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The Role of Brain-derived Neurotrophic Factor in Mouse Oocyte Maturation in vitro 被引量:1
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作者 张玲 李洁 +1 位作者 苏萍 熊承良 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第6期781-785,共5页
Brain-derived neurotrophic factor (BDNF) can promote developmental competence in mammalian oocytes during in vitro maturation (IVM),but the role of BDNF in oocyte maturation at cellular level is not still clear.In thi... Brain-derived neurotrophic factor (BDNF) can promote developmental competence in mammalian oocytes during in vitro maturation (IVM),but the role of BDNF in oocyte maturation at cellular level is not still clear.In this study,mouse cumulus-enclosed oocytes subjected to IVM were fertilized and cultured to blastocyst stage.Meiotic spindle configuration and cortical granules distribution during oocyte maturation in vitro were assessed by using immunofluorescence and laser confocal microscopy.The results showed that BDNF contributed to the complete preimplantation development of mouse oocytes compared to the control oocytes (13.78% vs.5.92%;P【0.05).Further,BDNF did not accelerate nuclear maturation of IVM oocytes.For the BDNF-treated oocytes at meiosis Ⅰ,Meiotic spindle areas were significantly smaller and the number of cytoplasmic microtubule organizing centers was greater than that in the control,and the percentages of oocytes showed spindles positioned near the oolemma and a well-formed cortical granule-free domain were significantly higher than that of the control.These morphological characteristics of the BDNF-treated oocytes were much closer to the oocytes matured in vivo than those of the control oocytes.In conclusion,BDNF can promote the developmental competence of mouse IVM oocytes,by improving the meiotic spindle configuration and location and cortical granules distribution at meiosis Ⅰ. 展开更多
关键词 brain-derived neurotrophic factor OOCYTE in vitro maturation meiotic spindle cortical granule
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Impaired pericyte-Müller glia interaction via PDGFRβ suppression aggravates photoreceptor loss in a rodent model of light-induced retinal injury
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作者 Wei Xu Li-Jin Cui +3 位作者 Xiao-Ying Yang Xiao-Yuan Cui Jian Guo Guo-Xing Xu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1800-1808,共9页
AIM:To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptorβ(PDGFRβ)signaling pathway in r... AIM:To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptorβ(PDGFRβ)signaling pathway in retinal pericytes on photoreceptor loss and Müller glial response.METHODS:Sprague-Dawley rats were exposed to intense light to induce retinal injury.Neutralizing antibody against PDGFRβwere deployed to block the signaling pathway in retinal pericytes through intravitreal injection.Retinal histology and Müller glial reaction were assessed following light injury.In vitro,normal and PDGFRβ-blocked retinal pericytes were cocultured with Müller cell line(rMC-1)to examine morphological and protein expression changes upon supplementation with light-injured supernatants of homogenized retinas(SHRs).RESULTS:PDGFRβblockage 24h prior to intense light exposure resulted in a significant exacerbation of photoreceptor loss.The