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81.
Howard B. Yeon Jacob Weinberg Vincent Arlet Jean A. Ouelett Kirkham B. Wood 《European spine journal》2007,16(9):1379-1385
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4. 相似文献
82.
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84.
Istvn . Mrocz Kullervo Hynynen HLkon Gudbjartsson Sharon Peled Vincent Colucci Ferenc A. Jlesz 《Journal of magnetic resonance imaging : JMRI》1998,8(1):136-142
The aim of this study was to investigate a potential technique for image-guided minimally invasive neurosurgical interventions. Focused ultrasound (FUS) delivers thermal energy without an invasive probe, penetrating the dura mater, entering through the cerebrospinal fluid (CSF) space, or harming intervening brain tissue. We applied continuous on-line monitoring by MRI to demonstrate the effect of the thermal intervention on the brain tissue. For this, seven rabbits had a part of their skull removed to create access for the FUS beam into the brain through an acoustic window of 11 mm in diameter. Dura was left intact and skin was sutured. One week later, the rabbits were sonicated for 3 seconds with 21 W acoustic power, and the FUS focus was visualized with a temperature-sensitive T1-weighted MRI pulse sequence. The tissue reaction was documented over 7 days with T2-weighted images of the brain. The initial area of the central low signal intensity in the axial plane was .4 ± .3 mm2, and for the bright hyperintensity surrounding the lesion, it was 2.3 ± .6 mm2 (n = 7). In the coronal plane, the corresponding values were .4 ± .1 mm2 and 3.4 ± .9 mm2 (n = 5). The developing brain edema culminated 48 hours later and thereafter diminished during the next 5 days. Histology revealed a central necrosis in the white matter surrounded by edematous tissue with inflammatory cells. In summary, the image-guided thermal ablation technique described here produced a relatively small lesion in the white matter at the targeted location. This was accomplished without opening the dura or the need for a stereotactical device. MRI allowed on-line monitoring of the lesion setting and the deposition of thermal energy and demonstrated the tissue damage after the thermal injury. 相似文献
85.
The Proceedings of the Round Table Conference will be published as volume 19, in the series Update in Intensive Care and Emergency Medicine (Springer Verlag) in January, 1995. 相似文献
86.
A case of deliberate ingestion of clothes washing liquid and fabric conditioner is described. Tracheal intubation and controlled ventilation became necessary because of respiratory muscle dysfunction associated with hypocalcaemia. We suggest that the phosphate component of the clothes washing liquid was responsible for the dramatic metabolic upset and subsequent need for admission to the Intensive Care Unit. 相似文献
87.
CpG DNA functions via the toll-like receptor-9 (TLR-9) receptor, inducing B cell proliferation and promoting immunoglobulin production. B cell responses to CpG DNA-containing immune complexes could be important in chronic autoimmunity and immune responses to bacterial components. Therefore, we investigated the potential synergy of CpG DNA-stimulation with FcgammaR clustering (CFR) on splenic B cell activity. CFR-induced splenocyte proliferation was significantly increased compared to treatment with CpG DNA alone. While the levels of interleukin-10 (IL-10) were increased in CpG DNA-treated splenocyte cultures, particularly following FcgammaRII/III-clustering, CFR treatment reduced IL-6 levels. B-cell maturation in culture was enhanced by CFR. Indeed, the frequency of IgG expressing cells after stimulation with CpG DNA was increased and was even higher after CFR stimulation. Furthermore, the frequency of plasma cell precursors was markedly increased by stimulation with CFR. Late splenic B cell subsets, transitional type 2 (T2) and mature (M) B cells, responded strongly to CpG DNA with proliferation and the response was enhanced by FcgammaR-clustering. Immature transitional type 1 (T1) B cells showed distinctly lower proliferative response to CpG DNA and very small effects of FcgammaR-clustering, despite similar expression of Fcgamma-receptors by all B cell subsets. In conclusion, these data show synergistic impact of CpG DNA and simultaneous FcgammaR-clustering on B cell proliferation and differentiation. 相似文献
88.
