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91.
92.
改良义眼座眶内植入术的临床观察   总被引:1,自引:0,他引:1  
观察改良义眼座植入的临床效果。方法 眼球摘除后,羟基磷灰石义眼座植入肌圆锥内,前半部分以双层自体巩膜覆盖,结膜囊内旋转带孔眼模,常规睑裂缝合。结果 随访2个月-3年,1例球工,经缝合修补后修复,所有病例均义眼活动良好,矫正外形满意。结论 改良义眼座眶内植入术并发症少,疗效满意,比传统术式有更多优点。  相似文献   
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Hepatitis C virus (HCV) infection is highly prevalent among chronic dialysis patients (10% to 40%) and is the most common cause of chronic liver disease. However, there are no studies estimating the risk for death among dialysis patients infected with HCV compared with those not infected. We conducted a prospective cohort study to estimate the risk for death among chronic dialysis patients infected with HCV compared with those not infected. In 1992, 200 patients (91%) who had been undergoing dialysis therapy for at least 6 months consented to be screened for HCV infection by enzyme immunoblot assay and polymerase chain reaction (PCR). Information about potential confounders and potential risk factors for death and HCV infection was obtained from the dialysis center database. Patient outcomes collected included death, transplantation, and loss to follow-up. The Cox proportional hazards model was used to estimate the odds of death among dialysis patients who were positive for the HCV antibody and HCV RNA compared with negative patients. Forty-four patients (22%) were HCV antibody positive. Thirty-four patients (17%) were HCV RNA positive. Patients in the HCV RNA-positive group were more likely to be younger (51.8+/-12.6 v 57.2+/-17.3 years of age), men (77% v 54%), and black (65% v 37%). None of the home hemodialysis or peritoneal dialysis patients were HCV RNA positive, whereas one of the home hemodialysis and one of the peritoneal dialysis patients were HCV antibody positive. Two patients became infected with HCV during the follow-up period. Patients who were HCV RNA positive and those who were HCV antibody positive were at increased risk for death compared with patients who were negative (adjusted relative risk [aRR]=1.78; 95% confidence interval [CI], 1.01 to 3.14; P=0.045; and aRR=1.97; 95% CI, 1.16 to 3.33; P=0.012, respectively), after adjusting for time on dialysis, race, transplantation, and age. We conclude that HCV infection increased the risk for death during the study period compared with those not infected. Further studies should assess the measures used to prevent and treat HCV infection.  相似文献   
95.
BACKGROUND: Intravenously administered perfluorocarbon (PFC) emulsions increase oxygen solubility in plasma. PFC might therefore temporarily replace red cells (RBCs) lost during intraoperative hemorrhage. In patients who have undergone hemodilution, the return of autologous blood may be delayed by the administration of PFC, and autologous RBCs may be saved for transfusion after surgical bleeding is stopped and PFC is cleared by the reticuloendothelial system. STUDY DESIGN AND METHODS: In 22 anesthetized, hemodiluted dogs (hemoglobin [Hb] 7 g/dL) breathing 100-percent O2, an intraoperative volume-compensated blood loss was simulated. The efficacy of three therapeutic regimens in maintaining tissue oxygenation was compared: 1) RBC group (n = 7): maintenance of a Hb > 7 g per dL by transfusion of autologous RBCs; 2) PFC group (n = 7): bolus application of a second-generation PFC emulsion (60% wt/vol perflubron) and further acute normovolemic hemodilution (ANH) to a Hb of 3 g per dL; and 3) control group (n = 7): further ANH alone to a Hb of 3 g per dL. Systemic and myocardial oxygenation status and tissue oxygenation were assessed. RESULTS: Autologous RBCs transfused to maintain a Hb of 7 g per dL preserved hemodynamics and tissue oxygenation during blood loss. In the PFC and control groups, heart rate and cardiac index increased significantly in response to further ANH. Tissue oxygenation was not different in the PFC and the RBC groups. Direct comparison of the PFC and control groups revealed better tissue oxygenation in the PFC group, as reflected by significantly higher mixed venous, coronary venous, and local tissue pO2 on liver and skeletal muscle. CONCLUSION: Bolus intravenous administration of 60- percent (wt/vol) perflubron emulsion and further hemodilution from a Hb of 7 g per dL to one of 3 g per dL were as effective as autologous RBC transfusion in maintaining tissue oxygenation during volume-compensated blood loss designed to mimic surgical bleeding.  相似文献   
96.
