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71.
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres.  相似文献   
72.
Summary In decerebrate, unanesthetized cats, the brain stem was longitudinally cut at the midline from its dorsal to ventral surface with the cerebellum kept intact, eliminating neural interactions between the bilateral vestibular nuclei through the brain stem.Extracellular spike potentials of vestibular type I neurons identified by horizontal rotation were distinctly inhibited by contralateral vestibular nerve stimulation. This crossed inhibition was abolished by removal of the medial part of the cerebellum, indicating that the inhibition was mediated through the cerebellum. Neither aspiration of the flocculus on the recording side nor intravenous administration of picrotoxin eliminated transcerebellar crossed inhibition, suggesting that it is mediated through the cerebellar nuclei. When the fastigial, interposite and dentate nuclei were stimulated, inhibition of vestibular type I neurons was produced only from the contralateral fastigial nucleus. Cerebellocortical stimulation which inhibited fastigial type I neurons suppressed transcerebellar crossed inhibition. Effective sites for suppression of transcerebellar crossed inhibition were localized to lobules VI and VIIa in the vermal cortex on the side of labyrinthine stimulation.Intracellular recordings were made from type I neurons in the medial vestibular nucleus. Stimulation of the contralateral vestibular nerve and the contralateral fastigial nucleus produced IPSPs in these neurons with the shortest latency of 3.8 msec and 1.8 msec, respectively. The difference between these two latency values approximates the shortest latency of spike initiation of fastigial type I neurons in response to vestibular nerve stimulation. It is postulated that transcerebellar crossed inhibition is mediated through the fastigial nucleus on the side of labyrinthine stimulation.  相似文献   
73.
74.
下颌第一前磨牙根管系统和根尖孔解剖及临床意义   总被引:1,自引:0,他引:1  
采用牙髓透明法对 347颗下颌第一前磨牙根管系统的数目和形态进行观察。下颌第一前磨牙根管可分为Ⅰ、Ⅱ、Ⅲ、Ⅳ型。其中Ⅰ型 (单根单管型 )占 83 86 % ,Ⅱ型 (单根双管型 )占 4 6 1% ,Ⅲ型 (单双管混合型 )占 11 2 4 % ,Ⅳ型 (双根双管型 )占 0 2 9%。应用XTT— 3A连续变倍体视显微镜对 347颗下颌第一前磨牙的根管系统形态进行观察 ,根尖分歧出现率 15 6 3% ,根尖分叉出现率 2 4 3% ,根管侧支出现率 1 0 8%。并对 347颗下颌第一前磨牙的根尖孔与根尖顶的位置关系进行观察 ,根尖孔位于根尖顶者占 88 14 % ,位于旁侧者占 11 86 %。并就上述内容的临床意义进行了讨论。  相似文献   
75.
颞骨内面神经管的解剖测量及其临床意义   总被引:3,自引:0,他引:3  
目的为避免中耳手术中对面神经的损伤。方法对50例(100侧)成人尸头颞骨内面神经管进行解剖测量。结果面神经管迷路段为4.53±1.21mm,鼓室段为9.32±1.25mm,乳突段为13.25±1.53mm,面神经管总长为29.86±0.57mm。结论熟悉颞骨内面神经管的解剖结构,可避免对面神经的损伤,减少和避免面瘫的发生。  相似文献   
76.
The present work comprises a longitudinal study of Schistosoma mansoni infection in occupationally hyper-exposed canal cleaners in the Sudan and the influence of chemotherapy on humoral immune parameters. The study groups included chronically infected canal cleaners (n = 19), newly recruited canal cleaners (n = 17), normally exposed adults (n = 31), school children (n = 46) and Sudanese negative controls (n = 48). Previous studies of the same canal cleaners have demonstrated that chronically infected canal cleaners were more resistant to reinfection than newly recruited canal cleaners. ELISA was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection was correlated with IgE antibody response, the resistant group of canal cleaners (those who stopped passing ova after treatment) showed a significant positive correlation between intensity of infection and specific IgE to WWH (Spearman''s correlation coefficient = 0·49, P < 0·05) compared with a highly significant negative correlation in the susceptible group (acquired new infection after treatment, Spearman''s correlation coefficient = 0·94, P < 0·01). Normally exposed adults and school children had significantly less specific IgE to WWH than canal cleaners, while chronically infected canal cleaners had significantly higher levels of specific IgG1 to WWH than newly recruited canal cleaners and school children, and significantly higher levels of specific IgG4 to WWH than school children. There was a significant increase in specific IgG1 and IgG4 to WWH, 3 months after treatment, in newly recruited canal cleaners and a significant decrease, 1 year after treatment, in normally exposed adults. None of the groups studied after treatment showed a significant change in their specific IgE to WWH. Normally exposed adults had significantly lower levels of specific IgE to SEA than newly recruited canal cleaners, and significantly lower levels of specific IgG1 to SEA than other infected groups. Both newly recruited canal cleaners and school children had significantly higher levels of specific IgG2 to SEA than persons in other groups. Only small differences between groups were observed with regard to specific IgG3 and IgM to SEA. Specific IgG4 to WWH and SEA showed different patterns after treatment between the resistant and susceptible groups of canal cleaners. The resistant group maintained the same level of IgG4 to WWH after treatment compared with a significant increase in the susceptible group. On the other hand, levels of specific IgG4 to SEA showed a highly significant decrease after treatment in the resistant group. In contrast, the same antibody subclass increased after treatment in the susceptible group. Generally, results show an association between IgE and IgG1 responses to WWH and resistance to reinfection. In contrast, an association was observed between IgG2 and IgM responses to SEA and susceptibility to reinfection.  相似文献   
77.
