不同张力对家兔正中神经形态的影响

采用弦式加载，造成对家兔正中神经的单纯性牵拉，并对神经在单纯性牵张力作用下的形态变化和导致神经急性牵拉伤的临界张力值进行了研究。结果表明：当施加到非游离正中神经上的总应力为２３ｇ·（ｍｍ＾２）＾－１时，内部神经纤维的延长达到生理极限；当总应力升至６１ｇ·（ｍｍ＾２）＾－１时，内部神经纤维的延长达到生理极限；当应力升至２３ｇ·（ｍｍ＾２）＾－１时，神经纤维出现损伤；应力升至１８２ｇ·（ｍｍ＾２）＾－     

血管、神经和肌肉的扩张研究

对扩张的隐血管（动脉和静脉）、隐神经和缝匠肌的几何尺寸、肌节数量、应力－应变关系和应力松弛进行了研究。采用了１６只狗作为实验对象，因为狗软组织生物力学特性和人体生物力学特性非常相似。本实验动物模型采用间断注水低压（＜５．３３ｋＰａ）扩张方式对血管、周围神经及骨骼肌的扩张是安全而有效的。本研究为临床上替代血管、神经和肌肉瓣的游离移植提出了一种可选择的新技术。     

猪眼角膜的本构方程和应力松弛

通过猪眼角膜单向拉伸系统试验来确定其显著的非线性应力应变关系。若合适地考虑到试件的松弛应变，就可发现测出的应力－应变数据非常适合于用来描述典型胶原组织的害虫指数函数。在不同伸长比下测出了应力松弛程度。进而确定连续松弛谱中的三个参数。     

人脊柱T_(6、7)段椎骨应力松弛蠕变实验研究

报道了用实验的方法对脊柱骨进行单向常应力－蠕变实验和单向常应变－应力松弛实验。得出应力、应变和时间相关的不同效应。     

模拟腰椎前路、后路间盘摘除术T12-L5腰段脊柱应力松弛蠕变实验研究

研究了18例新鲜尸体T12－L5腰段脊柱应力松弛，蠕变特性。测定了完整脊柱（正常组）及模拟前路（对照1组），后路手术（对照2组）腰段脊柱的应力松弛和蠕变效应，得出了在恒应变，应力条件下应力－时间曲线及数据，用回归分析的方法处理实验数据，得出了归一化应务松弛，蠕变函数及曲线，对前路间盘摘除术与后路间盘摘除术对脊柱粘弹性的影响进行分析讨论。     

胎儿臂丛神经上干粘弹性实验研究

研究了 30具新鲜胎儿尸体臂丛神经上干的拉伸力学性质和粘弹性力学性质 ,对臂丛神经上干进行单向拉伸实验 ,得出了破坏载荷、强度极限、最大应变。对臂丛神经上干进行应力松弛、蠕变实验 ,得出了应力松弛、蠕变实验数据和曲线。对实验数据进行归一化处理 ,得出了归一化应力松弛函数、蠕变函数。以回归分析的方法处理实验数据 ,得出回归系数 ,很好地拟合了实验曲线。实验结果表明 6～ 7月龄胎儿臂丛神经上干的破坏载荷、强度极限、最大应变小于 8月龄以上的胎儿。男女胎儿臂丛神经之间拉伸力学性质差异不显著 ,低月龄胎儿臂丛神经 72 0 0S应力松弛量大于高月龄组 ,蠕变量差异不显著     

视神经归一化应力松弛函数

目的通过对视神经应力松弛实验研究,摘清其松弛特性,为研究现神经的损伤村u绝提供粘弹性力学参数。方法取2125岁正常国人急性gffe致死的新鲜男性尸体视神经8个标本。以读数显微镜测量试样原始尺寸,试样长为15－ZOmm。直径3．45－3．65mm。试验装置为日本岛津AG－IOTA自动控制电子万能达滑封叽。将经过预调处理的试样装夹到夹具L,夹具与有机玻璃缺连接,玻璃缸内装有PH值为7．4的生理盐水,试样置于生理盐水中,装有试样的夹具与有机玻璃缺连接,本实验在365tol℃的温度场下进行。以SO％／min的应变增加速度对试样施加常应变,当应…     

