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91.
Sixteen patients with a megadolichobasilar artery and acute cerebrovascular symptoms are reported. All were explored by computerized tomography and vertebral angiography. Nine had transient ischaemic attacks or definitive ischaemic lesions, whereas 7 had subarachnoid or intracerebral haemorrhage. Among the patients with ischaemic troubles, vertebro-basilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial haemorrhage, 4 had associated aneurysms or arteriovenous malformations, while 3 had subarachnoid or intracerebral haemorrhage with no vascular malformations on the angiograms. The possible relationships between the megadolichobasilar anomaly and the cerebral ischaemic or haemorrhagic pathologies are discussed also from a review of the pertinent literature.  相似文献   
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Recurrent bacterial meningitis (RBM) in many instances is associated with identifiable anatomical defects. Presence of congenital deafness with recurrent meningitis should alert clinician for presence of middle and inner ear malformation. These defects can be demonstrated by various neuro imaging techniques and can be surgically corrected. In this case report we describe a child seen at our institute with congenital deafness and recurrent meningitis, discuss the approach to RBM and briefly describe inner ear malformation associated with the same and how to differentiate them.  相似文献   
94.
We report imaging and surgical findings of a symptomatic 40‐year‐old male with an anomalous left vertebral artery. MR, CT myelography, angiography, and intraoperative photos demonstrate the vertebral artery entering the thecal sac at the C1‐C2 intervertebral foramen and compressing the dorsal C2 nerve rootlets against the cord. Open microvascular decompression alleviated the patient's long‐standing suboccipital and posterior cervical neck pain. An embryologic review of the vertebral and lateral spinal artery systems reveals possible developmental explanations for this variant. Intradural course of the vertebral artery at C2 is one of the few symptomatic developmental vertebral artery anomalies. Recognition of this condition is important because surgical intervention can alleviate associated neck pain.  相似文献   
95.
Pigmented villonodular synovitis (PVNS) is a benign tissue proliferation characterized by its hyper‐vascularity within the lesion. The true etiology and cell source of this disease entity still remain unclear. Mesenchymal stem cells (MSCs) exist in various tissues of human body. However, it has not been clarified whether MSCs could be isolated from tissue of PVNS. Here, we isolated MSCs from PVNS (PVNS‐SCs), and by comparing to the MSCs from normal synovium (Syn‐SCs) of the same individual, we investigated whether PVNS‐SCs differed in the capacity for multi‐differentiation and inducing angiogenesis. We first demonstrated that PVNS‐SCs existed in the lesion of PVNS of three individuals. Moreover, we showed PVNS‐SCs had better osteogenic differentiation potential than Syn‐SCs, whereas Syn‐SCs had better capacity for adipogenic and chondrogenic differentiation. By genome–wide analysis of gene expression profile using a complementary DNA microarray and comparing to Syn‐SCs, we identified in PVNS‐SCs a distinct gene expression profile characterized by up‐regulation of genes involved in angiogenesis. In vitro and in vivo studies further confirmed that PVNS‐SCs had better capacities for promoting angiogenesis. In summary, the identification of PVNS‐SCs in PVNS tissue and their distinct angiogenic potential may help elucidate the underlying etiology of this disease. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:395–403, 2016.  相似文献   
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We propose a new method of organotypic roller 3D-culturing of the posterior sector of the eye. The method allows maintaining tissue viability in vitro for 14 days (which considerably surpasses the capacities of stationary culturing) and studying of the behavior of pigment retinal epithelial cells and choriocapillary membrane. Using this method we demonstrated phenotypic transformation, migration, and proliferation of pigment retinal epithelial cells under conditions of roller organotypic culture. In the absence of the retina, these cells exhibit properties of scavenger cells (phagocytes) both within and outside the layer. Under conditions of roller culturing in vitro, cells of the pigment retinal epithelium undergo changes similar to those observed in various retinal pathologies in vivo, including age-associated changes. Here we discuss the possibility of using the proposed method for evaluation of the effect of various factors added to the culture medium on the pigment epithelium, for modeling of processes developing in damaged pigment epithelium or under conditions of various pathologies, and for the study of regeneration responses in cells of pigment retinal epithelium in adult vertebrates. __________ Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 4, pp. 207–215, October, 2007  相似文献   
98.
Light exposure (6000 lux, 6 h) caused reactive changes in rat retinal pigmented epithelium and radial glia on day 1. Foci of lesions with virtually complete absence of the layers formed by neurosensory cells appeared on day 7. The number of destructively changed radial gliocytes in these foci was by one order of magnitude higher than in the control. Carovertin reduced destruction of pigmented epithelium and radial glia and reduced the area of lesion foci. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 144, No. 7, pp. 112–114, July, 2007  相似文献   
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