Objective To produce the experimental pig model of obstructive sleep apnea hypopnea syndrome(OSAHS) through raising pigs in the lower pressure container in order to study the effect of low pressure on morphology of upper respiratory soft tissue in pig.Methods The pigs were living in a container of low pressure for 6 months to make up the pig models of OSAHS.When the symptoms like OSAHS appearing and the pharyngeal respiratory pressure changing like the characteristics of OSAHS,the pigs were scanned by CT and compared with controls.Results The pharyngeal rear wall and soft palate in model pigs were thickened(0.94 cm?0.16 cm and 1.06 cm?0.23 cm respectively),while in control groups were(0.60 cm?0.11 cm and 0.59 cm?0.13 cm respectively).The cross-sectional area of upper airway in anterior,middle and rear parts were(1.49?0.12) cm2,(1.37?0.32) cm2 and(1.00?0.21) cm2 respectively,the narrowest part was in rear area,and in control groups were(1.30?0.14) cm2,(1.57?0.32) cm2 and(2.48?0.42) cm2 respectively.Conclusion The lower pressure condition can be used to produce animal experimental model of OSAHS,the low pressure is the important factor to cause OSAHS.

Objective To classify and grade the environments with Oncomelania hupensis snails inside embankment in marsh-land and lake areas,so as to improve the work efficiency and realize the systematic management. Methods The schistosomiasis endemic area Liaodi and Xiongdi villages in Jiangling County,Hubei Province were selected as the experiment villages,and the environments with snails in the two villages were divided into sections with a length of 500m,then the snail situation were sur-veyed by the systematic sampling method with 10m and 50m a frame respectively. The environments were classified according to the discovery of infected snails and wild fecal contamination,and the numbers of sites with snails and their areas in different class-es were recorded. Meanwhile,the data of sites with infected snails in Jingzhou City during the recent 5 years were collected and graded according to the average density of snails,so as to discuss the correlativity between the grades of environments with snails and the numbers of sites with infected snails and the occurrence rate of frames with snails. Results There were 1 967 sites with in-fected snails in Jingzhou City during the recent 5 years,and there was a positive correlation between the grades of environments with snails and the occurrence rate of frames with snails(rs=0.77,P<0.01),when the grade was 5,the constituent ratio of num-bers of sites with infected snails was 3.1%,and when the grade was 2-3,the ratio raised to 56.3%. There were 39 sites with snails in the two villages,the Class 1,2 and 3 environments included 1,18 and 20 sites,with the areas of 1 080,51 640 m2 and 41 220 m2 , respectively. There were no statistically significant difference between the grades divided by snail survey with 10m and 50m a frame(χ2=4.667,P>0.05),but the time-consuming of the former was 3 times of the latter. Conclusions The classification and grading of the environments with snails inside embankment in marshland and lake areas can master the key point of the snail survey. The subsection and setting frames at a suitable distance can save time and manpower,improve work efficiency,as well as understand the distribution of snail status of the environment with snails,which can realize the sort management of the snail envi-ronments inside embankment.