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91.
我们观察了幼年小白鼠腘淋巴结淋巴窦的超微结构,窦壁由腔面向外一般出3层构成:(1)一层连续的内皮;(2)由一薄层细胞间质构成的基膜;(3)一层外膜网状细胞及其扁平的突起。内皮细胞核扁圆,异染色质细小,核仁不明显,胞质极薄,含粗面内质网极少,而有大量的吞饮小泡。细胞邻接处相互重叠或嵌合,有20nm宽的间隙相隔。有的地方可见不发达的细胞连接。当巨噬细胞或淋巴细胞穿越内皮时,可出现临时性间隙,内皮边缘与穿越细胞相贴。基膜由电子透明的无定形基质及细的胶原原纤维构成。外膜网状细胞的核异染色质较多,核仁明显,胞质丰富,含许多粗面内质网而很少吞饮小泡。外膜网状细胞之间常见0.5μm宽的间隙。在窦腔内有巨噬细胞、淋巴细胞及星状的网状细胞等。由于小白鼠腘淋巴结的淋巴窦小,故窦内星形的网状细胞很少,其超微结构特点,与外膜网状细胞及淋巴组织内的网状细胞相似,在突起的切面上,常见包有小束的胶原原纤维。巨噬细胞较多,形态不规则,常贴附于内皮细胞表面,核椭圆,常有凹陷,胞质丰富,含许多溶酶体。在取材前1h,于足垫注射中国墨汁的小鼠,巨噬细胞吞噬了大量粗的墨汁颗粒。本文认为,淋巴窦壁可能具有一定的屏障作用。 相似文献
92.
93.
对30例成人心标本进行解剖,测得冠状窦口的纵径为17.79±4.66mm,横径为8.75±3.39mm。发现冠状窦口朝向上或水平方向者占70.00%;向下者占30.00%,冠状窦瓣有新月状、半月状、网状、筛状和嵴状等五种形态。瓣高5.31±4.18mm,宽8.62±2.44mm。冠状窦的长度为31.33±10.22mm,最窄径为5.60±1.05mm;并有成角、缩窄和发育不良现象。其属支中有73.33%的心中静脉和10.00%的心小静脉开口于冠状窦口处。本文并就冠状窦心导管术插管的成败因素进行了讨论。 相似文献
94.
目的探讨B超及多排螺旋CT血管造影(CTA)在诊断颈动脉海绵窦瘘中的应用价值。方法分析23例颈动脉海绵窦瘘病例。对受检者行B型超声及颅脑CTA检查,采用容积再现(VR)、最大密度投影(MIP)、多平面重建(MPR)技术处理图像。结果超声可发现增粗的眼上静脉与脉搏同步搏动,并能检测血流频谱,CT检查发现23例均海绵窦扩大.动脉期眼上静脉显影并扩张,8例动脉期大脑中静脉显影并扩张。其中一例同时合并左侧大脑中动脉动脉瘤。结论B型超声及多排螺旋CT血管造影对诊断颈内动脉海绵窦瘘有重要的应用价值。 相似文献
95.
Watanabe A Nagaseki Y Ohkubo S Ohhashi Y Horikoshi T Nishigaya K Nukui H 《Clinical anatomy (New York, N.Y.)》2003,16(1):9-14
The dimensions of the 10 triangles around the cavernous sinus were measured to define the anatomical characteristics of the triangles and to compare their consistency in shape and area. Twelve tissue blocks containing the bilateral cavernous sinuses and medial two-thirds of the middle cranial fossae were obtained from Japanese adults at autopsy, fixed to a stereotactic frame, and examined with an operative microscope. The dimensions of each triangle were measured with calipers and compared, based on the same point and border. The anteromedial triangle and the superolateral (Parkinson's) triangle were more consistent in shape than the paramedial and oculomotor triangles, but the oculomotor triangle was larger in area than these other triangles. The posteromedial (Kawase's) triangle was more consistent in shape and larger than the anterolateral, lateral, and the posterolateral (Glasscock's) triangles. The anteromedial and superolateral (Parkinson's) triangles are important for the combined epi- and subdural approach to cavernous sinus lesions. The posteromedial (Kawase's) triangle is important for gaining access to the posterior cranial fossa from the middle cranial fossa. 相似文献
96.
Ramon Sanchez Richard K. Sibley Juan Rosai Ronald F. Dorfman 《Ultrastructural pathology》1981,2(2):101-119
Eleven cases of sinus histiocytosis with massive lymphadenopathy (SHML) involving lymph nodes were studied electron microscopically. Histiocytes were the most conspicuous element of the infiltrate. They could be divided into small and large forms, although transitions were apparent among them. Most of the small histiocytes were located in the medullary cords. The large histiocytes were predominantly seen within sinuses and were subdivided into two types on the basis of their appearance. The most distinctive feature of these histiocytes was the presence of lymphocytes, plasma cells, and neutrophils within their cytoplasm. Other cells present in the infiltrate were lymphocytes, plasma cells, and occasional neutrophils and mast cells. Blood vessels were prominent throughout. Virus particles, bacteria, and Langerhans granules were consistently absent. No morphologic clues were provided by this study as to the etiology of this disorder. 相似文献
97.
