Brain-derived neurotrophic factor expression in dorsal root ganglion neurons in response to reanastomosis of the distal stoma after nerve grafting

Studies have shown that retreatment of the distal stoma after nerve grafting can stimulate nerve regeneration. The present study attempted to verify the effects of reanastomosis of the distal stoma, after nerve grafting, on nerve regeneration by assessing brain-derived neurotrophic factor expression in 2-month-old rats. Results showed that brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after autologous nerve grafting post sciatic nerve injury, peaked at 14 days, decreased at 28 days, and reached similar levels to the sham-surgery group at 56 days. Brain-derived neurotrophic factor expression in L2-4 dorsal root ganglia began to increase 3 days after reanastomosis of the distal stoma, 59 days after autologous nerve grafting post sciatic nerve injury, significantly increased at 63 days, peaked at 70 days, and gradually decreased thereafter, but remained higher compared with the sham-surgery group up to 112 days. The results of this study indicate that reanastomosis of the distal stoma after orthotopic nerve grafting stimulated brain-derived neurotrophic factor expression in L2.4 dorsal root ganglia.

SINAPYL ALCOHOL DERIVATIVES AND OTHER CONSTITUENTS FROM THE ROOTS OF LIGULARIA NELUMBIFOLIA

Phytochemical investigation of the roots of Ligularia nelumbifolia afforded three new sinapyl alcohol derivatives together with two other novel constituents.Their structures were elucidated by high field 1D and 2D NMR techniques and chemical transformations.

Changes in compressed neurons from dogs with acute and severe cauda equina constrictions following intrathecal injection of brain-derived neurotrophic factor-conjugated polymer nanoparticles

This study established a dog model of acute multiple cauda equina constriction by experimental constriction injury （48 hours） of the lumbosacral central processes in dorsal root ganglia neurons. The repair effect of intrathecal injection of brain-derived neurotrophic factor with 15 mg encapsulated biodegradable poly（lactide-co-glycolide） nanoparticles on this injury was then analyzed. Dorsal root ganglion cells （LT） of all experimental dogs were analyzed using hematoxylin-eosin staining and immunohistochemistry at 1,2 and 4 weeks following model induction. Intrathecal injection of brain-derived neurotrophic factor can relieve degeneration and inflammation, and elevate the expression of brain-derived neurotrophic factor in sensory neurons of compressed dorsal root ganglion Simultaneously, intrathecal injection of brain-derived neurotrophic factor obviously improved neurological function in the dog model of acute multiple cauda equina constriction. Results verified that sustained intraspinal delivery of brain-derived neurotrophic factor encapsulated in biodegradable nanoparticles promoted the repair of histomorphology and function of neurons within the dorsal root ganglia in dogs with acute and severe cauda equina syndrome.

Low-frequency electrical stimulation improves neurite outgrowth of dorsal root ganglion neurons in vitro via upregulating Ca^(2+)-mediated brain-derived neurotrophic factor expression

Short-term, low-frequency electrical stimulation of neural tissues significantly enhances axonal regeneration of peripheral nerves following injury. However, little is known about the mechanisms of electrical stimulation to induce neurite outgrowth. In the present study, short-term, low-frequency electrical stimulation, using identical stimulation parameters of in vivo experiments, was administered to in vitro dorsal root ganglion （DRG） neurons. Enhanced neurite outgrowth, as well as synthesis and release of brain-derived neurotrophic factor （BDNF）, were examined in electrical stimulation-treated DRG neuronal cultures. Because the effects of electrical stimulation on neuronal intracellular signaling molecules are less reported, classic calcium intracellular signals are directly or indirectly involved in electrical stimulation effects on neurons. Cultured DRG neurons were pretreated with the calcium channel blocker nifedipine, followed by electrical stimulation. Results suggested that electrical stimulation not only promoted in vitro neurite outgrowth, but also enhanced BDNF expression. However, nifedipine reduced electrical stimulation-enhanced neurite outgrowth and BDNF biosynthesis. These results suggest that the promoting effects of electrical stimulation on DRG neurite outgrowth could be associated with altered calcium influx, which is involved induction of neuronal BDNF expression and secretion.

DERIVED SEQUENCES AND THE FACTOR SPECTRUM OF THE PERIOD-DOUBLING SEQUENCE

Factor properties and their structures are important themes in combinatorics on words.Let D be the infinite one-sided sequence over the alphabet{a,b}generated by the period-doubling substitutionσ(a)=ab andσ(b)=aa.In this paper,we determine the derived sequence D_(ω)(D)for any factorω■D,and study some factor spectra using the structures of derived sequences.We also prove the reflexivity property of derived sequences.

