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Thirty cigarette smokers and 25 non-smoking controls, all men were evaluated by history, physical examination and simple spirometry. The history and physical examination were not of much use in predicting airflow obstruction. Forced mid-expiratory flow (FEF 25-75%) was abnormally low in 23 of the 30 subjects, while forced expiratory volume in 1 second (FEV1) and FEV1/FVC (forced vital capacity) were less sensitive. Thus simple spirometry is a useful screening tool to detect early airflow obstruction even when it is clinically undetectable.  相似文献   
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Three-dimensional (3D) reconstruction in routine computerized tomography (CT) presupposes that the referring clinicians are motivated, software programs are of good quality, a second working console is available and manipulations are made by experienced persons. Maxillofacial surgery is the main, conventional indication, but the method is also used to plan the surgical treatment of craniofacial malformations and that of injuries and tumours. 3D reconstruction cannot replace a thorough analysis of the acquisition sections since its spatial definition is not as good as theirs. Without competing with pure research-work, a number of applications remain in the realm of speculative imaging, but it cannot be denied that 3D reconstruction has an interesting potential for teaching.  相似文献   
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Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

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Background:   

Cases of extrahepatic biliary tree trauma are not as common as other intraabdominal injuries and may pose a diagnostic and therapeutic challenge.  相似文献   
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BACKGROUND CONTEXT: Diastematomyelia is uncommon and rarely presents in adulthood. This report draws attention to the fact that patients who underwent spinal fusion for deformity before the widespread use of computed tomography (CT) and magnetic resonance imaging (MRI) may have unrecognized spinal cord abnormalities. This should be considered if revision surgery is contemplated. PURPOSE: This case report focuses on the late presentation of lower-extremity weakness in a 44-year-old woman with a split cord malformation (diplomyelia), diastematomyelia and tethered cord syndrome. STUDY DESIGN/SETTING: METHODS: The patient underwent instrumented posterior spinal fusion with a Harrington rod as a child for progressive thoracolumbar scoliosis. As an adult, she developed paraparesis after a traumatic event.The patient underwent decompressive laminectomy, subtotal resection of the old fusion mass and resection of the osseous septum. Postoperatively, an anterior spinal fluid leak in the lower thoracic region required repeated fascial grafting, resection of a pseudomeningocele and reverse left latissimus dorsi flap transfer. The leak was controlled, and the patient had near complete resolution of her paraparesis 1 year after her surgery. RESULTS: The case described herein is unusual in that patients with diplomyelia and diastematomyelia rarely are symptomatic in adulthood. However, trauma may precipitate the onset of neurologic symptoms. This patient underwent spinal surgeries to address deformity, pain and progressive lower-extremity weakness. Preoperative CT and MRI studies showed a split cord malformation and diastematomyelia at L1-L2 with spinal stenosis and tethering of both hemicords. CONCLUSIONS: Progressive weakness without any previous neurologic deficit or neurocutaneous stigmas of an underlying spinal cord abnormality may develop in the adult with unrecognized diastemotomyelia. This case demonstrates that a thorough preoperative workup of patients with complex spinal deformities is imperative.  相似文献   
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