OBJECTIVETo establish the method of detecting the concentrations of chlorpyrifos in air of workplace with high performance liquid chromatographic (HPLC).

METHODSAccording to standards of methods for determining the chemical substances in workplace air, chlorpyrifos in the air was collected by silicone tube, then dissolved by acetonitrile and determined by high performance liquid chromatography with UV-detector.

RESULTSThere was a linear relationship within the range of 0 ∼ 10.0 µg/ml, and regression equation was y = 5206.1x - 104.7, correlation coefficient was 0.9999, the detection limit was 0.006 µg/ml. The lowest detected concentration was 0.001 mg/m(3) (sampling volume 4.5 L). The average recoveries was 98.3% ∼ 102.5%. The within-run precision was 1.96% ∼ 4.39%, the between-run precision was 2.76% ∼ 5.87%. The desorption efficiencies were 99.0% ∼ 103.3% and the sampling efficiencies were 94%. The samples in silicone tube could be stored for 15 days at room temperature.

CONCLUSIONThe present method could meet with the requirements of Guide for establishing occupational health standards-Part 4 Determination methods of air chemicals in workplace and be feasible for determination of chlorpyrifos in workplace air.

Air Pollutants, Occupational ; analysis ; Chlorpyrifos ; analysis ; toxicity ; Chromatography, High Pressure Liquid ; methods ; Limit of Detection ; Reproducibility of Results ; Workplace

OBJECTIVETo establish a method for determination of chloropicrin in the air of workplace by gas chromatography with liquid absorption collection.

METHODSChloropicrin in sample air was collected by absolute ethyl alcohol in a porous glass plate absorption tube. Following direct sample loading, samples were separated by gas chromatography and detected with a micro-electron capture detector. The present method was compared with the national standard method.

RESULTSThe range of linearity was 0-3.0 µg/ml, and the regression equation was y = 3488.80x-57.84, with a correlation coefficient of 0.999 4. The detection limit was 0.003 µg/ml, with a minimum detectable concentration of 0.005 mg/m³ based on a 3.0 L sampling volume. The average recovery rate was 98.9%∼103.2%. The within-run precision was 0.96%-2.12%, and the between-run precision was 2.75%-4.59%. The sampling efficiency was 98.6%. Samples in porous glass plate absorption tube could be stored at 4 °C for at least 5 days. The result ratio of this method to the national standard method was 97.7%-108.0% .

CONCLUSIONThe present method meets the requirements of "Guide for establishing occupational health standards-Part 4: Determination methods of air chemicals in workplace" (GBZ/T 210.4-2008), and is feasible for determination of chloropicrin in the air of workplace.

Air ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography, Gas ; methods ; Hydrocarbons, Chlorinated ; analysis ; Workplace

OBJECTIVETo study whether human neural progenitor cells can differentiate into neural cells in vivo and improve the recovery of injured spinal cord in rats.

METHODSHuman neural progenitor cells were transplanted into the injured spinal cord and the functional recovery of the rats with spinal cord contusion injury was evaluated with Basso-Beattie-Bresnahan (BBB) locomotor scale and motor evoked potentials. Additionally, the differentiation of human neural progenitor cells was shown by immunocytochemistry.

RESULTSHuman neural progenitor cells developed into functional cells in the injured spinal cord and improved the recovery of injured spinal cord in both locomotor scores and electrophysiological parameters in rats.

CONCLUSIONSHuman neural progenitor cells can treat injured spinal cord, which may provide a new cell source for research of clinical application.

