Objective To explore the correlation between dual energy imaging indices,microvessel densi-ty(MVD),vascular endothelial growth factor(VEGF)and lung cancer lymph nodes metastasis and its practical sig-nificance by applying dual source CT(DSCT)dual energy imaging.Methods 62 cases of non-small cell lung can-cer(NSCLC)were underwent DSCT dual energy imaging and divided into groups with and without lymph node me-tastasis according to the results of pathology.The expressions of MVD and VEGF were detected as well.All the indi-ces were compared between the two groups. Results(1)The differences between the lung cancer lymph node groups in the iodine concentration,normalized iodine concentration(NIC),spectrum curve of arterial phase,MVD and VEGF were statistically significant(P<0.05).(2)The iodine concentration,NIC and spectrum curve of arte-rial phase were positively correlated with MVD and VEGF.Conclusion Iodine concentration,NIC,and spectrum curve of arterial phase of DSCT dual energy imaging can be regarded as part of the important indices for preopera-tive diagnosis of lymph node metastasis of NSCLC.

OBJECTIVE To explore the difference in chemical components of essential oil from medicinal part （rhizome）and non-medicinal parts （fibrous roots ，stems，and leaves ）of Atractylodes chinensis，and to preliminarily evaluate their antibacterial activity in vitro . METHODS The essential oil was extracted from three parts of A. chinensis by steam distillation ，and their chemical components and relative contents were analyzed and identified by gas chromatography -mass spectrometry （GC-MS）. The antibacterial activities of essential oil （5 mg/mL） from different parts against Staphylococcus aureus ，S. albus and Bacillus subtilis were determined by paper diffusion method . The correlation between chemical components in essential oil and antibacterial activity was analyzed . RESULTS A total of 60 chemical constituents were identified from the essential oilof rhizome ，fibrous roots ，stems and leaves of A. chinensis， mainly composed of terpenes ，sesquiterpenoids，alcohols and ketones. There were 8 kinds of common components in the essential oil of rhizome ，fibrous root and stem and leaves ，which were elementol ，cadinene，agarospirol，valencian citrine ， caryophyllin，β-sesquidiene，γ-eucalyptol and β-eucalyptol. A total of 26 components were identified from the essential oil of rhizome，of which the relative content of 4-benzaldehyde was the highest （31.56%）；a total of 21 components were identified from the essential oil of fibrous roots ，among which the relative content of β-eucalyptol was the highest （44.39%）；a total of 42 components were identified from the essential oil of stems and leaves ，among which the relative content of β-sesquidiene was the highest（14.83%）. The essential oil from different parts had certain antibacterial effect on S. aureus，S. albus and B. subtilis. The order of antibacterial effect was rhizome ＞fibrous roots ＞stem and leaves ；the relative contents of β-caryophyllene，α-humulene and modhephene were positively correlated with inhibitory effects of essential oil against S. aureus and B. subtilis（P＜0.05 or P＜0.01）. The relative contents of atractylone ，zingiberene and agarospirol were positively correlated with the inhibitory effect of essential oil against B. subtilis（P＜0.05 or P＜0.01）. CONCLUSIONS There are significant differences in the chemical composition and contents of essential oil from medicinal and non -medicinal parts of A. chinensis，and all of them have antibacterial activity in vitro .