Aim:To develop a practical chiral CE method for the quantitative determination of the unwanted enantiomer[( R )-enantiomer]presented in zolmitriptan. Methods:The background electrolyte was 20 mmol/L sodium dihydrogenphosphate solution with 1% S-β-CD,adjusted to pH 3.50 with phosphoric acid. A fused-silica capillary(60 cm×50 μm ID,effective length 51.5 cm)was used at 20 ℃ for the separation. The applied voltage was -30 kV. The samples were loaded by hydrodynamic injection(50 mbar pressure,6 s). UV was measured at 220 nm. Results:Zolmitriptan and its chiral impurity were baseline resolved ( R s=6.66). The linearity was good over the concentration range from 4 to 80 μg/mL( r =0.999 8) of ( R )-enantiomer. The injection precision (expressed as CV%) was 2.83%. The average recovery was 99.97%( n =9). The limit of detection was 1.5 μg/mL. The host-guest complex binding constants were 964 and 905 mol-1 for ( R )-enantiomer and zolmitriptan,respectively. Conclusion:The method is suitable for the determination of ( R )-enantiomer in zolmitriptan and binding constants of zolmitriptan enantiomers to S-β-CD.

@@

Objective To reduce the radiation dose to children from CT scanning through proper adjustment to milliamps (mAs) and scan lengths with a view to learning the relationship between scanning condition and radiation dose.Methods To compare the differences in main scanning parameters used for head,chest and abdomen at multi-detector CT examination of paediatric patients (＜ 1 year old,1-5 years old,6-10 years old,11-15 years old) at seven hospitals in Jiangsu province.CT dose index (CTDI) and dose-length-product (DLP) were gained by using standard children dose model (diameter 16 cm) under the same scanning conditions.Effective doses (E) at different parts of the body from children CT scanning were estimated after modification by empirical weighting factor.Statistical analyses of mAs,scan lengths and DLP were performed with SPSS 16.0 software.The differences in radiation dose due to the choice of condition of scanning were compared between two typical hospitals.Results The mean values of effective doses to paediatric patients during head,chest and abdomen CT scanning were 2.46,5.69,11.86 mSv,respectively.DLP was correlated positively with mAs and scan length (head,chest and abdomen examination,r =0.81,0.81,0.92,P ＜0.05).Due to higher mAs used,the effective dose from chest and abdomen CT examination among all age groups was higher than that in Germany Galanski research.Due to larger scanning length in abdominal examination among all age groups,effective doses in hospital were the highest.Conclusions Reasonablely reducing the scan length and mAs during CT scanning could lower children's CT radiation risk,while clinical diagnosis is not affected.

Objective To verify the methodology for auditing dosimetric parameters in reference and non-reference conditions with thermoluminescent dosimeters (TLDs).Methods Under reference and non-reference conditions,the established TLD methods were used to observe the absorbed dose variations with depth,SSD,field size and 45 wedges for 10 photon beams at 5 hospitals.Dosimetric parameters,including doses at Dmax points in axis,on 5 electron beams of 9 MeV were measured.The measurement results were compared between the TLDs and plane parallel ionization chambers.Results For 6 MV photon beams,the relative deviation of between finger ionization chamber method and TLD chips was in the range of-1.7％ to 5.4％ under on-axis non-reference conditions,and-6.3％ to-0.6％ under off-axis non-reference conditions,respectively,all within the range of ≤ ± 7％ as required by the IAEA.The relative deviation between plane parallel chamber and TLD method was-2.3％ to 3.7％,within ± 5％ as required by the IAEA.Conclusions It is convenient and feasible to use TLD method for quality audits of dosimetric parameters in radiotherapy.

Objective To evaluate the difference of clinical short-term effect and adverse reaction between paclitaxel liposome and paclitaxel in non-small cell lung cancer patients with lymph node metastasis after pulmonary resection.Methods Sixty-eight patients after pulmonary resection were divided into two groups by random digits table method,37 patients in experimental group with paclitaxel liposome (135mg/m2) combined with carboplatin (CBP) at 300 mg/m2 in chemotherapy,and 31 patients in control group with paclitaxel (135 mg/m2) combined with CBP at 300 mg/m2 in chemotherapy.Results All patients were evaluable.In experimental group,5 patients had complete remission,10 patients had partial remission,17patients were stable,5 patients' condition aggravated,the total effective rate was 40.5％(15/37),clinical control rate was 86.5％ (32/37).In control group,2 patients had complete remission,8 patients had partial remission,15 patients were stable,6 patients' condition aggravated,the total effective rote was 32.3％(10/31),clinical control rate was 80.6％(25/31).The treatment effectiveness in experimental group was significantly higher than that in control group (P ＜ 0.05).The main adverse reaction included marrow suppression,hair loss,muscle and joint pain and gastrointestinal symptom,there was no serious hypersensitivity.The rate of hypotension,face flushing,paresthesia,muscle and joint pain,erythra in experimental group was lower than that in control group [0 vs.9.7％ (3/31),5.4％ (2/37) vs.19.4％ (6/31),10.8％ (4/37) vs.22.6％ (7/31),13.5％ (5/37) vs.38.7％ (12/31),5.4％ (2/37) vs.25.8％ (8/31)] (P ＜0.0 1 or ＜0.05).Conclusion The curative effect rate of paclitaxel liposome is better than paclitaxel in patients with lymph node metastasis after pulmonary resection and with lower incidence of side effects.