upregulation of GFAP and p-STAT3,observed after intense light exposure,was significantly inhibited in the PDGFRβblockage group.Fur ther upregulation of cytokines monocyte chemoattractant protein 1(MCP-1)and interleukin-1β(IL-1β)was also observed following PDGFRβinhibition.In the in vitro coculture system,the addition of light-injured SHRs induced pericyte deformation and upregulation of proliferating cell nuclear antigen(PCNA)expression,while Müller cells exhibited neuron-like morphology and expressed Nestin.However,PDGFRβblockage in retinal pericytes abolished these cellular responses to light-induced damage,consistent with the in vivo PDGFRβblockage findings.CONCLUSION:Pericyte-Müller glia interaction plays a potential role in the endogenous repair process of retinal injury.Impairment of this interaction exacerbates photoreceptor degeneration in light-induced retinal injury. 展开更多
关键词 PERICYTE Müller glia light-induced retinal injury platelet-derived growth factor receptorβ signal pathway
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Effects of vascular endothelial growth factor supplementation and alginate embedding on human oocyte maturation in vitro
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作者 Farhang Abed Morteza Fallah-Karkan +3 位作者 Masoumeh Majidi Zolbin Pegah Naghizadeh Fereshte Aliakbari Hossein Yazdekhasti 《Asian pacific Journal of Reproduction》 2020年第3期129-134,共6页
Objective:To evaluate whether the use of vascular endothelial growth factor(VEGF)with alginate increases oocyte maturation following in vitro maturation.Methods:This experimental study was performed on 150 immature oo... Objective:To evaluate whether the use of vascular endothelial growth factor(VEGF)with alginate increases oocyte maturation following in vitro maturation.Methods:This experimental study was performed on 150 immature oocytes(germinal vesicle oocytes)from females who were candidates for assisted reproductive technology.The germinal vesicle oocytes were randomly placed in the control,alginate,and VEGF plus alginate groups.The basic culture medium for oocytes culture(tissue culture medium 199,follicle-stimulating hormone 0.075 IU/mL,and fetal bovine serum 10%)was used in the control,alginate,and VEGF plus alginate groups.For the treatment groups(alginate,and VEGF plus alginate groups),alginate(8%)and VEGF(5 ng/mL)were added to the basic culture medium.After culture,immature oocytes were considered as oocytes unchanged in the nucleus whereas oocytes with a polar body were considered as mature oocytes(metaphaseⅡstage).The mature oocytes in each group were fertilized by intracytoplasmic sperm injection and formed embryos were evaluated by reverse microscope.Results:The oocyte maturation rate(metaphaseⅡ)significantly(P<0.05)increased in the alginate plus VEGF group as compared with the alginate alone and control groups during in vitro maturation.On day 2,the cleavage rates were significantly different in the matured oocytes between the treatment groups and the control group.The percentage of the two-cell stage,four-cell stage and eight-cell embryos was significantly higher in the treatment groups compared with the control group(P<0.05).Conclusions:Supplementation of VEGF with alginate can improve oocyte maturation in culture media.VEGF with alginate may promote the quality of nuclear and cytoplasmic maturation of human oocytes in vitro. 展开更多