Objective:To explore the diagnostic value of magnetic resonance(MR)high-resolution imaging of vascular wall on vertebrobasilar artery tortuosity prolongation complicated by multiple cerebral infarction in posterior circulation.Methods:Regression analysis was used in this research.A total of 138 patients with vertebrobasilar artery tortuosity prolongation who admitted to Hengshui City People′s Hospital from January 2020 to January 2023 were selected.Among of them,54 patients who complicated with multiple cerebral infarction in posterior circulation were divided into the occurrence group,and 84 patients without multiple cerebral infarction in posterior circulation were divided into the non-occurrence group.All patients underwent high-resolution MR imaging of vascular wall,and the basilar artery(BA),hemodynamic indicators such as systolic peak(Vs),average peak(Vd),diastolic peak flow velocity(Vm),pulsatile index(PI),blood flow resistance index(RI),as well as intracranial responsibility plaque characteristics and vertebral basilar artery grading between two groups were compared.Results:The Vs,Vd,Vm,PI and RI indicators of patients in the non-occurrence group were significantly higher than those in the occurrence group,and the differences were statistically significant(t=11.742,4.323,7.367,4.824,2.351,P<0.05),respectively.The degree(60.31±4.24)%of intracranial plaque stenosis in the non-occurrence group was significantly lower than(73.67±5.96)%in the occurrence group,and the difference was statistically significant(t=15.376,P<0.05).There were no statistically significant differences in plaque area,plaque load,arterial remodeling index and eccentricity index between the two groups(P>0.05).The height level of vertebral basilar artery bifurcation and the degree of vertebral basilar artery deviation in the non-occurrence group were significantly lower than those in the occurrence group,with statistically significant differences(x2=3.907,6.419,P<0.05).Conclusion:MR high-resolution imaging of vascular wall can clearly display the blood flow velocity and intracranial plaque situation in patients with vertebrobasilar artery tortuosity prolongation,and conduct the grade for the vertebrobasilar artery,which has significant application value in predicting the occurrence of vertebrobasilar artery tortuosity prolongation complicated by multiple cerebral infarction in posterior circulation.

Clinically， the occurrence of the breaking bad news is inevitable. For patients， they not only need to accept and cope with bad news， but also need to inform the bad news to their families with clear thinking and appropriate language， seeking their support and cooperation. This paper analysed the connotation and informing dilemma of bad news， investigated patients’ informing tendencies， as well as evaluated the advantages and disadvantages of three disclosure methods， including concealment， immediate informing， and staged informing. On these bases， a detailed response strategy for patients to inform their families was proposed in three parts， including pre-preparation， mid-articulation， and post-summary. In the initial phase， thorough preparation is essential. During the middle stage， when delivering bad news， use plain language and help family members adjust their emotions. In the final phase， ensure that all information and viewpoints have been fully communicated. In addition， the roles and analysis steps that doctors should play were analysed from their perspective and combined with the degree of doctor-patient trust. Effective informing of bad news is not only about communication skills， but also involves a deep understanding and respect for the psychological needs of patients and their families. Through meticulous preparation， appropriate expression， emotional support， and clear confirmation， communication and trust are promoted to face and overcome difficulties together.

【Objective】 To evaluate the association between prophylactic plasma transfusion and postoperative bleeding rate in critically ill patients undergoing different invasive procedures. 【Methods】 The information of ICU patients who received different invasive procedures from January 2019 to December 2019 in 6 tertiary hospitals in China were retrospectively investigated. The inclusion criteria of patients were as follows: age ≥ 18 years; received invasive procedures; INR ≥ 1.5 within 72 hours before surgery. Exclusion criteria were patients with incomplete case records. The patients finally included in the study were divided into prophylactic plasma transfusion group and non-prophylactic plasma transfusion group according to their plasma transfusion status. The outcome variable was the incidence of invasive procedure-related bleeding within 48 hours after different invasive procedures. 【Results】 A total of 407 patients underwent invasive procedures, and 362 patients were finally included in this study after excluding 45 patients with incomplete case records. The proportions of prophylactic plasma transfusion in different types of invasive procedures were central venous catheterization (46/146, 31.5%), thoracentesis (13/37, 35.1%), bronchoscopy (8/31, 25.8%), tracheal intubation (9/38, 23.7%), arterial catheterization (9/50, 18.0%) and others (13/60, 21.7%). The bleeding rates showed that different invasive procedures presented no statistical difference between the groups received plasma transfusion or not. In the prophylactic plasma transfusion group, the bleeding rate of arterial catheterization (4/9, 44.4%) was the highest, but all were potential bleeding, followed by tracheal intubation (4/10, 40.0%) and central venous intubation (16/46, 34.8%), with a higher rate of significant bleeding. 【Conclusion】 Prophylactic infusion of plasma did not reduce the bleeding rate after different invasive procedures, but prospective studies are needed to further confirm the conclusion; this study also provides a certain data basis for later prospective studies.