人脊柱棘间韧带与黄韧带应力松弛实验的研究

从应力松弛力学特性角度对棘间韧带和黄韧带进行定量分析,为人工韧带材料研究和韧带损伤吻合手术提供应力松弛力学参数。将标本装夹于软组织夹具中,之后装夹于电子万能试验机夹头内,驱动机器以1%/s的应变增加速度对标本施加拉应变,在36.5℃温度场下进行实验,采集90个数据,实验结束后计算机自动输出7 200 s之间应力松弛数据和曲线。棘间韧带组7 200 s应力松弛量为1.06 MPa,黄韧带组7 200s应力松弛量为1.62 MPa。棘间韧带和黄韧带具有不同的应力松弛力学特性。     

人肺组织的力学特性

在双向拉伸状态下，测量了人肺的应力——应交关系。为消除边界影响，用电视尺寸分析仪仅对试件中央部分（称靶标）进行测量。借PDP－11计算机对数据采样和贮藏。用传感器测定侧向力。试验在pH6.3～7.4和37℃条件下进行。在不同pH值时，试验结果无明显差异。结果表明：肺组织具有很高的非线性应力——应变关系，滞后现象显著。在应变率改变20倍时，应力——应变关系未受影响。试验同时测得蠕变和应力松弛特征关系。     

非线性模型在椎间盘黏弹性特性分析中的应用

目的 构建变参数非线性模型,研究人体椎间盘在循环应变状态下的应力松弛特性。方法 采用变参数非线性模型结合椎间盘应力松弛和蠕变反应的实验数据,研究循环应变状态下椎间盘的应力松弛特性,比较线性与非线性模型在循环状态下椎间盘黏弹性特性的差异。结果 采用变参数非线性模型得出的循环模量和松弛系数在0.01Hz循环状态下与实验模型非常接近,得出的循环模量在0.1和1 Hz下也与实验值相近,但是得出的松弛系数在0.1和1 Hz下失真严重。结论 在压缩应变作用下椎间盘经历的是一个非线性的应力行为,非线性变参数模型更符合研究在循环应变下椎间盘应力松弛反应的需要。     

免费师范生学习动机强度及其影响因素研究

目的对免费师范生和非免费师范生的学习动机强度及其影响因素的差异性进行调查分析。方法以陕西师范大学、南京师范大学、河北师范大学的师范生为被试,采用问卷调查和结构访谈相结合的方法。结果①免费师范生和非免费师范生在内生动机和动机总强度上不存在显著差异(F=1.788,-0.462,P>0.05),在外生动机强度上非免费师范生显著高于免费师范生(F=-2.536,P<0.05);②免费师范生和非免费师范生学习动机的年级、专业和性别主效应显著(F=9.611,P<0.001;F=6.084,P<0.05;F=9.199,P<0.01),师范生类别和年级的交互作用达到显著水平(F=4.589,P<0.01);③师范生的学习动机与时间管理、自我效能感、认知需求显著相关,时间价值感、认知需求、自我效能感对师范生学习动机具有预测作用(R2=0.314,P<0.001)。结论免费师范生和非免费师范生的学习动机水平相同。     