关键词 ALGINATE INFERTILITY Human OOCYTE maturation Vascular ENDOTHELIAL growth factor
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Expression of nerve growth factor precursor, mature nerve growth factor and their receptors during cerebral ischemia-reperfusion injury 被引量:3
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作者 Guoqian He Jian Guo +4 位作者 Jiachuan Duan Wenming Xu Ning Chen Hongxia Li Li He 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第22期1701-1708,共8页
We investigated nerve growth factor precursor (proNGF) and mature NGF expression in ischemic and non-ischemic cortices after cerebral ischemia-reperfusion injury. In both ischemic and non-ischemic cortices, proNGF w... We investigated nerve growth factor precursor (proNGF) and mature NGF expression in ischemic and non-ischemic cortices after cerebral ischemia-reperfusion injury. In both ischemic and non-ischemic cortices, proNGF was found to be present in the extracellular space and cytoplasm. In addition, mature NGF was expressed in extracellular space, but with a very low signal. In ischemic cortex only, proNGF was significantly decreased, reaching a minimal level at 1 day. Mature NGF was increased at 4 hours, then reached a minimal level at 3 days. The p75 neurotrophin receptor (p75NTR) was significantly decreased after ischemia, and increased at 3 days after ischemia. These results confirmed that proNGF was the predominant form of NGF during the pathological process of cerebral ischemia-repeffusion injury. In addition, our findings suggest that ischemic injury may influence the conversion of proNGF to mature NGF, and that proNGF/p75NTR may be involved in reperfusion injury. 展开更多
关键词 cerebral ischemia-reperfusion injury nerve growth factor precursor mature nerve growth factor p75 neurotrophin receptor cell apoptosis
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Enteric glia mediate neuronal outgrowth through release of neurotrophic factors 被引量:2
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作者 Christopher R. Hansebout Kiran Reddy +1 位作者 Donald Zhang Michel P. Rathbone 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第28期2165-2175,共11页
Previous studies have shown that transplanted enteric glia enhance axonal regeneration, reduce tissue damage, and promote functional recovery following spinal cord injury. However, the mechanisms by which enteric glia... Previous studies have shown that transplanted enteric glia enhance axonal regeneration, reduce tissue damage, and promote functional recovery following spinal cord injury. However, the mechanisms by which enteric glia mediate these beneficial effects are unknown. Neurotrophic factors can promote neuronal differentiation, survival and neurite extension. We hypothesized that enteric glia may exert their protective effects against spinal cord injury partially through the secretion of neurotrophic factors. In the present study, we demonstrated that primary enteric glia cells release nerve growth factor, brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor over time with their concentrations reaching approximately 250, 100 and 50 pg/mL of culture medium respectively after 48 hours. The biological relevance of this secretion was assessed by incubating