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Expression patterns of OCT4, NANOG, and SOX2 in goat preimplantation embryos from in vivo and in vitro

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Journal of Integrative Agriculture 2015年第7期14卷 1398-1406页

作者： yu xiao-li ZHAO xiao-e WANG Hua-yan MA Bao-hua College of Veterinary Medicine Northwest A&F University Key Laboratory of Animal Biotechnology Ministry of Agriculture

The transcription factors, including OCT4, NANOG, and SOX2, played crucial roles in the maintenance of self-renewal and pluripotency in embryonic stem cells （ESCs）. They expressed in preimplantation mammalian development with spa- tio-temporal pattern and took part in regulation of development. However, their expression and roles in goat had not been reported. In the present study, the expression of OCT4, NANOG, and SOX2 in goat preimplantation embryos both in vivo and in vitro were detected by real-time RCR and immunofluorescence. For in vivo fertilized embryos, the transcripts of OCT4, NANOG, and SOX2 could be detected from oocytes to blastocyst stage, their expression in morula and blastocyst stages was much higher than other stage. OCT4 protein was detected from oocyte to blastocyst, but the fluorescence was more located-intensive with nuclei from 8-cell stage, its expression present in both inner cell mass （ICM） and trophoblast cells （TE） at blastocyse stage. NANOG protein was similar to OCT4, the signaling of fluorescence completely focused on cell nuclei, while the SOX2 firstly showed nuclei location in morula. Comparing to in vivo fertilized embryo, the mRNA of these three transcription factors could be detected at 8-cell stage in parthenogenetic embryos （in vitro）. Thereafter, the expressional level rose gradually along with embryo development. The locations of OCT4 and NANOG proteins were similar to in vivo fertilized embryos, and they located in cell nuclei from morula to blastocyst stage, while SOX2 protein firstly could be detected in cell nuclei at 8-cell stage. These differences suggested that OCT4, NANOG, and SOX2 played different function in regulating development of goat preimplantation embryos. These results may provide a novel insight to goat embryo development and be useful for goat ESCs isolation.

关键词： goat OCT4 NANOG SOX2 embryo expression pattern

Magnesium based degradable biomaterials： A review

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Frontiers of Materials Science 2014年第3期8卷 200-218页

作者： Xue-Nan GU Shuang-Shuang li xiao-Ming li yu-Bo FAN Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing 100191 China

Magnesium has been suggested as a revolutionary biodegradable metal for biomedical applications. The corrosion of magnesium, however, is too rapid to match the rates of tissue healing and, additionally, exhibits the localized corrosion mechanism. Thus it is necessary to control the corrosion behaviors of magnesium for their practical use. This paper comprehensively reviews the research progress on the development of representative magnesium based alloys, including Mg-Ca, Mg-Sr, Mg-Zn and Mg-REE alloy systems as well as the bulk metallic glass. The influence of alloying element on their microstructures, mechanical properties and corrosion behaviors is summarized. The mechanical and corrosion properties of wrought magnesium alloys are also discussed in comparison with those of cast alloys. Furthermore, this review also covers research carried out in the field of the degradable coatings on magnesium alloys for biomedical applications. Calcium phosphate and biodegradable polymer coatings are discussed based on different preparation techniques used. We also compare the effect of different coatings on the corrosion behaviors of magnesium alloys substrate.

关键词： magnesium alloy degradable biomaterial coating degradation corrosion

Preparation of Copolymer of Salen-crown Ether Complexes and its Catalytic Activation for Molecular Oxygen

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Chinese Chemical Letters 2006年第2期17卷 265-268页

作者： Rong Min WANG xiao Dong li yu Feng HE Gansu Key Laboratory of Polymer Materials Northwest Normal University Lanzhou 730070

A new stable salen Schiff base cobalt and crown ether sodium complex （SalCo-NaB18C6） was prepared through copolymerization. This copolymer complex was applied to catalytic oxidation of hydrocarbon compound with molecular oxygen without reductant, which was shown the higher activity and selectivity for ketone, and reused effectively.

关键词： Copolymeric complexes cyclohexene catalysis salen Schiff base crown ether.

Precise Supramolecular Polymerization of liquid Crystalline Block Copolymer Initiated by Heavy Metallic Salts

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Chinese Journal of Polymer Science 2022年第6期40卷 624-630页

作者： Yi-Qi Chen Bi-Xin Jin Qin li yun-Jun Luo Shu-Meng Chi xiao-yu li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijing100081China Experimental Center of Advanced Materials Beijing Institute of TechnologyBeijing100081China

Heavy metallic salts are capable to bind with proteins and cause detrimental fibrilization in living ***,we report a similar case of supramolecular polymerization and thus fibrilization from a liquid crystalline(LC)block copolymer(BCP)initiated by heavy metallic *** to the naturally-occurring process,LC BCP“monomers”could bind with metallic salts to form small aggregates,which functioned as seeds to trigger the subsequent supramolecular polymerization of the rest BCP monomers,to produce highly uniform supramolecular *** lengths of the resultant supramolecular polymer fibrils were linearly proportional to the ratios between the BCP and the metallic salts,and largely influenced by the choice of metallic cations,as well as the ***,this method was used to polymerize two different diblock copolymer“monomers”to produce pentablock supramolecular polymers in a one-pot manner.

