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991.
Normal and abnormal temporomandibular joint: MR imaging with surface coil   总被引:5,自引:0,他引:5  
The normal temporomandibular joint (TMJ) was evaluated using magnetic resonance (MR) imaging with a surface coil in five subjects and compared with the abnormal joint in 37 patients (aged 14-59 years; total joints studied, 76). Multisection 3-mm-thick sagittal, coronal, and axial images were obtained with a 1.5-T MR system and 6.5-cm-diameter surface coil using both partial saturation and spin-echo sequences (TR = 1,000 msec, TE = 20 or 25 msec). A comparison with arthrography (n = 13 joints), computed tomography (CT) (n = 11), and surgical (n = 5) findings demonstrated that MR imaging with a surface coil provided an accurate depiction of both normal and abnormal TMJs. MR provided information about meniscal position, morphology, and histology that was not available with either arthrography or CT alone. The imaging potential of MR and its noninvasive characteristics warrant priority for further examination of MR as a useful modality in the diagnosis of TMJ pain and dysfunction.  相似文献   
992.
The effectiveness of a shaped filter in improving nodule and infiltrate detection was measured by observer performance testing. Seven observers read 152 test radiographs of the chest obtained from human volunteers. Half the test radiographs had target images. Observer performance in detecting nodule or infiltrate images was compared with the shaped-filter system and with a conventional chest imaging system. The results were analyzed using receiver operating characteristic (ROC) techniques and indicate that the filter technique was not significantly different from the conventional technique in infiltrate depiction. Observer performance in detecting nodules was slightly worse on images obtained with the shaped-filter system.  相似文献   
993.
Johnson  JF; Woisard  KK 《Radiology》1989,170(2):483-486
The ability to detect ileocolic intussusception on the supine cross-table lateral radiograph of the abdomen in infants was prospectively evaluated in 12 cases (including two recurrences) over a 2-year period. The intussusceptions (including one recurrence) were directly depicted on five radiographs as a homogeneous water-density mass producing a convex interface with bowel gas at the anterior part of the abdomen. In another four patients, the intussusception produced an inappropriate craniocaudal separation of gas-filled bowel loops in the upper part of the abdomen, caudal to the liver shadow. The intussusception was prospectively recognized on the supine cross-table lateral radiograph in nine of 12 cases.  相似文献   
994.
A 34% response was obtained in 202 evaluable patients in the terminal phase of chronic granulocytic leukemia using combinations of hydroxyurea, 6-mercaptopurine, and corticosteroids. Twelve percent of responses were complete and 22% partial. Overall median survival was 12 wk. A 30 wk median survival for responding patients was statistically superior to the 7-wk survival for nonresponders (p less than 0.001). Response was inversely correlated with toxicity. No responses were obtained in patients sustaining both severe infectious and bleeding complications. No benefit could be demonstrated from the addition of vincristine in induction and daunorubicin for consolidation. Although the response frequency and duration of survival with this combination chemotherapy were generally superior to those previously reported by our group, the terminal phase of chronic granulocytic leukemia still remains a formidable and generally refractory disease.  相似文献   
995.
996.
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998.
S B Tibrewal  M J Pearcy  I Portek  J Spivey 《Spine》1985,10(5):455-460
The significance of alteration of lumbar spinal motion in cases of herniated disc was examined using a three-dimensional x-ray technique (biplanar radiography) before and 3 months after discectomy. Fifteen consecutive cases of disc herniation were studied prospectively. Predictions of clinical examination, myelography, and motion study for the level and site of the lesion were correlated with the operative findings for their accuracy in localization of the lesion. Changes in lumbar spinal motion after surgery were also correlated with the clinical results. The clinical and myelographic predictions were similar to previously published studies. The present study showed that patients with a sequestrated or prolapsed disc lesion (as opposed to bulging disc) had an abnormally large lateral bend or axial rotation during flexion and extension at the level above, which reduced after surgery. Primary lumbar spinal motions (flexion and extension) were generally reduced to half of the normal value and were not significantly altered by surgery. The restriction of lumbar spinal motion was not significantly reflected in the clinical results, which were satisfactory in most cases. Discectomy by fenestration and minimal resection of the lamina did not produce instability.  相似文献   
999.
1000.
The apparent simultaneous presence of surface markers characteristic of both B and T cells is a phenomenon being described with increasing frequency in patients with chronic lymphocytic leukemia (CLL). We describe a patient with CLL whose B lymphocytes possessed surface immunoglobulin reactive with neuraminidase-treated sheep erythrocytes (SRBCs) and produced E rosette formation. Cytofluorography using monoclonal antibodies demonstrated the B cell nature of these cells and the absence of the SRBC receptor. Further documentation that the binding of SRBCs was mediated through immunologic reaction included E rosette formation inhibition by monospecific antisera and hemagglutination of SRBCs by a paraprotein isolated from the patient's serum. Fusion of the CLL cells with a human hypoxanthine-aminopterin- thymidine-sensitive plasma cell line resulted in the production of human hybridomas that secreted the SRBC-reactive IgM antibody. An analysis of clinical histories of CLL patients whose cells exhibited this phenomenon from both immunologic and clinical perspectives is presented.  相似文献   
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