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1.
采用组化特染,透射电镜和图象分析仪观察了35只正常人眼筛板结缔组织的纤维成分和结构形态,根据生物力学原理分析了筛束的力学性质和筛板的结构特征,探讨了筛板的损害形式和在眼压与视神经损害间的中介作用及其影响因素。结果显示,筛束含有细胞间质所有三种纤维,具有弹性、塑性和刚性三重复合性质,筛板纵向椭圆、筛束行径和密度象限性差异及筛板厚度个体性差异等与筛板抗损害性能有关。眼压对筛板作用有两种途径,筛板损害是  相似文献   
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本文应用Nissl法,Luxol Fast Blue法及Golgi法对猫延髓尾段背角(三叉神经脊束核尾侧亚核)第Ⅴ层进行了系统的细胞构筑学研究。发现此层中含有大、中、小型神经元,其中中型最多,小型次之,大型最少。依树突分支形态及树突棘的多寡,将第Ⅴ层中的神经元分成辐射状和丛状两大类。前者又可分成锥体型、多极型及“双极型”神经元。其中,锥体型与多极型神经元各包括着有棘的及平滑的两类。本文并结合电生理学、细胞内注射技术及HRP追踪技术的研究结果,对第Ⅴ层中神经元的功能进行了探讨。  相似文献   
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Interleukin-10 (IL-10) deficiency in gene knockout mice causes chronic enterocolitis. We hypothesized that inflammation in human inflammatory bowel disease might result from innate alterations in the IL-10 pathway. Serum, supernatants, and mRNA of peripheral blood mononuclear cells (PBMC) and lamina propria mononuclear cells (LPMC) derived from inflamed (LPMC-i) and noninflamed colonic mucosa (LPMC-ni) were collected from patients with Crohn's colitis, ulcerative colitis, and controls. IL-10 protein concentrations and IL-10 mRNA were examined in response to PMA/CD3 or PHA stimulation. The response to rhIL-10 was assessed by inhibition of tumor necrosis factor-alpha (TNF-), IL-6, and interferon-gamma (IFN-) production. Serum IL-10 levels of inflammatory bowel disease (IBD) patients were within the normal range. IL-10 concentrations in supernatants from LPMC-i were significantly lower than from LPMC-ni or PBMC. No difference was seen between samples from ulcerative colitis and Crohn's disease. IL-10 mRNA was detected in 0/4 LPMC-i samples compared to 1/6 LPMC-ni and 6/6 PBMC. RhIL-10 inhibited TNF-, IL-6, and IFN- synthesis in PBMC. This effect was strongly diminished in LPMC. Disease-specific alterations were not detected. Our data suggest that LPMC derived from inflamed colonic mucosa have a reduced ability to produce and to respond to rhIL-10. A disease-specific alteration in the IL-10 pathway, however, was not found.  相似文献   
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4-1BB ligand (L) expressed on antigen presenting cells (APC) interacts with 4-1BB, expressed on activated T cells and this interaction costimulates T cells to secrete cytokines and to proliferate. We investigated whether 4-1BB/4-1BBL interactions might be involved in the pathogenesis of Crohn's disease (CD). In immunohistochemistry, we found 4-1BB expression on lamina propria (LP) cells in inflamed and to a lesser extend in non-inflamed gut tissue from CD patients. mRNA levels for 4-1BB were also elevated in intestinal CD tissue. In contrast, only few 4-1BB-expressing cells were found in inflamed tissue from ulcerative colitis (UC) patients and almost no positive cells were found in control intestinal tissue. 4-1BB expression was better sustained on in vitro activated lamina propria T cells from CD patients compared to controls. Finally, agonistic anti-4-1BB antibody enhanced interferon-gamma (IFN-gamma) production and proliferation of lamina propria T cells from CD patients. Taken together, our data suggest that 4-1BB/4-1BBL interactions contribute to the persistence of gut inflammation in CD.  相似文献   
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采用正常死者眼球和新生血管性青光眼的筛板组织, 研究高眼压对视乳头筛板和结缔组织的作用. 正常眼球12 只, 新生血管性青光眼眼球12 只, 摘除眼球后用10 % 福尔马林溶液固定, 切取视乳头组织约2 m m ×2 mm , 石蜡包埋, 苏木素- 伊红染色, 免疫细胞化学 A B C 法染色. 结果: 正常人筛板的横纵切面具有特定形态, 新生血管性青光眼筛板孔板变形, 筛孔周围结缔组织断裂, 丧失了筛板结构. 结果表明:高眼压下筛孔板和结缔组织的改变, 造成对筛板孔神经纤维的挤压, 阻滞了神经纤维轴浆的运输, 导致神经纤维功能上的损害和相应的视野缺损.  相似文献   
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ObjectivesIrritation fibroma in the oral cavity causes atrophy or squamous epithelium thickening with respect to external injury-associated factors. However, ulcers do not occur in most cases. This study aimed to elucidate the mechanism by which ulcers do not form, focusing on the vascular network in the mucosal epithelium of irritation fibroma.MethodsImmunostaining was performed using an enzyme antibody method with primary antibodies against CD31 and Ki-67 in 17 cases of irritation fibroma in the buccal mucosa. One section was taken at three points from the margin and three points from just above the lesion for measurement. The number of blood vessels in the superficial and deep lamina propria at the measurement site were determined, and the area per blood vessel was measured.ResultsThe number and area of blood vessels in the superficial lamina propria just below the lesion epithelium were smaller than those in the margin. No difference was observed in the number and area of blood vessels in the deep lamina propria between the margins and lesions.ConclusionsOur results suggest that the vascular network in the deep lamina propria is maintained and compensates for the nutrient supply to the covering epithelium.  相似文献   