Electroacupuncture upregulated platelet derived growth factor expression in spared dorsal root ganglion of cats

A bilateral spared dorsal root ganglion model was established in healthy adult cats by bilateral resection of L1-5 and L7-S2 dorsal root ganglia. L6 dorsal root ganglia were spared. Zusanfi （ST36） and Xuanzhong （BL39） or Futu （ST32） and Sanyinjiao （SP6） were alternatively electro-stimulated on the right leg. Immunohistochemical staining of anti-serum platelet-derived growth factor demonstrated that the number of total neurons and medium-small sized platelet-derived growth factor positive neurons was significantly decreased on the 7~ day following injury. After 7 days of acupuncture, the total number of positive and large neurons staining for platelet-derived growth factor on the acupuncture side significantly increased compared to the non-acupuncture side. After acupuncture for 14 days, the total positive and medium-small sized neurons significantly increased compared with the non-acupuncture side. Results indicate that acupuncture promoted the synthesis of platelet-dedved growth factor in spared dorsal root ganglia.

Pain-related mediators underlie incision-induced mechanical nociception in the dorsal root ganglia

Approximately 50-70% of patients experience incision-induced mechanical nociception after sur- gery. However, the mechanism underlying incision-induced mechanical nociception is still unclear. Interleukin-10 and brain-derived neurotrophic factor are important pain mediators, but whether in- terleukin-10 and brain-derived neurotrophic factor are involved in incision-induced mechanical no- ciception remains uncertain. In this study, forty rats were divided randomly into the incision surgery （n = 32） and sham surgery （n = 8） groups. Plantar incision on the central part of left hind paw was performed under anesthesia in rats from the surgery group. Rats in the sham surgery group re- ceived anesthesia, but not an incision. Yon Frey test results showed that, compared with the sham surgery group, incision surgery decreased the withdrawal threshold of rats at 0.5, 3, 6 and 24 hours after incision. Immunofluorescence staining in the dorsal root ganglia of the spinal cord （L3-5） showed that interleukin-10 and brain-derived neurotrophic factor were expressed mainly on small- and medium-sized neurons （diameter 〈 20 pm and 20-40 pm） and satellite cells in the dorsal root ganglia of the spinal cord （L3-5） in the sham surgery group. By contrast, in the surgery group, high expression of interleukin-10 and brain-derived neurotrophic factor appeared in large-sized neurons （diameter 〉 40 pm） at 6 and 24 hours after incision surgery, which corresponded to the decreased mechanical withdrawal threshold of rats in the surgery group. These experimental findings suggest that expression pattern shift of interleukin-10 and brain-derived neurotrophic factor induced by inci- sion surgery in dorsal root ganglia of rats was closely involved in lowering the threshold to me- chanical stimulus in the hind paw following incision surgery. Pain-related mediators induced by in- cision surgery in dorsal root ganglia of rats possibly underlie mechanical nociception in ipsilateral hind paws.

词根频率和语义透明度对英语二语后缀派生词加工模型影响的实证研究

本研究采用词汇判断任务,探究词根频率、语义透明度及其交互效应对英语二语后缀派生词加工模型的影响。实验发现:(1)在反应时上词根频率主效应显著,高频词根派生词的平均反应时低于低频词根派生词;(2)在反应时上语义透明度主效应显著,语义透明派生词的平均反应时低于语义晦涩派生词;(3)在正确率上二者交互效应显著,语义透明度对低频词根派生词正确率的影响更大,词根频率对语义晦涩派生词正确率的影响更大。据此,我们构建中国学习者英语二语后缀派生词分解加工模型:分为词素分解和词素整合两个阶段,词根频率和语义透明度均影响派生词加工的时间进程,二者交互影响派生词的加工质量。

大黄防治疫病的理论及应用探微

大黄是常用的攻下驱邪药,驱逐停滞,效用以除血之滞、饮之积和食之积为主。疫病里热积滞用大黄通食滞,常见大黄类方有表里双解的宣白承气汤和防风通圣散;调畅气机的治疫大黄类方有升降散和大柴胡汤等。疫病血瘀证用大黄导血滞如桃核承气汤,疫病津液代谢障碍用大黄除水滞如茵陈蒿汤等。

基于学术发展逻辑的研究生学术英语教学

语言层面的学术发展逻辑为“阅读文献与挖掘研究问题”“撰写文章摘要”“参会寻求同行反馈”“投稿发表”。本文以该学术发展逻辑为基础,增补“夯实英语基础”环节,考察硕博研究生学术英语课程中的教学点和科研点。“打基础”环节探讨词根和派生词之间具体/微观/常见和抽象/宏观/罕见的关系,并以人类认知过程中的赋名顺序予以解释。“文献与问题”环节要求学生自主阅读相关文献,提出研究问题并集体讨论。“文章摘要撰写”环节分析语言学国际顶刊摘要IMRD四语步,发现英语时态多用现在时,语态多为主动,人称以第一人称(多见于MR语步)和第三人称(多见于ID语步)混用为主,且独作文章多使用第一人称单数:要求学生据此自主调查所在学科英语摘要的语篇特征。“参会研讨”环节举办模拟国际学术会议,锻炼学生的办会、参会和同行评议能力。“投稿”环节从cover letter出发,讨论文章投稿中的关键点。本文所述研究生学术英语教学符合学术发展逻辑,可切实提高硕博研究生的学术水平,具备推广价值。

