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61.
目的:探讨颈前路椎体次全切治疗颈椎后纵韧带骨化的手术减压范围。方法:采用前路椎体次全切植骨融合术治疗颈椎后纵韧带骨化56例,其中完全切除骨化者47例,用“漂浮法”处理者9例,并针对不同个体及病变特点采用不同的减压范围。结果:54例获得3个月-6a随访,平均28个月。植骨均于术后3-5个月内获得骨性融合。JOA评分由术前8.5分提高到术后14.1,平均改善率74%,优良率80.2%。结论:行椎体次全切术治疗颈椎后纵韧带骨化时应针对不同个体及病变特点采用不同的足够的减压范围,可以减少并发症,并获得较佳的疗效。  相似文献   
62.
后鼓室颞骨切片与CT对照研究   总被引:4,自引:1,他引:4  
目的:为后鼓室及耳科病变的影像诊断和手术治疗提供解剖学基础。方法:l5例成人头部标本,以眦耳线(cML)为基线,获得间隔为1.00mm,厚度为1.00mm的CT图像,扫描后的头部标本按原定位截取以耳颞区为中心的组织块并将其制成厚为1.00mm的连续横断薄层切片。标本切片与CT图像对照,对颞骨内砧骨窝、鼓索隆起、茎突隆起、面神经隐窝、鼓室窦、岬小桥、外耳道上棘等结构进行观察。结果:砧骨窝深度为1.49mm,至面神经锥曲的距离为5.67mm。后鼓室窦内侧壁至面神经水平部的距离为3.14mm。外耳道上棘至面神经垂直段、鼓索神经、鼓岬的距离分别为16.76mm、15.94mm和21.81mm。结论:耳颞区断面标本与CT图像进行对照研究,其结果对耳科疾病的影像诊断及手术治疗具有参考价值。  相似文献   
63.
垂体后叶是重要的神经内分泌器官。对于垂体后叶的形态和功能研究是神经科学研究的热门课题。但以往对垂体后叶的研究大都是以大鼠、兔等低等动物为材料,而动物种间的差异很大。仅以大鼠等啮齿动物的资料为根据难以得出全面的解释。为此,作者对包括人、恒河猴在内的多种哺乳动物的垂体后叶内13种神经活性物质的分布进行了比较研究,得到了较为全面的资料。还发现2种新的神经纤维也存在于哺乳动物垂体后叶。本文用免疫组织化学方法证明了P物质免疫反应神经纤维不但存在于大鼠垂体后叶,也存在于人、猴、狗和猫的垂体后叶。比较五种动物垂体后叶P物质免疫反应神经纤维的密度,以狗垂体后叶为最高,人和大鼠次之,猴垂体有稀疏的分布,猫垂体后叶密度最低。在人和猴垂体后叶,P物质免疫反应神经纤维主要分布在垂体柄、神经叶的中央部和腹后部,其它部位仅见散在纤维。在狗垂体后叶背部和漏斗壁可见非常密集的纤维网,腹后部仅见中等密度P物质阳性纤维。猫漏斗壁的纤维束为中等密度,并沿漏斗隐窝壁直达漏斗隐窝底壁,其它部位仅见稀少的阳性纤维。大鼠垂体后叶周边部纤维密度高于中央区,吻侧端又稍多于尾侧端。  相似文献   
64.
The anterograde and retrograde transport of wheat germ agglutinin congugated to horseradish peroxidase was used to examine the laminar organization of cortical connections with the two visual zones that comprise the cat's lateral posterior nucleus. Microelectrophoretic deposits of the tracer into the principal tecto-recipient zone in the medial division of the lateral posterior nucleus revealed reciprocal connections with the following cortical fields: areas 19 and 21a, the medial and lateral banks of the middle suprasylvian sulcus, and the dorsal and ventral banks of the lateral suprasylvian sulcus, which correspond to the dorsal lateral suprasylvian and ventral lateral suprasylvian visual areas of Palmer et al. [(1978) Brain Res. 177, 237-256] and an area in the fundus of the posterior suprasylvian sulcus. In each of these cortical areas two distinct populations of cells were labeled, small pyramidal neurons in layer VI and large pyramidal cells in layer V. Overlying these backfilled cells were two bands of anterograde label, a narrow strip in layer I and a wide band centered in layer IV. Deposits of wheat germ agglutinin conjugated to horseradish peroxidase confined to the striate-recipient zone in the lateral portion of the lateral posterior nucleus resulted in cortical label in areas 17, 18, 19, 20a and b, 21a, the medial and lateral banks of the middle suprasylvian sulcus, the posterior suprasylvian sulcus and in the fundus of the splenial sulcus. In all cortical areas other than 17 and 18, the laminar distribution of label was the same as that found after deposits of the tracer into the medial division of the lateral posterior nucleus. In contrast, areas 17 and 18 contained backfilled cells that were confined to layer V and anterograde label that was restricted to layer I. These findings indicate that the cortical areas that receive a direct projection from the A laminae of the dorsal lateral geniculate nucleus maintain a distinct laminar organization of reciprocal connections with the extrageniculate visual thalamus. Conversely, all other visual areas of the cortex share a common pattern of reciprocal connections with both the tecto- and striate-recipient zones of the lateral posterior nucleus.  相似文献   
65.
