[Spatiotemporal variation analysis and identification of water pollution sources in the Zhangweinan River basin].

In this study, several statistical methods including cluster analysis, seasonal Kendall test, factor analysis/principal component analysis and principal component regression were used to evaluate the spatiotemporal variation of water quality and identify the sources of water pollution in the Zhangweinan River basin. Results of spatial cluster analysis and principal component analysis indicated that the Zhangweinan River basin can be classified into two regions. One is the Zhang River upstream located in the northwest of the Zhangweinan River basin where water quality is good.

[The relationship between polymorphism of genes XPA, XPC, XPD, XRCC1 and susceptibility to acute lymphoblastic leukemia].

Objective: To study the relationship between polymorphism of genes XPA, XPC, XPD, XRCC1 and susceptibility to acute lymphoblastic leukemia (ALL) in a Chinese population.

Methods: Polymorphism were determined by a case-control study through matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry method of Mass-ASSAY platform in 114 confirmed ALL cases and 169 age- and sex-matched controls, so as to compare the relationship between different genotypes and ALL risk.

Results: Multivariate logistic regression analysis revealed that individuals carrying at least one 23G variant allele (AG/GG genotypes) had a significantly increased risk for ALL (adjusted OR 2.