Objective To measure the accuracy of multi-leaves collimator (MLC) leaves positions in intensity modulated radiation therapy (IMRT) for verification purpose.Methods Solid water homogeneous phantom with size of 30 cm× 30 cm was scanned by CT scanner.The scanned images were delivered to radiation therapy plan system (TPS) to formulate the therapy plan.The MLC leaves created 5 strips of exposure field,each 3 cm long and 0.6 cm wide.The strip-to-strip distance was 3 cm.With 6 MV X-rays,the SSD was 100 cm at the maximum dose point.The MU per strip was 250 MU.EBT2 radiochromic films each of 25 cm×25 cm were placed on the 30 cm×30 cm homogeneous solid phantom and covered with 1 cm thick solid phantom slabs for delivering of IMRT.Results For 7 of 8 accelerators,the differences of film-measured and TPS-planned MLC leaf position for every fence field were within ± 0.5 mm as required by IAEA,with only other one being-0.6 mm,not consistent with the IAEA requirements.The film-measured position difference between each pair and all pairs of leaves for 8 accelerators were all in line with IAEA's requirements.The film-measured actual width difference between each pair and all pairs of leaves was within ±0.75 mm as required by IAEA for 4 accelerators and outside ±0.75 mm for the other three,not consistent with the IAEA requirements.The standard deviation of film-measured actual width between each pair and all pairs of leaves for 6 accelerators were ≤ 0.3 mm,as required by IAEA,whereas ＞0.3 mm for the other two,not consistent with IAEA requirements.Conclusions The film dosimetric verification of IMRT is an important part of its quality assurance,featuring simple,reliable and highly accurate positioning and can meet measurement requirement.

Objective To explore the dosimetric verification method for absorbed dose and twodimensional dose distribution generated through multi-leaf collimator in radiotherapy.Methods A total of 8 medical accelerators were selected in Jiangsu province.Under 6 MV X-rays with a 5 cm × 5 cm field,the thermoluminescent dosimeter (TLD) and EBT3 radiochromic film (RCF) were used to audit the values calculated by treatment planning system (TPS).RCF was used to verify two-dimensional dose distribution under the 6 MV MLC beams for intensity modulated radiation therapy (IMRT).Results The relative dose deviation was from-1.4％ to 6.8％ for TLD and from-1.8％ to 7.8％ for RCF,with 7 accelerators meeting with the IAEA deviation requirement of ± 5％.The passing rates of two-dimensional dose distribution were between 73.7％ and 97.0％,with 7 accelerators greater than 90％.Conclusions TLD and RCF are feasible and suitable for large-scale verification of IMRT TPS absorbed dose and twodimensional dose distribution.

Objective: To evaluate the efficacy of covered stent (CS) in the treatment of central venous occlusive disease (CVOD) of different branches in hemodialysis patients. Methods: Twenty-five cases of CVOD in the First Affiliated Hospital of Sun Yat-sen University from Oct 2015 to June 2018 were enrolled. All patients underwent percutaneous transluminal angioplasty (PTA)+stent graft (PTS) successfully. The stent grafts of different diameters were implanted according to intraoperative angiography to measure the diameter of normal blood vessels around the diseased vessels. The operation was successful and the follow-up data was complete. According to the different branches of central venous lesions, the patients were divided into three groups: subclavian vein group, brachiocephalic vein group and superior vena cava group. The stent diameter, primary patency and assisted primary patency time were analyzed and compared in the three groups. Results: The diameters of the subclavian vein group, the brachiocephalic vein group, and the superior vena cava group were (10.29±0.42) mm, (12.29±0.32) mm and 13.00 mm, respectively. There were significant differences in the diameters of the subclavian vein group, the superior vena cava group and the brachiocephalic vein group (both P<0.05). As of the end of follow-up, the primary patency time of the subclavian vein group, the brachiocephalic vein group, and the superior vena cava group was (10.57±2.00) months, (19.40±3.28) months, and (32.75±3.28) months respectively. The primary patency time of the superior vena cava group was significantly longer than the other two groups (P<0.05). There was no significant difference in the primary patency time between the subclavian vein group and the brachiocephalic vein group (P=0.072). The assisted primary patency time of the subclavian vein group, the brachiocephalic vein group and the superior vena cava group was (15.57±3.20) months, (25.14±2.39) months, (39.00±3.03) months. There was a statistically significant difference in the assisted primary patency time between the three groups (P<0.05). Conclusions There are differences in vascular patency between postoperative vascular grafts of different diameters in different sites. The larger the diameter of the lumen stent, the longer the stent patency time is. It is important to protect the blood vessels with smaller diameters.

X-ray imaging is an important method for the diagnosis of corona virus disease(COVID-19), but there is a risk of nosocomial infection during X-ray imaging diagnosis. By analyzing the process of X-ray imaging diagnosis and the possible infection factors in hospital, Jiangsu province took the lead in issuing the Guideline for the nosocomial infection prevention and control of X-ray imaging diagnosis of COVID-19. This guideline clarifies the basic requirements for controlling infections during X-ray imaging diagnosis, the specific measures for staff protection, disinfection of personnel and places, and the protection and disinfection of subjects, which is instructive for field work. It is worth noting that while focusing on controlling infections, the principle of optimal protection for medical exposure cannot be ignored.