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71.
Monocular deprivation has been associated with both specific deficits and enhancements in visual perception and processing. In this study, performance on a visuo-spatial memory task was compared in congenitally monocular individuals and sighted control individuals viewing monocularly (i.e., patched) and binocularly. The task required the individuals to view and memorize a series of target locations on two-dimensional matrices. Overall, congenitally monocular individuals performed worse than sighted individuals (with a specific deficit in simultaneously maintaining distinct spatial representations in memory), indicating that the lack of binocular visual experience affects the way visual information is represented in visuo-spatial memory. No difference was observed between the monocular and binocular viewing control groups, suggesting that early monocular deprivation affects the development of cortical mechanisms mediating visuo-spatial cognition.  相似文献   
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BACKGROUND: There is little information on the role of bisphosphonates and bone mineral density (BMD) measurements for the follow-up and management of bone loss and fractures in long-term kidney transplant recipients. METHODS: To address this question, we retrospectively studied 554 patients who had two BMD measurements after the first year posttransplant and compared outcomes in patients treated, or not with bisphosphonates between the two BMD assessments. Kaplan-Meier survival and stepwise Cox regression analyses were performed to examine fracture-free survival rates and the risk-factors associated with fractures. RESULTS: The average time (+/-SE) between transplant and the first BMD was 1.2+/-0.05 years. The time interval between the two BMD measurements was 2.5+/-0.05 years. There were 239 and 315 patients in the no-bisphosphonate and bisphosphonate groups, respectively. Treatment was associated with significant preservation of bone loss at the femoral neck (HR 1.56, 95% CI 1.21-2.06, P=0.0007). However, there was no association between bone loss at the femoral neck and fractures regardless of bisphosphonate therapy. Stepwise Cox regression analyses showed that type-1 diabetes, baseline femoral neck T-score, interleukin-2 receptor blockade, and proteinuria (HR 2.02, 0.69, 0.4, 1.23 respectively, P<0.01), but not bisphosphonates, were associated with the risk of fracture. CONCLUSIONS: Bisphosphonates may prevent bone loss in long-term kidney transplant recipients. However, these data suggest a limited role for the initiation of therapy after the first posttransplant year to prevent fractures.  相似文献   
77.
Epidermoid carcinoma, that is, squamous cell carcinoma of the skin, is the most common malignant tumor of the lips. It occurs especially in men. Its primary causes are sun exposure, smoking, and chronic irritation. Leukoplakia is the most frequent precancerous lesion. Epidermoid carcinoma may appear clinically as a scaly erosion or an ulceration. Standard treatment is surgical excision with reconstruction.  相似文献   
78.
Chest re-exploration for complications after lung surgery.   总被引:2,自引:0,他引:2  
BACKGROUND: Review of the most recent chest re-explorations for lung surgery complications may show methods by which risks can effectively be reduced. METHODS: The data on rethoracotomies following lung surgery over the past 14 years in our department were retrospectively reviewed. The indication, the type of operation, the outcome, and various factors influencing the postoperative mortality were analyzed. From 1983 to 1996, 1960 patients underwent primary thoracotomies for various lung diseases. Among these, 73 (3.7%) patients required re-exploration for various postoperative complications. RESULTS: Mean age was 56.8 years (15-80 years). There were 66 (90.4%) men and 7 (9.6%) women. The most common indication for rethoracotomy was hemorrhage in 38 (52%) patients. The source of bleeding was a mediastinal and/or bronchial blood vessel in 8 patients and an intercostal blood vessel in 6 patients. Six patients had to be reoperated because of hemorrhage from a major artery of the hilus. In 14 cases the postoperative hemothorax occurred without evident surgical origin. Further indications for rethoracotomy were bronchopleural fistula (BPF) in 13 (17.8%) patients, and persistent parenchymal leak in 8 (10.9%) patients. There were 8 additional causes distributed among the remaining 14 (19.3%) patients. The overall mortality rate was 17.8% (13/73), with the highest (38.4%) among BPF patients. CONCLUSIONS: Postoperative complications following lung surgery which require rethoracotomy are rare. The most common complication is postoperative bleeding. This is followed by bronchial stump insufficiency which is associated with the highest mortality and morbidity. Our experience shows that the need for re-exploration can hardly be reduced but the indication for re-exploration should be established as early as possible to avoid late complications.  相似文献   
79.
A 66-year-old male patient developed significant pleural effusion on the right side six years after coronary bypass grafting and mitral valve replacement. After pleurocentesis, hemo-pneumothorax developed and finally resulted in complete atelectasis of the right lung. Three weeks later, the patient was transferred to our department, and underwent a right lateral thoracotomy. The hematoma was removed and a complete decortication was performed. Four hours postoperatively the patient developed severe SIRS with beginning multiorgan failure. Even extremely high doses of norepinephrine could not raise the systemic vascular resistance. Single intravenous administration of methylene blue lead to significant and permanent improvement of the hemodynamic status.  相似文献   
80.
The lateral-occipital tactile-visual area (LOtv) is activated when objects are recognized by vision or touch. We report here that the LOtv is also activated in sighted and blind humans who recognize objects by extracting shape information from visual-to-auditory sensory substitution soundscapes. Recognizing objects by their typical sounds or learning to associate specific soundscapes with specific objects do not activate this region. This suggests that LOtv is driven by the presence of shape information.  相似文献   
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