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41.
结缔组织生长因子在椎间盘纤维化和退变中的表达和作用   总被引:1,自引:0,他引:1  
目的研究疼痛椎间盘组织中结缔组织生长因子(connective tissue growth factor, CTGF)的表达及其在椎间盘纤维化和退变中的作用。方法收集腰椎后路融合过程中切除的43个疼痛的病理椎间盘,来自于28例行腰椎后路椎体间融合手术的严重椎间盘源性下腰痛患者;同时收集16个在MRIT2加权像信号强度明显减弱的无腰痛症状的退变椎间盘,取自于6例腰椎管狭窄症和8例多节段腰椎后路融合的患者(年龄44~75岁,平均53.5岁,男女比例为8:6)和8个正常对照椎间盘,来自于4具新鲜尸体标本(22~39岁,平均28岁)的L。和蛉.椎间盘。均行组织学检查并用免疫组化方法检测CTGF在不同椎间盘组织的表达。结果组织学检查发现,疼痛椎间盘组织显示不同程度的慢性血管化炎症反应。纤维环组织失去正常的胶原纤维板层结构,板层结构断裂、紊乱或相互交叉融合,正常的成纤维细胞被软骨细胞替代。髓核显示明显纤维化、血管浸润或形成炎性肉芽组织,软骨细胞被成纤维细胞所替代。免疫组化染色显示CTGF在疼痛椎间盘大量表达,无腰痛症状的退变椎间盘有少量表达,正常对照椎间盘没有表达。结论疼痛的退变椎间盘在组织学上明显不同于无腰痛症状的退变椎间盘。CTGF在疼痛椎间盘的大量表达可能与椎间盘纤维化和退变过程密切相关。  相似文献   
42.
目的探讨腰椎终板Modic改变在腰腿痛病例中的的临床分布特点,并探讨发生Modic改变的相关因素。方法选择2005年一年内因腰痛或坐骨神经痛行腰椎MR检查和常规X线检查的患者1223例,分析腰椎MRI中终板Modic改变在椎间盘节段、年龄和椎间盘退变分类中的分布特点及其相关因素。结果1223例6115个腰椎椎间盘中,257例(21.0%)320个椎间盘(5.2%)邻近终板发生M0dic改变,其中Ⅰ型48例(3.9%)51个椎间盘(0.8%),Ⅱ型206例(16.8%)266个椎间盘(4.3%)、Ⅲ型3例(0.2%)3个椎间盘(0.05%)。椎间盘节段L5S1 168个、L4-5 95个、L3-4 29个、L2-3 18个、L1-2 10个,发生率分别为13.7%、7.8%、2.4%、1.5%、0.8%。突出、脱出和滑脱病例发生率较高(辟0.00)。女性发生率高于男性(P=0.005)。40岁以上是Modic改变发生较多的年龄段(P=0.001)。椎间盘退变程度、椎间盘节段与年龄均和Modic改变具有显著相关性(P=0.000)。回归方程为Y=-5.955+0.198A+1.528L+1.883D(Y为M0dic改变,A为年龄,L为椎间盘节段,D为椎间盘退变程度),P=0.000,EXP值:D=6.571,L=4.609,A=1.220。结论腰椎终板Modic改变和椎间盘退变、椎间盘节段和年龄之间存在相关关系,椎间盘退变是最重要的影响因素。Modic改变Ⅱ型最多,Ⅰ型次之,Ⅲ型最少;多发生于L4-5和L5S1椎间盘节段;女性高于男性;40岁以上是易发年龄。  相似文献   
43.
回顾5例由于神经根变异或特殊类型椎间盘突出引起的腰腿痛病人,对其病理及术中处理做了介绍,认为由于神经根的解剖变异,更容易受到椎间盘突出的卡压。手术中如临床症状符合椎间盘突出症,而预定探查间隙未发现突出物,或与临床症状不符者,应根据神经根激惹及松紧程度,扩大探查范围,查明造成疼痛的原因,避免二次手术。  相似文献   
44.
For substances eliminated from blood by the liver, the effect of a change in unbound fraction of drug (fu b )on steady state total (C b )and unbound (Cu b )blood concentrations has hitherto only been considered for the two limiting cases, i.e., at the upper and lower extremes of hepatic intrinsic clearance (CL int ).For a substance of very low CL int ,if fu b changes, C t will change and Cu b will remain constant, whereas if CL int isvery high, Cu b will change and C b will remain constant.The present study defines the effects of a change in fu b on C b and Cu b over the whole CL int range. Computer simulations were undertaken which predicted that, for a given change in fu b ,absolute and relative changes in C b would decreasenonlinearly with increasing CL int, twhile the relative change in Cu b would increasewith CL int .The absolute change in Cub would be independent of CL int .Significant changes in Cb and Cu b would be observed at intermediate values of CL int not just at the high and low extremes. These theoretical predictions were investigated experimentally in the isolated perfused rat liver by examining the effects of a change in fu b of sodium taurocholate a substance with intermediate CL int (such that at fu b =0.27,hepatic extraction ratio=0.71) induced by concurrent administration of sodium oleate. Sodium 24- 14 C-taurocholate (specific activity 52 Ci/mmol) was infused into the reservoir in a recycling system at 30 mol/hr for 105 min (n=6). At 45 min a bolus dose of sodium oleate (50 mmol) was administered to the reservoir, followed by a constant infusion of 143 mmol/hr for 1 hr. Following the administration of oleate, taurocholate fu b fell promptly by 55% (0.27–0.12). There was a relative increase of taurocholate C b of 22.7% and a relative decrease in Cu b of 45.4%, in accordance with the simulations (p<0.05). We conclude that important changes in unbound steady-state concentration, the pharmacologically active moiety, can occur upon changes in unbound fraction with compounds of intermediate hepatic intrinsic clearance.This study was supported by the National Health and Medical Research Council of Australia.  相似文献   
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47.
