Racial differences in survival of patients on dialysis

BACKGROUND: Recent studies have documented racial differences in the crude mortality rates of patients on dialysis. However, proper interpretation of these findings requires adjustment for potential confounders and comorbid risk factors between the racial groups. METHODS: We examined the clinical data on 3752 Caucasian patients, 451 Southeast Asian patients, 322 South Asian patients, and 319 black patients who were treated with hemodialysis or peritoneal dialysis under a Universal Health Care system in Toronto and prospectively followed between 1981 and 1995. In all patients, a number of comorbid risk factors for survival was assessed at the start of dialysis and was reassessed with their outcome status (that is, continued dialysis, transplantation, death, or loss to follow-up) at least every six months. Cox proportional hazards analysis was used to fit multivariate models predicting patient survival. Pairwise comparisons of the relative hazards of death between the racial groups were performed after stratifying for cardiovascular disease, diabetes mellitus, and hypertension at the start of dialysis, and were adjusted for differences in other comorbid risk factors. RESULTS: The risk of death in Caucasian patients was significantly increased when compared with Southeast Asian patients, South Asian patients, and black patients [multivariate relative hazards (95% CI): 1.63 (1.36 to 1.97), 1.36 (1.07 to 1.73), 1.34 (1.07 to 1.67), respectively]. Additionally, we detected an interaction between race and cigarette smoking (P < 0. 004), suggesting that in the dialysis patients who smoked, whites had a higher mortality risk compared with non-whites. CONCLUSIONS: Differences in patient survival on dialysis exist between racial groups. However, the genetic and environmental determinants that underlie these differences are presently unknown.     

钛基底对钛-瓷修复体表面色的影响

目的　探讨钛金属基底对钛 -瓷修复体表面色是否有明显影响。方法　制作 Dentsply DETREY- Carat瓷粉与钛 -瓷修复体标准试件 ,用 CS- 5型分光光度计测色 ,统计分析测定结果 ,并计算色差。结果　钛金属基底与Ni- Cr金属基底间颜色差异较大 ,但加不透明瓷及牙体瓷后 ,两组试件各色度指标统计学上无显著性差异 ,色差均小于 1.5。结论　钛金属基底对钛 -瓷修复体表面色无明显影响 ,Dentsply两种瓷粉同色瓷间无明显颜色差异。     

实验性犬侧颅底骨缺损修复材料的研究

为达到修复颅底骨硬脑膜缺损的目的，通过手术造成狗侧颅底骨及硬脑膜大面积缺损模型，利用自体阔筋膜或与细胞生长促进因子－骨形成蛋白进行修复，观察移植后不同时期所修复组织的成活及成骨的组织学变化情况，探讨了阔膜修复硬脑膜后组织学变化，证实生物膜与骨形成蛋白是一种理想的颅底缺损修复材料，为临床修复硬脑膜、颅底缺损等提供了参考。     

听神经瘤的再手术（附11例分析）

为进一步提高听神经瘤手术的临床疗效，对１５８例听神经手术后１１例再次手术患者进行临床分析，发现肿瘤大小，切除方式以及手术进路与临床症状复发密切相关，肿瘤越大，复发机会越多；大部切除；次全切除及全切除的复发再手术率分别是１９．４％、１３．２％和０，迷路后进路手术复发再手术率最高，达３３．３％，防止临床复发最根本的措施是术中尽量减少肿瘤残留，力争全切。为达此目的要求早期诊断，选择适当的手术进路，对不能