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791.
792.
The electroretinograms (ERGs) from 14 patients with proliferative diabetic retinopathy were recorded before and after peripheral retinal ablation by photocoagulation. It was expected that the ERG would be reduced in amplitude in proportion to the area of retina destroyed by the treatment. The ablation treatment, carried out in a standard manner in each patient, resulted in a decrease of ERG amplitude that varied from 10 to 95% among the patients, and caused an increase in ERG latency and implicit time in several patients. This suggests a wide variability in the area of retina affected by the treatment, and the possibility of an effect of the procedure on adjacent untreated retina in some diabetic patients.  相似文献   
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795.
The rapid development of suppurative reaction in response to a copper-containing intraocular foreign body disposes the eye to a poor prognosis. An intraocular brass foreign body case involving cornea, iris, lens, vitreous and retina was satisfactorily managed by early foreign body removal and corneal transplantation followed by scleral buckling for retinal detachment. Early intervention is advocated as alternative management with expectation of improvement in the prognosis for recovery of useful visual function.  相似文献   
796.
There is a considerable controversy regarding the frequency and significance of vascular lesions in leprosy. Twenty-six cases of leprosy below the age of 40 years, without any local or systemic arterial disease and normal looking hands were subjected to brachial arteriography. One patient had posterior tibial arteriography also. The diagnosis of leprosy was confirmed by histology or bacteriological staining techniques. Biopsy material was studied from the involved areas and similar material was obtained from nine matched control subjects at autopsy. Skin thermometry and reflex vasodilatation was studied in eight cases. Arteriographic abnormalities such as occlusion, narrowing, tortuosity, dilatation, irregularity and incomplete filling were seen in more than two vessels in the hand in 50%, and in the digits in 75% of the cases. The ulnar artery was more frequently involved than the radial. Superficial and deep palmar arches were equally affected. Marked increase in arcuate vessels was noticed in nearly three-quarters of the patients, and in some, arcuate vessles were serving as collaterals. Histologically all sizes of vessles, including the capillaries, showed changes in nearly half the cases. Reflex vasodilation was lost in three cases of dimorphous leprosy and impaired or absent in three out of five cases of lepromatous leprosy. There was no predilection for any form of leprosy to show arterial changes more than the other. This study clearly demonstrates that the arterial involvement in leprosy is very frequent and must be playing an important role in causing mutilation and deformities of hands and feet.  相似文献   
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798.
OBJECTIVE: We describe CT findings after laparoscopic repair of ventral hernia with emphasis on formation of postoperative fluid collections that can mimic recurrent bowel herniation or infected postoperative fluid collections. CONCLUSION: The porous property of the mesh used in laparoscopic repair of ventral hernia allows reaccumulation of fluid in the existing hernia sac or spaces in the subcutaneous tissues that can be created by laparoscopic manipulation. These fluid collections should be expected and are differentiated from infected fluid collections or hernia recurrence by clinical presentation, laboratory data, and lack of ancillary features associated with true hernia such as presence of hernia sac, herniated mesentery, or bowel obstruction.  相似文献   
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