Objective To evaluate the ability of contrast-enhanced ultrasound (CEUS) as a prognostic indicator of renal function in chronic kidney disease (CKD) patients.Methods A total of 122 patients with CKD were collected,and patients with allergies to sulfur hexafluoride,pregnancy,cardiopulmonary insufficiency,urinary calculus and tumour were excluded.These patients were divided into estimated glomerular filtration rate [eGFR,ml·min1· (1.73 m2)-1] ≥60 group,eGFR 30-59 group and eGFR ＜ 30 group.CEUS was performed after an intravenous bolus injection of 1.5 ml SonoVue (BR1;Bracco Milan,Italy).Time-intensity curves (TICs) and quantitative indexes were created using QLAB quantification software.Followed up for 2 years,and patients with eGFR dropped 50％,double serum creatinine and end-stage renal disease (ESRD) were regarded as having kidney failure events.Risk factors related to kidney survival were investigated using a multivariate Cox regression model.Results One hundred patients were enrolled in the study,with 78％ patients in CKD 1-2 stages,16％ in CKD 3 stage and 6％ in CKD 4-5 stages.Patients were followed for a mean period of 14.1 months,ten (10％) patients exhibited composite kidney failure events.Among 3 groups,significant differences in the left kidney length derived peak intensity (DPI) were noted (P=0.014,P=0.010).Multivariate Cox regression analysis revealed that the DPI was an independent factor of progression of kidney disease.Multiple linear regression showed that age,basic eGFR,peak intensity were associated with eGFR decline rate.Patients with DPI ＜ 12.27 db were less to recover from kidney disease progression as compared with patients with DPI≥ 12.27 db (P=0.008).The area under the curve (AUC) for DPI was 0.778(95％ CI 0.612-0.944,P＜ 0.05),with a sensitivity of 64％ and a specificity of 88％.Conclusions The DPI might be the most valuable CEUS parameter for the evaluation of renal function.The DPI could serve as an independent predictor of the long-term prognosis of CKD patients.

ObjectiveTo explore the application effect of outcome-based education model in clinical teaching for neurosurgery nursing students. MethodsBy convenience sampling, the nursing students on placement rotation in Department of Neurosurgery in Nanfang Hospital of Southern Medical University from August 2016 to July 2017 were selected and assigned into the control group (n=55), and those from August 2017 to July 2018 were put into the observation group (n=51). According to the requirements of the curriculum, the traditional teaching method was adopted for the control group, on the basis of that, the outcome-based education model was adopted for the observation group. The two groups of nursing students rotated in the Department of Neurosurgery for four weeks. Two independent sample t-test was used to compare the score of theoretical achievement, clinical achievement, Clinical Communication Ability Scale and Problem-solving Ability Scale between the two groups. ResultsThe average theoretical and operational scores of nursing students in the control group were (91.71±3.28) and (89.38±5.39) respectively. The average theoretical and operational scores of nursing students in the observation group were (94.06±2.73) and (91.71±4.67), respectively. There were significantly statistical differences between the two groups (P＜0.05). The total score of Clinical Communication Ability Scale of nursing students in the observation group was (90.08±7.43), higher than that of the control group (83.38 ±7.07), there were significantly statistical differences between the two groups (P＜ 0.01);the scores of Problem-solving Ability Scale of nursing students in the observation group were higher than that of the control group (P＜ 0.01), there was significantly statistical difference between the two groups. ConclusionsThe outcome-based education model in clinical teaching for neurosurgery nursing students can effectively improve the nursing students' theoretical and operational performance, enhance their clinical communication skills and problem-solving ability and is conducive to cultivating excellent practical talents in clinical practice.

Objective To explore the application of Plan-Do-Check-Act(PDCA)cycle management to continuously im-prove the service quality of outpatient pharmacy and enhance patient satisfaction.Methods To address the problem of long wait-ing time for patients in outpatient pharmacy,we applied PDCA cycle to investigate the factors affecting patients'waiting time in the process of medicine collection,analyze the current situation,determine the expected goals,formulate the service quality im-provement plan of outpatient pharmacy,implement the improvement plan,follow up and supervise,and summarize and analyse the problems regularly until it was solved.Results After implementing the PDCA cycle in the management,the service quality of outpatient pharmacy was improved,the waiting time was significantly shortened and the satisfaction of medical treatment was in-creased.Conclusion The application of PDCA cycle method is effective in improving the service quality of outpatient pharmacy.Therefore,it is recommended for broader implementation.

Background With the events reporting on odors in drinking water, odorous substances in water have become a hot topic in water quality analysis. Due to the low concentration of the odor threshold and the complexity of the odor components in water, it is difficult to make accurate qualitative and quantitative analysis. So it is necessary to develop a highly sensitive and accurate qualitative and quantitative analysis method. Objective To establish a method for simultaneous determination of four odorous substances, including dimethyl disulfide, dimethyl trisulfide, 2-methylisoborneol, and geosmin in water by purge and trap-gas chromatography-tandem mass spectrometry. Methods A certain amount of water sample was stored in the sample vial of a purge and trapinstrument. Through nitrogen purging, the odorous substances in water were purged out and enriched in the trap. Subsequently, the odorous substances were rapidly released at high temperatures after heating the trap, and then carried by carrier gas into gas chromatograph. After temperature programming, the substances were separated by an Agilent DB-624 capillary chromatographic column (30 m×0.25 mm, 1.4 μm) and determined by tandem mass spectrometry in multiple reaction monitoring modes, with internal standard method for quantification. The current project optimized purge time, sodium chloride concentration in water sample, desorption temperature, desorption time, and split ratio during the experimental process. Under the optimized experimental conditions, the standard curve, detection limit, and quantification limit were validated. Recovery tests with spiking concentrations of 5.0, 10.0, 30.0, 80.0 ng·L⁻¹ and precision tests were conducted on water samples. Finally, the established method was applied to detect odorous substances in source water, finished water, and pipeline water in Deqing County of Huzhou City. Result After the optimization, the purge time was 20 min, the desorption temperature was 280 ℃, the desorption time was 2 min, the split ratio was 10∶1, and no sodium chloride was added during the purge process. Under the optimized experimental conditions, the calibration curves for the four odorous substances showed an excellent linearity in the range of 1 to 100 ng·L⁻¹ (R>0.999), with 0.3 ng·L⁻¹ limit of detection and 1.0 ng·L⁻¹ limit of quantitation. The average recoveries were from 85.5% to 102.4% and relative standard deviations (RSD) from 1.6% to 5.2%. After applying this method to detect local source water, finished water, and pipeline water, it was found that the positive rates of 2-methylisoborneo, and geosmin were relatively high, while the positive rates of dimethyl disulfide and dimethyl trisulfide were relatively low. Only one sample of source water tested positive for dimethyl disulfide, and all samples were negative for dimethyl trisulfide. Conclusion Combined with the superiority of purge and trap and tandem mass spectrometry, the method has the advantages of easy to perform, strong anti-interference ability, good accuracy and precision, which meet the limit requirements of the four odorous substances in the expanded indices and reference indices of Hygienic standards for drinking water (GB 5749-2022). It also provides technical support for water quality assessment and analysis of odorous substances.