dissociated dorsal root ganglion neuronal cultures in enteric glia-conditioned medium with and/or without neutralizing antibodies to each of these proteins and evaluating the differences in neurite growth. We discovered that conditioned medium enhances neurite outgrowth in dorsal root ganglion neurons. Even though there was no detectable amount of neurotrophin-3 secretion using ELISA analysis, the neurite outgrowth effect can be attenuated by the antibody-mediated neutralization of each of the aforementioned neurotrophic factors. Therefore, enteric glia secrete nerve growth factor, brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor and neurotrophin-3 into their surrounding environment in concentrations that can cause a biological effect. 展开更多
关键词 spinal cord injury dorsal root ganglia enteric glia neurotrophic factor neurite outgrowth regeneration cell culture IMMUNOHISTOCHEMISTRY central nervous system NEUROREGENERATION
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EXPRESSING HUMAN MATURED BRAIN-DERIVED NEUROTROPHIC FACTOR GENE IN E.Coli AND DETERMINING ITS BIOACTIVITY 被引量:1
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作者 马东亮 任惠民 +3 位作者 胡海涛 刘勇 杨广笑 王全颖 《Academic Journal of Xi'an Jiaotong University》 2001年第1期9-12,共4页
Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expr... Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expression vector plasmid pBV220. The ligation products were used to transform the competent E. Coli DH5a. The proteins or mBDNF were experessed by temperature inducing. The expression products were dealed with solubilizing inclusion bodies and refolding protein. It was introduced into the embryonic chicken DRG to test whether the expressed mBDNF is a biologically active protein. Results The recombinant plasmid pBV/mBDNF was success- fully constructed. By temperature inducing, under the control of the bacteriophage λPL promoter, the experessed mBDNF protein was a 14Kd non-fusion protein,which existed in E. Coli as inclusion bodies. The size or expressed mBDNF is identical to the prediction. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of embryonic 8-day-old chicken DRG neurons as compared to control. Conclusion Tke mBDNF gene can be expressed bioactively in E. Coli. 展开更多
关键词 human matured brain-derived neurotrophic factor (mBDNF) molecular subcloning EXPRESSION bioactivity
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Microglial depletion impairs glial scar formation and aggravates inflammation partly by inhibiting STAT3 phosphorylation in astrocytes after spinal cord injury 被引量:10
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作者 Zhi-Lai Zhou Huan Xie +4 位作者 Xiao-Bo Tian Hua-Li Xu Wei Li Shun Yao Hui Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1325-1331,共7页
Astrocytes and microglia play an orchestrated role following spinal cord injury;however,the molecular mechanisms through which microglia regulate astrocytes after spinal cord injury are not yet fully understood.Herein... Astrocytes and microglia play an orchestrated role following spinal cord injury;however,the molecular mechanisms through which microglia regulate astrocytes after spinal cord injury are not yet fully understood.Herein,microglia were pharmacologically depleted and the effects on the astrocytic response were examined.We further explored