Damage occurs early in systemic vasculitis and is an index of outcome   总被引:2,自引:0,他引:2  
Because death after acute systemic vasculitis is now uncommon, alternative measures of outcome are required. A significant component of patient morbidity is disease-related damage, which can be quantified by the Vasculitis Damage Index (64 items in 11 organ-based systems). We investigated serially the time-course of damage in 120 patients with systemic vasculitis, to determine the earliest indicators of outcome. High damage scores at 2 years after presentation were characteristic of fatal disease (OR 8.1-12.4). Significant damage occurred within 6 months of presentation, and was a feature of fatal disease. More damage occurred after presentation than after relapse. Lung and multi-system damage were early indicators of poor outcome in severe non-fatal disease. Damage occurs early in systemic vasculitis, and is an indicator of poor outcome. This novel observation, together with evidence of persistent subclinical disease activity and the high frequency of relapse, suggests a need for new treatment strategies. Analogy with the management of acute leukaemia suggests a strategy of early diagnosis and intensive induction of remission, with early escalation of treatment for resistant disease.   相似文献   
97.
Machado-Joseph disease (MJD), one of the most prevalent autosomal dominant cerebellar ataxias, is a neurodegenerative disease that starts during adulthood, with patients showing difficulties in gait, later becoming bedridden, and ultimately presenting premature death. There is, however, scarce data quantifying disease impact on patient survival. We investigated the overall survival of a large series of MJD patients and compared it with the survival of their asymptomatic relatives. A total of 412 affected and 413 unaffected individuals were ascertained from a consecutive sample of 82 families with a molecular diagnosis of MJD. Estimated mean survival time was 63.96 years [95% confidence interval (CI), 62.09-65.83] for the affected group and 78.61 years (95% CI, 74.75-82.47) for the unaffected group (p < 0.001). For a subset of 366 patients, mean age at onset was 36.37 years (95% CI, 35.21-37.53) and survival after disease onset was estimated as 21.18 years. Early onset and large CAG length predicted shorter overall survival times. This study presents quantitative data on the impact of MJD on overall survival, a phenomenon that is related to CAG length, age at onset, and year of birth.  相似文献   
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99.
A 5-month-old white boy had a pinhead red spot on his left malleolar region since birth. His mother noted progressive growth and, when he was first examined, the lesion measured 30x25x20 mm in size, had a pyramidal shape, covered by erythematous and smooth skin, with teleangiectasia. The tumor was soft on paipation and movable over the deeper structures (Fig. 1a). X-ray examination revealed no bone abnormalities at that time.
Just before the programmed incisional biopsy, the patient had a febrile episode due to upper respiratory tract viral infection during which the tumor became ulcerated, bleeding and painful (Fig. 1b). As the bleeding was constant the lesion was surgically excised, at which time the whole gelatinous mass was easily detached from the aponeurotic structures (Fig. 1c). The tumor measured 36x31 x30 mm and had a whitish, smooth cut surface crossed by small blood vessels.
Histopathologic examination revealed a tumor mass extending from the mid dermis to the subcutaneous fat and composed of tightly packed fusiform cells in close opposition with lined vascular channels (Fig. 2a). There were atypical areas and mitotic figures were frequently seen. A reticulin preparation showed a dense network surrounding vessels and pericytes. The vessels branched in a staghorn configuration (Fig. 2b). The immunoperoxidase technique with monoclonal antibody anti-Factor VIII was positive in the endothelial cells surrounded by tumor cells (Fig. 2c).
Seven months after surgery the patient returned with a painful subcutaneous mass on the upper third of his left leg that was adherent to the tibial bone. X-ray examination disclosed osteolytic lesions at the tibial base and destruction of the peroneal head (Fig. 3).
The patient was submitted to radiotherapy, amputation of the left lower limb in the middle portion of the thigh and chemotherapy. He is clinically well 3 years after treatment.  相似文献   
100.
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