Objective To explore the values of pixel indexes (PI) with multiple-slice spiral CT low-dose two-phase scanning for assessing the pulmonary function in chronic obstructive pulmonary disease (COPD).Methods Thirty-six patients with COPD (COPD group)and 30 healthy people (control group)underwent pulmonary function test (PFT).Chest 64-MSCT low-dose (50 mAs) scanning at full inspiration and expiration,routine scanning (100 mAs) at inspiration were performed.The effective dose (ED) was calculated.The lung was divided into three regions ( upper,middle,lower).PI of lung were divided into five groups:-960--1024, -910--960, -800--910, -700--800,-400--700.ThePI-910 (sum of the PI under -910 HU) of low-dose scanning at each region were measured and calculated using pulmo software. All PI included PIin-910,PIex-910,PIin-910-PIex-910, PIex-910/PIin-910 and (PIin-910-PIex-910)/PIin-910.All patients underwent PFT within 3 days after 64-MSCT canning,FEV1％ and FEV1/FVC were selected for comparison. Results The PIin in three regions ( - 960 - - 1024,-910 - -960,-800 - -910) were statistically significant between normal and COPD groups( U =0.00,57.00,20.50,P ＜ 0.01 ). The PIex in all regions were statistically significant ( U =0.00,0.00,71.52,191.00,6.00,P ＜ 0.01 ). PI-910--1024 at expiration and inspiration were correlated with FEV1％ and FEV1/FVC( r =- 0.548,- 0.664,- 0.752,- 0.781,P ＜ 0.01 ).PIin -910,PIex -910,PIex-910/PIin -910,( PIin -910-PIex -910 )/PIin -910 had a good correlation with FEV1％ and FEV1/FVC ( r =- 0.548,- 0.664,- 0.752,- 0.781,- 0.674,- 0.642,0.674,0.642,P ＜ 0.01 ).Conclusion Pixel indexes of 64-MSCT low-dose two-phase scanning can be used to evaluate pulmonary function in COPD patients.

The bioelectrical impedance measurement is a detection technique that uses the electrical characteristics and changes in human tissues and organs to detect biomedical information related to human physiological and pathological conditions. This article makes a comprehensive introduction from the aspects of impedance cardiography, electrical impedance respiratory monitoring, electrical impedance tomography, electrical impedance gastric dynamics detection technique, contact impedance and so on, as well as comprehensively introduces the progress and application status of bioelectrical impedance measurement methods.
Electric Impedance ; Humans ; Monitoring, Physiologic ; Tomography

This study describes the development of a wireless and wearable ECG monitoring system with ultra-low power consumption. The system is mainly composed of a connection part of an ECG electrode sticker, an electrocardiogram collecting part, a data storage part, a Bluetooth main control unit, a charging module, a voltage regulator and a lithium battery. The low-power ECG acquisition chip ADS1292R and the ultra-low-power Bluetooth microcontroller nRF51822 together constitute the ECG signal acquisition and wireless data communication part. The collected ECG signals can be sent to the mobile APP through the Bluetooth function provided by the MCU, and can completly display and analysis to achieve low power system. After testing, the system power consumption is only (3.7 V×2.87 mA)10.619 mW, and if it is optimized, it can further reduce power consumption, therefore, the system design can have good applicability.
Electric Power Supplies ; Electrocardiography ; Equipment Design ; Monitoring, Physiologic/instrumentation* ; Signal Processing, Computer-Assisted ; Wearable Electronic Devices ; Wireless Technology