the potential mechanisms involving the signal transducers and activators of transcription 3(STAT3)pathway.For in vivo experiments,we constructed a contusion spinal cord injury model in C57BL/6 mice.To deplete microglia,all mice were treated with colony-stimulating factor 1 receptor inhibitor PLX3397,starting 2 weeks prior to surgery until they were sacrificed.Cell proliferation was examined by 5-ethynyl-2-deoxyuridine(EdU)and three pivotal inflammatory cytokines were detected by a specific Bio-Plex Pro^(TM) Reagent Kit.Locomotor function,neuroinflammation,astrocyte activation and phosphorylated STAT3(pSTAT3,a maker of activation of STAT3 signaling)levels were determined.For in vitro experiments,a microglia and astrocyte coculture system was established,and the small molecule STA21,which blocks STAT3 activation,was applied to investigate whether STAT3 signaling is involved in mediating astrocyte proliferation induced by microglia.PLX3397 administration disrupted glial scar formation,increased inflammatory spillover,induced diffuse tissue damage and impaired functional recovery after spinal cord injury.Microglial depletion markedly reduced EdU+proliferating cells,especially proliferating astrocytes at 7 days after spinal cord injury.RNA sequencing analysis showed that the JAK/STAT3 pathway was downregulated in mice treated with PLX3397.Double immunofluorescence staining confirmed that PLX3397 significantly decreased STAT3 expression in astrocytes.Importantly,in vitro coculture of astrocytes and microglia showed that microglia-induced astrocyte proliferation was abolished by STA21 administration.These findings suggest that microglial depletion impaired astrocyte proliferation and astrocytic scar formation,and induced inflammatory diffusion partly by inhibiting STAT3 phosphorylation in astrocytes following spinal cord injury. 展开更多
关键词 ASTROCYTES COCULTURE colony-stimulating factor 1 receptor inhibitor EdU glia scar inflammatory response microglia PHOSPHORYLATION proliferation spinal cord injury STAT3
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转录因子HNF1α基因c.493T>C位点突变对其蛋白质水平的影响
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作者 梁淑杰 彭乙华 +3 位作者 雷佳红 贾艾敏 蒋红 蔡燕 《遗传》 CAS CSCD 北大核心 2024年第3期256-262,共7页
肝细胞核因子1α(hepatocyte nuclear factor 1α,HNF1α)作为一种转录因子在维持胰腺β细胞功能、肝脏脂质代谢等过程中发挥着重要的调控作用。该基因突变是导致青少年起病的成人型糖尿病(maturity onset diabetes of the young,MODY)... 肝细胞核因子1α(hepatocyte nuclear factor 1α,HNF1α)作为一种转录因子在维持胰腺β细胞功能、肝脏脂质代谢等过程中发挥着重要的调控作用。该基因突变是导致青少年起病的成人型糖尿病(maturity onset diabetes of the young,MODY)3型的致病原因,目前已报道的该基因的突变位点众多,如P291fsinsC、P112L等常见的突变位点,但其具体的分子机制尚不清楚。本研究对前期工作中发现的1例携带有HNF1α基因c.493T>C位点突变的MODY3患者,通过应用Mutation Surveyor软件分析突变位点的致病性,构建HNF1α野生型和突变型真核表达质粒,采用Western blot检测两种质粒表达的HNF1α蛋白质的量和稳定性变化,结果发现Mutation Surveyor软件分析提示c.493T>C位点突变可能为致病性变异基因,Western blot显示突变型真核质粒表达的HNF1α蛋白质的量和稳定性均明显降低,差异均具有统计学意义(P<0.05)。上述结果表明c.493T>C(p.Trp165Arg)变异显著影响HNF1α的表达量及稳定性,可能为其导致疾病发生的原因,为后续深入探究MODY3的分子致病机制提供了新的方向。 展开更多
关键词 MODY HNF1α 基因突变
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胶质细胞内SNARE复合体功能及其与抑郁障碍发生的关系
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作者 谷涓华 焦扬 +1 位作者 鲁琳 王琳琳 《上海交通大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期653-657,共5页
