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21.
We conducted a study to determine if the risk of airway compromise following tonsillectomy with uvulopalatopharyngoplasty justifies the added cost and inconvenience of step-down monitoring in an intensive care unit. We performed a retrospective chart review of 130 patients with obstructive sleep apnea who had undergone isolated tonsillectomy with uvulopalatopharyngoplasty at our tertiary care center. The average length of stay in the step-down unit was 18 hours. We found that only eight of these patients (6.2%) had a postoperative desaturation level of less than 90%, including three of 12 patients (25%) who had comorbid conditions. No patient had an adverse respiratory event. We conclude that step-down monitoring in an intensive care unit is not necessary, although caution should be exercised in monitoring patients with comorbidities because they appear to be more prone to desaturation. A complete lack of adverse respiratory events has not been reported in previous studies.  相似文献   
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We describe a case of positional dyspnea due to compression of the tracheobronchial tree by an extensive thoracic aneurysm. In a 77-year-old woman with long-standing systemic hypertension, intermittent anterior chest pain gradually developed over several years. She had no history of asthma or thoracic trauma. She was admitted to our hospital because of sudden, severe shortness of breath. The breathlessness was markedly worse when she lay on her back or on her right side. On physical examination, she was in acute respiratory distress with cyanosis, severe hypertension (180/110 mmHg), tachycardia, and inspiratory stridor. A chest X-ray film showed loss of volume and nearly complete radiopacity of the left hemithorax. Arterial blood gas analysis revealed an arterial oxygen partial pressure of 54.8 mmHg, a carbon dioxide partial pressure of 39.8 mmHg, and an oxygen saturation of 84.5 percent on room air. Computed tomographic examination of the thorax showed dilation of the aortic arch and descending aorta, and marked compression of the trachea and the left main bronchus. Examination with a fiberoptic bronchoscope revealed extrinsic compression of the trachea just proximal to the carina. The patient's symptoms stabilized. However, she did not undergo surgery because of her age and because of the size of the aneurysm. She died due to rupture of the aneurysm.  相似文献   
24.
Urinary protein and calcium excretion were assessed in 77 patients with the hepatic glycogen storage diseases (GSD): 30 with GSD-I (median age 12.4 years, range 3.2-32.9 years), 25 with GSD-III (median age 10.5 years, range 4.2-31.3 years) and 22 with GSD-IX (median age 11.8 years, range 1.2-35.4 years). Inulin (Cinulin) and para-aminohippuric acid (CPAH) clearances were also measured in 33 of these patients. Those with GSD-I had significantly greater albumin (F = 15.07, P < 0.001), retinol-binding protein (RBP) (F = 14.66, P < 0.001), N-acetyl-beta-D-glucosaminidase (NAG) (F = 9.41, P < 0.001) and calcium (F = 7.41, P = 0.001) excretion than those with GSD-III and GSD-IX. GSD-I patients (n = 18) also had significantly higher Cinulin (F = 5.57, P = 0.009), but CPAH did not differ (F = 0.77, NS). Renal function was normal in GSD-III and GSD-IX patients. In GSD-I, Cinulin (r = -0.51, P = 0.03) and NAG excretion (r = -0.40, P = 0.03) were inversely correlated with age, whereas albumin excretion was positively correlated with age (r = +0.41, P = 0.03). RBP and calcium excretion were generally high throughout all age groups. Hyperfiltration in GSD-I is associated with renal tubular proteinuria that occurs before the onset of significant albuminuria. Deficiency of glucose-6-phosphatase within the proximal renal tubule may primarily cause tubular dysfunction, glomerular hyperfiltration being a secondary phenomenon.  相似文献   
25.
Osteotomy has been used in treatment of unstable intertrochanteric hip fractures in an attempt to increase the stability of the fracture fragments. We have assessed this stability in a randomised prospective study on 138 patients, all having been fixed by dynamic hip screen, comparing anatomical reduction with medialisation osteotomy. The groups were similar in terms of age, gender and fracture configuration. There was no difference in final results in both groups except that operation time was longer in osteotomy group and the blood loss was more. We found no clear benefit from osteotomy and therefore recommend anatomical reduction and fixation by a sliding hip screw in most cases. Rarely, a fracture configuration which does not allow anatomical reduction may benefit from an osteotomy.  相似文献   
26.
Surface structure of thin silver films (200 Å) on two technologically important films, indium tin oxide (ITO) and aluminium oxide, has been studied using scanning tunneling microscope. ITO films were prepared by reactive electron beam evaporation. Aluminium oxide films were prepared by oxidizing 2000 Å thick aluminium films evaporated on to H2 terminated single crystal silicon substrates. The surface structure of silver on ITO and aluminium oxide appeared to be same and was characteristic of Stranski-Krastanov type. The observed asymmetry in the island shape was attributed to the anisotropic nature of the strain fields surrounding the nucleation centres.  相似文献   
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28.
The effects of receiver misplacement and the trough pointing towards the sun on the concentration characteristics of a composite parabolic trough are discussed. Results from some numerical calculations are presented graphically and discussed.  相似文献   
29.
解放前我国学者对新疆石油地质的调查和研究   总被引:1,自引:0,他引:1  
20世纪初,随着近代地质学在中国的形成和发展,一些学者开始了对新疆石油地质的调查和研究,30年代末以前,翁文灏,章鸿钊等学者利用文献和间接获得的资料,对新疆石油资源进行了宏观考察和若干重要油苗的地质研究;40年代开始,黄汲清等地质家在新疆进行实地考察,对独山子油田进行了详细研究,并在南北疆部分地区进行了路线性石油地质调查。  相似文献   
30.
A method for high-performance, software testing, called mutant unification, is described. The method is designed to support program mutation on parallel machines based on the single instruction multiple data stream (SIMD) paradigm. Several parameters that affect the performance of unification have been identified and their effect on the time to completion of a mutation test cycle and speedup has been studied. Program mutation analysis provides an effective means for determining the reliability of large software systems and a systematic method for measuring the adequacy of test data. However, it is likely that testing large software systems using mutation is computation bound and prohibitive on traditional sequential machines. Current, implementations of mutation tools are unacceptably slow and are only suitable for testing relatively small programs. The proposed unification method provides a practical alternative to the current approaches. The method also opens up a new application domain for SIMD machines  相似文献   
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