ABSTRACT
Objective To investigate subtle structural changes of white matter in patients with amnestic mild cognitive impair-ment (aMCI)using a tractography-based method.Methods Thirty patients with clinical diagnosis of aMCI and thirty-one cases of normal control(NC)and undergone diffusion tensor imaging.Cingulum (CG),corpus callosum (CC),uncinate fasciculus (UNC) and inferior occipitofrontal fasciculus (IOFF)were reconstructed,and fractional anisotrophy (FA)values were measured along these tracts using dTV II software.Differences of white matter tracts’FA values were explored between aMCI group and NC group.In addition,correlation analyses were also done between FA values and the MMSE(mini-mental state examination)scores in the aMCI patients.Results ① aMCI patients exhibited significant lower FA values in the bilateral CG,bilateral UNC and CC than NC group. Although there were no statistically significant differences,aMCI patients exhibited lower FA values than NC group in the left IOFF.② The FA values of right CG were positively correlated with MMSE scores.Conclusion Abnormal changes of FA values in CG,UNC and CC of aMCI patients suggest that subtle damages of white matter tracts related to memory exist in the prodromal phase of Alzheimer’s disease (AD).Fiber tractography has high sensitivity in detecting early damages of white matter.
ABSTRACT
The sere of 300 volunteer blood donors in Shanghai Area were tested for the hepatitis B surface antigens (HBsAg)and their antibodies(Anti- HBs)by ELISA technique.The posi- tive rates of test for both HBsAg and Anti-HBs were 12.66% and 33.6% respectively.The sensitivity of the testing method was 2ng/ml for HBsAg and 5mIU/ml for anti- HBs.In the meantime,the sera were also tested for HBsAg by RP- HA,which,gave the positive rate of only 5 %,with the fete of missed test being 8% as epmpared with the result given by ELISA.The prob- lems that are existing at present in test by ELISA were treated, suggesting that the quality control over the reagents and procedures involved must be carried out so that, the method mentioned above can become an effective means.In addi- tion,the significance of test for anti- HBs and anti-HBe in screening the blood donors was discussed.