抑郁障碍是现代人类致残和死亡的一个常见原因,部分患者对现有的抗抑郁障碍药物并不敏感,复发率极高。现有的抗抑郁障碍药物存在许多问题,迫切需要找到一种针对多个靶点的新型抗抑郁药。近年来的研究发现,可溶性N-乙基马来酰亚胺敏感因... 抑郁障碍是现代人类致残和死亡的一个常见原因,部分患者对现有的抗抑郁障碍药物并不敏感,复发率极高。现有的抗抑郁障碍药物存在许多问题,迫切需要找到一种针对多个靶点的新型抗抑郁药。近年来的研究发现,可溶性N-乙基马来酰亚胺敏感因子附着蛋白受体(soluble N-ethylmaleimide-sensitive factor attachment protein receptor,SNARE)复合体与抑郁障碍发生及进展密切相关。该文总结和归纳了胶质细胞内SNARE复合体在抑郁障碍发生过程中的潜在作用机制,并对相关研究进行综述,以期为临床上开发新型的抗抑郁障碍药物提供新的思路。 展开更多
关键词 抑郁障碍 可溶性N-乙基马来酰亚胺敏感因子附着蛋白受体复合体 胶质细胞
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CSF1R基因突变致ALSP发病研究进展
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作者 黄正平 江佳薇 +5 位作者 刘淑芬 叶小芳 李弥弥 庄建龙 叶励超 陈春暖 《中国神经精神疾病杂志》 CAS CSCD 北大核心 2024年第3期173-178,共6页
成人发病的白质脑病合并轴索球样变和色素性胶质细胞(adult-onset leukoencephalopathy with axonal spheroids and pigmented glia,ALSP)是临床罕见的常染色体显性遗传病,其具体的发病机制目前还未明确。集落刺激因子1受体(colony-stim... 成人发病的白质脑病合并轴索球样变和色素性胶质细胞(adult-onset leukoencephalopathy with axonal spheroids and pigmented glia,ALSP)是临床罕见的常染色体显性遗传病,其具体的发病机制目前还未明确。集落刺激因子1受体(colony-stimulating factor 1 receptor,CSF1R)是一种细胞表面跨膜酪氨酸激酶受体,与其相关的编码基因突变已被证实是ALSP的潜在致病因素。然而,目前关于CSF1R基因突变致使ALSP发病的具体机制尚不清楚。本文回顾CSF1R基因在ALSP发病过程中的突变位点及致病机制研究,发现CSF1R突变可以通过显性负性效应、功能丧失、单倍体剂量不足及功能获得等机制导致小胶质细胞功能异常,进而引起ALSP的发病。对ALSP病因的深入认识有助于更好地探索潜在的治疗方法。 展开更多
关键词 成人发病的白质脑病合并轴索球样变和色素性胶质细胞 脑白质病变 集落刺激因子1受体 遗传性疾病 小胶质细胞 突变
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不同熟期油菜品种籽粒脱水与气象因子的关系
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作者 易荣 黄晨芳 +4 位作者 贺璐阳 巩若琳 张杏燕 胡继宏 董军刚 《中国农业气象》 CSCD 2024年第8期882-893,共12页
选用中早熟(‘华秦油971’和‘秦油1719’)和中晚熟(‘陕油21’和‘陕油28’)油菜品种,利用Logistic power模型拟合2019−2020年4个油菜品种授粉-收获期≥0℃活动积温与籽粒含水率,分析气象因子对不同熟期油菜品种籽粒含水率的影响。结... 选用中早熟(‘华秦油971’和‘秦油1719’)和中晚熟(‘陕油21’和‘陕油28’)油菜品种,利用Logistic power模型拟合2019−2020年4个油菜品种授粉-收获期≥0℃活动积温与籽粒含水率,分析气象因子对不同熟期油菜品种籽粒含水率的影响。结果表明:(1)4个油菜品种在授粉-收获期籽粒含水率总体呈先缓慢下降后快速下降的变化趋势,生理成熟期的平均籽粒含水率表现为中早熟品种高于中晚熟品种,收获期平均籽粒含水率随生育期的延长而减少,其中中早熟品种‘华秦油971’籽粒脱水速率最高(9.66个百分比·d^(−1)),与其他3个油菜品种差异达显著水平。(2)中早熟品种和中晚熟品种的趋势含水率拟合曲线均呈“S”型变化趋势,且中早熟品种气象含水率受气象因子的影响大,而中晚熟品种的气象含水率受气象因子影响较小。(3)试验区域内不同熟期油菜籽粒脱水主要受平均气温、最高气温、最低气温和积温等气象因子的影响,中早熟品种中平均气温(−1.125)对气象含水率表现为间接作用,最高气温(-0.347)、最低气温(−0.472)和积温(−0.936)表现为直接作用;中晚熟品种中平均气温(−0.847)为间接作用,最高气温(−0.288)、最低气温(−0.250)和积温(−0.877)为直接作用。(4)通径分析表明,各因子对气象含水率的决定因子中积温的R2贡献度最高,分别为0.8433(中早熟品种)和0.8130(中晚熟品种),说明积温对不同熟期油菜品种的气象含水率影响最大。逐步回归分析中所有方程拟合结果均达到极显著水平,说明方程可一定程度上解释气象因子对气象含水率的影响。 展开更多
关键词 油菜 熟期 籽粒脱水 气象因子
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樟子松人工成熟林凋落叶“三大素”含量特征及其影响因子研究
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作者 张野 雷泽勇 +3 位作者 赵国军 周凤艳 杨晓红 杨雨欣 《安徽农业科学》 CAS 2024年第6期105-109,共5页
揭示樟子松人工成熟林凋落叶“三大素”含量(木质素、纤维素、半纤维素)的变化机理及影响因子,为樟子松人工成熟林的经营提供科学依据。以辽宁省彰武县章古台镇成熟期樟子松人工林(林分生长阶段分别为43、49、65 a,林分密度分别为400、... 揭示樟子松人工成熟林凋落叶“三大素”含量(木质素、纤维素、半纤维素)的变化机理及影响因子,为樟子松人工成熟林的经营提供科学依据。以辽宁省彰武县章古台镇成熟期樟子松人工林(林分生长阶段分别为43、49、65 a,林分密度分别为400、625、800株/hm 2,各3次重复)为研究对象,对凋落叶“三大素”含量的动态及影响因子进行分析。凋落叶木质素、纤维素和半纤维素均在3月出现峰值,2月出现相对较低值。3—6月这3种成分的含量表现为先降低再升高再降低的趋势。在7月3种成分的含量差值最大,分别为木质素(432.44 g/kg)、纤维素(222.34 g/kg)、半纤维素(343.08 g/kg)。10—12月这3种成分的含量整体呈下降趋势。林分生长、林分密度及它们之间的交互作用对凋落叶的木质素、纤维素、半纤维素含量均无显著影响(P>0.05)。但从3种成分含量的均值来看,800株/hm 2林分密度下的木质素和半纤维素含量最高,400株/hm 2林分密度下的纤维素含量最高,且在不同林分密度和生长条件下3种成分含量变化趋势不同。月最大风速与樟子松凋落叶木质素含量之间呈显著正相关(P<0.05)。 展开更多
关键词 樟子松成熟林 凋落叶 木质素 纤维素 半纤维素 气候因子 林分密度
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投融资期限错配与企业全要素生产率:效应与机制 被引量:2
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作者 于然海 《福州大学学报(哲学社会科学版)》 2024年第1期42-57,171,共17页
