Abstract: Blood pressure is estimated in a non-constraining manner continuously and in real time. A biological signal collected from a person's dorsal part is analyzed, vibration in the human body ascribable to a blood flow rate change in a period from the ventricular filling period to the isovolumetric systole is captured, and the state of fluctuation of an index indicating the state of the in vivo vibration is further captured. This fluctuation index correlates with a person's blood pressure. Therefore, it is possible to estimate whether the blood pressure is in a range indicating a normal-range blood pressure or in a range indicating a high blood pressure, only by having the person sit or lie supine on a surface provided with a biological signal measurement device to measure a biological signal in a non-constraining manner, so as to make the biological signal measurement device contiguous with the person's dorsal part.

Abstract: To make it possible to grasp a biological condition, in particular, a condition ascribable to the movement of the heart. According to the embodiments, it is possible to find a boundary frequency between cardiac apex beat and heart sound. This makes it possible to find not only heart sound, but also cardiac apex beat, from a biological signal which is a collection of biological sound and in-vivo vibration. The boundary frequency is represented by a quadratic function of heart rate, and the use of correlation data based on the quadratic function makes it possible to find heart rate or a boundary frequency in real time. As a result, for example, if heart rate is known, the level of a boundary frequency is known. This facilitates inferring a health condition, for example, whether or not the heart is under stress, from a broader viewpoint than conventionally.

Abstract: There are provided a biological signal measurement device capable of obtaining a variety of biological information and applicable also to medical fields and the like, a biological state inference device, and a biological state inference system using these. The biological signal measurement device 1 of the present invention includes three biological signal detection units, namely, a left upper part biological signal detection unit 11, a right upper part biological signal detection unit 12, and a lower part biological signal detection unit 13. The biological state inference device 1 is capable of obtaining a highly precise inference-use processed waveform from which electrical noise has been removed, by using an appropriate combination of time-series data obtained from the three biological signal detection units 11 to 13.

Abstract: Blood pressure is estimated in a non-constraining manner continuously and in real time. A biological signal collected from a person's dorsal part is analyzed, vibration in the human body ascribable to a blood flow rate change in a period from the ventricular filling period to the isovolumetric systole is captured, and the state of fluctuation of an index indicating the state of the in vivo vibration is further captured. This fluctuation index correlates with a person's blood pressure. Therefore, it is possible to estimate whether the blood pressure is in a range indicating a normal-range blood pressure or in a range indicating a high blood pressure, only by having the person sit or lie supine on a surface provided with a biological signal measurement device to measure a biological signal in a non-constraining manner, so as to make the biological signal measurement device contiguous with the person's dorsal part.

Abstract: An apparatus for evaluating a vascular endothelial function, includes: a cuff pressure controlling unit configured to perform continuous pressure stimulation on a part of a body of a subject for a predetermined time, by using a cuff adapted to be wrapped around the part of the body of the subject; a cuff pressure detecting unit configured to detect a cuff pressure from an output of a pressure sensor connected to the cuff; a pulse wave detecting unit configured to detect a pulse wave from the output of the pressure sensor; and an analyzing unit configured to evaluate the vascular endothelial function by comparing vessel viscoelastic indexes which are obtained from the pulse wave detected in two of zones before, during, and after the pressure stimulation, and which exclude an amplitude of the pulse wave.

Abstract: An apparatus for evaluating a vascular endothelial function using a first cuff that occludes an artery of a patient, measuring pulse waves from pressure of a second cuff at a different position than the first cuff, and evaluating the vascular endothelial function using the pulse waves.

Abstract: An apparatus for evaluating a vascular endothelial function includes: a cuff, to be wound around a part of a body of a subject; a cuff pressure controller, configured to control a pressure of the cuff, and configured to apply continuous pressure stimulation; a cuff pressure detector, configured to detect the pressure of the cuff from output of a pressure sensor connected to the cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is applied; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is applied.

Abstract: A vessel wall monitoring apparatus includes: a first detecting unit which detects vessel diameter information based on first biological information obtained from a subject; a first producing unit which differentiates the vessel diameter information detected by the first detecting unit, to produce a vessel diameter function; a second detecting unit which detects blood pressure based on second biological information obtained from the subject; a second producing unit which performs a logarithmic operation on the blood pressure detected by the second detecting unit, to produce a logarithmic blood pressure function; and an outputting unit which produces an impedance model expression by using the vessel diameter function, the logarithmic blood pressure function, and mechanical characteristic values including a stiffness, viscosity, and inertia, and which calculates and outputs at least one of the stiffness, the viscosity, and the inertia based on the impedance model expression.

Abstract: A vessel wall monitoring apparatus includes: a first detecting unit which detects vessel diameter information based on first biological information obtained from a subject; a first producing unit which differentiates the vessel diameter information detected by the first detecting unit, to produce a vessel diameter function; a second detecting unit which detects blood pressure based on second biological information obtained from the subject; a second producing unit which performs a logarithmic operation on the blood pressure detected by the second detecting unit, to produce a logarithmic blood pressure function; and an outputting unit which produces an impedance model expression by using the vessel diameter function, the logarithmic blood pressure function, and mechanical characteristic values including a stiffness, viscosity, and inertia, and which calculates and outputs at least one of the stiffness, the viscosity, and the inertia based on the impedance model expression.

Abstract: An apparatus for evaluating a vascular endothelial function, includes: a first cuff, to be wound around a first body part of a subject; a second cuff, to be wound around a second body part of the subject; a cuff pressure controller, configured to control a cuff pressure of each of the first and second cuffs, and configured to perform continuous pressure stimulation on the first body part of the subject for a time period by using the first cuff; a cuff pressure detector, configured to detect the cuff pressure of the second cuff from an output of a pressure sensor connected to the second cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is performed; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is performed.

Abstract: An apparatus for evaluating a vascular endothelial function includes: a cuff, to be wound around a part of a body of a subject; a cuff pressure controller, configured to control a pressure of the cuff, and configured to apply continuous pressure stimulation; a cuff pressure detector, configured to detect the pressure of the cuff from output of a pressure sensor connected to the cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is applied; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is applied.

Abstract: A rapid vascular endothelium function examining method with improved reproducibility is provided. An apparatus for the method comprises systems for acquiring ultrasound images by an ultrasound probe, processing the acquired images and moving/rotating the ultrasound probe. The method comprises: a first step where the acquired image is processed so that the center of a blood vessel is laid on the center of the image; a second step where a series of operations for acquiring an image, processing the acquired image and moving the probe based on the processed result, are repeated so that the probe is moved in parallel to the blood vessel; a third step where the similar operations to the second step are executed so that the probe is moved in parallel to and immediately above the blood vessel; a fourth step for determining a blood vessel diameter from the finally acquired image at the third step.

Abstract: A rapid vascular endothelium function examining method with improved reproducibility is provided. An apparatus for the method comprises systems for acquiring ultrasound images by an ultrasound probe, processing the acquired images and moving/rotating the ultrasound probe. The method comprises: a first step where the acquired image is processed so that the center of a blood vessel is laid on the center of the image; a second step where a series of operations for acquiring an image, processing the acquired image and moving the probe based on the processed result, are repeated so that the probe is moved in parallel to the blood vessel; a third step where the similar operations to the second step are executed so that the probe is moved in parallel to and immediately above the blood vessel; a fourth step for determining a blood vessel diameter from the finally acquired image at the third step.