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目的探讨脊髓运动诱发电位(SCMEP)在脊髓肿瘤手术中监测的应用价值.方法采用硬膜外电极在椎管内直接刺激脊髓记录脊髓运动诱发电位(SCMEP)监测脊髓肿瘤手术,并对17例肿瘤患者的手术监测的记录结果进行回顾性分析.结果SCMEP由于病变部位及性质、刺激电极与记录电极间的距离不同,波幅及潜伏期的差异较大,电极安放后与手术结束时的结果个体对照,相差不显著(P=0.083;P=0.387).7例术中波幅降低超过预警值20%,5例经短暂休息或改变手术方向后,波幅恢复正常.结论SCMEP的波幅变化是提示脊髓损伤的可靠性灵敏指标,对辅助医生进行手术安全操作,缩短手术时间,提高手术质量,减少术后神经功能障碍起到重要作用.  相似文献   
23.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
24.
The tumor microenvironment consists of tumor, immune, stromal, and inflammatory cells which produce cytokines, growth factors, and adhesion molecules that promote tumor progression and metastasis. Of particular interest in this setting is interleukin-1 (IL-1), a pleiotropic cytokine with numerous roles in both physiological and pathological states. It is known to be up regulated in many tumor types and has been implicated as a factor in tumor progression via the expression of metastatic and angiogenic genes and growth factors. A number of studies have reported that high IL-1 concentrations within the tumor microenvironment are associated with a more virulent tumor phenotype. Solid tumors in which IL-1 has been shown to be up regulated include breast, colon, lung, head and neck cancers, and melanomas, and patients with IL-1 producing tumors have generally bad prognoses. The exact mechanisms by which IL-1 promotes tumor growth remain unclear, though the protein is believed to act via induction of pro-metastatic genes such as matrix metalloproteinases and through the stimulation of adjacent cells to produce angiogenic proteins and growth factors such as VEGF, IL-8, IL-6, TNFα, and TGFβ. The IL-1 receptor antagonist (IL-1ra) is a naturally occurring inhibitor to IL-1 and acts by binding to the IL-1 receptor without activating it. The protein has been shown to decrease tumor growth, angiogenesis, and metastases in murine xenograft models. Our focus in this review is to summarize the known data on the role of IL-1 in tumor progression and metastasis and the use of IL-1 inhibition as a novel therapeutic approach in the treatment of solid organ malignancies.  相似文献   
25.
颅内肿瘤是中枢神经系统常见病,它包括起源于颅内各种组织的原发性肿瘤及其他部位转移到颅内的继发性肿瘤。颅内肿瘤的诊断主要依靠影像学检查,伴随现代高科技的发展,常规影像学技术也正在发生着日新月异的进步,颅内肿瘤的诊断准确度越来越高。本文主要介绍颅内常见肿瘤的普通X线、CT、MRI图像特点及影像学进展。  相似文献   
26.
心脏穿透伤是心胸外科的特急重症,占到胸部外伤的 2%~396,据报道院外死亡率为62%~8496,入院后死亡率为15%,且有日益增高的趋势。我科1998年9月- 2005年4月共收治心脏穿透伤18例,取得一定的救护经验, 现报道如下。  相似文献   
27.
王辉 《辽宁医学杂志》2004,18(5):227-230
1 大肠癌的治疗原则实践证明 ,大肠癌根治术后约 5 0 %未治愈 ,主要是术前发生远隔转移和术后复发所致。为消灭这些微小病灶而进行化疗 ,为预防术后复发进行放疗 ,生物治疗、中药治疗能提高机体免疫力从而提高疗效。大肠癌的生物学特性是对放化疗不敏感 ,所以多学科合作治疗肿  相似文献   
28.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
29.
脱细胞尿道及其海绵体基质制备的实验研究   总被引:1,自引:0,他引:1  
目的 探索脱细胞尿道及其海绵体基质的制备方法。方法取健康壮年兔完整尿道及其海绵体组织,以Triton-X100与NH3H2O联合提取法进行脱细胞处理。标本做HE染色,组织学观察分析脱细胞效果。结果脱细胞处理11天后,成功获得脱细胞及其海绵体基质,所得基质外观良好。HE染色观察无细胞存在。弹力纤维排列规整,间隙较大,结构无破坏。结论利用Triton-X100与NH3H2O联合提取法可成功制备完整无细胞尿道及其海绵体基质,为尿道再造修复提供崭新思路。  相似文献   
30.
本文研究了去除金属离子的金属硫蛋白(ApoMT)对镉金属硫蛋白(CdMT)肾毒性作用的影响。结果发现,与单独给予CdMT比较,ApoMT能降低尿蛋白量和尿碱性磷酸酶(AKP)活性,并能促进尿Cd的排泄。肾组织形态学结果显示肾近曲小管损伤程度明显减轻。提示ApoMT对CdMT肾小管损伤具有保护作用。  相似文献   
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