyotype combined with copy number variations sequencing (CNV-seq) confirmed the fetus with an unbalanced translocation.Patient concern:This was the fourth pregnancy of a 30-year-old woman who underwent 2 spontaneous abortions and gave birth to a child with a normal phenotype. The woman and her husband were healthy and nonconsanguineous. NIPS indicated a repeat of about 19-Mb fragment at the region of 16q22.1-q22.4 at 17-week gestation.Diagnoses:The combination of traditional karyotype and CNV-seq could better locate the abnormal chromosomal region and further identify the source of fetal chromosomal abnormalities. Simultaneously, we evaluated the fetal morphology by ultrasound examination. The karyotype of the fetus was 46,XX,der(7)t(7;16)(p22;q23) and CNV-seq results showed an approximately 20.96-Mb duplication in 16q22.1-q24.3 (69200001-90160000) and an approximately 3.86-Mb deletion in 7p22.3-p22.2 (40001-3900000). Prenatal ultrasound revealed the fetal micrognathia. The paternal karyotype was 46,XY, t (7;16) (p22;q23), while the maternal was normal. The fetus inherited an abnormal chromosome 7 from its father.Interventions:No treatment for the fetus.Outcomes:Pregnancy was terminated.Conclusions:To our knowledge, the occurrence of de novo partial trisomy 16q (16q22.1-qter) and partial monosomy 7p (7p22.2-pter) has not previously been reported up to now. Here, we present the perinatal findings of such a case and a review of the literatures. CNV-seq combined with karyotype is a useful tool for chromosomal abnormalities indicated by NIPS.  相似文献   
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