Lung surfactant gelation induced by epithelial cells exposed to air pollution or oxidative stress 总被引:1,自引:0,他引:1
Anseth JW Goffin AJ Fuller GG Ghio AJ Kao PN Upadhyay D 《American journal of respiratory cell and molecular biology》2005,33(2):161-168
Lung surfactant lowers surface tension and adjusts interfacial rheology to facilitate breathing. A novel instrument, the interfacial stress rheometer (ISR), uses an oscillating magnetic needle to measure the shear viscosity and elasticity of a surfactant monolayer at the air-water interface. The ISR reveals that calf lung surfactant, Infasurf, exhibits remarkable fluidity, even when exposed to air pollution residual oil fly ash (ROFA), hydrogen peroxide (H2O2), or conditioned media from resting A549 alveolar epithelial cells (AEC). However, when Infasurf is exposed to a subphase of the soluble fraction of ROFA- or H2O2-treated AEC conditioned media, there is a prominent increase in surfactant elasticity and viscosity, representing two-dimensional gelation. Surfactant gelation is decreased when ROFA-AEC are pretreated with inhibitors of cellular reactive oxygen species (ROS), or with a mitochondrial anion channel inhibitor, as well as when A549-rho0 cells that lack mitochondrial DNA and functional electron transport are investigated. These results implicate both mitochondrial and nonmitochondrial ROS generation in ROFA-AEC-induced surfactant gelation. A549 cells treated with H2O2 demonstrate a dose-dependent increase in lung surfactant gelation. The ISR is a unique and sensitive instrument to characterize surfactant gelation induced by oxidatively stressed AEC. 相似文献
89.
Serge Perrot Vincent Calvez Jean-Paul Escande Nicolas Dupin Anne-Geneviève Marcelin 《Journal of clinical virology》2003,28(2):165-168
BACKGROUND: Sj?gren's syndrome (SS) is an autoimmune exocrinopathy associated with multiple autoantibodies, lymphocyte infiltration of various organs, and functional deficiency of T cells. Several viruses have been implicated by PCR based studies, but their contribution to the pathophysiology of SS is still controversial. OBJECTIVES: In an attempt to explore the presence of human herpesviruses DNA sequences in salivary glands biopsies from patients suffering of SS, a recently developed strategy based on PCR with consensus degenerated primers that allowed to detect known and eventually unknown herpesviruses was used. STUDY DESIGN: Salivary glands biopsies from 55 patients suffering of primary and SS syndrome were explored by herpesviruses consensus PCR primers and all the PCR products were sequenced. RESULTS: Nine out of 55 salivary glands were positive by PCR and sequence analyses allowed to identify Epstein-Barr virus (EBV) in 6 cases and herpes simplex virus (HSV)-1 in 3 cases. We did not detect any sequences that could be related to a new herpesvirus. CONCLUSION: In view of the good sensitivity of the technique used, our study is not consistent with SS being associated with an unknown herpesvirus. However, our results suggest that EBV and HSV-1 could be implicated in a subset of SS cases and this possibility needs to be explored, to assess the potential benefit of antiviral drugs in some cases. 相似文献
90.
Chitti R. Moorthy J. Rao Nibhanupudy Ebrahim Ashayeri Alfred L. Goldson Maria C. Espinoza Joseph J. Nidiry Oswald G. Warner Vincent J. Roux 《Journal of the National Medical Association》1982,74(3):261-266
The objective of radiotherapeutic management in esophageal cancer is to accomplish maximum tumor sterilization with minimal normal tissue damage. This sincere effort is most often countered by the differential in tumor dose response vs normal tissue tolerance. Intraluminal isotope radiation, with its inherent advantage of rapid dose falloff, spares the lungs, the spinal cord, and other vital structures, yet yields adequately high doses to esophageal tumor. Though in existence since the turn of the century, the method of intracavitary radium bougie application dropped out of favor due to technical difficulties imposed by the size of the radium source and radiation exposure to the personnel involved. The authors describe a simple “iridium 192 afterloading intraluminal technique” that eliminates technical problems and reduces radiation exposure considerably. 相似文献