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991.
Hydroxyapatite deposition disease 总被引:2,自引:0,他引:2
992.
Scintigraphic assessment of bone islands 总被引:1,自引:0,他引:1
993.
994.
Spinal cord central echo complex: histoanatomic correlation 总被引:1,自引:0,他引:1
Real-time sonography consistently demonstrates an echo complex centrally located in the spinal cord. This echogenic focus is currently attributed to the central canal. The authors sought the source of this central echo with ultrasound (US) and histoanatomic study of both fresh and fixed cadaver spinal cords. Correlative transverse sections of the spinal cord were stained with hematoxylin-eosin and Luxol fast blue for cells and myelin and with Holzer stain for glial fibrils. The central echo complex is produced by the interface between the myelinated ventral white commissure and the central end of the anterior median fissure. Variations in the shape of the central complex seem to reflect varying degrees of flaring of the central end of the anterior median fissure. The inconstant residual central canal and islands of residual ependymal cells are clearly not the source of the central echo complex. 相似文献
995.
The opacified maxillary sinus: CT findings in chronic sinusitis and malignant tumors 总被引:2,自引:0,他引:2
To distinguish opacification owing to inflammatory conditions (sinusitis) from that caused by nasomaxillary malignancy, computed tomography scans in 24 proved cases of sinusitis or tumor were reviewed for features related to sinus size, wall thickness, and character of bone erosion. An anatomic system was defined for classifying lesions according to the surface and type of bony involvement. In 12 cases of chronic maxillary sinusitis, the involved sinus was usually small and thick walled. The nasal surface of the involved sinus usually was eroded; often the orbital surface was eroded. The erosion was, however, short, irregular, and in the region of a normal dehiscence (semilunar hiatus or infraorbital canal) in all cases. The infratemporal surface was never eroded. In 12 cases of nasomaxillary neoplasia, the sinus was enlarged, one or more walls of the involved sinus being thinned and expanded. Bone erosion was present in all cases; erosion of the infratemporal surface was specific for neoplasia and significant as the usual site of recurrence. 相似文献
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997.
The authors report a case of acute renal failure resulting from acute cortical necrosis. A selective renal angiogram defined a very unusual, abrupt termination of vascularity at the interlobular and arcuate levels. Nephro-angiography is an important tool in the diagnosis of acute cortical necrosis in the initial phase of acute renal failure. 相似文献
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HF Pabst DW Spady LM Pilarski MM Carson JA Beeler MP Krezolek 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(12):1291-1297
Spontaneous integrin expression on CD4+, CD8+ and CD19+ lymphocytes at 6 months was significantly lower in breastfed than formula-fed infants ( p < 0.05). In another study of 59 formula-fed and 64 breastfed 12-month-old children blast transformation and cytokine production by lymphocytes, and T cell changes were measured before and after measles-mumps-rubella vaccination (MMR). Before vaccination, lymphocytes of breastfed children had lower levels of blast transformation without antigen ( p < 0.001), with tetanus toxoid ( p < 0.02) or Candida ( p < 0.04), and lower interferon-γ production ( p < 0.03). Fourteen days after the live viral vaccination, only the breastfed children had increased production of interferon-γ ( p < 0.02) and increased percentages of CD56+ ( p < 0.022) and CD8+ cells ( p < 0.004). These findings are consistent with a Thl type response by breastfed children, not evident in formula-fed children. Feeding mode has an important long-term immunomodulating effect on infants beyond weaning. 相似文献