ABSTRACT
Objective To study the effects on tissue CT number caused by scan protocols.Methods The phantom was repeatedly scanned in different protocols by changing only one of parameters,such as X-ray tube voltage,mAs and recon kernel,while other parameters were ketp unchanged.The CT number of different materials in phantom were measured and analyzed.Results The CT numbers of tissues changed remarkably with the tube voltage and had different relativity for different tissues.The CT numbers had positive correlation with kV for such maierials as polyethyle,lexan,perspex,but for teflon the correlation was negative.The mAs and recon kernel had no effects on CT number.Conclusions The CT number of tissue changes with scanning X-ray tube voltage,so the setting of scan parameters should be taken into account in image diagnosis and radiotherapy.
ABSTRACT
Objective To measure the correlation between the levels of blood serum nitric oxide(NO) ,the activity of nitric oxide synthetase(NOS) and depression.Methods 136 patients with depression were diagnosed by CCMD-3 and 120 healthy control subjects were included in the study.NO and NOS levels in blood serum of both groups were tested, and the variation of NO and NOS between the two groups were compared.Results The blood se-rum NO levels[ (70.05±10.34)μmol/L w.(67.17±16.52) μmol/L] and the activity of NOS [(29.49±5.12)U/L vs.(26.99±2.87) U/L] in the patients with depression were significantly higher than those in the control group(P<0.05).The blood serum NO levels and the activity NOS in the treatment patients was lower than the oth-er patients[(74.42±8.80) μmol/L vs.(78.81±12.28) μmol/L;(27.71±5.46)U/L vs.( 30.49±4.65 )U/L,P <0.05].Conclusion The blood serum NO levels and the activity of NOS increase in the patients with de-pression.NO might be involved in the pathogenesis of depression.The antidepressants might descend the NO levels so to relieving depression.