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排序方式: 共有865条查询结果,搜索用时 15 毫秒
41.
Park YJ Lee YJ Kim SH Joung DS Kim BJ So I Park do J Cho BY 《Molecular and cellular endocrinology》2008,285(1-2):19-25
Ghrelin regulates cell proliferation through the growth hormone secretagogue receptor (GHS-R). We confirmed the expression of GHS-R in FRTL-5 thyroid cells and investigated the effects of ghrelin in thyrocytes using FRTL-5 cells. Ghrelin increased intracellular calcium levels but not intracellular cyclic AMP levels. Ghrelin activated Erk within 2min, then activated Akt and STAT3. Erk phosphorylation was inhibited by the calcium inhibitor cyclopiazonic acid (CPA). Ghrelin alone did not stimulate FRTL-5 cell proliferation but enhanced the effects of thyroid stimulating hormone (TSH). Pretreatment with TSH potentiates the growth effects of ghrelin in thyroid cells, and p66Shc, a growth factor receptor adaptor protein, might mediate these synergistic effects. Ghrelin phosphorylated TSH-induced p66Shc, which was inhibited by CPA. Ghrelin did not affect the proliferation of ARO cells, which showed no increased expression of p66Shc after TSH treatment. Thus, ghrelin-induced intracellular calcium signaling enhanced the TSH-induced proliferation of thyrocytes, possibly mediated by the p66Shc pathway. 相似文献
42.
43.
Samantha L. Kendrick Lucas Redd Andrea Muranyi Leigh A. Henricksen Stacey Stanislaw Lynette M. Smith Anamarija M. Perry Kai Fu Dennis D. Weisenburger Andreas Rosenwald German Ott Randy D. Gascoyne Elaine S. Jaffe Elías Campo Jan Delabie Rita M. Braziel James R. Cook Raymond R. Tubbs Louis M. Staudt Wing Chung Chan Christian Steidl Thomas M. Grogan Lisa M. Rimsza 《Human pathology》2014
44.
《The world journal of biological psychiatry》2013,14(8):583-589
AbstractObjectives. Lower levels of serum brain derived neurotrophic factor (BDNF) is one of the best known biomarkers of depression. To identify genetic variants associated with serum BDNF, we tested the Val66Met (rs6265) functional variant and conducted a genome-wide association scan (GWAS). Methods. In a community-based sample (N = 2054; aged 19–101, M = 51, SD = 15) from Sardinia, Italy, we measured serum BDNF concentration and conducted a GWAS. Results. We estimated the heritability of serum BDNF to be 0.48 from sib-pairs. There was no association between serum BDNF and Val66Met in the SardiNIA sample and in a meta-analysis of published studies (k = 13 studies, total n = 4727, P = 0.92). Although no genome-wide significant associations were identified, some evidence of association was found in the BDNF gene (rs11030102, P = 0.001) and at two loci (rs7170215, P = 4.8 × 10–5 and rs11073742 P = 1.2 × 10–5) near and within NTRK3 gene, a neurotrophic tyrosine kinase receptor. Conclusions. Our study and meta-analysis of the literature indicate that the BDNF Val66Met variant is not associated with serum BDNF, but other variants in the BDNF and NTRK3 genes might regulate the level of serum BDNF. 相似文献
45.
《The world journal of biological psychiatry》2013,14(3):178-187
AbstractObjectives. Converging evidence suggests that the brain-derived neurotrophic factor (BDNF) gene Val66Met polymorphism affects brain structure. Yet the majority of studies have shown no effect of this polymorphism on hippocampal volumes, perhaps due to small effect size. Methods. We performed a meta-analysis of studies investigating the association between Val66Met BDNF polymorphism and hippocampal volumes in healthy subjects by combining standardized differences between means (SDM) from individual studies using random effect models. Results. Data from 399 healthy subjects (255 Val-BDNF homozygotes and 144 carriers of at least one Met-BDNF allele) in seven studies were meta-analysed. Both the left and right hippocampi were significantly larger in Val-BDNF homozygotes than in carriers of at least one Met-BDNF allele (SDM = 0.41, 95% Confidence Interval = 0.20; 0.62, z = 3.86, P = 0.0001; SDM = 0.41; 95% Confidence Interval = 0.20; 0.61, z = 3.81, P = 0.0001, respectively), with no evidence of publication bias. Conclusions. Healthy carriers of BDNF gene Val66Met polymorphism show bilateral hippocampal volume reduction. The effect size was small, but the same direction of effect was seen in all meta-analyzed studies. The association with the BDNF gene Val66Met polymorphism makes hippocampal volume a potential candidate for an endophenotype of disorders presenting with reduced hippocampal volumes. 相似文献
46.
目的 探讨人p66Shc重组腺病毒抑制人宫颈癌Hela细胞增殖的作用及机制.方法 Hela细胞分为空白对照组(不感染腺病毒)、阴性对照组(感染Adeno X-LacZ)和实验组(感染AdenoX-p66Shc).通过细胞生长曲线、MTT检测分析观察细胞的生长状态;DHE染色法检测细胞内活性氧生成;流式细胞仪检测细胞周期;Western Blot法检测细胞内相关蛋白的表达.结果 p66Shc重组腺病毒能够抑制Hela细胞增殖,且随着p66Shc重组腺病毒处理时间延长和剂量增加其抑制作用增强.与空白和阴性对照组比较,p66Shc重组腺病毒感染48 h后,G2/M期细胞比例明显升高,其差异具有统计学意义(P<0.01);同时引起Hela细胞活性氧水平显著上升,p53、CyclinB1蛋白表达显著升高,其差异具有统计学意义(P<0.05).结论 p66Shc重组腺病毒能够显著抑制Hela细胞增殖,并诱导其发生G2/M期阻滞. 相似文献
47.
