40 research outputs found
The role of granulocyte-macrophage colony-stimulating factor in the pathogenesis of experimental murine leishmaniasis
Growth, interleukin-2 production, and responsiveness to IL-2 in T4- positive T Lymphocyte populations from malignant cutaneous T cell lymphoma (Sezary's syndrome): the effect of cyclosporin A
Quantitative representation of all t cells committed to develop into cytotoxic effector cells and/or interleukin 2 activity-producing helper cells within murine t lymphocyte subsets.
A Combination of Soluble Helper Factors Bypasses the Requirement for Stimulator Cells and Induces Nonspecific Cytotoxic T Cell Responses
Predictive validity of preoperative CT scans and the risk of pedicle screw loosening in spinal surgery
Pedicle screw fixation is the standard technique for the stabilization of the spine, a clinically relevant complication of which is screw loosening. This retrospective study investigates whether preoperative CT scanning can offer a predictor of screw loosening. CT-scan attenuation in 365 patients was evaluated to determine the mean bone density of each vertebral body. Screw loosening or dislocation was determined in CT scans postoperatively using the standard radiological criteria. Forty-five of 365 patients (12.3 %; 24 male, 21 female) suffered postoperative screw loosening (62 of 2038 screws) over a mean follow-up time of 50.8 months. Revision surgeries were necessary in 23 patients (6.3 %). The correlation between decreasing mean CT attenuation in Hounsfield Units (HU) and increasing patient age was significant (p < 0.001). Mean bone density was 116.3 (SD 53.5) HU in cases with screw loosening and 132.7 (SD 41.3) HU in cases in which screws remained fixed. The difference was statistically significant (p = 0.003). The determination of bone density with preoperative CT scanning can predict the risk of screw loosening and inform the decision to use cement augmentation to reduce the incidence of screw loosening