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991.
Guan‐Yu Liang Rui Qin Jing Li Guan‐Xiang Liang Yong‐Juan Guan Zhan‐Hui Gao 《Pediatrics international》2011,53(4):541-545
Background: The optimal serum level of 25‐hydroxyvitamin D (25‐(OH)D) for bone health is still unclear, especially in children. Hypovitaminosis D is also re‐emerging in developed and developing countries. The purpose of the present study was therefore to determine optimal serum 25‐(OH)D level and preliminarily identify the vitamin D nutritional status in Nanjing children. Methods: All subjects (76 healthy, 66 suffering from infectious diseases) aged 0–10 years were recruited during the period December 2007–March 2008. Venous blood samples were collected before breakfast and the levels of serum 25‐(OH)D, parathyroid hormone (PTH), bone‐specific alkaline phosphatase (BAP), calcium (Ca), phosphorus (P) were determined. The optimal level of serum 25‐(OH)D was explored using the three response curves of 25‐(OH)D versus PTH, 25‐(OH)D versus BAP, and 25‐(OH)D versus Ca×P product. Results: For 25‐(OH)D ≤ 50 nmol/L, PTH and BAP were both inversely correlated with 25‐(OH)D (PTH, r=?0.864, P < 0.01; BAP, r=?0.856, P < 0.01). For 25‐(OH)D > 50–60 nmol/L, levels of PTH and BAP remained steady. With regard to the Ca×P product, for 25‐(OH)D ≤ 50 nmol/L, Ca×P product increased as 25‐(OH)D increased (r= 0.037, P > 0.05). For 25‐(OH)D > 50–60 nmol/L, Ca×P product remained steady. The mean serum level of 25‐(OH)D was 80.5 ± 29.3 nmol/L (mean ± SD) in the healthy children, and 65.7 ± 32.3 nmol/L in the sick children. Conclusion: The optimal 25‐(OH)D level may be 50–60 nmol/L for bone health in Nanjing children. The vitamin D nutritional status of Nanjing children is relatively good in winter. 相似文献
992.
目的 分析学龄前听障儿童助听后言语流畅性的特征,探讨辅听装置、年龄、性别、语训时长对其言语流畅性的影响.方法 以109例3.5~6.5岁学龄前健听及听障儿童为研究对象,其中健听儿童30例(健听组),双耳佩戴助听器的听障儿童28例(助听器组),右耳植入人工耳蜗的听障儿童26例(人工耳蜗组),同时佩戴助听器和人工耳蜗双耳双模式助听的听障儿童25例(双模式组),通过主题对话的形式分别采集各组儿童的语音样本,比较各组儿童在自发性言语语言任务下的语速、停顿、重复和拖延差异;分析辅听装置、年龄、性别、语训时长等因素对听障儿童言语流畅性的影响.结果 ①健听组儿童的语速显著高于其他三组(P<0.05),健听组停顿次数显著低于人工耳蜗组(P=0.001)和双模式组(P=0.032);健听组拖延次数显著低于助听器组(P=0.001)和双模式组(P=0.001),极显著低于人工耳蜗组(P<0.001);②不同性别听障儿童语速、停顿、重复次数和拖延次数差异无统计学意义(P>0.05),而助听器组语速显著高于人工耳蜗组(P=0.045),人工耳蜗组停顿次数显著高于助听器组(P=0.028);3.5~5岁听障儿童语速显著低于5.1~6.5岁组(P=0.042);语训0~2.5年听障儿童语速显著低于语训>2.5年者(P=0.002),停顿及重复次数均高于语训>2.5年者(分别P=0.047,P=0.02).结论 听障儿童的语速低于健听儿童,停顿次数、拖延次数高于健听儿童;年龄、辅听装置、语训时长影响学龄前听障儿童的言语流畅性,性别影响不大. 相似文献
993.
食管鳞状细胞癌是世界上最常见的癌症之一,转移快、预后差、死亡人数多。其中主要的死亡原因之一是转移。转移是由一系列细胞信号通路多方面共同作用的过程。长非编码RNA(lncRNAs)作为转录调控因子,可以调控多种基因组过程和细胞过程,如细胞增殖、迁移和侵袭等。lncRNAs也被证明参与/调节与肿瘤转移相关的信号通路。因此,它们在分子肿瘤学研究中越来越受关注。许多研究人员试图揭示lncRNAs在食管癌发生和转移中的生物学和临床相关性,包括诊断、预后和治疗反应。本文就lncRNAs在食管癌转移中的生物学作用以及转移相关的lncRNAs在肿瘤诊断和预后中的临床意义作一综述。 相似文献
994.
