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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
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The purposes of this study were (1) to document the histopathological consequences of moderate traumatic brain injury (TBI) in anesthetized Sprague-Dawley rats, and (2) to determine whether posttraumatic brain hypothermia (30°C) would protect histopathologically. Twenty-four hours prior to TBI, the fluid percussion interface was positioned over the right cerebral cortex. On the 2nd day, fasted rats were anesthetized with 70% nitrous oxide, 1% halothane, and 30% oxygen. Under controlled physiological conditions and normothermic brain temperature (37.5°C), rats were injured with a fluid percussion pulse ranging from 1.7 to 2.2 atmospheres. In one group, brain temperature was maintained at normothermic levels for 3 h after injury. In a second group, brain temperature was reduced to 30°C at 5 min post-trauma and maintained for 3 h. Three days after TBI, brains were perfusion-fixed for routine histopathological analysis. In the normothermic group, damage at the site of impact was seen in only one of nine rats. In contrast, all normothermic animals displayed necrotic neurons within ipsilateral cortical regions lateral and remote from the impact site. Intracerebral hemorrhagic contusions were present in all rats at the gray-white interface underlying the injured cortical areas. Selective neuronal necrosis was also present within the CA3 and CA4 hippocampal subsectors and thalamus. Post-traumatic brain hypothermia significantly reduced the overall sum of necrotic cortical neurons (519±122 vs 952±130, mean ±SE, P=0.03, Kruskal-Wallis test) as well as contusion volume (0.50±0.14 vs 2.14±0.71 mm3, P=0.004). These data document a consistent pattern of histopathological vulnerability following normothermic TBI and demonstrate hypothermic protection in the post-traumatic setting.Supported by USPHS Grants NS30291 and NS27127  相似文献   
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Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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Background: A radical forequarter amputation with partial chest wall resection (one to four ribs) has been reported for benign and malignant lesions involving the shoulder and chest wall region. Concerns about reconstruction and postoperative pulmonary function have previously limited more extensive chest wall resections. The current report describes the first case in which a complete unilateral anterior and posterior chest wall resection and pneumonectomy (hemithoracectomy) accompany a forequarter amputation. A novel reconstructive technique used the full circumference of the forearm tissue with an intact ulna as a free osseomyocutaneous flap. Methods: In this case, a 21-year-old patient presented with an extensive recurrent desmoid tumor that involved the shoulder, brachial plexus, subclavian vein, and chest wall from the lateral sternal border to the midportion of the scapula and down to the eighth rib. The operative technique involved removal of the entire right hemithorax from the midline sternum to the transverse process posteriorly, down to the ninth rib inferiorly. Due to the absence of a rigid hemithorax, the uninvolved ipsilateral lung was also removed. The forearm flap was prepared before final separation of the specimen and division of the subclavian vessels. Results: Postoperatively, the patient maintained excellent oxygenation without atelectasis or fever and was extubated on the 15th postoperative day. As expected after pneumonectomy, significant decreases from preoperative to immediate postoperative values were noted for the vital capacity (VC) (from 4.87 L to 1.29 L), forced 1-s expiratory volume (FEV1) (from 3.77 L to 1.02 L), and inspiratory capacity (IC) (3.33 1 to 0.99 1). Rehabilitation included a specially designed external prosthesis to provide cosmesis and prevent scoliosis. By the 15th postoperative week the patient had returned to normal social and physical activities, with a gradual improvement in all respiratory parameters: VC 1.52 L, FEV1 1.29 L, IC 1.04 L. There has been no evidence of tumor recurrence at 1 year. Conclusions: This report provides evidence that a complete hemithoracectomy, pneumonectomy, and forequarter amputation can be safely performed for selective tumors involving the shoulder region with extensive chest wall invasion. Reconstruction may be achieved with an extended forearm osseomyocutaneous free flap with an excellent functional outcome. Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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