The ophthalmic artery and its branches,measurements and clinical importance   总被引:5,自引:0,他引:5  
Summary Seventy-one Caucasian orbits (36 right, 35 left) were studied by dissection. The diameter of the ophthalmic a. (2 mm from the origin) was 1.54 ± 0.04 mm (male) and 1.31 ± 0.05 mm (female). In individual cases, there were no significant differences in vessel diameter between the right and left sides but, differences in vessel diameter between males and females were more commonly observed in the arteries which leave the orbit (extraorbital group), the individual vessels having a larger diameter in males. The incidence of the ophthalmic a. passing in the orbit medially under the optic n. was 18.6%. The lacrimal a. was observed to arise from the ophthalmic a. in only 82.5% of the cases examined, 15.9% of the cases showed the origin to be at the anastomotic branch of the middle meningealThis article is dedicated to Pr Dr Hoepke on occasion of his 100th birthday  相似文献   
78.
在80侧成人颞骨干标本上,对面神经锥体段的埋藏位置及深度,面神经与面神经隐窝、鼓室窦三者之间的关系及其变异类型进行了应用解剖学研究。提出了耳科后鼓室进手术路中对面神经锥体段的予测方法。经90例手术验证有实用价值。  相似文献   
79.
Summary Unit activites of secondary vestibular neurons that selectively responded to stimulation of the anterior semicircular canal nerve (ACN) were recorded extracellularly in the anesthetized cat. Axonal pathways and projections in the spinal cord of the ACN-activated neurons were examined by recording their antidromic responses to stimulation of the lateral and medial vestibulospinal tracts (LVST and MVST), and the bilateral neck extensor motoneuron pools in the C1segment (C1dorsal rami [DR] motoneuron pools). In order to determine whether the neurons had ascending axon collaterals to the extraocular motoneurons, the contralateral (c-) inferior oblique (IO) motoneuron pool was also stimulated. Twenty-seven neurons sent their axons to the ipsilateral (i-) C1DR motoneuron pool via the LVST without any projection to the extraocular motoneuron pool. All the cells except one were located in the ventral part of the lateral vestibular nucleus. This pathway produced monosynaptic EPSPs with short time-to-peak and short half-width in C1DR motoneurons (16/16 motoneurons). Eight neurons sent axons to the i-C1DR motoneuron pool via the MVST without any to the extraocular motoneuron pool. Cell somata were located in the descending nucleus or in the ventral part of the lateral nucleus. These neurons did not produce postsynaptic potentials (PSPs) in any C1DR motoneurons. All thirty-five neurons sending axons to the c-C1DR motoneuron pool have ascending axon collaterals to the c-IO motoneuron pool.  相似文献   
80.
舌下神经管及其毗邻结构的显微解剖和临床意义   总被引:2,自引:0,他引:2  
目的:研究舌下神经管及其毗邻结构的显微解剖,为舌下神经管疾病的影像学诊断和手术入路的选择提供形态学数据。方法:肉眼和手术显微镜下观测30例(60侧)成人头颅干骨标本的舌下神经管及其毗邻结构。结果:舌下神经管位于枕骨髁的前上方,为一对卵圆形或圆形孔道,内口至外口的长度(8.51±0.91)mm。舌下神经管内口呈双管者5侧(8%);内口后缘与枕骨髁后缘的距离(10.07±0.75)mm,外口后缘至枕骨髁后缘(14.22±1.18)mm。左、右侧枕骨髁的前后径分别为(23.10±1.57)mm、(22.38±2.28)mm。结论:熟悉舌下神经管及其毗邻结构的解剖有利于相关疾病的影像诊断和手术入路的选择。  相似文献   
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