Summary The lateral posterior-pulvinar (LP-P) complex of mammals receives a major input from the superior colliculus (SC). We have studied the response properties of LP cells and investigated the effects of reversible inactivation of the colliculus on the visual responses of LP units in anesthetized and paralyzed rabbits. Cells in LP had large receptive fields responsive to either stationary or moving stimuli. One third of the motion-sensitive cells were direction selective. The size of the receptive fields increased with eccentricity and there was a retinotopic organization along the dorso-ventral axis. Comparison of the LP and superior colliculus properties revealed substantial differences in visual response characteristics of these two structures such as the size of the receptive fields and the number of direction-selective cells. Electrical stimulation of the LP evoked antidromic action potentials in tectal cells that were motion sensitive. We found a dorsoventral gradient in the projections of collicular cells. Units located more dorsally in the colliculus sent their axons to LP while cells lying more ventrally sent axons toward the region lying posterior to LP. A micropipette filled with lidocaine hydrochloride was lowered into the superficial layers of the superior colliculus in order to reversibly inactivate a small population of collicular cells. Rendering the superior colliculus inactive produced a sharp attenuation of visual responses in the majority of LP cells. Some neurons ceased all stimulus-driven activity after collicular blockade while a few cells exhibited increased excitability following collicular inactivation. These experiments also indicate that the tecto-LP path is topographically organized. An injection in the colliculus failed to influence the thalamic response when it was not in retinotopic register with the LP cells being recorded. Our results demonstrate that the superior colliculus input to LP is mainly excitatory in nature.  相似文献   
66.
本文使用条件—检验刺激技术,研究了电刺激杏仁皮质内侧核对猫丘脑后核内脏大神经诱发放电的影响。电刺激杏仁皮质内侧核抑制丘脑后核的中等和长潜伏期内脏大神经诱发放电呈现两种形式:即时抑制和迟发抑制。前者可能是通过从杏仁核到丘脑后核的神经通路产生的,静脉注射纳洛酮可消除这种抑制,提示有鸦片样物质的参与。后者可能涉及神经—体液性因素。结果提示,杏仁核参与抑制内脏痛。  相似文献   
67.
侧块钢板螺钉系统在颈椎后路手术中的应用   总被引:2,自引:1,他引:1  
目的 探讨侧块钢板螺钉系统在颈椎后路手术中应用的临床经验。方法 对1999年2月-2000年3月间共36例行侧块钢板内固定的患者进行回顾分析。29例(80.6%)获得随访,平均随访时间8个月(4-15个月)。29例患者中颈椎病(3节及3节段以上椎间盘突出)20例,黄韧带骨化症(OYL)1例,后纵韧带骨化症(OPLL)2例,颈椎骨折脱位6例。手术时采取坐位,病变节段行全椎板切除减压,保留关节突。钢板螺钉固定于侧块(即关节突),同时关节突间植骨融合。结果 29例患者共植入124枚螺钉,平均每位患者4.3枚。颈痛明显改善者为18例(20例术前存在颈痛)占90%。术后3-6月X线随访,27例患者关节突间见骨小梁生成,融合率93%。4例患者路侧块钢板螺钉系统能提供较稳定的固定,有效改善颈痛。钢板螺钉松动与神经根损伤是较严重的并发症。只要严格掌握手术适应证与安装技术,颈椎后路钢板固定是治疗颈椎不稳的一种十分有效的方法。  相似文献   
68.