金融机构信贷期限结构长期化与企业融资以短期为主,映射出当前中国经济发展面临的金融资源错配问题。企业的投融资期限错配应对行为,理论上会通过风险承担和风险规避对全要素生产率产生正反两种影响。利用2004—2019年中国A股非金融类... 金融机构信贷期限结构长期化与企业融资以短期为主,映射出当前中国经济发展面临的金融资源错配问题。企业的投融资期限错配应对行为,理论上会通过风险承担和风险规避对全要素生产率产生正反两种影响。利用2004—2019年中国A股非金融类上市公司数据研究发现:投融资期限错配会显著抑制企业全要素生产率提高。这一关系在企业规模小、资本密集程度高、信息不透明程度高、内部控制质量低的企业中更显著。投融资期限错配通过增强管理者风险规避程度(提高管理者短视主义)和降低风险承担水平(挤出创新投入)抑制全要素生产率提高。排除非线性效应和行业的年度趋势的影响,企业投融资期限错配的其他经济后果表现为对有形资产的偏向性配置。总之,应从供需两端发力,将提高金融机构中长期资金供给水平和公司现代化治理能力,作为支撑中国经济高质量发展的一项重要措施。 展开更多
关键词 信贷期限结构 投融资期限错配 管理者短视主义 企业全要素生产率
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表皮生长因子通过间隙连接蛋白调控小鼠卵母细胞成熟的研究
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作者 张桢 田霄峰 +2 位作者 陈杰 温碧超 马玉珍 《生殖医学杂志》 CAS 2024年第5期618-626,共9页
目的探讨表皮生长因子(EGF)促进卵母细胞成熟的作用机制。方法采用逆转录-聚合酶链反应(RT-PCR)技术,检测性未成熟昆明白实验小鼠未成熟卵母细胞复合体(COCs)和成熟COCs中11种间隙连接蛋白(Cx)基因的表达情况;采用细胞免疫荧光实验,确定... 目的探讨表皮生长因子(EGF)促进卵母细胞成熟的作用机制。方法采用逆转录-聚合酶链反应(RT-PCR)技术,检测性未成熟昆明白实验小鼠未成熟卵母细胞复合体(COCs)和成熟COCs中11种间隙连接蛋白(Cx)基因的表达情况;采用细胞免疫荧光实验,确定Cx43在未成熟/成熟COCs及卵母细胞中的表达部位;将未成熟COCs培养于0μg/L、1μg/L、10μg/L、50μg/L EGF培养基中观察其成熟率;将未成熟COCs培养于10μg/L EGF培养基中,观察0 h、4 h、8 h、12 h、16 h、20 h和24 h时间点的成熟率;将未成熟COCs和去颗粒细胞未成熟COCs分别培养于10μg/L EGF培养基中24 h,观察其成熟率;将未成熟COCs培养于10μg/L EGF培养基并分别加入0μg/L、0.1μg/L、1μg/L、10μg/L EGF受体(EGFR)抑制剂(AG),培养22~24 h后观察EGFR对EGF的作用;采用Western blot法检测未成熟COCs培养于10μg/L EGF培养基10 min、30 min、1 h和2 h后Cx43的磷酸化水平。结果RT-PCR结果显示,在小鼠未成熟/成熟COCs中Cx43和Cx45高表达。细胞免疫荧光实验结果显示,Cx43在未成熟COCs中表达于颗粒细胞的细胞膜上,在未成熟卵母细胞的细胞膜和透明带上也有高表达,且呈簇状分布;在成熟的COCs中Cx43在颗粒细胞膜上的表达量降低,在成熟卵母细胞中Cx43的表达量减少,且为均匀分布于细胞膜上,在透明带上不表达。培养于10μg/L EGF中的小鼠未成熟COCs的卵母细胞成熟率最高,达86.9%,显著高于其他不同浓度组(P<0.05)。在10μg/L EGF中培养24 h对小鼠未成熟COCs促进成熟的作用最显著,卵母细胞成熟率达86.2%,显著高于其他不同时长组(P<0.05)。将未成熟COCs去颗粒细胞后,培养于10μg/L EGF培养基中24 h后,未成熟COCs的卵母细胞成熟率没有显著变化(P>0.05)。EGFR特异性抑制剂AG能有效逆转EGF促进小鼠卵母细胞减数分裂恢复的作用,即抑制卵母细胞成熟,且1μg/L AG对EGF作用的逆转效果最显著(P<0.05)。Western blot结果显示,在未成熟COCs中,Cx43以非磷酸化形式为主;添加10μg/L EGF,培养10 min后,Cx43以磷酸化形式为主,持续至2 h时,Cx43又以磷酸化和非磷酸化两种形式存在。结论在小鼠未成熟COCs中,EGF可能通过与颗粒细胞上的EGFR结合,使Cx43快速磷酸化,促进卵母细胞减数分裂恢复和卵母细胞成熟。 展开更多
关键词 表皮生长因子 间隙连接蛋白 蛋白质磷酸化 卵母细胞成熟
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巨柏苗木天然更新的生境因子分析
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作者 焦婉婷 李永霞 +1 位作者 王昱熙 杨小林 《林业与环境科学》 2024年第3期80-86,共7页
为探讨巨柏Cupressus gigantea天然更新苗木生长的环境胁迫因子,以及造成巨柏天然更新困难、幼苗保存率低下的原因,研究选择朗县境内巨柏天然集中分布区3种地类的巨柏更新样地进行实地调查,采用空间代替时间的方法,统计了巨柏幼苗、幼... 为探讨巨柏Cupressus gigantea天然更新苗木生长的环境胁迫因子,以及造成巨柏天然更新困难、幼苗保存率低下的原因,研究选择朗县境内巨柏天然集中分布区3种地类的巨柏更新样地进行实地调查,采用空间代替时间的方法,统计了巨柏幼苗、幼树、成树株数等种群天然更新指标特征,选取了地类、坡向、土壤质地、土壤紧实度、土壤温度、干扰强度等19个影响更新苗木生长的生境因子进行相关性分析。研究结果表明:巨柏幼苗到成树建成的过程中保存率仅为1‰,符合数学模型:y=153.52x^(-3.528)(R^(2)=0.9661);巨柏苗木生长过程受到环境因子的强烈筛选,与水线、阴坡、树冠遮荫≥50%、枯落物、石砾、沙壤、疏松、湿润、均温、轻微放牧干扰和较强放牧干扰因子呈正相关;与坡地、阶地、阳坡、树冠遮荫<50%、砂砾、结皮、干燥、极端温度呈负相关;其中,苗木生长与阴坡和砂砾土呈显著相关,与疏松土壤呈极显著相关;越冬时生境因子温度的极端变化,是巨柏更新幼苗(1~5 a)生长过程中数量变化最剧烈的时期,15 a后苗木抗逆性明显增强,50%的幼树都可以顺利进入成树阶段。 展开更多
关键词 巨柏 幼苗 幼树 成树 生境因子
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成熟因子映射的双系统选星方法
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作者 李想 孙鼎 +2 位作者 安毅 陈勇 滕云龙 《电讯技术》 北大核心 2024年第3期402-408,共7页
传统的选星方法通常以遍历为手段,在可见星较多的情形下往往计算量很大。常规的遗传算法通常固定交叉和变异概率,产生不必要的时间消耗。针对这些问题,提出了引入成熟因子映射交叉概率和变异概率的双系统遗传选星算法,目的在于快速地找... 传统的选星方法通常以遍历为手段,在可见星较多的情形下往往计算量很大。常规的遗传算法通常固定交叉和变异概率,产生不必要的时间消耗。针对这些问题,提出了引入成熟因子映射交叉概率和变异概率的双系统遗传选星算法,目的在于快速地找到最优解或可接受的次优解。该方法以几何精度因子(Geometric Dilution of Precision,GDOP)为适应度,构造单染色体种群,定义成熟度来指导交叉变异操作,再经过每代精英保留策略和隔代种群数量控制,最终搜索得到符合门限的可接受解。实验结果表明,在进化200代的条件下,成熟因子映射遗传算法比常规遗传算法的搜索时间平均节省约24.75%,引入种群数量控制机制后搜索时间进一步节省了约55.32%。该方法可以快速获得稳定数学期望的可用选星集合。 展开更多