失面神经支配后豚鼠口轮匝肌线粒体和琥珀酸脱氢酶活性变化

目的探讨不同程度面神经失神经支配对口轮匝肌及线粒体琥珀酸脱氢酶(SDH)活性的影响。方法制造颞骨外面神经麻痹豚鼠模型,在压榨程度相同条件下分为面神经压榨15S组、30S组,再分为观察7d组、30d组。SDH染色后,应用计算机图像分析系统进行各组纤维SDH酶含量测定,并观察线粒体结构和SDH酶阳性反应产物的变化。并应用瞬目反射方法测试15S组、30S组瞬目反射恢复时间。结果15S7d组I型和Ⅱ型SDH酶呈色反应较正常组明显减弱(P0.01),30S7d组比15S7d组SDH酶活性显着性减弱(P0.01)。15S7d组线粒体嵴少量断裂,SDH酶阳性反应颗粒轻度减少;15S30d组基本恢复正常。30S7d组线粒体嵴多量嵴断裂,SDH酶阳性反应颗粒重度减少;30d组线粒体结构和SDH酶反应颗粒轻度恢复。瞬目反射15S组恢复正常需要(36±12)d;30S组半年内未见恢复到正常。结论面神经受损伤持续时间越长,失神经支配程度越重,肌纤维及线粒体病变越重,肌功能恢复越慢,建议应早期行面神经减压术。     

Electrical field stimulation of rat mesenteric small arteries: force and free cytosolic calcium during neurogenic contractions and mechanisms of non-neurogenic relaxations

The effect of transmural electrical field stimulation (TEFS) of rat mesenteric small arteries was studied. Stimulation parameters were selected to cause tetrodotoxin (TTX) sensitive contractions. In arteries precontracted with PGF_2α in the presence of phentolamine, TTX insensitive relaxation could be induced by TEFS. The relaxing effect of TEFS required higher stimulation amplitude and duration than the contractions. Thus, by appropriately choosing stimulation parameters, contractile responses could be elicited which were little affected by any relaxing effect, while contractions were abolished by TTX at any stimulation conditions in the present study. The contractions were abolished by cold storage and almost completely inhibited by phentolamine. Thus, contractions were neurogenic and primarily caused by noradrenaline. At low frequencies, TEFS caused phentolamine sensitive increases in free cytosolic calcium with no contractions. At higher frequencies, there was a further increase in free cytosolic calcium, associated with contraction. Only at high frequencies, noradrenaline from nerves caused sensitization of the contractile filaments to free cytosolic calcium as during stimulation with exogenous noradrenaline. The relaxations were associated with decreases in free cytosolic calcium and were probably non-neurogenic since they were resistant to TTX, cold storage, capsaicin, and repeated stimulation. Furthermore, relaxations were almost completely abolished by increasing extracellular potassium to 40 mM or by adding tetraethylammonium chloride or 4-aminopyridine. Relaxations were also reduced by ouabain and potassium free conditions.     

Presynaptic effects of 4-aminopyridine and changes following a single giant impulse at the Torpedo nerve-electroplaque junction

The presynaptic changes caused by 4-aminopyridine were studied in the electric organ of Torpedo marmorata, in the resting state and during the period following transmission of a single giant discharge. Incubation with 4-aminopyridine provoked a 30-40% decrease in the density of synaptic vesicles in nerve terminals, and a similar decrease in the content of vesicular and free acetylcholine. These changes were not observed when 4-aminopyridine was applied in a low-calcium, high-magnesium solution. In the standard medium, 4-aminopyridine treated junctions were able to generate a giant electrical discharge of long duration in response to a single stimulus. During the seconds and minutes following the giant discharge, the number of synaptic vesicles was not found to be significantly altered in the whole population of nerve terminals. However, new membranous structures--looking like sacs with double membranes encircling a part of cytoplasm--were seen in approximately 25% of nerve endings; in those terminals, the number of synaptic vesicles was significantly decreased. At this stage, the junctions had not recovered their capability to generate a second giant discharge of full size and the yield of acetylcholine, adenosine 5'-triphosphate (ATP) and creatine phosphate was diminished. Thirty minutes after the single discharge, the functional recovery was achieved and the membranous sacs had disappeared; but the levels of acetylcholine, ATP and creatine phosphate were still not restored.     