BackgroundIt has been hypothesized that increasing posterior tibial slope can influence condylar rollback and play a role in increasing knee flexion. However, the effects of tibial slope on knee kinematics are not well studied. The objective of this study is to assess the effects of tibial slope on femorotibial kinematics and kinetics for a posterior cruciate retaining total knee arthroplasty design.MethodsA validated forward solution model of the knee was implemented to predict the femorotibial biomechanics of a posterior cruciate retaining total knee arthroplasty with varied posterior slopes of 0°-8° at 2° intervals. All analyses were conducted on a weight-bearing deep knee bend activity.ResultsIncreasing the tibial slope shifted the femoral component posteriorly at full extension but decreased the overall femoral rollback throughout flexion. With no tibial slope, the lateral condyle contacted the polyethylene 6 mm posterior of the midline, but as the slope increased to 8°, the femur shifted an extra 5 mm, to 11 mm posterior of the tibial midline. Similar shifts were observed for the medial condyle, ranging from 7 mm posterior to 13 mm posterior, respectively. Increasing posterior slope decreased the posterior cruciate ligament tension and femorotibial contact force.ConclusionThe results of this study revealed that, although increasing the tibial slope shifted the femur posteriorly at full extension and maximum flexion, it reduced the amount of femoral rollback. Despite the lack of rollback, a more posterior location of condyles suggests lower chances of bearing impingement of the posterior femur and may explain why increasing slope may lead to higher knee flexion.  相似文献   
69.
Study Design: Systematic review and meta-analysis.Objective: To compare the effectiveness and safety between anterior and posterior approach, and determine the best surgical methods for the treatment of ossification of the posterior longitudinal ligament (OPLL) in the cervical spine.Methods: We searched the Cochrane Library, PubMed, CNKI and Wanfang Med Data databases from January 2007 to March 2018. Japanese Orthopaedic Association (JOA) scores, cervical lordosis, functional recovery rates, excellent and good outcomes of the surgical approaches, and complication and reoperation rates were analyzed. RevMan 5.3 was utilized for data analysis.Results: Eleven studies were included in the meta-analysis. By comparing the anterior and posterior approaches for the treatment of OPLL in the cervical spine, statistically significant differences were found in the preoperative initial JOA, the postoperative final JOA scores, functional recovery rates, complication rates, excellent and good outcomes of the surgical approaches and reoperation rates. However, no statistically significant difference in the occurrence of the preoperative and postoperative cervical lordosis was noted.Conclusion: The anterior approach is superior to the posterior approach in terms of the postoperative final JOA score, functional recovery rate, and clinical outcomes. Although the complication and reoperation rates of the anterior approach are higher than those of the posterior approach. We recommend the anterior approach for the treatment of OPLL when patients with occupying ratio ≥ 60%. In addition, high-quality studies with long-term follow-up and large sample size are also needed.  相似文献   
70.
目的探究人文医疗在阴式全子宫切除术联合阴道后壁修补术治疗老年子宫脱垂合并肠疝(阴道后壁膨出)患者中的应用效果。方法选择2018年1月至2019年12月期间天长市中医院收治子宫脱垂合并肠疝患者120例作为研究对象。全部入选病例均行阴式全子宫切除术联合阴道后壁修补术治疗,采用随机数字表法将病例分为对照组和观察组,各60例。对照组给予常规护理,观察组给予人文医疗护理。对比2组患者中文版知觉压力量表(CPSS)评分、抑郁自评量表(SDS)、焦虑自评量表(SAS)评分、心理弹性量表-简表(RS-14)、护理服务满意度、皮质醇(Cor)、心率及平均动脉压。结果护理前,2组CPSS、SDS、SAS及RS-14评分组间比较的差异无统计学意义(P>0.05);护理7 d后,2组CPSS、SDS、SAS及RS-14评分均较护理前降低,且观察组均低于对照组,差异有统计学意义(P<0.05)。观察组患者的满意度(96.67%)较对照组高(80.00%),差异有统计学意义(P<0.05)。观察组手术结束时2组患者的Cor、心率及平均动脉压较对照组低,差异有统计学意义(P<0.05)。结论人文医疗应用于子宫脱垂合并肠疝患者护理中,能够改善其不良情绪,缓解心理压力,减少手术的应激反应,提高患者对护理满意度。  相似文献   
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