There are two sets of peripheral arterial chemoreceptors in the cat, the carotid bodies innervated by the carotid sinus nerve and the aortic bodies with afferents in the aortic depressor nerves. Reflex stimulation of ventilation in response to hypoxia is abolished acutely after interrupting the sensory pathway from the carotid body chemoreceptors in the cat even though the reflex pathway from the aortic body chemoreceptors is intact. However, in chronically maintained preparations, there is a restoration of the hypoxic response which is mediated by the aortic chemoreflex pathway. It was proposed that restoration was due to a ‘central reorganization’ of chemoreflex pathways which followed interruption of the sensory pathway from the carotid bodies and that the reorganization enhanced the efficacy of the aortic ventilation chemoreflex. This proposal was tested in the present experiments by measuring reflex ventilatory and cardiovascular responses to electrical stimulation of the sensory nerves containing aortic and carotid chemoreceptor afferents following bilateral interruption of carotid sinus nerves and carotid body resection. Responses measured acutely (1–6 h) after interruption were compared with those measured 60–80 and 110–140 days later. At 60–80 days, a chemoreflex response (increase in tidal volume of ventilation) to stimulation of the interrupted carotid sinus sensory pathway was markedly attenuated while the response to stimulation of the uninterrupted pathway in aortic depressor nerves was enhanced. At 110–140 days, the tidal volume response to carotid sinus nerve stimulation was greatly enhanced while the aortic depressor nerve response declined from the elevated level. There were significant but less pronounced changes in the response of other ventilatory and cardiovascular variables to aortic depressor nerve and carotid sinus nerve stimulation.The results support the idea that there is a ‘central reorganization’ of chemoreflex pathways which is reflected functionally by changes in the efficacy of reflexes evoked from aortic depressor nerve and carotid sinus nerve. The changes are analagous to those occurring in somatic reflexes during regeneration of sensory nerves. It is suggested that the changes in efficacy of carotid sinus nerve reflexes are due to a degenerative loss of synapses of the central projections of interrupted carotid sinus nerve sensory axons (degenerative atrophy) and subsequent regenerative like changes (regenerative proliferation) in the central projections. The changes in the efficacy of aortic depressor nerve reflexes may be attributed to formation of new synapses by converging central projections of this uninterrupted pathway (reactive synaptogenesis) and subsequent regression of the newly formed synapses. 相似文献
98.
Piette V Bousquet C Kvedariene V Dhivert-Donnadieu H Crampette L Senac JP Bousquet J Demoly P 《Allergy》2004,59(8):863-868
BACKGROUND: Involvement of paranasal sinuses has been suggested in allergic rhinitis but not clearly demonstrated. AIMS: To investigate the relationship between intermittent allergic rhinitis and computerized tomography (CT). METHODS: Twenty patients with intermittent rhinitis and sensitized to cypress pollens underwent unilateral nasal provocation tests (NPTs) using increasing concentrations of cypress pollens out of the pollen season. Sinus CT-scans were carried out just before a NPT and 24 h later. Nasal lavage was carried out just before a NPT, 30 min after a positive challenge and again 24 h later. Leucotriene C4/D4, intracellular adhesion molecule-1 and eosinophil cationic protein were measured in nasal secretions. RESULTS: Thirteen patients (65%) showed an alteration in their CT-scans after allergen challenge. Ten of them showed sinus changes controlateral to their allergenic provocation. Radiological changes mainly affected the osteomeatal complex and the ethmoid sinuses. Pre-existing abnormalities (13 of 20 cases) mainly concerned the maxillary sinuses. There was no correlation between CT-scan abnormalities and levels of mediators released in nasal secretions. CONCLUSIONS: We have shown that nasal allergen challenge can produce radiological changes in the paranasal sinuses. This mainly concerned the ethmoid sinuses. 相似文献
99.
上矢状窦三维断层解剖及其临床意义 总被引:4,自引:0,他引:4
目的:为给临床影像诊断提供解剖依据,方法:应用24例头部标本研究了上矢状窦的三维断层解剖,结果:在正中矢状断层内,上矢状窦呈前窄后宽的弯曲裂隙,在冠状和横断层中,上矢状窦呈圆形,椭圆形,三角形和楔形,并测量了有关数据,结论:上矢状窦在各断层内的形态与其和人体横断面及冠状面所成的角度有关。 相似文献
100.
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