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The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus. 相似文献
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J. M. Gloor F. G. Cosio D. J. Rea H. M. Wadei J. L. Winters S. B. Moore S. R. DeGoey D. J. Lager J. P. Grande M. D. Stegall 《American journal of transplantation》2006,6(8):1841-1847
Recent protocols have allowed successful positive crossmatch (+XM) and ABO incompatible (ABOI) kidney transplantation, although their long-term outcome is not clear. To begin to assess this issue we compared protocol biopsies performed 12 months posttransplant in 37 +XM, 24 ABOI and 198 conventional allografts. Although the majority in all three groups had only minimal histologic changes, transplant glomerulopathy (TG) was significantly increased in +XM (22% vs. 13% ABOI vs. 8% conventional, p = 0.015), and correlated with prior humoral rejection (HR) by multivariate analysis (odds ratio 17.5, p < or = 0.0001). Patients with a prior history of HR also had a significant increase in interstitial fibrosis (No HR 54% vs. HR 86%, p = 0.045). In the absence of HR no difference in histologic changes was seen between groups, although all three groups had a demonstrable mild increase in interstitial fibrosis from biopsies performed at the time of transplant. Thus, although HR is associated with an increase in TG, in its absence allograft histology is similar in +XM, ABOI and conventional allografts 1 year posttransplant. 相似文献
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Janice Winters 《AAOHN journal》2002,50(6):271-274
1. The use of standardized nursing language is important to the advancement of nursing knowledge and practice. The standardization of nursing diagnoses, interventions, and outcomes provides a means for collecting and analyzing large clinical databases. 2. The occupational health nurse has a clear role in developing health and safety programs. Standardized language using North American Nursing Diagnosis Association diagnoses, nursing outcomes classification, and nursing intervention classification can be incorporated into these programs. 3. The use of standardized taxonomies in the primary prevention of cumulative trauma disorders demonstrates how these systems are integrated into the documentation of the nursing process in a nursing care plan. 相似文献
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Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
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A newborn term male infant was found to have the stigmata of VACTERL syndrome, including cervical and thoracic hemivertebra, partial sacral agenesis, 13 pairs of ribs, high imperforate anus with rectovesical fistula, and tracheoesophageal fistula with proximal esophageal atresia. No open spinal dysraphism or skin dimpling was seen. Ultrasonography of the spinal cord was performed to screen for occult anomalies. The examination revealed a lipoma of the filum terminalis and a low-lying conus medullaris at the L3-L4 level with a large central cystic structure in the terminal cord, which was continuous with the central canal (Fig. 1). This was thought to most likely represent a dilated ventriculus terminalis, and the diagnosis was confirmed on a subsequent MR image (Fig. 2). Fluid in the cyst followed cerebrospinal fluid signal in all sequences. We observed no abnormal signal in the adjacent parenchyma or enhancement associated with the cystic mass. A cranial ultrasonogram did not reveal any intracranial anomalies. The patient demonstrated no neurologic deficits in the lower extremities. Bowel and urinary continence was not assessable in this infant. 相似文献