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51.
Cultured bovine corneal endothelial cells were labeled with either [35S]sulfate or a combination of [3H]glucosamine and [35S]methionine. The medium proteoheparan sulfate (HS-PG) and cell-associated HS-PG were isolated and identified as heparan sulfate-containing proteoglycans by the susceptibility of their glycosaminoglycan component to specific enzymatic and chemical degradation. The native medium HS-PG has an apparent Mr of about 300,000 and an Mr of its protein core of 64,000, while the native cell-associated HS-PG had a lower molecular weight (approx. 100,000) and an Mr of its protein core of 33,000. The protein core of both HS-PG types consisted of a single polypeptide chain. After beta-elimination reaction of the native HS-PGs the resulting heparan sulfate side chains of medium HS-PG had an Mr of about 60,000, and those of cell-associated HS-PG an Mr of about 30,000. The different molecular parameters of medium HS-PG and cell-associated HS-PG refer to different functional roles. The medium HS-PG secreted by the endothelial cells is regarded as a metabolic precursor of the Descemet's membrane, while the cell-associated HS-PG might represent a cell membrane-integrated proteoglycan.  相似文献   
52.
Iatrogenic damage to the orbital fascial system during strabismus surgery may lead to adherences with resulting problems of motility. To prevent new adherences in revisional surgery, several materials were tried, with varying degrees of success. The authors tested Polyglactin 910, popular as a suture material in strabismus surgery, in the form of a net. The material is hydrolytically soluble. Since the tissue response is finished before dissolution of the implant, it seemed that Polyglactin would be a suitable barrier to the formation of adhesions in Tenon's capsule. The implant was applied in 11 patients, some of whom had already undergone several strabismus operations and had adhesions at the surgical site. In one case the implant was used in a primary procedure. In one patient revisional surgery was needed four weeks after surgery because of overeffect, and this provided an opportunity to investigate the implanted area histologically.  相似文献   
53.
A 16-year-old boy and a 17-year-old girl underwent successful closure of the meningomyelocele defect in childhood but they continued to suffer incontinence of stool and urine. After a 5-day trial with percutaneous electrostimulation of the pudendal nerve both patients received permanent neuroprosthetic implants. They became completely continent of stool and exhibited greater than 90% improvement in urinary control. These patients demonstrate that there is a small subset of meningomyelocele patients who, despite absence of spontaneous reflex tonus in the urinary and bowel sphincters, nevertheless have preserved motor capabilities.  相似文献   
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Cardiac catheterisations in newborns and infants are being performed routinely in increasing numbers for diagnostic and therapeutic purposes. Rarely, the femoral artery or the iliac artery will be completely occluded after such a procedure, and growth retardation of the lower extremity can result. We report on a case of iliofemoral artery occlusion following cardiac catheterisation in an infant. Twelve years later, a difference of 5.5 cm in leg length was noted, as well as a difference in shoe size and intermittent claudication. Following operative reconstruction, the child’s leg pain ceased. Two years after surgery, differences in leg lengths and shoe sizes are no longer significant. Vascular complications should not be underestimated despite the juvenile potential for collateral vessels. Even in the absence of signs of ischaemia, these complications necessitate further investigation and adequate treatment in due course.  相似文献   
60.
Forty women, aged 26-40 years, were investigated with regard to gastric contents and pH before general anaesthesia. The patients were divided into two groups (20 in each). Group 100 received 0.3 mg kg-1 diazepam orally with 100 ml of water 2 h before surgery. Group 50 received 0.3 mg kg-1 diazepam with 50 ml of water 2 h before surgery. The amount of gastric content was significantly greater in Group 100 than in Group 50 (P less than 0.05). There was no statistical difference in pH values between the groups. The number of patients with both gastric pH less than 2.5 and gastric volume greater than 25 ml was significantly higher in Group 100 compared to Group 50 (P less than 0.05). We cannot recommend the use of oral premedication using these amounts of water, considering the increased risk of aspiration of gastric contents.  相似文献   
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