Stiffness of carbodiimide-crosslinked glycerinated muscle fibres in rigor and relaxing solutions at high salt concentrations

Summary In this article, we have applied a crosslinking technique with a water-soluble carbodiimide to single glycerol-extracted muscle fibres from the rabbit. We have measured the stiffness of the fibres in a relaxing solution at high salt concentration. These fibres were crosslinked to varying extents in the rigor state. The relaxing solution caused uncrosslinked crossbridge heads (S1) to detach. High salt concentrations were used because the fibres were not activated by the crosslinked crossbridges under these conditions, although they were at physiological ionic strength. We found (1) a linear correlation between the extent of S1 crosslinking to thin filaments and the stiffness and (2) that the stiffness in the relaxing solution of muscle fibres with all the S1 heads crosslinked to thin filaments was the same as the rigor stiffness of the fibres before crosslinking. We conclude that the sarcomere compliance is mostly a property of the crossbridges (with more than 65% of the crossbridge compliance in the S1 portions and less than 35% in the S2 portion) and little of other sarcomere structures. In an earlier paper [Kimura & Tawada,Biophys. J. 603–10 (1984)], we demonstrated that the S2 portion of the crossbridge was stiff. It then follows that the crossbridge compliance, and thus the sarcomere compliance, is a property of the S1 heads. Assuming that the S1 portion of the crossbridges in rigor strained muscle fibres is bent, we calculated the Young's modulus of the S1 portion and found that it is about 10² MN m^–2. Because this order of magnitude is reasonable in terms of globular protein elasticity, bending is likely to be the nature of the S1 compliance in rigor muscle fibres.     

不同交联密度甲基丙烯酰酯明胶/脱细胞半月板细胞外基质复合水凝胶的性能

文题释义：脱细胞半月板细胞外基质：由新鲜半月板组织通过湿法差速离心方法脱细胞制备而来,在去除了异体半月板的免疫原性的同时,仍保留了组织的大部分成分和组织本身的生物学性能,例如影响细胞的活性、调控细胞的增殖和分化、促进组织再生和修复等。 甲基丙烯酰酯明胶：是一种明胶的衍生物,由甲基丙烯酸酐与明胶合成而来。在加入光引发剂的基础上经紫外线照射,明胶链上的甲基丙烯酰胺和甲基丙烯酸甲酯侧基聚合形成聚合物链,聚合物链交错纵横,最终形成网状结构。 交联密度：通常用来表征交联聚合物里交联键的数量,主要受交联时间和交联光强度的影响,其可明显改变聚合物链的形成情况。 背景：交联后的聚合物链对水凝胶的基本性质和细胞相容性存在显著影响,而交联密度可明显改变聚合物链的形成情况,有关交联密度对水凝胶性能影响的针对性研究较少。 目的：制备一种细胞相容良好性的复合水凝胶,探究交联密度对该水凝胶性能的影响。 方法：配制甲基丙烯酰酯明胶溶液,然后加入脱细胞半月板细胞外基质溶液与LAP溶液,制备预凝胶溶液,采用蓝光对溶液进行交联,交联时间分别为10,30,60 s,检测3种水凝胶的压缩弹性模量、溶胀倍率与降解性能。将半月板纤维软骨细胞加入预凝胶溶液中,采用蓝光对溶液进行交联,交联时间分别为10,30,60 s,检测培养对应时间的细胞活性、形态与聚集。 结果与结论：①交联60 s水凝胶的压缩模明显高于交联10,30 s的水凝胶(P < 0.05);②交联10 s水凝胶的溶胀倍率明显高于交联30,60 s的水凝胶(P < 0.05),交联30,60 s的水凝胶的溶胀倍率比较差异无显著性意义(P > 0.05);③随着交联时间的延长,水凝胶的降解时间延长,交联60 s的水凝胶需要80 min完全降解,交联10 s的水凝胶50 min就可以完全降解;④培养24 h后,3组水凝胶中的细胞活性均在95%以上,各组之间无差异(P > 0.05);⑤培养1 d时,3组水凝胶中的细胞均呈球形且均匀分布;4 d时,3组细胞均开始伸展,交联10 s水凝胶中有较小的细胞团;7 d时,3组细胞树突状伸展更为明显,其中交联10 s水凝胶中形成了较为明显的细胞团;⑥培养1,7,14 d时,交联10 s水凝胶中的细胞活性均在85%以上。培养1 d时,交联10 s水凝胶中的细胞呈球形分布,且分布均匀;培养28 d时,细胞呈树突状伸展,并聚集形成网状结构;⑦结果表明,甲基丙烯酰酯明胶/脱细胞半月板细胞外基质复合水凝胶的性能可通过调整交联密度进行优化。 ORCID: 0000-0002-3606-1097(周建) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

