AIM: To find the optimum extraction of volatile oil. METHOD: To extract the volatile oil by steam distillation or supercritical fluid extraction (SFE). RESULT: (1) The optimum extraction of volatile oil extracting by steam distillation is: Ligustricum Chuanxiong Hort.:Soak time 12 hrs, thin powder, extract time 3hrs, and to add water with 1∶10; Alpinia Officinarum Hance: Soak time 0 hr, thick powder, extract time 3 hrs, and to add water with 1∶10; Curcuma Wenyujin Y.H. chen C. Ling: Soak time 24hrs, mild powder, extract time 1.5hrs, and to add water with 1∶5; Notopterygium incisum Ting: Soak time 0 hr, thick powder, extract time 3 hrs, and to add water with 1∶10. (2) The best condition of volatile oil extracting by SFE is: Ligustricum Chuanxiong Hort.: 60℃, thin powder, press 25MPa, extract time 1.5hrs; Alpinia Officinarum Hance: 60℃, mild powder, press 25MPa, extract time 0.5hr; Curcuma Wenyujin Y.H. chen C. Ling: 60℃, thin powder, press 20MPa, extract time 1 hr; Notopterygium incisum Ting: 60℃, thin powder, press 25MPa, extract time 1hr. CONCLUSION: Supercritical fluid extraction (SFE) is superior to steam distillation.

Various questionnaires for screening diabetes in Chinese population were evaluated. Two questionnaires (Finnish Diabetes Risk Score and Danish Diabetes Risk Score) were applied. Sensitivity, specificity and the area under the receiver operating characteristic (ROC) curve (AUC) for both questionnaires were calculated. The AUCs were 0. 760 (95% CI: 0.713-0.806) for the Finnish questionnaire (P<0.01) and 0.706 (95% CI: 0.647-0.764) for the Danish one (P<0.01). The sensitivities, specificities and predictive values of both questionnaires were not so good in the present survey as in the published reports. It suggests that these screening questionnaires must be modified to suitable for Chinese population.

Objective To evaluate the molluscicidal effect of black plastic mulching in mountainous areas of Yunnan Prov-ince. Methods In Leqiu Village,Nanjian County,Yunnan Province,the terraced fields with Oncomelania hupensis snails were divided into A,B,C,D,E groups,and of which,A,B,C,D groups,as the experimental groups,were administered with sim-ple black plastic mulching for 30 days,60 days,90 days and 120 days respectively;Group E,as the control group,was adminis-tered with 50%niclosamide ethanolamine salt wettable powder spraying. Results In Group C and D(simple black film mulching for 90 days and 120 days),no snails were found after the administration,the average density of living snails decreased by 100%, and the cost of one year was similar to that of the control group. Conclusion The molluscicidal effect of black plastic mulching is good in mountainous areas.