关键词： liquid crystalline block copolymer Supramolecular polymerization Self assembly Controllability

CT血管造影与常规CT评估急性缺血性卒中评分的临床对比研究

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中国CT和MRI杂志 2025年第1期23卷 13-15页

作者：于晓丽刘奎杨扬孟令新青岛市第八人民医院急诊医学部山东青岛266100 日照市人民医院急诊医学部山东日照266200

目的本研究旨在比较早期CT评分(Aspects)及使用CT血管成像(CTA)原始图像与非增强CT (NCCT)在区分不同时间窗内缺血核心体积≥70mL的梗塞范围方面的表现。方法分析73例AIS-LVO患者的多模式CT表现。自动软件被用来计算方面区域。衰减变... 详细信息

目的本研究旨在比较早期CT评分(Aspects)及使用CT血管成像(CTA)原始图像与非增强CT (NCCT)在区分不同时间窗内缺血核心体积≥70mL的梗塞范围方面的表现。方法分析73例AIS-LVO患者的多模式CT表现。自动软件被用来计算方面区域。衰减变化定义为所有10个方面区域的相对Hounsfield单位(RHU)值与权重因子的乘积之和。各区域的Rh u值为缺血侧的H U值与对侧的HU值。由于Aspects模板中的每个区域在As pects系统中的权重不成比例,因此相应的权重因子是从多变量线性回归模型中得出的回归系数,该模型用于将区域RH U与缺血核心体积相关联。分别使用CTA和NCCT计算自动纵横比和衰减变化。结果在不同的时间窗内(Rho为0.439~0.637),衰减变化与缺血核心体积相关。以缺血核心≥为70mL,其衰减变化表现与Aspects(曲线下面积0.799~0.891)相近,与DeLong's检验(P=0.079,P=0.373)相近,CTA(AU C=0.842)与NCCT(AUC=0.838)无差异。结论Aspects区域的衰减变化与缺血核心体积相关。在脑梗塞体积的分类中,衰减变化具有与自动化方面相当的高诊断能力。复杂的评分算法不涉及衰减变化的测量。这种测量方法可以作为一种有效、快速、可靠、准确的手段来评估不同时间窗内的脑梗塞范围。通过衰减变化测量梗死体积以确定更适合再灌注治疗的患者的有用性可以在未来的临床试验中得到验证。

关键词： CT血管造影非对比CT 急性缺血性卒中 CT评分算法

A preliminary study on the teratogenesis of dexamethasone and the preventive effect of vitamin B_(12 )on murine embryonic palatal shelf fusion in vitro

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 306-312页

作者： Sheng-jun LU Wei HE Bing SHI Tian MENG xiao-yu li yu-rong liU State Key Laboratory of Oral Disease West China College of Stomatology Sichuan University Chengdu 610041 China Department of Cleft lip and Palate Surgery West China Stomatological Hospital Sichuan University Chengdu 610041 China

Excessive dexamethasone (Dex) administrated into pregnant mice during critical periods of palatal development can produce a high incidence of cleft palate. Its mechanisms remain unknown. Vitamin B12 has been shown to antagonize the tera- togenic effects of Dex, which, however, remains controversial. In this study, we investigated the effects of Dex and vitamin B12 on murine embryonic palatal shelf fusion using organ culture of murine embryonic shelves. The explanted palatal shelves on em- bryonic day 14 (E14) were cultured for 24, 48, 72 or 96 h in different concentrations of Dex and/or vitamin B12. The palatal shelves were examined histologically for the morphological alterations on the medial edge epithelium (MEE) and fusion rates among different groups. It was found that the palatal shelves were not fused at 72 h or less of culture in Dex group, while they were completely fused in the control and vitamin B12-treated groups at 72 and 96 h, respectively. The MEE still existed and proliferated. In Dex+vitamin B12 group the palatal shelves were fused at each time point in a similar rate to controls. These results may suggest that Dex causes teratogenesis of murine embryonic palatal shelves and vitamin B12 prevents the teratogenic effect of Dex on palatogenesis on murine embryos in vitro.

