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91.
After a brief presentation of the development of free walking interpreted as learning dynamical equilibrium, the problem of sensory integration in the process of walking development is discussed. A critical review of the role of vision in the development of posturo-locomotor task is presented, along with recent test results on the development of the vestibular system. A final section presents the development of head stabilization and coordination as a necessary means to assist sensory integration. It is suggested that if sensory information is necessary to enhance posturo-locomotor skills, a good mastery of walking is in turn necessary to increase the efficiency of sensory integration. 相似文献
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GL Kay GW Sun A Aoki CA Prejean 《Canadian Metallurgical Quarterly》1995,60(6):1640-50; discussion 1651
BACKGROUND: Preoperative ejection fraction (EF) has been shown to adversely affect postoperative hospital mortality and morbidity for patients undergoing isolated coronary artery bypass grafting. METHODS: To investigate influence of EF on isolated coronary artery bypass grafting outcomes (overall hospital mortality, hospital cardiac mortality, hospital morbidity, and hospital costs), data were reviewed from 1,354 consecutive patients who underwent isolated coronary artery bypass grafting between January 1, 1990, and April 30, 1992, at a single nonprofit hospital. Overall hospital mortality was 4.06% (cardiac, 2.36%). Hospital morbidity was 14.25% (including mortality). Hospital costs (not charges) averaged $16,673 per patient. To explore the impact of preoperative EF, EF was stratified into regular intervals. Each interval was then compared with regard to hospital mortality, morbidity, and average costs. A new statistical tool, discharge analysis, was developed to analyze the cost data. This was necessary because previous efforts at cost analysis have used tools inappropriate for real world cost data. RESULTS: The statistical analysis showed that patients with EF of 0.40 or greater had the best outcomes (lowest mortality, morbidity, and cost). Once the EF is 0.40 or greater the EF does not carry further predictive value. At EF less than 0.40, patients with EF less than 0.30 have a poorer outcome than patients with EF of 0.30 to 0.39. CONCLUSIONS: (1) Ejection fraction is a valid predictor of mortality, morbidity and resource utilization based on statistical analysis. (2) Patients can be broadly grouped as having EF greater than 0.40, less than 0.30, or from 0.30 to 0.39 with regard to clinical and cost outcomes. (3) Postoperative length of stay is not predicted by risk-adjusted EF. (4) A new tool, discharge analysis, is presented to facilitate cost analysis. 相似文献
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GL Solomon 《Canadian Metallurgical Quarterly》1994,102(8):632-635
95.
H Lin ML Bondy LA Langford KR Hess GL Delclos X Wu W Chan MA Pershouse WK Yung PA Steck 《Canadian Metallurgical Quarterly》1998,4(10):2447-2454
The frequency of loss of heterozygosity (LOH) around MMAC/PTEN and DMBT1 loci and survival analyses based on the LOH status were assessed in 110 patients with different histological groups of gliomas. Twenty-six of the patients had anaplastic oligodendrogliomas, 31 had anaplastic astrocytomas, and 53 had glioblastomas multiforme (GM). At the DMBT1 locus, LOH was observed very frequently in all three histological groups, with no significant difference in the frequency of LOH among the three histological groups. At the MMAC/PTEN locus, patients with GM exhibited a significantly increased frequency of LOH (72%) compared with patients with anaplastic astrocytomas (29%) or anaplastic oligodendrogliomas (31%) (P < 0.0001). Kaplan-Meier survival plots showed that patients with LOH at the MMAC/PTEN locus had a significantly worse prognosis than did patients without LOH at the MMAC/PTEN locus [hazard ratio (LOH versus non-LOH), 2.65; 95% confidence interval (CI), 1.69-4.46; P < 0.0001]. Cox proportional hazards regression analysis, adjusted for age at surgery and histological grades (GM and non-GM), showed that LOH at the MMAC/PTEN locus was a significant predictor of shorter survival [hazard ratio (LOH versus non-LOH), 2.01; 95% CI, 1.1-3.5; P = 0.018). Our analysis failed to indicate a similar association between the frequency of LOH at the DMBT1 locus and patient survival [hazard ratio (LOH versus non-LOH), 2; 95% CI, 0.37-3.13; P = 0.2]. These results suggest that the DMBT1 gene may be involved early in the oncogenesis of gliomas, whereas alterations in the MMAC/PTEN gene may be a late event in the oncogenesis related to progression of gliomas and provide a significant prognostic marker for patient survival. 相似文献
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The purpose of this study was to examine how antigen retrieval affected the yield of immunogold labeling on epoxy sections based on embedding with different amounts of accelerator. The concentration of accelerator DMP-30 (tri(dimethyl amino methyl) phenol) was varied in the range of 0-8% in the processing of the tissue for epoxy embedding. Immunogold labeling was performed on epoxy sections and LR-White sections of fibrin clots and renal tissue with IgG-deposits, and the antibodies used were anti-fibrinogen anti-IgG and, respectively. For some of the sections antigen retrieval was performed by heating the sections in citrate buffer. In all cases, the yield of immunogold labeling increased following antigen retrieval. The increase (%) in the yield of immunogold labeling as a result of antigen retrieval was larger for epoxy sections than for LR-White sections. The immunolabeling on high-accelerator epoxy sections exposed to antigen retrieval was about 20% more intense than on untreated LR-White sections both for IgG and fibrinogen. In addition to breaking fixations bonds introduced by the chemical fixation, we believe that the antigen retrieval also breaks bonds between the epoxy resin and the embedded tissue. The combination of increased amount of accelerator during tissue processing for epoxy embedding and antigen retrieval by heating in citrate buffer is a potent method for increasing specific immunolabeling on epoxy sections. 相似文献
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G Schuhmachers K Ariizumi T Kitajima D Edelbaum S Xu RK Shadduck GL Gilmore RS Taylor PR Bergstresser A Takashima 《Canadian Metallurgical Quarterly》1996,106(5):1023-1029
We have established long-term dendritic cell lines from the epidermis of newborn mice. These cell lines (XS series) proliferate maximally in response to granulocyte/macrophage-colony stimulating factor, as well as to CSF-1, which is produced by skin-derived NS fibroblast lines and by keratinocytes (albeit in smaller amounts). The purpose of this study was to examine the impact of UVB radiation on CSF-1-mediated interaction of dendritic cells with fibroblasts and keratinocytes. Exposure of NS cells to UVB radiation (unfiltered FS20 sunlamp) decreased CSF-1 production at mRNA and protein levels. Both changes occurred in a dose-dependent fashion, with 50 J/m2 causing a significant reduction. UVB radiation also downregulated CSF-1 mRNA expression by Pam 212 keratinocytes. UVB exposure of XS cells diminished the surface expression of CSF-1 receptors, with 50 J/m2 causing a significant reduction. Thus, UVB radiation interrupts CSF-1-mediated cell-cell interaction by a dual mechanism: downregulating CSF-1 production and abrogating CSF-1 receptor expression. Importantly, granulocyte/macrophage-colony stimulating factor receptor expression by XS cells was also inhibited by UVB radiation, once again, with 50 J/m2 producing significant inhibition. We propose that the resulting CSF-1 deficiency in epidermal microenvironment and unresponsiveness by dendritic cells to relevant growth factors may contribute to UVB-mediated loss of resident epidermal dendritic cells (i.e., Langerhans cells) in skin. 相似文献