Firstly,this article analyzes the requirement of the standard voltage for the ECG & EEG verification instrument.Then it analyzes the feasibility of measurement using 34401A multimeter and provides the test method.This method is proved to be exact and reliable by experiment.

The digital EEG instrument is the use of that the electrical activity of cerebral cortex are extracted and recorded by electrodes, which diagnose and treat the human brain and nervous system. The examination methods that is strong interoperability is introduced based on JJG 954 -2000 Digital Electroencephalogram Mapping & Brain Electric Activity Mapping and combined with practical work experience for years.

Objective To determine the purity of sodium nitrite(NaNO2) using in stray light standard substance which was applied to check semiautomatic clinical chemistry analyzer.Methods Titration was used to determine the purity of NaNO2,the uncertainty of the purity was assessed,and a parallel test was used to validate the uncertainty.Results The purity of NaNO2 was 99.81%,and its uncertainty was 0.86%.Conclusion The uncertainty of the purity passes the validation,it shows that the purity test is credible,and its uncertainty assessment is logical.

Objective To investigate the effects of sufentanil,remifentanil and fentanyl oH cellular immune function in patients undergoing radical resection of esophageal cancer.Methods Forty-five ASA Ⅰ or Ⅱpatients aged 45-64 yr undergoing radical resection of esophageal cancer were randomly divided into 3 groups(n=15 each):sufentanil group(SF);remifentanil group(RF)and fentanyl group(F).The patients were premedicated with iv atropine 0.5 mg.Anesthesia was induced with midazolam 0.04 mg/kg,propofol TCI(CT=3μg/ml)and TCI of sufentanil,remifentanil or fentanyl(CT=0.5,5 and 5 ng,ml respectively in the 3 groups).Endobronchial intubation was facilitated with vecuronium 0.1 mg/kg.The patients were mechanically ventilated.PETCO2 was maintained at 30-40 mm Hg.Anesthesia was maintained with inhalation of sevoflurane(0.7-1.5 MAC)and TCI of sufentanil,remifentanil or fentanyl(CT=0.5,5 and 5 ng/ml respectively).Venous blood samples were taken from peripheral vein before anesthesia(T0,baseline),60 min after skin incision(T1),immediately(T2),24 h(T3)and 72 h(T4)after the end of operation for determination of the expression of CD3+,CIM+,CD8+on T cells and CD3-CD16+CD56+on natural killer cells by flow cytometry,CD4+/CD8+ratio,serum concentrations of IL-2 and IL-10 by ELISA.Results Compared with the baseline values,the CD4+T-lymphocytes and CIM+/CD8+ratio were significantly decreased at T2,while the CD3-CD16+CD56+NK cells were significantly increased in all 3 groups.The CD3+T-lymphocytes were significantly decreased at T2 as compared to the baseline value at T0 in SF and RF groups.The CIM+and CD3+T-lymphocytes were significantly decreased at T3 as compared with the baseline value in all 3 groups.Serum IL-2 concentration was significantly higher at T3 in SF group than in RF group.Serum IL-10 concentration was sismficantly higher at T4 in RF group than in SF group.Conclusion Sufentanil,remifentanil and fentanyl can depress cenular immune function to some extent in patients undergoing radical resection of esophageal cancer.

To develop a standard defibrillation energy source which can output monophasic and biphasic de-fibrillation impulses and can display standard energy values. The storage capacitor was charged by single-end flyback transformator and discharged through the H bridge composed of insulated gate bipolar transistor (IGBT). Impulse voltage and current were collected by divider while discharging, and the energy value was calculated by STM32. The en-ergy value and waveform were displayed through the control module. The energy source could output both monophsic and biphasic waveforms, and the accuracy of displayed value was higher than ±2% or ±1 J. The standard defibrillation energy source can be used as standard device for defibrillator analyzer, and the metrological trace-ability system of defibrillation energy may come to be completed.