Objective To study dynamic change for the prevalence of the hyperlipidemia and the plasma lipids level of staff and workers in group in China Ocean Petroleum so as to provide the evidence for the prevention of the patients suffered from hyperlipidemia. Method Four thousand eight hundred and nin-ty-nine workers fmished blood fat test and blood fat data separately for two times in 1998 and 2004. Results The TC average value of males rose to (5.68 ± 0.99) mmol/L from (5.46 ± 1.08) mmol/L and the TC av-erage value of females rose to (5.79 ± 0.99) mmol/L from (5.42 ± 1.04) mmol/L,both were statistical sig-nificant difference(P < 0.01 ).The TG average value of males rose to ( 1.65 ± 1.31 ) mmol/L from ( 1.48 ± 1.29) mmol/L and the TG average value of females rose to (1.46 ± 1.09) mmol/L from (1.28 ± 1.17) mmol/L,both were statistical significant difference (P < 0.01 ). The gross hyperlipidemia,HTC,HTG rate rose to 58.9%,45.1%,32.4% from 46.2%,32.1%,25.7% for the males and those rose to 58.0%,49.6%,26.2% from 42.0%,31.2%,19.3% for the females ,all were statistical significant difference (P < 0.01 ).After 6 years,the males control rate of the HTC and HTG were 27.5% and 29.9%,the females control rate of the HTC and HTG were 25.1% and 34.0%. Conclusions The staff and workers suffered from high hyperlipidemia and lipid level is higher in man group in China Ocean Petroleum and also faster. Treatment control rate of hyperlipidemia was very lower .Therefore,the prevention measure must be taken as fast as possible to reduce lipid level and hyperlipidemia patient's rate actively and improve control rate.

Objective To investigate the stress distribution in various tooth heights of ferrule effect in post crown,and to evaluate the biomechanical mechanism in post crown.Methods The three-dimensional finite element entity grid model was constructed,which was a maxillary central incisor restored with post and porcelain fused to metal crown (PFM crown).By imitating the various tooth heights under static loading,the dentin stress was analyzed.Results The stress distribution had an increasing tendency from tooth cervix to root,but it could be decreased by ferrule structures and the decrease degree accorded with the region and height of ferrule.The ferrule effect of the wrapping 1 cm coronal tooth could decrease the stress of the tooth cervix obviously but 2 cm decreased a little.Conclusion The crown wrapping 1 cm coronal can produce ferrule effect obviously and protect the tooth.We can choose to use crown wrapping 2 cm coronal to care the tooth condition.