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OBJECT: Delayed cerebral ischemia is a major cause of morbidity and death following aneurysmal subarachnoid hemorrhage and requires timely intervention for a successful outcome to be achieved. In this study the investigators compared the commonly used Fisher scale with 2 newer radiographic scales for the prediction of vasospasm, delayed infarction, and poor outcome. METHODS: This was a single-center, retrospective cohort study involving 271 consecutive patients with a ruptured cerebral aneurysm. Without knowledge of subsequent events, admission CT scans were each assigned scores by using 3 different grading schemes: the Fisher, modified Fisher, and Claassen scales. For each of the scales, the relationship between an increasing score and the risk of later complications was assessed in univariate and multiple logistic regression analyses. RESULTS: With the Fisher scale, the risk of complications was relatively high when the score was 3, but not for other scores. In contrast, using the other scales, there was a more linear relationship between a rising score and the frequency of complications. This was particularly true for the modified Fisher scale, in which each stepwise increase was associated with an escalating risk of vasospasm, delayed infarction, and poor prognosis. Kappa scores measuring interobserver variability among 4 CT readers were also slightly better with the newer scales. CONCLUSIONS: Although the modified Fisher and Claassen scales have yet to be prospectively validated, the authors' findings suggest that the clinical performance of these systems is superior to that of the Fisher scale.  相似文献   
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Davidson  HD; Abraham  R; Steiner  RE 《Radiology》1985,155(2):371-373
Three patients who had complete agenesis and two patients who had partial agenesis of the corpus callosum (ACC) underwent magnetic resonance (MR) imaging. In addition to excellent visualization of the indirect signs of ACC, direct vivid display (short T1) of the corpus callosum on sagittal images allowed better evaluation of subtle abnormalities than has been possible with other modalities. Associated abnormalities were also well-displayed. MR is the initial procedure of choice in evaluation of the corpus callosum.  相似文献   
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1临床资料患儿,女性,4岁。因间断性腹痛1月加重伴黑便15d,呕吐2d入院。患儿病前无明确外伤史,其母于入院前15d发现左膝部有损伤痕,已愈合,行腹部B超检查,提示肝胆肾正常,胰大小正常,边界清,实质回声均匀,主胰管不扩张,肝前区肝肾夹角及脾肾夹角可见53mm的液性暗区,内见肠管蠕动  相似文献   
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Background: The aim of the present study was to determine the mechanisms underlying Type 2 diabetes remission after gastric bypass (GBP) surgery by characterizing the short‐ and long‐term changes in hormonal determinants of blood glucose. Methods: Eleven morbidly obese women with diabetes were studied before and 1, 6, and 12 months after GBP; eight non‐diabetic morbidly obese women were used as controls. The incretin effect was measured as the difference in insulin levels in response to oral glucose and to an isoglycemic intravenous challenge. Outcome measures were glucose, insulin, C‐peptide, proinsulin, amylin, glucagon, glucose‐dependent insulinotropic polypeptide (GIP), glucagon‐like peptide‐1 (GLP‐1) levels and the incretin effect on insulin secretion. Results: The decrease in fasting glucose (r = 0.724) and insulin (r = 0.576) was associated with weight loss up to 12 months after GBP. In contrast, the blunted incretin effect (calculated at 22%) that improved at 1 month remained unchanged with further weight loss at 6 (52%) and 12 (52%) months. The blunted incretin (GLP‐1 and GIP) levels, early phase insulin secretion, and other parameters of β‐cell function (amylin, proinsulin/insulin) followed the same pattern, with rapid improvement at 1 month that remained unchanged at 1 year. Conclusions: The data suggest that weight loss and incretins may contribute independently to improved glucose levels in the first year after GBP surgery.  相似文献   
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Endoscopic ultrasound (EUS) is one of the most challenging endoscopic procedures to learn and requires integration of both cognitive and endoscopic skills. EUS also is an important technology with a growing number of therapeutic applications. Despite its increasing role in managing gastrointestinal diseases, EUS technology remains largely limited to the confines in academic medical centers and tertiary referral centers because of issues concerning cost, equipment availability, efficiency of implementation, reimbursement, and most importantly, training. This article reviews the factors that are considered important for EUS training and discusses the use of various simulators and the potential role of these simulators in the future.  相似文献   
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BACKGROUND: In the presence of a compatible clinical picture, the diagnosis of sarcoidosis requires pathologic confirmation of noncaseating epithelioid granuloma in affected tissues. The standard procedure of choice for most patients is a bronchoscopy with transbronchial biopsy (TBB), which has a diagnostic yield of 40% to 90%. The lowest yield with TBB is in cases that present with predominant mediastinal or intra-abdominal lymphadenopathy (LN) and minimal parenchymal lung involvement. OBJECTIVE: To study the diagnostic yield of EUS-guided FNA in diagnosing sarcoidosis with predominant LN or masses. DESIGN: Retrospective chart review. SETTING: Teaching university hospital. PATIENTS: Analysis of 21 consecutive patients with sarcoidosis and predominant mediastinal and/or intra-abdominal LN or masses who underwent EUS-guided FNA. RESULTS: EUS-guided FNA diagnosed sarcoidosis in 18 of 21 patients (86%). In 3 patients, EUS-guided FNA was either not diagnostic or inconclusive, and patients underwent mediastinoscopy with lymphadenectomy, which established the diagnosis of sarcoidosis. Seven of the 21 patients (33%) had intra-abdominal LN and/or masses, and EUS-guided FNA of the intra-abdominal pathology was diagnostic of sarcoidosis in 4 of the 7 patients (57%). Four of the 21 patients (19%) had a history of malignancy, and use of EUS-guided FNA helped in ruling out the recurrence of malignancy in 3 of the 4 patients (75%). LIMITATIONS: Mycobacterial and fungal culture was not obtained in all patients. CONCLUSIONS: EUS-guided FNA offers a practical, minimally invasive technique for the diagnosis of sarcoidosis in patients who present with predominant mediastinal and/or intra-abdominal LN or masses.  相似文献   
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