Fang Bian Xiaoyan Yang Fan Zhou Pin-Hui Wu Shasha Xing Gao Xu Wenjing Li Jiangyang Chi Changhan Ouyang Yonghui Zhang Bin Xiong Yongsheng Li Tao Zheng Dan Wu Xiaoqian Chen Si Jin 《British journal of pharmacology》2014,171(10):2671-2684
Background and Purpose
The retention of plasma low-density lipoprotein (LDL) particles in subendothelial space following transcytosis across the endothelium is the initial step of atherosclerosis. Whether or not C-reactive protein (CRP) can directly affect the transcytosis of LDL is not clear. Here we have examined the effect of CRP on transcytosis of LDL across endothelial cells and have explored the underlying mechanisms.Experimental Approach
Effects of CRP on transcytosis of FITC-labelled LDL were examined with human umbilical vein endothelial cells and venous rings in vitro and, in vivo, ApoE-/- mice. Laser scanning confocal microscopy, immunohistochemistry and Oil Red O staining were used to assay LDL.Key Results
CRP increased transcytosis of LDL. An NADPH oxidase inhibitor, diphenylene iodonium, and the reducing agent, dithiothreitol partly or completely blocked CRP-stimulated increase of LDL transcytosis. The PKC inhibitor, bisindolylmaleimide I and the Src kinase inhibitor, PP2, blocked the trafficking of the molecules responsible for transcytosis. Confocal imaging analysis revealed that CRP stimulated LDL uptake by endothelial cells and vessel walls. In ApoE-/- mice, CRP significantly promoted early changes of atherosclerosis, which were blocked by inhibitors of transcytosis.Conclusions and Implications
CRP promoted atherosclerosis by directly increasing the transcytosis of LDL across endothelial cells and increasing LDL retention in vascular walls. These actions of CRP were associated with generation of reactive oxygen species, activation of PKC and Src, and translocation of caveolar or soluble forms of the N-ethylmaleimide-sensitive factor attachment protein. 相似文献995.
996.
997.
近年来,消化内镜技术不断发展,在消化道疾病诊治方面发挥着越来越重要的作用。其中,隧道内镜技术(tunnel endoscopy,TE)是在内镜黏膜下剥离术和经自然腔道内镜手术基础上发展而来的一项技术。TE拓展了消化内镜治疗的适应证,为很多疾病的治疗提供了新的方式,本文就TE临床应用进展做一综述。 相似文献
998.
Xinlu Gao Hanjing Li Xiuxiu Wang Zhongyu Ren Yanan Tian Jingxuan Zhao Wenyi Qi Hongbo Wang Ying Yu Rui Gong Hongyang Chen Haoyu Ji Fan Yang Wenya Ma Yu Liu 《International journal of medical sciences》2022,19(8):1254
Mammalian cardiomyocytes (CMs) maintain a low capacity for self-renewal in adulthood, therefore the induction of CMs cycle re-entry is an important approach to promote myocardial repair after injury. Recently, photobiomodulation (PBM) has been used to manipulate physiological activities of various tissues and organs by non-invasive means. Here, we demonstrate that conditioned PBM using light-emitting diodes with a wavelength of 630 nm (LED-Red) was capable of promoting the proliferation of neonatal CMs. Further studies showed that low-power LED-Red affected the expression of miR-877-3p and promoted the proliferation of CMs. In contrast, silencing of miR-877-3p partially abolished the pro-proliferative actions of LED-Red irradiation on CMs. Mechanistically, GADD45g was identified as a downstream target gene of miR-877-3p. Conditioned LED-Red irradiation also inhibited the expression of GADD45g in neonatal CMs. Moreover, GADD45g siRNA reversed the positive effect of LED-Red on the proliferation of neonatal CMs. Taken together, conditioned LED-Red irradiation increased miR-877-3p expression and promoted the proliferation of neonatal CMs by targeting GADD45g. This finding provides a new insight into the role of LED-Red irradiation in neonatal CMs biology and suggests its potential application in myocardial injury repair. 相似文献
999.
Pin Xu Kazuhiro Shimomura Changhoon Lee Xiaofei Gao Eleanor H. Simpson Guocun Huang Chryshanthi M. Joseph Vivek Kumar Woo-Ping Ge Karen S. Pawlowski Mitchell D. Frye Saïd Kourrich Eric R. Kandel Joseph S. Takahashi 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(31)
1000.
本文对药材藁本及其常见混伪品的rDNA ITS2进行了PCR扩增、测序,并运用MEGA软件对该区进行序列分析,比较了ITS2碱基序列的差异及其规律,同时为药材藁本及混伪品的指纹图谱鉴别提供分子标记.结果显示辽藁本的种内差异较小,而与其主要混伪品间存在较大的变异,差异性范围为5.7%~35.3%.根据ITS2序列特征构建的系统树,药材藁本的样品紧密的聚在一起,和其混伪品可以明确区分,支持率为100%.此外,ITS2的二级结构可作为鉴定药材藁本及混伪品种的一个方法,具有一定的系统学及分类学意义.本研究表明rDNA ITS2序列分析可作为药材藁本与混伪品的一种有效的分子鉴定方法,具有重要的应用价值. 相似文献