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BackgroundEvaluation of the lamina terminalis (LT) is crucial for non-invasive evaluation of the CSF diversion for the treatment of hydrocephalus. Together with deep learning algorithms, morphological and physiological analyses of the LT may play an important role in the management of hydrocephalus.AimWe aim to show that exploiting the motion of LT can contribute to the evaluation of hydrocephalus using deep learning algorithms.MethodsThe dataset contains 61 True-fisp data with routine sequences 37 of which are labeled as ‘hydrocephalus’ and the others as ‘normal condition’. A fifteen-year experienced neuroradiologist divided data into two groups. The first group, ‘hydrocephalus’, consists of patients with typical MRI findings (ventriculomegaly, enlargement of the third ventricular recesses and lateral ventricular horns, decreased mamillo-pontine distance, reduced frontal horn angle, thinning/elevation of the corpus callosum, and non-dilated convexity sulci), and the second group contains samples that did not show any symptoms or neurologic abnormality and labeled as ‘normal condition’. The region of interest was determined by the radiologist supervisor to cover the LT. To achieve our purpose, we used both spatial and spatio-temporal analysis with two different deep learning architectures. We utilized Convolutional Neural Networks (CNN) for spatial and Convolutional Long Short-Term Memory (ConvLSTM) models for spatio-temporal analysis using an ROI around LT on sagittal True-fisp images.ResultsOur results show that 80.7% classification accuracy was achieved with the ConvLSTM model exploiting LT motion, whereas 76.5% and 71.6% accuracies were obtained by the 2D CNN model using all frames, and only the first frame from only spatial information, respectively.ConclusionWe suggest that the motion of the LT can be used as an additional attribute to the spatial information to evaluate the hydrocephalus.  相似文献   
10.
Background contextThe dural sac is anchored within the vertebral canal by connective tissue called meningovertebral ligaments in the epidural space. During flavectomy and laminectomy, inadvertent disruption of the dorsal meningovertebral ligaments may lead to dura laceration and cerebrospinal fluid (CSF) leaks. All the described dorsal meningovertebral ligaments were located in the lumbar region. A rare study is available about dorsal meningovertebral ligaments of the cervical spinal dura to the adjacent vertebrae.PurposeTo identify and describe the dorsal meningovertebral ligaments at each cervical level and discuss their clinical significance.Study designA dissection-based study of 22 embalmed cadavers.MethodsThe anatomy was studied in 22 whole cervical cadavers (11 females, 11males), prepared with formaldehyde, whose ages at the time of death ranged from 55 to 78 years. The vertebral canal was divided to expose the dural sac and the spinal nerve roots. At all levels of the cervical vertebra, the morphology, quantity, origin, insertion, and spatial orientation of the dorsal meningovertebral ligaments were determined and the length, width or diameter, and thickness of the ligaments were measured with vernier calipers.ResultsThe dorsal meningovertebral ligaments in the cervical region anchored the posterior dural sac to the ligamentum flavum or laminae. The number of attachment points on the ligamentum flavum was relatively larger than that on the lamina, and the occurrence rate of dorsal meningovertebral ligaments was 100% at C1–C2 and C4––C5. The thickest ligaments were observed at the C1 and C2 vertebrae. The length of the ligaments varied from 1.50 to 35.22 mm, and the orientation of the ligaments mostly was craniocaudal. The morphology of the dorsal meningovertebral ligaments was divided into four types: strip type, cord type, grid type, and thin slice type.ConclusionsIn the cervical spine, the dorsal meningovertebral ligaments exist between the posterior dural sac and the ligamentum flavum or lamina. The dorsal meningovertebral ligaments may be of clinical importance to surgeons. Dissecting the dorsal meningovertebral ligaments before the cervical flavectomy and laminectomy may be an important step in reducing postoperative dura laceration and CSF leaks, which may result in significant benefits for patients and health-care organizations.  相似文献   
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