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Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.  相似文献   
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Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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Development of a reconstructed human skin model for angiogenesis   总被引:4,自引:0,他引:4  
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells.  相似文献   
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A case of an isolated, displaced fracture of the capitate is described. This rare carpal injury was treated by internal fixation with two Herbert screws. The fracture united and the patient achieved an excellent range of wrist motion. The Herbert screw is useful in the treatment of displaced fractures of the capitate since the screw maintains reduction, compresses the fracture site, and allows early wrist motion.  相似文献   
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Thoracic paravertebral space location   总被引:2,自引:0,他引:2  
J. RICHARDSON  MD  MRCP  FRCA    S. P. S. CHEEMA  FRCA    J. HAWKINS FRCA    S. SABANATHAN MD  FRCS   《Anaesthesia》1996,51(2):137-139
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The progress of cognitive visual dysfunction over an 8-year period of a child who sustained bilateral occipital-lobe infarctions at the age of 21/2 years is described. She survived with normal intelligence and went on to attend mainstream school. She manifested many features of cognitive visual impairment and, in particular, developed a form of pure alexia without agraphia. She achieved some letter-by-letter reading but no sight vocabulary development, including to her own name. She learned to write imaginatively employing phonetically true spelling but cannot read what she has written. Her progress and the difficulties encountered during the management of her condition are discussed in this first case report of the evolution of pure alexia without agraphia in childhood. The features of this syndrome in the developing child who has never developed the capacity to read are contrasted with that seen in affected adults.  相似文献   
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