Objective To explore the relationship between Wuyishan cliff tea and esophageal cancer,and make integrated measures to prevent and control esophageal cancer.Methods A case-control study was conducted with a ratio of 1 to 1 and a health survey was conducted on objects which included 92 cases with histologically confirmed diagnoses of squamous-cell carcinoma of the esophagus and 92 controls matched by age,sex and resident.The analysis method of conditional logistic regression was used to analyze the influence of cliff tea on the development of esophageal cancer. Results The frequency of cliff tea drinking was 73.91% in cases with esophageal cancer compared with 84.78% in controls. As compared with subjects without tea drinking,subjects with cliff tea drinking significantly decreased the risk for developing esophageal cancer (P<0.05),and its OR were 0.60.The risk of esophageal cancer significantly reduced with increasing frequency of cliff tea drinking per week. Furthermore, we also found that the risk of esophageal cancer significantly reduced with the duration of cliff tea drinking and the early of beginning to drink cliff tea.Conclusion Wuyishan cliff tea drinking may protect against the risk of esophageal cancer.

Objective To explore the relationship between NAT2 genetic polymorphism and the risk of colorectal cancer. Methods A hospital-based case-control study was conducted and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to detect its genotypes.Results The frequency of NAT2 slow genotype was 19.58% in cases with colorectal cancer compared.with increased the risk for developing colorectal cancer and their OR were 2.16(95% CI:1.31～3.54).Conclusion The results suggest that NAT2 genetic polymorphism is associated with colorectal canoer susceptibility.People with NAT2 slow genotype have higher coloreetal cancer risk.

Objective To investigate the incidence and related risk factors of post-traumatic stress disorders (PTSD) after acci-dents in the Pearl River Delta .Methods Inpatients after accidents from April 2009 to February 2010 in seven hospitals of the Pearl River Delta cities ,such as Guangzhou ,Shenzhen and Zhuhai ,were surveyed with PTSD Checklist-Civilian Version (PCL-C) and self-made questionnaire .Results In a total of 554 post traumatic patients ,a prevalence of 28 .5% of PTSD symptoms were found in this region with 7 .8% (marks≥50) of severe degree and 20 .8% (marks :38-49) of mild to moderate degree .In the severe PTSD symptoms group ,the top three items were getting nervous and upset once faced similar situation ,difficulty sleeping or easy to be a-wake ,and the trauma experience caused recurring disturbing memory ,ideas or image .Multivariate analysis showed that female ,una-ble self-care ,incapable of working ,lack help from friends ,multiple injury ,and injury time longer were all associated with the PTSD symptom incidence .Conclusion The prevalence of PTSD symptoms is relatively high in injured patients after accidents in the Pearl River Delta .Early identification and intervention of PTSD symptoms in post-traumatic patients are important for the prevention of PTSD .