黑龙江地区幽门螺杆菌毒力基因型与胃十二指肠疾病关系的研究

幽门螺杆菌（Hp）感染除与宿主和环境因素有关外，菌株的毒力差异对临床结果的影响也是不可忽视的因素。Hp基因亚型的分布具有明显的地域性，地理差异在导致不同临床结局中所起的作用仍是当前研究的热点。本研究旨在阐明Hp主要毒力基因亚型在黑龙江地区的分布情况及其与胃、十二指肠疾病的关系。

Distribution of virulence-associated Helicobacter pylori isolates from Heilongjiang province and the association with gastroduodenal diseases

Objective Through introduction of principal theory and algorithm of propensity score to design SAS macro programs for binary data.Methods Propensity score method was used to compare the differences of character variables between two groups, and the association of DNR (Do Not Resuscitate) with the mortality of congestive heart failure was evaluated with different methods.Results Significant differences among the character variables between two groups were effectively balanced with stratification or matching method. The odds ratios of DNR with the in-hospital mortality rate of congestive heart failure were estimated identical with different algorithms and to find that the association of DNR to in-hospital mortality was highly significant. Conclusions Propensity score was a good algorithm that could be used to analyze any kind of observational data for matching the effects among the character variables.