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61.
Sharing techniques using the upper eyelid to reconstruct the lower one have been criticised for causing distortion of the normal upper lid leading to corneal exposure and possible visual disturbance, and for creating second-rate lids. A modification of previously described tarsoconjunctival flap techniques is described which minimises the known complications of earlier methods. A flap of conjunctiva alone is mobilised from the upper eyelid and covered with a full thickness skin graft. A second minor procedure to divide the flap from its donor site is necessary 2 weeks later. Forty-three patients over a 25-year period have undergone total lower eyelid reconstruction with this modified technique and are reviewed with some illustrative cases. Total or subtotal lower eyelid reconstruction is most commonly performed following tumour resection and only occasionally to correct congenital or traumatic defects. The surgical techniques available still cause controversy (Byrd, 1983). An upper lid sharing technique has been criticised for possibly causing a shortened or distorted normal lid (Mustardé, 1981). A modification of this method is described which has been used for over 25 years and has reduced the morbidity of the procedure, leading to acceptable cosmetic and functional long-term results.  相似文献   
62.
The suction trephine was studied in 31 aphakic and pseudophakic penetrating keratoplasty patients (31 eyes). The postoperative corneal astigmatism averaged 3.9 +/- 2.8 diopters overall. The 15 pseudophakic cases in nonscarred corneas showed a marked reduction in postoperative corneal astigmatism (3.59 diopters) when compared to previous reports. Our results have encouraged us to continue use of the suction trephine in all aphakic or combined keratoplasty procedures.  相似文献   
63.
BACKGROUND: Recent case reports, small series, and uncontrolled, unblinded studies have suggested that tranylcypromine may produce pressor reactions in some patients. However, the physiologic mechanism underlying this cardiovascular change is unknown. METHOD: The authors studied the acute cardiovascular effects of tranylcypromine in 13 patients and attempted to correlate these changes with plasma measures of parent drug, possible pressor metabolites, norepinephrine, and 3-methoxy-4-hydroxyphenylglycol. RESULTS: Significant elevations in supine blood pressure occurred after administration of tranylcypromine and correlated with tranylcypromine dose. Similar changes were not observed in standing blood pressure measurements. In fact, an orthostatic decrease in blood pressure and increase in heart rate were observed. Amphetamine-like metabolites were not found. CONCLUSIONS: The authors speculate on possible mechanisms underlying these opposite cardiovascular effects.  相似文献   
64.
Single lung transplantation (SLT) has been considered physiologically inappropriate for patients with chronic obstructive pulmonary disease (COPD). It has been postulated that the high static compliance and elevated pulmonary vascular resistance of the native lung functioning in parallel with the more normal allografted lung could cause unacceptable ventilation-perfusion mismatching and/or overinflation of the native lung with encroachment on the expansion of the transplanted lung. While some degree of ventilation-perfusion imbalance may be physiologically obligatory after SLT for COPD, a significant disruption in gas exchange may not occur unless a complication, such as rejection or infection, arises in the transplanted lung. A 60-year-old man with COPD who underwent successful SLT is presented and discussed. In spite of scintigraphic evidence of ventilation-perfusion mismatching between the native lung and the allograft during the first six postoperative weeks, the recipient had normal resting gas exchange on room air after the second postoperative week. Fourteen weeks after transplantation, his maximum oxygen uptake was 37.3 percent of the predicted maximal value, and no evidence of ventilatory limitation was detected. His functional status and lifestyle have been markedly improved by SLT. The role of SLT for COPD should be reconsidered. It may be a reasonable transplantation alternative for selected patients with COPD who are not candidates for double lung transplantation (DLT).  相似文献   
65.
Herpes simplex encephalitis may be underdiagnosed in Britain. We report eight patients treated at one hospital over three years. Fever, impaired consciousness or focal neurological signs were seen in all patients at presentation but herpes simplex encephalitis was rarely considered as the initial diagnosis. The electroencephalogram was the only initial investigation that was abnormal in each case and was the most useful test in establishing a clinical diagnosis. The diagnosis was confirmed by laboratory methods in each case. Following acyclovir treatment five patients were able to resume normal activities, one patient has moderate disability and two patients died. Three patients showed clinical evidence of relapse but two improved after further treatment with acyclovir. Herpes simplex encephalitis is a treatable condition and should be considered in all patients presenting with fever and neurological signs. The electroencephalogram is usually abnormal and the changes may be characteristic of the condition.  相似文献   
66.
A newborn infant presented with cardiac failure secondary to a peripheral cavernous haemangioma. She was successfully treated surgically but was later diagnosed as having GM1 gangliosidosis.  相似文献   
67.
The patient referral process is based on a complex set of social rewards and costs for the referring physician. For the physician or institution potentially receiving referrals, a key question is, why is one institution selected over other available choices? Factor analysis of a survey of rural physicians revealed five factors of reward and cost associated with the choice of where to refer patients. Further analysis of these factors suggested that the ability to have patients admitted and treated when necessary is central to the satisfaction of the referring physician and their willingness to continue the consultant relationship. Adequate information about the consultants was also important to satisfaction. Other factors have less influence. Further, “admissions when necessary” was the only reward/cost factor which predicted physicians who referred more to the university hospital than to other hospitals. If a university hospital wants to develop strategies to encourage referrals from rural physicians, it must be cognizant of these social reward-cost factors.  相似文献   
68.
Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.  相似文献   
69.
S J Kussick  J A Cooper 《Oncogene》1992,7(12):2461-2470
Little is known about the regulation of non-receptor tyrosine kinases in invertebrates. We have studied the relationship between the phosphorylation state of the Drosophila src 64B (Dsrc) gene product, p62D, and its tyrosine kinase activity in Drosophila Schneider 2 cells, using wild-type and mutated Dsrc constructs that were overexpressed by transient transfection. Phosphopeptide mapping showed that the putative regulatory C-terminal tyrosine (Tyr-547) of p62D was phosphorylated in vivo. In contrast to vertebrate src family kinases overexpressed in fibroblasts, wild-type p62D overexpressed in Schneider 2 cells was phosphorylated at additional tyrosines outside of the C-terminus. These tyrosines corresponded to the major in vitro autophosphorylation sites. Overexpression of wild-type p62D or several catalytically active p62D mutants significantly increased the phosphorylation of numerous Schneider cell proteins on tyrosine, while expression of catalytically inactive mutants of p62D had no such effect. Thus, in contrast to the repression of src family kinase activity in fibroblasts, p62D is catalytically active when overexpressed in Drosophila cells, perhaps because of substoichiometric C-terminal tyrosine phosphorylation. These results raise the possibility that fly development will be sensitive to ectopic expression of p62D.  相似文献   
70.
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