关键词： Dexamethasone Vitamin B12 Organ culture Cleft oalate Medial edge epithelial cells

Origin of Modulus Improvement for Epoxide-terminated Hyperbranched Poly(ether sulphone)/DGEBA/TETA Systems

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Chinese Journal of Polymer Science 2018年第8期36卷 991-998页

作者： Xue-Pei Miao Dao-Jian Cheng Ya-Dong Dai Yan Meng xiao-yu li Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China Neo Trident Technology Ltd (Beijing) Beijing 100190 China

It has been experimentally shown that epoxide-terminated hyperbranched polyether sulphone （EHBPES） can significantly improve the mechanical properties of traditional diglycidyl ether of bisphenol A/triethylenetetramine （DGEBA/TETA） systems, but the origin of the improvement is still unclear. In this work, we used molecular dynamics （MD） simulations to gain a thorough understanding of the origin of modulus improvement for EHBPES/DGEBA/TETA systems. It is found that the modulus of EHBPES/DGEBA/TETA systems increases with the increase of EHBPES loading. In addition, the crosslinking density, cohesive energy density （CED）, and free volume can be used to understand the modulus for EHBPES/DGEBA/TETA systems. It is shown that the highest modulus is achieved at 7 wt% EHBPES loading due to the highest crosslinking density and CED. When EHBPES loading is below 7 wt%, the higher CED and crosslinking density are responsible for the higher modulus. At higher loadings （〉 7 wt%）, the decreased modulus is closely related to the decreased crosslinking density and increased fractional free volume. It is expected that our results could be of great implications for designing high-performance epoxy materials.

关键词： Modulus Molecular simulation Epoxy resin

Serum calcium,albumin,globulin and matrix metalloproteinase-9 levels in acute cerebral infarction patients

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World Journal of Clinical Cases 2021年第30期9卷 9070-9076页

作者： Ting-Ting Zhong Gang Wang xiao-Qin Wang Wei-Dan Kong xiao-yu li Qian Xue yu-An Zou Department of Neurology The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Hemorrhagic transformation(HT)is a common complication in patients with cerebral ***,its pathogenesis is poorly *** knowledge of factors that may increase risk for HT may help in improving the safety of thrombolytic *** To investigate the predictive value of serum calcium,albumin,globulin and matrix metalloproteinase-9(MMP-9)levels for HT after intravenous thrombolysis(IVT)in patients with acute cerebral *** Five hundred patients with acute cerebral infarction who received IVT with alteplase within 4.5 h after the onset of disease between January 2018 and January 2021 at our hospital were selected as the study *** were divided into groups based on computed tomography scan results of the brain made within 36 h after *** patients with HT were enrolled in an observation group and 460 patients without HT were enrolled in a control *** calcium,albumin,globulin and MMP-9 levels were compared between the two *** analysis was used to discuss the relationship between these indices and *** The previous history of hypertension,diabetes,atrial fibrillation,cerebrovascular diseases,smoking and alcohol intake were not associated with HT after IVT in patients with acute cerebral infarction(all P>0.05).The National Institutes of Health stroke scale(NHISS)score was associated with HT after IVT in patients with acute cerebral infarction(Plin and MMP-9 were significantly higher in the observation group than in the control group(all Plins and MMP-9 were independent factors influencing the occurrence of HT following IVT in patients with cerebral infarction(Plin and MMP-9 levels are risk factors for HT after IVT

关键词： Stroke Intravenous thrombolytic therapy Intracranial hemorrhage Blood calcium Albumin Globulin

Genetic, environmental and other risk factors for progression of retinitis pigmentosa

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International Journal of Ophthalmology(English edition) 2022年第5期15卷 828-837页

作者： Zi-Yang Huang li-Na liang Ya-Min li Kai Xu xiao-yu li Eye Hospital China Academy of Chinese Medical SciencesBeijingChina

Retinitis pigmentosa(RP) is a commonly inherited disease of the retina, which is characterized by progressive loss of visual function due to specific genetic mutations. There are many risk factors that may have effect on the progression of RP, such as inheritance patterns, genotype, gender, age, smoking, physical activity, and other demographic and environmental factors. Baseline visual field conditions, changes of ellipsoid zone, photoreceptor layer thickness, and choroidal structure are reported to be the phenotype risk factors for RP progression. Moreover, aqueous flare and high-sensitivity C-reactive protein are probable inflammation biomarkers for assessing the progression of RP. Increased oxidative stress is considered to be one of the potential factors for the existence of RP. The risk factors can be combined to form a corresponding prediction model to predict disease progression. This review is to summarize the current literature that studies the genetic, environmental, phenotypic, demographic, inflammatory and other risk factors of RP progression and discuss the most reliable risk factors that could provide predictive models.

关键词： retinitis pigmentosa risk factor progression genetics phenotype inflammation prediction