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101.
H. Tazawa Y. Hashimoto M. Takami Y. Yufu G. C. Whittow 《Medical & biological engineering & computing》1993,31(2):129-134
Using a flexible piezoelectric film, the authors developed a simple system to determine noninvasively the heart rate of chicken
embryos and hatchlings. The film was piezoelectric polyvinylidene fluoride (PVDF), which is sensitive enough to detect cardiogenic
ballistic movements of the egg (ballistocardiogram (BCG)) and precordial movements of the hatchling attributable to cardiac
contractions (apexcardiogram (ACG)). The BCG could be detected, during the second half of incubation, by placing the egg on
the PVDF film on a soft substrate. The detected signal was found to be a measure of movement velocity. The ACG could be measured
when the hatchling's chest wall made contact with the PVDF film installed in a box in which the hatchling was confined. The
heart rate was counted from the lag time of autocorrelation calculated for a certain time segment (e.g. 2s) of the BCG and
ACG recordings. 相似文献
102.
圆孔外面的观察和测量及其面积的回归方程 总被引:4,自引:0,他引:4
60具成人颅骨颅底外面的圆孔观察和测量结果表明:圆孔多呈圆形,其次是卵圆形,其它形较少见.据圆孔与翼突外侧板根部延长线的位置关系,分圆孔位置为三型.圆孔外面观的各项测值左右间均无统计学差异,但其中管性圆孔管长度个体差异较大.圆孔的面积左右比较对称者占3.33±2.34%,左>右者占65.51±6.30%,右>左者占34.48±6.30%.圆孔面积左右对称性比较,对临床诊断疾病有参考意义.其面积的回归方程可由其长、宽径乘积推算 . 相似文献
103.
J. H. Battocletti R. E. Halbach A. Sances Jun S. J. Larson R. L. Bowman V. Kudravcev 《Medical & biological engineering & computing》1979,17(2):183-191
A new flat crossed-coil nuclear magnetic resonance (n.m.r.) detector can be used to measure flood flow at many regions of
the body, is introduced. It is compared, bothin vitro andin vivo, with the already proven cylindrical crossed-coil n.m.r. detector. Both detectors use a single high-field homogenous magnet.
A single-sideband receiver reduces the effect of transmitter leakage into the receiver coil to allow the use of a high-level
transmitter field. Preliminary application of the flat crossed-coil detector to the detection of cerebral blood flow is presented. 相似文献
104.
Dr. S. Ichioka M. Iwasaka M. Shibata K. Harii A. Kamiya S. Ueno 《Medical & biological engineering & computing》1998,36(1):91-95
There have been few studies of the effect of static magnetic fields on microcirculatory haemodynamics in vivo. The rat skinfold
transparent chamber technique was used, which provides an excellent means of observing and quantifying direct in vivo microvascular
haemodynamic responses to static magnetic fields up to 8 T. An intravital videomicroscope was used to measure the changes
in blood flow before and after exposure to a magnetic field for 20 min in a horizontal type superconducting magnet with a
bore 100 mm in diameter and 700 mm long. After exposure, microcirculatory blood flow showed an initial increase for about
5 min followed by a gradual decrease and a return to the control value. It is hypothesised that these changes represent rebound
hyperaemia following reduced blood flow during exposure. 相似文献
105.
红外多波长无创人体血糖检测阵列模型的研究 总被引:2,自引:0,他引:2
无创血糖监测不仅可以减少患者的痛苦,还能进行连续测量,从而降低并发症的发生,它是一种不需收集血样进行体内血糖浓度测量的新技术。本文根据朗伯-比尔定律(The Lambert—Beer Law)原理,为克服无创血糖检测研究中的难点和缺陷,详细分析了血糖红外光谱的吸收特性,利用阵列技术设计了红外多波长无创血糖检测传感器阵列模型,对关键技术进行了讨论。用ME算法建立了信号检测和标定数学模型,结合了人体各种影响因素,使红外无创血糖检测的精度和稳定性得到了改善。列举了详细的实验实施步骤,同时叙述了系统调试的详细过程,讨论了无创血糖检测中需要注意的问题。 相似文献
106.
Background
As assessment with inertial-measurement-units (IMUs) increases in research and in clinics, it is important to be aware of the repeatability of these sensors. The objectives of this experiment were to evaluate the measurement repeatability of IMU joint angles using a repeatable robot controller and an anthropomorphic leg phantom and to determine effects of joint speed and sensor positioning on the angles collected by these sensors. Comparisons to an electro-goniometer and three-dimensional (3D) motion capture cameras were also completed.Methods
Two dual-IMU setups (posterior and lateral) were tested concurrently with an electro-goniometer and 3D motion capture cameras using a repeatable robot controller and a leg phantom. All modalities were attached to the phantom, which was flexed 10 times using a pre-programmed motion pathway during each test. Mean angles were compared across tests. Effects of joint speed, sensor re-positioning, and anatomical placement of the sensors on repeatability were assessed.Results
Re-positioning caused greater deviation to the maximum and minimum angles than differences in speed. Overall, the means?±?standard deviations, and 95% confidence intervals of the maximum angles across all tests for the 3D camera markers, electro-goniometer, posterior IMUs, and lateral IMUs were 119.4?±?0.3° (119.4, 119.5), 112.4?±?0.5° (112.3, 112.5), 116.2?±?2.4° (115.7, 116.7), and 118.3?±?1.1° (118.1, 118.6).Conclusions
Both posterior and lateral IMU setups demonstrated acceptable repeatability in measurement of range of motion that was advantageous to manual goniometer methods. Posterior and lateral IMU setups demonstrated overlapping standard deviations about their means. 相似文献107.
本文研制的袖套式数字血压计,基于示波法原理,通过采用多通道、多气阀以及软件上的改进,改善了目前一般数字血压计的不足,与一般袖套式数字血压计相比,具有重复性好、测量范围大(成人和儿童都可测量)等优点。 相似文献
108.
M. O. Toll 《Medical & biological engineering & computing》1984,22(1):2-5
The direct measurement of blood pressure has found widespread use in intensive care units, operating rooms, and in emergency
departments. Infection, air embolism and thrombosis are some of the risks to patients associated with both the cannulation
procedure and with the apparatus used in the blood-pressure measuring process. Although there is constant revision in an attempt
to reduce these risks, they cannot be completely eliminated. The need for direct blood-pressure measurements and the physiological
effects of air embolism and thrombosis are reviewed. Infection and problems related to the techniques used to insert the catheters
are not discussed. 相似文献
109.
利用脉搏波特征参数连续测量血压的方法研究 总被引:11,自引:0,他引:11
通过研究血压与脉搏波特征参数的关系,提出了一个选择多个与血压相关的脉搏波特征参数,通过回归分析建立适合不同人的特征方程,进行血压的连续测量的新方法,为了验证测量结果的准确性;研制了张力计。实验结果表明:该方法具有较高的测量精度,可以应用于临床危重病人的血压监护和一般医学研究中,经过进一步地改进和完善后可应用于载人航天和日常动态环境。 相似文献
110.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献