不同程度失神经支配后面神经眼支和口支超微结构变化的实验研究

目的探讨不同程度失神经支配后面神经眼支和口支的超微结构变化。方法建立豚鼠右侧面神经阻断15 s、30 s和切断的动物模型。于术后1周和1个月切取面神经眼支和口支,应用半薄切片和超薄切片在光镜和电镜下观察面神经眼支和口支的病理变化,探讨失神经支配后面神经眼支和口支病理变化过程及两者差异。结果光镜下半薄切片测定面神经眼支和口支的直径,正常情况下,面神经眼支直径大于口支直径;当神经受损伤1周时,面神经平均直径变小,眼支始终大于口支。当神经受损伤1个月时,15 s 1个月组面神经口支直径大小有所恢复,接近正常,但眼支恢复较差;30 s1个月组,面神经眼支和口支均没有明显恢复。电镜下面神经眼支和口支不同损伤程度的超微结构比较,当神经受损伤1周时,随着损伤程度加重,电镜下面神经眼支和口支超微结构改变加重,15 s 1周<30 s 1周<切断1周。当损伤1月时,神经功能有一定的恢复,电镜下面神经眼支和口支超微结构损伤减轻,15 s 1周>15 s 1个月,30 s 1周>30 s 1个月;眼支大于口支,面神经口支较眼支易恢复。面神经切断组,神经远端没有任何恢复,病变程度加重。结论面神经眼支直径大于口支,面神经眼支较口支易受损伤,且较口支不易恢复,面神经受压榨时间越长,损伤越重,恢复越差。     

活化的巨噬细胞在体内对成年大鼠视神经夹伤后视网膜神经节细胞的保护作用

目的:评估活化的巨噬细胞对于视神经损伤后视网膜神经节细胞存活的影响。 方法:成年Wistar大鼠随机分为2组，A组左眼为正常对照组，右眼为单纯视神经夹伤组；B组按夹伤后眼内注射药物不同，每只大鼠右眼为酵母多糖组，左眼为PBS组。采用双上丘和外侧膝状体注射3%荧光金标记双眼视网膜神经节细胞7 d后，除正常对照组外均应用40 g力的视神经夹在大鼠眼球后2 mm处夹视神经9 s，观察视神经夹伤后不同时间，视网膜神经节细胞存活数。视网膜进行ED-1染色以鉴定是否有巨噬细胞被激活。 结果:正常对照组、视神经夹伤组及PBS组中未见ED-1阳性巨噬细胞，酵母多糖处理组中在视网膜表面可见ED-1阳性巨噬细胞。正常对照组及视神经夹伤对照组RGC逆行标记3、7、14、21 d细胞数不同。视神经夹伤组被标记的RGC分别相当于正常对照组的92.6%、82.9%、69.6%、57.6%。酵母多糖治疗组在夹伤后3、7、14、21 d标记的RGC数分别相当于正常对照组的99.6%、89.2%、72.6%、62.6%，均显著高于视神经夹伤组。 结论:玻璃体内注射酵母多糖可激活巨噬细胞，激活巨噬细胞可以促进视神经损伤后视网膜神经节细胞的存活。     

阑尾手术中所见的阑尾形态及其临床意义

术中对137例阑尾炎患者的阑尾进行了观察。游离型阑尾占90.6%,非游离型8.0%,畸型1.4%。阑尾可概分为7种形态,以直形、半月形、钩形为多见。阑尾的平均长度7.1cm。71.6%的阑尾体表投影在麦氏点与兰氏点之间。