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Objective To study the method of gray-scale blood flow imaging and image processing in condition of high frequency ultrasound,and the implementation of the system.Methods On the base of research of scattered signals of red blood cells in high frequency ultrasound,20 MHz ultrasound mechanical and linear scanning probe was used to transmit a number of pulses on a scan line.Pulse-echo subtraction method was used to obtain the blood flow information.At the end,simulated blood vascular was used to conduct flow imaging,and the obtained images were analyzed.Results Experiment results showed that clear blood flow images were obtained using this system.The noise from perivascular tissue could be filtered and the signals from blood flow could be enhanced after image processing.Conclusions In the detection of superficial blood vessel,blood flow signals can be obtained even using single pulse emitting via high frequency ultrasound.The blood flow imaging system can be implemented after image processing.
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Objective To investigate the relationship between the parameters of the red blood cells and the corresponding param‐eters of mature red blood cells .Methods Blood samples of 112 healthy males and 110 healthy females were tested for these reticu‐locyte parameters by using Siemens Advia2120 hematology analyzer .Reference intervals were established .Comparisons between these reticulocyte parameters and the corresponding parameters of mature erythrocytes were drawn .Results Reference intervals for the healthy group recruited in this study were determined as follows .Females ,percentage of reticulocyte (Retic% ):0 .45% ~1 .76% ,absolute reticulocyte number(Retic#):(22~86)× 109/L ,mean corpuscular hemoglobin content of reticulocyte(CHr):30 . 1~36 .4 pg ,mean corpuscular volume of reticulocyte(MCVr):99 .5~113 .7 fL .Male ,Retic% :0 .54% ~1 .93% ,Retic# :(29~104)× 109/L ,CHr :32 .6~36 .6 pg ,MCVr :97 .6~112 .7 fL .The absolute reticulocyte of male is significantly higher than that of female;MCVr was significantly larger than mean corpuscular volume of mature erythrocytes ,which was also slightly larger in male than that in female;CHr was significantly higher than mean corpuscular hemoglobin of mature erythrocytes while mean corpuscular hemoglobin concentration of large reticulocytes was lower than that of mature erythrocytes;red blood cell volume distribution width of reticulocytes was lower than that of mature erythrocytes;the hemoglobin content distribution width of mature erythrocytes has a higher uniformity compared with reticulocytes .Conclusion The reference ranges of not commonly used parameters of reticulocytes were established ,and were compared with the corresponding parameters of red blood cells .
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Through various common domestic and foreign electronic sphygmomanometers to test blood pressure, we find that when measuring high blood pressure or low blood pressure, there is a mismatch between the maximum inflation pressure and the blood pressure measurement, which often results in repeatedly inflating and deflating as well as the problem of high inflation pressure. In order to solve these problems and find a suitable maximum inflation pressure, two intelligent pneumatic solutions based on identifying of pulse wave are suggested and 700 groups of blood pressure experiments are done, then the two solutions are verified by experiments. The experiment proved that these solutions proposed have good stability and accuracy, they can solve the problems appeared in measuring blood pressure effectively, at the same time, the second solution that estimate the maximum inflation pressure during inflation is considered as the best one.
Subject(s)
Humans , Blood Pressure , Blood Pressure Determination , Heart Rate , Hypertension , SphygmomanometersABSTRACT
Objective To design phacoemulsification handpiece with small size and high amplitude amplification coefficient.Methods By introducing the electro-mechanical vibration characteristics of piezoelectric transducer and ultrasonic horn,and adopting the equivalent circuit method and analytical method,respectively,the size of the ultrasonic horn,quarter wavelength piezoelectric transducer and ultrasonic horn were designed.Then,modal and harmonic analysis in finite element analysis software ANSYS11.0 were used to simulate the handpiece,and to optimize the size of the handpiece after adding on needle.Results The results indicated that the longitudinal vibration frequency and amplification coefficient were very close to theoretical design.The errors were 1.4％ and 5.8％,respectively.When piezoelectric ceramics were loaded with 300 V sinusoidal voltage,the displacement amplitude at the end of the needle reached 125.5 μm,which could meet the phacoemulsification surgery needs.Conclusion This design greatly reduced the size of the handpiece,and obtained high amplitude amplification coefficient.The simulation results sufficiently validated the theoretical design.
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<p><b>OBJECTIVE</b>Developing a high-frequency ultrasonic skin imaging system to obtain the high resolution ultrasonic image of the skin. And further analyzing the ultrasonic images of skin to explore the imaging characteristics of skin structure and then explore the value of high-frequency imaging in the application of skin diagnosis.</p><p><b>METHODS</b>50 MHz single element ultrasonic transducer, mechanic linear scanning method is used in the imaging system. The resolution and the ability of recognize the skin issue is verified by linear target scanning and clinical trials.</p><p><b>RESULTS</b>Both the axial and lateral resolution of the system reaches 50 microm. The subtle structure of normal skin tissue is clearly visible. Some diseases have obvious appearance in the image.</p><p><b>CONCLUSIONS</b>50 MHz ultrasonic skin imaging system is of high resolution and is valuable to skin structure detect and disease diagnosis.</p>