Objective To establish a method for the simple and rapid extraction and detection of nitrosodipropulamine(NDPA).Methods NDPA at levels of?g /L grade in chemical industrial wastewater was enriched efficiently using the purge and trap(P&T)method with a Trap3tube under the standard program,including the flow rate of purge gas(40ml/min),the time of purge(11min),the temperature of desorb(225℃),the time of desorb(4min),the temperature of bake(230℃)and the time of bake(10min).The NDPA concentrations were determined by gas chromatography-mass spectroscopy(GC-MS )and chemical ionization(CI )and select ion mode(uSIS)coupled with the purge and trap(P&T)(P&T/GC-MS/CI /uSIS)method Results The detection limit,recovery rates and relative standard deviation(RSD)of the method were3?g /L,62.60%-96.31%and7.5%respectively.The linearity of method was good in the5-30?g /L range with the correlation coefficient 0.978.Conclusion The P&T/GC-MS/CI /uSIS method could be used to detect semi-volatile NDPA in chemical industrial wastewater.

Objective To explore the preparation and quality control of As2 O3 nanoparticle .Methods PEG‐PLA was used as the vector material to prepare As2 O3 nanoparticle with ultrasonic emulsification method ,and the VEGFR‐2 was coupled to obtain VEGFR‐2/As2 O3‐PEG‐PLA nanoparticle .The particle size distribution ,Zata potential ,loading efficiency (LE) ,encapsulation effi‐ciency(EE) ,drug release in vitro and stability was determined ,and morphological characteristics was observed by transmission elec‐tron microscope(TEM) .Tweety‐four hepatocellular carcinoma nude mices were randomly divided into VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group and As2 O3‐PEG‐PLA nanoparticles group ,by tail vein injection of nanoparticles .High performance liquid chro‐matography was used to determine content of As2 O3 .After 21 d ,six nude mices in each group were killed ,and the immunohisto‐chemistry and western blot method was used to detect the expression of VEGFR‐2 .Results The particle size of VEGFR‐2/As2 O3‐PEG‐PLA was determined to be (141 .9 ± 13 .2)nm ,Zata potential was (10 .2 ± 1 .1)mV .It was found to spherical or oval shape , with uniform size and dispersibility under TEM .LE and EE was (5 .51 ± 1 .83)% and (62 .12 ± 5 .98)% ,respectively .Drug release in vitro showed that VEGFR‐2/As2 O3‐PEG‐PLA exhibited controlled release effect ,with half of the release time as 10 h .Besides , VEGFR‐2/As2 O3‐PEG‐PLA showed a good stability in 3 days .Compared with As2 O3‐PEG‐PLA nanoparticles group ,the concen‐tration of As2 O3 in tumor and liver tissue was high ,the concentration of As2 O3 in blood ,heart ,kidney tissue was low ,the expression of VEGFR‐2 in tumor tissue was low in VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group(P< 0 .05) .Conclusion The prepared As2 O3 nanoparticle using PEG‐PLA as vector and VEGFR‐2 as target showed uniform size ,high EE and LE ,good stability .And it preliminarily proved that VEGFR‐2 could be targeted in nude mice .

Objective To investigate the clinical efficacy of laparoscopic spleen-preserving distal pancreatectomy (Kimura method and Warshaw method) for benign lesions of pancreatic body and tail.Methods The retrospective cohort study was conducted.The clinicopathological data of 39 patients with benign lesions of pancreatic body and tail who underwent laparoscopic spleen-preserving distal pancreatectomy in the Second Affiliated Hospital of Nanchang University between March 2008 and January 2018 were collected.Of 39 patients,28 undergoing Kimura method (splenic artery and vein-preserving distal pancreatectomy) were allocated into the Kimura group,and 11 undergoing Warshaw method (cutting splenic vessels and preserving short gastric vessels)due to serious adhesion between pancreatic body and tail and splenic hilum were allocated into the Warshaw group.Observation indicators:(1) operation situations;(2) postoperative situations;(3) follow-up situations.Followup using outpatient examination and telephone interview was performed to detect blood glucose level and tumor recurrence of patients up to March 2018.Measurement data with normal distribution were represented as (x)±s and comparison between groups was analyzed using the t test.Measurement data with skewed distribution were described as M (range) and comparison between groups was done using nonparametric rank-sum test.Comparisons of count data were analyzed using chi-square test or Fisher exact probability.Results (1) Operation situations:39 patients received laparoscopic spleen-preserving distal pancreatectomy,operation time and volume of intraoperative blood loss of 39 patients were respectively (194 ±58)minutes and 100 mL (range,30-800 mL).The operation time and volume of intraoperative blood loss were respectively (197±56)minutes,100 mL (range,30-800 mL) in the Kimura group and (186±63)minutes,150 mL (range,30-450 mL) in the Warshaw group,with no statistically significant difference between groups (t =0.494,Z =-0.597,P＞ 0.05).(2) Postoperative situations:time to anal exsufflation and duration of hospital stay were respectively (2.6±0.8)days,(9.2±7.3)days in 39 patients and (2.4±0.6)days,(7.5±4.2)days in the Kimura group and (2.8±1.3)days,(13.5±11.1)days in the Warshaw group,with no statistically significant difference between groups (t=-0.720,-1.736,P＞0.05).Seven patients had postoperative complications.The incidence of complication was 2/28 in the Kimura group,1 patient with pancreatic leakage at 5 days postoperatively was cured by 15-day B ultrasound guided catheter drainage,and 1 who was diagnosed as pulmonary infection by chest CT examination at 5 days postoperatively was discharged from hospital after 8-day anti-infection and sputum-inductive treatments.The incidence of complication was 5/11 in the Warshaw group,3 patients with sustained fever at 5 and 7 days postoperatively who were diagnosed as grade 1 splenic infarction by epigastric enhanced CT examination were improved and discharged from hospital by antibiotic and low molecular weight heparin treatments,and then epigastric enhanced CT re-examination at 3 months postoperatively showed recovery of splenic perfusion;1 with pancreatic leakage at 7 days postoperatively was cured by 18-day conservative treatment;1 who was diagnosed as delayed gastric emptying by upper gastrointestinal contrast at 16 days postoperatively was improved and then discharged from hospital by 15-day placement of intestinal feeding tube and nutrition support therapy.There were statistically significant differences in the incidences of overall complication and splenic infarction between groups (x2 =5.485,4.878,P＜0.05) and no statistically significant difference in the incidence of other complications between groups (P＞0.05).(3) Follow-up situations:39 patients were followed up for 12 months (range,2-64 months).During the follow-up,six patients had normal blood glucose level,and all patients had good quality of life,without recurrence.Conclusions Laparoscopic spleen-preserving distal pancreatectomy for the benign lesions of pancreatic body and tail is satisfactory in short-and long-term curative effects.The incidences of complication and splenic infarction of Kimura method are lower than that of Warshaw method.