When observers step about their vertical axis ("active turning") without vision they dispose of essentially two sources of information that can tell them by how much they have turned: the vestibular cue which reflects head rotation in space and the "podokinesthetic" cue, a compound of leg proprioceptive afferents and efference copy signals which reflects the observer's motion relative to his support. We ask how these two cues are fused in the process leading to the perception of self-displacement during active turning. To this end we compared the performance of observers in three angular navigation tasks which differed with regard to the number and type of available motion cues: (1) Passive rotation, vestibular cue ( ves) only; observers are standing on a platform which is being rotated. (2) Treadmill stepping, podokinesthetic cue ( pod) only; observers step counter to the rotating platform so as to remain stable in space. (3) Active turning, ves and pod available; observers step around on the stationary platform. In all three tasks, angular velocity varied from trial to trial (15, 30, 60 degrees /s) but was constant during trials. Perception was probed by having the observers signal when they thought to have reached a previously instructed angular displacement, either in space or relative to the platform ("target"; range 60-1080 degrees ). Performance was quantified in terms of the targeting gain (displacement reached by the observer divided by target angle) and of the random error ( E(r)), which records an observer's deviation during single trials from his average performance. Confirming previous observations, E(r) was found to be significantly smaller during active turning than during passive turning, and we now complement these observations by showing that it is also significantly smaller than during treadmill stepping. This behaviour of E(r) is compatible with the idea that ves and pod be averaged during active turning. On the other hand, the observed characteristics of the targeting gain ( G(T)) support this idea only for the case of fast rotations (60 degrees /s); at lower velocities, the gain found during active turning was clearly not the average of the G(T) values recorded in the passive and the treadmill modes. We therefore also discuss alternative scenarios as to how ves and pod could interact, among these one based on the concept of a vestibular eigenmodel. A common denominator of these scenarios is that ves assumes the role of a prerequisite for an optimal use of pod during turning on a stationary support, without itself entering the calculation of displacement perception; this perception would be based exclusively on pod. Finally, it was a consistent observation that during passive rotations cognitive mechanisms fill in for the decaying vestibular signal in the context of the present navigation task, enabling observers to achieve large displacements surprisingly well although the duration of these movements exceeds by far the conventionally cited value of the central vestibular time constant (=20 s).  相似文献   
48.
Coxsackievirus B is the most common cause of viral myocarditis and is particularly virulent in neonates and children. Adenovirus is also a leading cause of the disease. The determinant of tropism for both viruses is considered to be the expression of coxsackievirus and adenovirus receptor (CAR) in target organs. However, developmental change and physiological localization of CAR in the heart are unknown. We examined expression levels of CAR in rat hearts by quantitative real-time polymerase chain reaction and Western blot analysis and found that CAR decreased gradually during postnatal development, although CAR was detectable, even in adults. Immunohistochemistry revealed CAR on the whole surface of cardiomyocytes in immature rat hearts. In contrast, CAR was detected predominantly on intercalated disks in the adult heart and was accumulated especially at the contact point between the cultured cardiomyocytes, even though they were prepared from the neonatal rat heart. In conclusion, CAR was expressed abundantly on the whole surface of cardiomyocytes in immature rat hearts. Both the expression level and the localization of CAR are possible determinants of the susceptibility to viral myocarditis of neonates and children.  相似文献   
49.
三维超声心动图技术能使医生直观地看到心脏整体和各部分的运动,在临床得到重视。在三维超声心动图技术中,如何定量的描述心脏中某个组织的运动状况极具临床意义。本研究提出了一种基于椭圆偏微分方程的二尖瓣三维运动估计方法。该方法直接在三维超声图像的位移场上进行了运动估计,避免了传统运动估计方法,如光流法,需要标定的缺点。本研究首先建立一个二次误差指标函数,然后利用变分法导出了三维空间下的一组椭圆型偏微分方程。这类方程有着比较成熟的数值解法,利用了有限差分法,对多个三维超声数据立方体进行了计算,结果证明这类方法是有效的。  相似文献   
50.
经皮穿刺椎间盘髓核摘除术入路的研究   总被引:1,自引:0,他引:1  
为提供椎间盘髓核摘除术形态学依据,在7具成人横断面标本上观察测量了L1~L5椎间盘平面经皮穿刺椎间盘髓核摘除术的进针点、角度和深度。发现在L1~L3、L4~L5椎间盘髓核的穿刺点以距后正中线8~10cm,9~11cm,穿刺角度以46.7°~59.5°,穿刺深度为110.2~128.9mm为最宜。  相似文献   
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