现代汉语贬抑性评价构式“破NP”研究

现代汉语中的“破NP”构式是主观性强的贬抑性评价构式,其构式义丰富,可分为直接贬抑、间接贬抑、假性贬抑、自我贬抑、反预期贬抑五种不同情况,这五种构式义与构素“NP”之间是互相选择的关系,从历时角度来看,“破NP”经过重新分析从动宾结构演变为定中结构,引发了“破”从动词到形容词的词性演变过程,最终“破”虚化为泛义形容词,“破NP”构式由此产生。在东北官话中,“破NP”构式常与方言特征鲜明的程度副词“老”结合成强贬抑性评价构式“老破NP”,“老破NP”构式又派生出“老NP”构式,属于纯粹的强贬抑性评价构式。“破NP”作为现代汉语中最常用的强贬抑性构式之一,其深层的构式义、词义演变过程及其在方言中的派生形式对于接受国际中文教育的留学生来说是很难理解的,因此我们希望通过对以上三个方面的探究修正留学生对“破NP”构式理解上的偏误,并激发留学生对中文当中其他语言现象含义及其演变过程的主动理解和探索。

汉俄语言接触中俄语对汉语语义系统的影响新探

从十月革命胜利至新中国成立初期,汉俄语言之间发生了史无前例的大规模密切接触。汉俄语言接触研究对于丰富中国社会语言学语言接触理论,认识当代汉语的形成和发展具有重要意义。本文以社会语言学语言接触理论为视角,综合运用共时研究法、历时研究法和汉俄对比法,依托汉俄构词学、词汇学和语义学理论知识,从显性影响、隐性影响、组合关系影响和聚合关系影响四个方面出发,深入探讨汉俄语言接触中俄语对汉语语义系统的影响。

论龙部字考证与龙文化再阐释

龙属炎黄子孙普遍认可的文化符号、集体记忆、共同图腾,并以文字代码的形式层累凝练为中华民族共同体的文明根脉、意识底座。考诸《汉语大字典》龙部字词,探悉古人以龙为核心构建一语义鲜明、错落有致的龙族认知范畴,有力证实了龙文化起源于中国本土。有别于西方的“dragon”,龙在中华民俗信仰中以雨神、水神的灵异身份频繁出现,是东亚农耕文明发达的忠实见证。更为重要的是,褒龙爱龙之共同情感始终贯穿于中华民族的历史长河,最终演绎成一种极为稳定的“大一统”叙事结构、民族共识。要之,龙堪称铸牢中华民族共同体意识不可或缺的文化资源、精神标识,弥漫着无穷的生命活力、浩然正气。

牙釉基质衍生物促进人工根面牙本质龋的再矿化

目的探讨牙釉基质衍生物(enamel matrix derivative,EMD)对人工根面牙本质龋再矿化作用的影响。方法将牛牙根面牙本质样本放置在脱矿溶液中,形成人工龋损样本,采用简单随机抽样法分为EMD组(30 g/L EMD,实验组)、氟化钠(sodium fluoride,NaF)组(1 g/L NaF,阳性对照组)和去离子水(distilled and deionised water,DDW)组(阴性对照组),进行pH循环处理8 d,每天6次。使用扫描电子显微镜(scanning electron microscope,SEM)及偏振光显微镜(polarized light microscopy,PLM)观察各组处理前后龋损形态学的变化情况,并使用横断显微照相技术(transverse microradiography,TMR)检测处理前后矿物质丢失量、龋损深度和矿物含量的变化情况。结果pH循环处理后,SEM的表面形态学图像和PLM的垂直形态学图像均显示,EMD组和NaF组人工根面牙本质龋的矿物质沉积增加,而DDW组无矿物质沉积。同时,TMR结果显示,与DDW组相比,EMD组矿物丢失较低,龋损深度较浅,矿物含量较高(P<0.05)。结论釉基质衍生物能促进根面牙本质龋的再矿化,具有成为一种有效的根面无创防龋制剂的潜力。

