Oceanic carbon monoxide(CO) has been of biogeochemical interest due to its significant role in global carbon cycle and the greenhouse effect. A headspace method coupled with ta3000 trace gas analyzer system for the determination of CO in seawater was developed. The effects of temperature, equilibrium time and water/gas volume ratio on the sensitivity of headspace analysis were studied in detail. The results showed that CO concentrations in seawater were measured successfully by the 50-mL glass-only syringes with a water/gas volume ratio of 44∶ 6 and an equilibrium time of 5 min at 20 ℃ room temperature. Under the optimized conditions, the linear range of concentrations of CO was 0-2.7×10~(-6), r=0.999,p<0.0001. The relative standard deviation of the analysis method was <4.4%, with a detection limit of 0.02 nmol/L. The average recovery of CO was 90.5%. The concentrations of CO in surface waters of the North Yellow Sea were measured using this method and ranged from 0.20 nmol/L to 3.13 nmol/L, indicating that this method can be successfully applied to the detection of the in situ CO concentrations in seawater.

Gas chromatography with mass spectrum detector ( GC-MSD) coupled with purge-and-trap system was set up to analyze the concentration of isoprene in natural waters. The best experimental conditions were established, including purge gas flow rate ( 50 mL/min ) , purge time ( 15 min ) , the optimum capillary column ( Rt-Alumina BOND/KCl) and the appropriate condition of temperature programming. When analyzing isoprene in natural waters, the precision was <4% (n=6), the detection limit was 0. 5 pmol/L and the recovery was 91%-102%. The preservative experiment showed that there was no obvious variation in sample concentrations of isoprene within 60 days. The concentrations of isoprene measured with the method ranged from 60 . 8 to 278 . 7 pmol/L in the Jiaozhou Bay and its adjacent river estuaries and from 44 . 7 to 77 . 2 pmol/L in Yellow River estuary, which was in good accord with those results reported in literatures in other coastal waters. In conclusion, the analytical method could meet the requirements of the analysis of concentration of isoprene in natural waters.

AIM: To establish the quality standard for Hanshi Tougu Tablets(Radix Aconiti Praeparata,Radix Aconiti Kusnezoffii Praeparata,Ramulus Cinnamomi,Rhizoma Atractylodis, Semen Sinapis,Radix Aucklandiae,Radix Glycyrrhizae). METHODS: Rhizoma Atractylodis,Semen Sinapis,Radix Glycyrrhizae in Hanshi Tougu Tablet were identified by TLC.The content of cinnamaldehyde and costunolide in Hanshi Tougu Tablets were determinded by HPLC. RESULTS: Rhizoma Atractylodis,Semen Sinapis,Radix Glycyrrhizae,Radix Aconiti Praeparata and Radix Aconiti Kusnezoffii Praeparata could be identified by TLC.Cinnamaldehyde showed a good linear relationship at the range of 2.104 ?g?mL~(-1)-52.60 ?g?mL~(-1),r=0.999 8(n=5), and the recovery was(99.62%,) RSD was(0.88%).Costunolide also showed a good linear relationship at a range of(0.036) mg?mL~(-1)-0.54 mg?mL~(-1),r=(0.999 9)(n=5),and the recovery was 96.10%,RSD was 0.15%. CONCLUSION: The method is simple,accurate and with strong specificity and can be used for the quality control of Hanshi Tougu Tablets.

ObjectiveTo elucidate the clinical application value of intravascular ultrasound(IVUS) in assessing intermediate lesions and the relationship between serum levels of fractalkine,CD36 and LP-PLA2and severity of coronary artery atherosclerosis.MethodsOne hundred and twenty patients with unstable angina underwent coronary angiography.Then the patients were divided into two groups:severe lesion group (lumen diameter stenosis greater than 70％,including 40 patients),and the intermediate lesion group lumen diameter stenosis(50％～70％,80 patients).IVUS were performed in all patients to analysis the coronary lesions.Concentrations of CD36,fractalkine and LP-PLA2 were measured by means of ELISA.Results IVUS found that 74％ intermediate lesion patients had soft lipid plaques,while 48％ severe lesion patients had lipid plaques ( P＜0.01 ).Patients with severe lesion had larger plaque burden and vascular remodeling index than those of patients with intermediate lesions(P＜0.05～0.01).There were 59 patients(74％) in the intermediate lesion group underwent PCI.IVUS also found the PCI patients had larger plaque burden and vascular remodeling index.Concentration of CD36 was significantly higher in severe lesion group than that of intermediate lesion group (P＜0.05).ConclusionsIVUS could further clarify the characteristics of the intermediate and severe lesions,and provide guidance for PCI treatment.Plasma CD36 level could be used to predict pathological severity of coronary atherosclerosis.

Objective:To observe the application of case-based problem-based learning (PBL) teaching in the postgraduate education of radiography.Methods:A total of 48 postgraduates in the Batch 2019/2020 of professional masters majoring in radiography were selected as research objects, and they were divided into observation group ( n=24, Batch 2020) and control group ( n=24, Batch 2019). The students in the control group were taught by traditional teaching, and the students in the observation group were taught by case-based PBL teaching method. The differences in imaging diagnosis level and structured assessment scores of the two groups of students and their evaluation of the teaching process were analyzed. SPSS 20.0 was applied to perform the t test and chi-square test. Results:The imaging diagnosis ability of the students in the observation group (84.98±7.51) was significantly higher than that in the control group (78.21±6.96) , and the difference was statistically significant ( P<0.05). The students in the observation group had higher ability of imaging diagnosis skills and case analysis and diagnosis during the structured assessment ( P<0.05). The students in the observation group had higher overall satisfaction with the teaching process than those in the control group ( P<0.05). Conclusion:The case-based PBL teaching is of great help in improving the clinical thinking and imaging diagnosis ability of postgraduates majoring in radiography. In the application, it is necessary to continuously improve and supplement the teaching implementation plan according to the teaching evaluation and feedback.