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51.
本文报道产前超声诊断胎儿右房异构一例。孕妇孕24周产前超声检查发现胎儿左位心合并复杂心血管畸形(右心室双出口、房室间隔缺损、肺动脉发育不良、双侧上腔静脉、心下型完全型肺静脉异位引流)、胃泡位于腹腔右侧、中位肝、可疑无脾、腹主动脉与下腔静脉位于脊柱左侧、双侧支气管呈右侧支气管对称形态,综合考虑右房异构可能。引产后经尸体解剖证实脾脏发育不良、右房异构。右房异构常合并复杂心血管畸形,因此产前超声发现复杂心血管畸形时,应警惕右房异构的可能。右房异构病死率极高,产前诊断具有重要意义。 相似文献
52.
Growth Hormone Induces Recurrence of Infantile Hemangiomas After Apparent Involution: Evidence of Growth Hormone Receptors in Infantile Hemangioma 下载免费PDF全文
Naikhoba C. O. Munabi B.A. Qian Kun Tan H.S. Maria C. Garzon M.D. Gerald G. Behr M.D. Carrie J. Shawber Ph.D. June K. Wu M.D. 《Pediatric dermatology》2015,32(4):539-543
Infantile hemangiomas (IHs) are the most common benign tumor of infancy, characterized by a natural history of early proliferation in the first months of life to eventual involution during childhood, often with residual fibrofatty tissue. Once involution has been achieved, IHs do not typically recur. We present two cases of exogenous growth hormone therapy resulting in the recurrence of IHs in late childhood, supported by radiological, immunohistochemical, in vitro, and in vivo evidence. 相似文献
53.
肠易激综合征(Irritable bowel syndrome,IBS)是临床常见病、多发病,其治疗方法丰富,但部分患者疗效欠佳,发展成难治性IBS。目前国内外关于针灸治疗难治性IBS的临床随机对照试验尚不多见。本文立足试验方案设计的“PICOS”原则,从研究对象及诊断标准、干预措施、对照措施、结局指标四个方面入手,重点探讨针刺辅助治疗难治性肠易激综合征临床试验设计的关键要点。从选择特色优势病种、明确诊断标准、制定符合临床实际的干预方案、运用符合目标的安慰针刺、结合研究设计和目的选定结局指标几个角度,阐述试验相关环节设计的原因和思考。 相似文献
54.
Lesley A. Inker Morgan E. Grams Andrew S. Levey Josef Coresh Massimo Cirillo John F. Collins Ron T. Gansevoort Orlando M. Gutierrez Takayuki Hamano Gunnar H. Heine Shizukiyo Ishikawa Sun Ha Jee Florian Kronenberg Martin J. Landray Katsuyuki Miura Girish N. Nadkarni Carmen A. Peralta Dietrich Rothenbacher Mark Woodward 《American journal of kidney diseases》2019,73(2):206-217
55.
Hae June Lee Yeonghoon Son Minyoung Lee Changjong Moon Sung Ho Kim In Sik Shin Miyoung Yang Sangwoo Bae Joong Sun Kim 《中国神经再生研究》2019,(9)
Sodium butyrate is a histone deacetylase inhibitor that affects various types of brain damages. To investigate the effects of sodium butyrate on hippocampal dysfunction that occurs after whole-brain irradiation in animal models and the effect of sodium butyrate on radiation exposure-induced cognitive impairments,adult C57BL/6 mice were intraperitoneally treated with 0.6 g/kg sodium butyrate before exposure to 10 Gy cranial irradiation. Cognitive impairment in adult C57BL/6 mice was evaluated via an object recognition test 30 days after irradiation. We also detected the expression levels of neurogenic cell markers(doublecortin)and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor. Radiation-exposed mice had decreased cognitive function and hippocampal doublecortin and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. Sodium butyrate pretreatment reversed these changes. These findings suggest that sodium butyrate can improve radiation-induced cognitive dysfunction through inhibiting the decrease in hippocampal phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. The study procedures were approved by the Institutional Animal Care and Use Committee of Korea Institute of Radiological Medical Sciences(approval No. KIRAMS16-0002) on December 30, 2016. 相似文献
56.
Mengdie Jiang Bihan Wu Yongbing Sun Yanhuai Ding Yixi Xie 《Toxicology mechanisms and methods》2019,29(4):291-299
In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA. 相似文献
57.
目的:探讨异柠檬酸脱氢酶-1(IDH1)和端粒酶逆转录酶(TERT)启动子突变对高级别胶质瘤患者的预后价值。方法:选取2014年9月至2017年6月于我院行手术切除且术后病理提示为高级别胶质瘤的患者63例(WHO Ⅲ级27例,Ⅳ级36例),完善临床资料、随访资料、分子检测结果。应用Sanger测序法检测样本中IDH1和TERT启动子突变情况,根据结果将患者分为不同亚组,通过比较其生存期的差异,分析基因突变与患者预后的关系。结果:63例高级别胶质瘤中,IDH1突变型和野生型患者的中位生存期分别为24和10个月,差异有统计学意义(P<0.01);TERT突变型和野生型的中位生存期无明显差异(P>0.05)。IDH1突变为高级别胶质瘤患者预后良好的因素,TERT突变不能单独提示预后,二者联合分析提示:IDH1突变/TERT突变组预后最好,IDH1野生/TERT突变组预后最差,IDH1突变/TERT野生组预后稍好于IDH1野生/TERT野生组,四组间预后有明显差异。结论:IDH1突变的高级别胶质瘤患者有较好的临床预后,在此基础上,TERT启动子突变检测有助于进一步划分其预后分层。 相似文献
58.
以培养创新型人才为目标,大连医科大学制定实施了“5+3”创新人才培养改革方案,以导师制培养为载体,在医学本科教育全过程中,制定分阶段创新能力培养体系,涵盖课程、讲座、实验设计、论文等基本科研能力训练,强化本科生科研能力培养。通过对首届“5+3”学生阶段性培养成果的统计学分析发现,“5+3”学生发表中文期刊、SCI,主持国家级创新项目、省级创新项目的比例均显著高于普通5年制学生,差异具有统计学意义(P<0.05)。虽然实施过程中存在一些问题和不足,但以导师制为核心的科研基础训练对提高学生科研思维和创新能力效果显著,对培养医学创新型人才具有可实施性。 相似文献
59.
60.
Quantitative chemical exchange saturation transfer (qCEST) MRI – omega plot analysis of RF‐spillover‐corrected inverse CEST ratio asymmetry for simultaneous determination of labile proton ratio and exchange rate 下载免费PDF全文
Renhua Wu Gang Xiao Iris Yuwen Zhou Chongzhao Ran Phillip Zhe Sun 《NMR in biomedicine》2015,28(3):376-383
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献