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991.
Namhun Lee Se-Jong Oh Jang-Woo Park Kyung-Rok Nam Kyung-Jun Kang Kyo-Chul Lee Yong-Jin Lee June-Seek Choi Jeong-Ho Seok Jae-Yong Choi 《International journal of molecular sciences》2021,22(5)
Early life stress (ELS) is strongly associated with psychiatric disorders such as anxiety, depression, and schizophrenia in adulthood. To date, biological, behavioral, and structural aspects of ELS have been studied extensively, but their functional effects remain unclear. Here, we examined NeuroPET studies of dopaminergic, glutamatergic, and serotonergic systems in ELS animal models. Maternal separation and restraint stress were used to generate single or complex developmental trauma. Body weights of animals exposed to single trauma were similar to those of control animals; however, animals exposed to complex trauma exhibited loss of body weight when compared to controls. In behavioral tests, the complex developmental trauma group exhibited a decrease in time spent in the open arm of the elevated plus-maze and an increase in immobility time in the forced swim test when compared to control animals. In NeuroPET studies, the complex trauma group displayed a reduction in brain uptake values when compared to single trauma and control groups. Of neurotransmitter systems analyzed, the rate of decrease in brain uptake was the highest in the serotonergic group. Collectively, our results indicate that developmental trauma events induce behavioral deficits, including anxiety- and depressive-like phenotypes and dysfunction in neurotransmitter systems. 相似文献
992.
993.
994.
Eugene Choi Sung Jean Park Gunhee Lee Seung Kew Yoon Minho Lee Suk Kyeong Lee 《International journal of molecular sciences》2021,22(6)
Hepatocellular carcinoma (HCC), the most common malignant tumor in the liver, grows and metastasizes rapidly. Despite advances in treatment modalities, the five-year survival rate of HCC remains less than 30%. We sought genetic mutations that may affect the oncogenic properties of HCC, using The Cancer Genome Atlas (TCGA) data analysis. We found that the GNAQ T96S mutation (threonine 96 to serine alteration of the Gαq protein) was present in 12 out of 373 HCC patients (3.2%). To examine the effect of the GNAQ T96S mutation on HCC, we transfected the SK-Hep-1 cell line with the wild-type or the mutant GNAQ T96S expression vector. Transfection with the wild-type GNAQ expression vector enhanced anchorage-independent growth, migration, and the MAPK pathways in the SK-Hep-1 cells compared to control vector transfection. Moreover, cell proliferation, anchorage-independent growth, migration, and the MAPK pathways were further enhanced in the SK-Hep-1 cells transfected with the GNAQ T96S expression vector compared to the wild-type GNAQ-transfected cells. In silico structural analysis shows that the substitution of the GNAQ amino acid threonine 96 with a serine may destabilize the interaction between the regulator of G protein signaling (RGS) protein and GNAQ. This may reduce the inhibitory effect of RGS on GNAQ signaling, enhancing the GNAQ signaling pathway. Single nucleotide polymorphism (SNP) genotyping analysis for Korean HCC patients shows that the GNAQ T96S mutation was found in only one of the 456 patients (0.22%). Our data suggest that the GNAQ T96S hotspot mutation may play an oncogenic role in HCC by potentiating the GNAQ signal transduction pathway. 相似文献
995.
对云南省剑川县、墨江县的600名6 ~ 24个月龄婴幼儿进行膳食及健康调查,评价两地婴幼儿的生长发育情况,为当地卫生机构普及营养知识和少数民族营养支持计划提供数据支持.采用外科体检和膳食营养调查同步进行的方法对剑川白族和墨江县哈尼族6~24月龄婴幼儿膳食摄入状况及身体发育指标进行调查,并与参考文献中的其他地区同龄进行纵向比较,综合评价两地婴幼儿的健康发育状况.两地6~24月龄婴幼儿的营养摄入低于国家推荐量,并且生长发育指标低于城区的婴幼儿,剑川白族婴幼儿发育指标好于墨江哈尼族婴幼儿发育指标.剑川、墨江等地区的婴幼儿营养及身体发育指标偏低,婴幼儿营养摄入和发育状况均堪忧,有必要加强科学指导和管理,并进行营养包支持. 相似文献
996.
莫敏 《湖南工业职业技术学院学报》2021,21(4):108-110,117
"一带一路"倡议对全球经济的影响日渐凸显,国内各行各业实现飞速发展最关键的是强化人才竞争,人才力量不断发展能从根本上提高企业整体竞争力,让企业在全球市场竞争中立于不败之地.本文从"一带一路"背景入手,分析目前装备制造人才培养模式,剖析其中存在的不足,进一步总结我国"一带一路"装备制造人才培养的要点和方法. 相似文献
997.
酒店行业离职率高,提高留职率成为酒店人力资源管理的一大难题.文章对苏锡常地区76家酒店306名员工进行问卷调查,检验心理资本三维度对留职意愿的影响,也检验心理授权在心理资本与酒店员工留职意愿关系中的中介作用.结果表明:心理资本对酒店员工留职意愿有正向影响;心理资本三维度对心理授权三维度有正向影响;心理授权对酒店员工留职意愿有正向影响;心理授权在心理资本与留职意愿的关系中起部分中介作用.因此,从心理资本开发、增强心理授权感知两方面给酒店管理者及员工个人提出建议,以期为酒店提高留职率提供新的管理方向. 相似文献
998.
Zhang Xiaoyan Zhou Chenhe Zhang Jinrong Wang Wenjing Zhang Min Ni Bo Qi Xiwei 《Journal of Electroceramics》2021,47(4):134-140
Journal of Electroceramics - 0.675BiFeO3-0.3BaTiO3-0.025LaFeO3-x mol% Nb2O5 (x?=?0–1.25) multiferroic lead- free ceramics, fabricated by conventional solid-state reaction, were... 相似文献
999.
针对城市道路中车辆密度突变而导致车联网系统的信息冗余和数据丢失等问题,提出了一种基于贪婪转发(GPSR)和距离矢量转发(AODV)的自适应限制性混合路由算法(ARHP),以适应网络环境的高速变化。ARHP将通信网络分为贪婪转发、贪婪-距离矢量转发、距离矢量转发3种模式。通过对有效节点密度和网络状态进行实时评估,可实现转发模式间的切换;通过考察链路质量和端到端的时延性能择优选取邻域节点。采用交通模拟器和离散事件模拟器比较ARHP、AODV和GPSR在改变节点密度或车辆速度时的性能表现,结果表明ARHP在数据包的投递率和端到端的时延性能等方面均优于AODV和GPSR。 相似文献
1000.
Min?-Ho?LeeEmail author Dong?-Joo?Yoon Dae?-Hee?Won Tae?-Sung?Bae Fumio?Watari 《Metals and Materials International》2003,9(1):35-42
In the present study, commercial pure Ti and Ti-6Al-4V alloy specimens with and without alkali and heat treatments were implanted
in the abdominal connective tissue of mice. Conventional stainless steel 316L was also implanted for comparison. After three
months, their biocompatibility was evaluated byin vitro andin vivo experiments. Surface structural changes of specimens due to the alkali treatment and soaking in Hank’s solution were analyzed
by XRD, SEM, XPS and AES. An apatite layer, which accelerates the connection with bone, was formed more easily on the alkali
treated specimens than the non-treated specimens. The number of macrophages, which is known to increase as the inflammatory
reaction proceeds, was much lower for the alkali and heat treated specimens than for the others. The average thickness of
the fibrous capsule formed around the implant was much thinner for the alkali and heat treated specimens than for the others. 相似文献