Objective:Our aim was to study the levels of atrial natriuretic peptide (ANP) and pulmonary perfusion imaging in determining of pulmonary artery hypertension (PAH). Methods: We measured ANP levels by using radioimmunoassay after making various types of PAH in rabbits. Catheterization and pulmonary perfusion tomographic imaging were used in the control group. Results: When the pulmonary artery pressure increased slightly, the ANP levels were lower in PAH group than that of control group, but the difference was not significant (t=1, P>0.05). At the same time, pressure measured by catheterization did not change as the control group, but the ratio of back/abdomen radiopharmaceuticals distribution which was measured with pulmonary perfusion tomographic imaging was significantly higher in PAH group than that of the control (t=2.5, P<0.05). The difference between the ANP levels when the pulmonary artery pressure increased medially and seriously was significant (t＝4.0 and 6.5, P＜0.05). The other two methods got the same result (P＜0.05). Results of three examining methods were positively related. Conclusion:The ANP levels can determine the degree of PAH, and it was simple. But it was not as sensitive as that of pulmonary perfusion tomographic imaging.

Objective To evaluate the effects of 3 molluscicides namely 5%niclosamide ethanolamine granules,4%“Luo-wei”(Tea-seed distilled saponins,TDS)and 50%wettable powder of niclosamide ethanolamine salt(WPN)by spraying and pou-drage methods in marshland and lake regions in dry season. Methods An environment with a high snail density was chosen as the experimental field,then the spraying and poudrage experiments were carried out in the field to assess the molluscicidal effects of 5%niclosamide ethanolamine granules,TDS and WPN delivered by spraying and poudrage methods with a concentration of 30, 6 and 2 g/m2,respectively,and the molluscicidal effects of the 3 drugs by the two methods were evaluated and compared in differ-ent time. Results After the delivery for 15 d,the adjusted snail death rates of the 5%niclosamide ethanolamine granules,TDS and WPN in the spraying experiment were 79.00%,82.29%and 84.83%,respectively,and those in the poudrage experiments were 97.42%,95.27% and 96.62%,respectively. Conclusion The molluscicidal effect of poudrage method is better than the spraying method,and the former is worthy of further extension and application in the marshland in dry season.