网络热词“X精”的来源、语义及其派生规律

近些年来,接连上榜年度“十大流行语”的“戏精”“杠精”“柠檬精”,都属于“X精”族群成员,它们均由负载与事者某类特征信息的“X”和表某一类人(具有某一特征)的“精”加合构成。流行于网络平台的“X精”并不是近年才新造的,它是通过继承既有词语的结构特点,再通过复制与类推派生而来的。由于“X精”中的“精”之语义偏离与泛化,使得能够进入“X”的内容逐渐扩展,随机、偶发的临时性造词不断涌现。在语法方面,“X精”也拓展出一些谓词性的用法。这些新造词和零星的新现象能否被大众广泛接受,成为“沉淀”的语言,仍有待于实践与时间的双重检验。

汉语哈萨克语派生词构成方式对比探析

随着事物的发展、科技的进步及时代的变迁,词汇作为语言中对环境改变反映最敏锐的成员也在随之发生变化,关于词汇的分析研究始终是一个热点问题。派生词又称附加词,属于合成词的一种,在词汇中占有一定比例,也是人们日常交流生活中常用的一类词。该文采用对比语言学理论方法,对汉语派生词的构成方式和哈萨克语派生词的构成方式进行对比,综合目前学界较为认可的构词方式,将派生词的构成方式分为前加式和后加式来分析两种语言中派生词的构成特点,总结两种语言中派生词的相同点和不同点,希望能为哈萨克语学习者提供帮助。

社会新闻标题中网络词语使用研究--以“特种兵式旅游”为例

网络词语是网络媒体语言的重要组成部分,如今各个门户网站更新社会新闻时都不吝啬且热衷于使用网络词语来报道。这种新型的社会新闻收集方式已渗透到广大居民的生活中,使得网络词语的关注度不断攀升,成为无数网民了解社会、传播话题的重要表达方式。比如“村BA”、爱达未来、“特种兵式旅游”等,人人在说,人人在用。有媒体称此类逐渐庞大的网络词语,逐渐使当今社会呈现出一种渐渐明显的“词媒体”时代,它们被广泛应用到社会新闻报道的标题中,用作传递信息的载体,最大限度地加快传播和记忆速度。该文以“特种兵式旅游”网络词语在社会新闻标题中的应用为依托,来分析该网络词语的产生、句法结构、语义特征及其在新闻标题中的语用价值,并着重探讨“特种兵式×”的衍生机制。

A FAMILY OF MODAL METHODS FOR COMPUTING EIGENVECTOR DERIVATIVES WITH REPEATED ROOTS

A family of modal methods for computing eigenvector derivatives with repeated roots are directly derived from the constraint generalized inverse technique which is originally formulated by Wang and Hu. Extensions are made to Akgun's method to allow treatment of eigensensitivity with repeated roots for general nondefective systems, and Bernard and Bronowicki's modal expansion approach is expanded to a family of modal methods.

Microwave digestion polarography for determining seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection simultaneously

The sensitive second derivative waves of Cu(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Fe(Ⅱ)and Mn(Ⅱ),forming in the substrate solution(pH=9.26)consisting of ammonia,ammonium chlorid,gelatin and ascorbic acid were researched.The peak potentials of the polarographic waves of the seven ions are at about 0.48,0.63,0.79,1.04,1.28,1.44 and 1.60 V respectively.Combining with microwave technique,a new method for the simultaneous determination of the seven trace elements in Chinese traditional medicine was developed.The method is easy to operate,rapid,simple and convenient.When the signal-to-noise rate equals 3,the detection limits of Cu,Pb,Cd,Ni,Zn,Fe and Mn are 4.2×10 3,5.3×10 3,2.1×10 3,5.8×10 4,3.0×10 3,7.7×10 4 and 1.1×10 3 μg/mL respectively.Well linear relationships exist between the concentrations and the peak currents when Cu,Pb,Cd,Ni,Zn,Fe and Mn concentrations are within 8.5×10 3 10,9.7×10 3 10,4.5×10 3 10,1.2×10 3 10,6.4×10 3 10,1.5×10 3 10 and 2.8×10 3 10 μg/mL,respectively.The method has been used to the simultaneous determination of the seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection,the relative standard deviations(RSDs)of the Cu,Pb,Cd,Ni,Zn,Fe and Mn in the two medicines are 3.9% and 5.8%,4.0% and 4.1%,4.3% and 5.7%,4.9% and 5.3%,4.4% and 4.7%,3.5% and 4.0%,0.51% and 2.8%,respectively;the comparisons of the determination results with the values obtained by the standard method indicate that the presented method has very well veracity.

Correlation between the Standard Formation Enth alpy and the Path Index of Pyridine Derivatives

A formulated as △fH m ? (PPDs,g)=a+ΣbiPi + cifi is put forward for estimating standard formation enthalpies of pyridine-derivatives (PDDs), in which,P i is path index andc i f i is an amended term of interaction between substituent and N atom on pyridine ring. The Calculations based on the model were carried out for some pyridine-derivatives. The values of standard formation enthalpy calculated are consistent with those in literature.