关键词 全球卫星导航系统(GNSS) 选星 几何精度因子(GDOP) 遗传算法 成熟因子
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班氏促卵助孕汤改善多囊卵巢综合征小鼠卵母细胞的质量
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作者 黎明星 岳晓蕾 +9 位作者 陈秀榕 李康梅 刘云佳 伍黎明 黄愉淋 吴媛媛 白琳 潘巧俐 何国珍 杨素芳 《中国组织工程研究》 CAS 北大核心 2025年第14期2958-2968,共11页
背景:班氏促卵助孕汤改善多囊卵巢综合征卵母细胞质量的分子机制亟待完善补充。目的:探讨班氏促卵助孕汤对多囊卵巢综合征小鼠卵母细胞质量的影响和分子机制。方法:21 d龄雌性昆明小鼠颈部皮下注射硫酸脱氢表雄酮构建多囊卵巢综合征模型... 背景:班氏促卵助孕汤改善多囊卵巢综合征卵母细胞质量的分子机制亟待完善补充。目的:探讨班氏促卵助孕汤对多囊卵巢综合征小鼠卵母细胞质量的影响和分子机制。方法:21 d龄雌性昆明小鼠颈部皮下注射硫酸脱氢表雄酮构建多囊卵巢综合征模型,连续给药21 d,记录动情周期及妊娠情况,ELISA检测血清性激素水平,Annexin V染色检测卵母细胞凋亡率,DCFH-DA荧光探针检测卵母细胞内活性氧水平,免疫荧光法观察卵母细胞纺锤体及染色体情况,网络药理学及分子对接验证班氏促卵助孕汤核心有效成分与卵母细胞成熟相关因子(生长分化因子9和骨形态发生蛋白15)结合活性,实时荧光定量PCR和Western blot检测卵母细胞中生长分化因子9和骨形态发生蛋白15的mRNA及蛋白表达水平。结果与结论:①班氏促卵助孕汤中的成分(槲皮素、山奈酚、β-谷甾醇)与生长分化因子9、骨形态发生蛋白15具有良好的结合活性;②班氏促卵助孕汤能恢复小鼠动情期,改善性激素紊乱和妊娠情况,降低细胞凋亡率、活性氧水平、纺锤体组装异常率、染色体丢失率(P<0.01,P<0.05),促进生长分化因子9、骨形态发生蛋白15 mRNA和蛋白表达(P<0.01,P<0.05)。结果表明,班氏促卵助孕汤可能通过调控生长分化因子9和骨形态发生蛋白15的基因表达,改善多囊卵巢综合征小鼠卵母细胞质量,提高生育力。 展开更多
关键词 班氏促卵助孕汤 多囊卵巢综合征 小鼠卵母细胞 体外成熟 生长分化因子9 骨形态发生蛋白15 妊娠 不孕
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过表达TSR2通过下调PI3K/AKT信号通路抑制胃癌细胞的增殖和侵袭
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作者 夏勇生 王炼 +3 位作者 陈孝华 张雨路 孙奥飞 陈德利 《南方医科大学学报》 CAS CSCD 北大核心 2024年第5期913-919,共7页
目的探讨TSR2核糖体成熟因子在胃癌中的表达情况及其与胃癌恶性演进的相关性,并分析其潜在的作用机制。方法纳入105例胃癌患者资料,分析TSR2在胃癌组织中表达水平及其对胃癌恶性进展、术后5年生存率的影响;GO及KEGG富集分析预测TSR2的... 目的探讨TSR2核糖体成熟因子在胃癌中的表达情况及其与胃癌恶性演进的相关性,并分析其潜在的作用机制。方法纳入105例胃癌患者资料,分析TSR2在胃癌组织中表达水平及其对胃癌恶性进展、术后5年生存率的影响;GO及KEGG富集分析预测TSR2的生物学功能及可能的作用机制;通过慢病毒转染技术上调和下调TSR2在胃癌细胞系(MGC-803)的表达水平,并采用CCK-8、Transwell评估其对MGC-803细胞增殖、侵袭及迁移的影响;Western blot检测p-PI3K、p-AKT表达。结果TSR2在胃癌组织的表达水平显著低于癌旁组织(P<0.001),且TSR2的表达水平与CEA、CA19-9、T分期及N分期相关(P<0.05)。单因素联合多因素分析显示,TSR2低表达(P=0.020)、CEA≥5μg/L(P=0.021)、CA19-9≥37 kU/L(P=0.001)、T3~T4分期(P=0.039)和N2~N3分期(P=0.027)是独立影响胃癌患者施行根治术后5年生存率的风险因子。生存分析结果显示,TSR2表达水平与胃癌患者术后5年生存率呈正相关(P<0.001)。生物信息学富集分析预测TSR2的功能可能与PI3K/AKT信号通路相关。CCK-8和Transwell实验结果显示,上调TSR2可抑制胃癌细胞的增殖、迁移和侵袭(P<0.05),下调则反之(P<0.05)。Western blot结果显示过表达TSR2可下调胃癌细胞中磷脂肌醇3激酶(PI3K)和蛋白激酶B(AKT)的磷酸化,敲低则反之(P<0.05)。结论TSR2在胃癌组织中低表达并影响患者预后,其可能与下调PI3K/AKT信号通路抑制胃癌细胞的增殖、侵袭与迁移有关。 展开更多
关键词 胃癌 TSR2核糖体成熟因子 PI3K/AKT 增殖 侵袭
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智能建造能力评估模型研究
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作者 程志军 王荣 +1 位作者 方敏进 廖智强 《建筑技术》 2024年第18期2277-2279,共3页
智能建造是信息技术与建造技术融合发展形成的新型建造方式。基于能力成熟度理论,构建了“能力要素-能力域-能力子域”架构的智能建造能力评估模型,逐项阐述了能力子域的含义及其评价要点,为编制智能建造能力评价标准建立了基础条件。
关键词 智能建造 能力要素 成熟度模型
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青少年起病的成人型糖尿病3型合并5型1例并文献复习
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作者 李丽娟 龚柳平 +3 位作者 郑爱琳 杨巧玲 蒲丹岚 张颖 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第6期848-855,共8页
报告1例青少年起病的成人型糖尿病(maturity-onset diabetes of the young,MODY)3型(MODY3)合并5型(MODY5)患者的临床特征、诊断及治疗,并复习相关文献。利用MODY(1~14型)基因外显子二代测序和Sanger测序验证MODY患者及其母亲,结合临床... 报告1例青少年起病的成人型糖尿病(maturity-onset diabetes of the young,MODY)3型(MODY3)合并5型(MODY5)患者的临床特征、诊断及治疗,并复习相关文献。利用MODY(1~14型)基因外显子二代测序和Sanger测序验证MODY患者及其母亲,结合临床表型及基因检测结果,该患者诊断为MODY3合并MODY5,给予胰岛素及利格列汀治疗,观察血糖变化。临床医师应提高对MODY临床表型的认识,对于合并先天性胰腺和肾脏发育不全、高密度脂蛋白胆固醇升高,无自发酮症、胰岛素分泌缺陷,胰岛自身抗体阴性,无明显胰岛素抵抗,非肥胖的青少年糖尿病患者应行基因检测以筛查MODY,精准诊断并予以个体化治疗将有助于血糖水平达标及改善生活质量,并指导优化生育。 展开更多
关键词 青少年起病的成人型糖尿病 肝细胞核因子1α 肝细胞核因子1β 肾囊肿 胰腺发育不全
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