目的评价新型纳米羟基磷灰石/聚酰胺66融合器(nano-hydroxyapatite/polyamide66Cage,n—HA/PA66Cage)植人人体内可能引起的全身毒性反应及对人体局部组织的影响。方法2012年2月至2012年4月将n—FLA/PA66Cage通过腰椎后路经椎间孔进行腰椎椎体融合植入20例患者体内,通过对研究对象检查术前、术后4d、术后2个月等3个时期的血压、脉搏、体温、免疫球蛋白A、G、M、补体C3、C4、谷丙转氨酶、谷草转氨酶、肌酐、尿素、白细胞、红细胞、血红蛋白、血小板、C反应蛋白、血沉、局部反应等指标。结果n—HA/PA66Cage植人人体后,除了术后4d白细胞、红细胞、血红蛋白、血小板等血常规、C反应蛋白、血沉等检查与术前相比,存在统计学差异(P〈0.05);在不同时相,其他检查结果之间无统计学意义(P〉0.05)。结论新型n—HA/PA66Cage具有良好的生物安全性。 相似文献
48.
Xi Yang Qi Chen Limin Liu Yueming Song Qingquan Kong Jiancheng Zeng Youdi Xue Chunpeng Ren 《International orthopaedics》2013,37(12):2421-2427
Purpose
The titanium mesh cage (TMC) is a typical metal cage device which has been widely used in cervical reconstruction for decades. Nano-hydroxyapatite/polyamide-66 (n-HA/PA66) cage is a novel biomimetic non-metal cage device growing in popularity in many medical centres in recent years. There has been no comparison of the efficacy between these two anterior reconstructing cages. The purpose of this study was to compare the radiographic and clinical outcomes of these two different devices.Methods
Sixty-seven eligible patients with single-level ACCF using TMC or n-HA/PA66 cage for cervical degenerative diseases, with four-year minimum follow-up, were included in this prospective non-randomised comparative study. Their radiographic (cage subsidence, fusion status, segmental sagittal alignment [SSA]) and clinical (VAS and JOA scales) data before surgery and at each follow-up was recorded completely.Results
The fusion rate of the n-HA/PA66 group was higher than TMC at one year after surgery (94 % vs. 84 %) though their finial fusion rates were similar (97 % vs. 94 %). Finial n-HA/PA66 cage subsidence was 1.5 mm with 6 % of severe subsidence over three millimetres, which was significantly lower than the respective 2.9 mm and 22 % of TMC (P < 0.0001). Lastly, SSA, VAS and JOA in TMC group were worse than in the n-HA/PA66 group (P = 0.235, 0.034 and 0.007, respectively).Conclusions
The n-HA/PA66 cage is associated with earlier radiographic fusion, less subsidence and better clinical results than TMC within four years after one-level ACCF. With the added benefit of radiolucency, the n-HA/PA66 cage may be superior to TMC in anterior cervical construction. 相似文献49.
目的探讨弥漫性轴索损伤(DAI)(Ⅱ型)患者伤后1个月血清脑源性神经营养因子(BDNF)水平及其Val66Met基因多态性与认知功能的关系。
方法选取晋江市医院神经外科自2015年8月至2020年8月收治的106例DAI(Ⅱ型)患者为病例组,选择同期来本院体检的105名健康体检者为对照组,采用第二版洛文斯顿作业疗法认知量表(LOTCA)、蒙特利尔评估量表中文版(MoCA)分别评估对照组和病例组伤后1个月时的认知功能;采用酶联免疫吸附试验测定2组研究对象的血清BDNF水平;聚合酶链反应-限制性片段长度多态性分析BDNF Val66Met基因多态性;多元逐步回归法分析病例组整体认知功能与BDNF及BDNF Val66Met基因多态性的相关性。
结果病例组伤后1个月相同基因亚型血清BDNF浓度均低于对照组,差异有统计学意义(P<0.05);病例组Val/Val亚型血清BDNF浓度高于Val/Met、Met/Met亚型,差异有统计学意义(P<0.05),而Val/Met和Met/Met亚型血清BDNF浓度比较差异无统计学意义(P>0.05)。病例组患者3种基因亚型伤后1个月的LOTCA和MoCA评分均低于对照组,差异有统计学意义(P<0.05);病例组Val/Val亚型评分高于Val/Met、Met/Met评分,差异有统计学意义(P<0.05),而Val/Met和Met/Met亚型评分比较,差异无统计学意义(P>0.05)。DAI(Ⅱ型)整体认知水平与BDNF Val66Met基因多态性、BDNF浓度具有线性回归关系(F=11.417,P<0.001),其具有一定的相关性(|β|=0.966、0.877;r=0.569、0.579)。
结论BDNF可影响DAI认知功能,其BDNF Val66Met基因多态性可能是影响DAI认知功能的风险因素之一。 相似文献
50.
目的总结后交叉韧带(posterior cruciate ligament,PCL)重建中转角效应的研究进展。方法查阅近年来国内外 PCL 重建中转角效应相关研究,并进行总结。结果研究表明转角效应是导致 PCL 重建术后移植物松弛的主要原因。目前临床上主要通过改变骨隧道固定方式、改变骨隧道方位以及挤压螺钉辅助固定、保留韧带残端、打磨骨隧道口骨质等方式来减小该效应,但缺乏长期临床随访结果。结论针对转角效应的改进方法仍存在较大争议,需要更深入的基础研究,进一步探索重建后 PCL 磨损机制。 相似文献