Abstract: A probe for insertion into a living body includes a sheath configured to be inserted into a living body, and a shaft positioned in the sheath. The shaft includes a tip portion configured to obtain diagnostic data at a distal portion thereof. The sheath includes a resin layer or a metal layer of at least one layer, and wherein the resin layer or the metal layer includes a spiral-shaped slit which is continuous from a distal portion to a proximal portion. The spiral-shaped slit includes a distal slit portion having the highest slit density, a middle slit portion which is continuous with the distal slit portion and which also has a lower slit density than the distal slit portion, and a proximal slit portion which is continuous with the middle slit portion and which also has a higher slit density than the middle slit portion.

Abstract: A probe for insertion into a living body includes a sheath configured to be inserted into a living body, and a shaft positioned in the sheath. The shaft includes a tip portion configured to obtain diagnostic data at a distal portion thereof. The sheath includes a resin layer or a metal layer of at least one layer, and wherein the resin layer or the metal layer includes a spiral-shaped slit which is continuous from a distal portion to a proximal portion. The spiral-shaped slit includes a distal slit portion having the highest slit density, a middle slit portion which is continuous with the distal slit portion and which also has a lower slit density than the distal slit portion, and a proximal slit portion which is continuous with the middle slit portion and which also has a higher slit density than the middle slit portion.

Abstract: A dilatation catheter has a tubular proximal shaft having relatively high rigidity, a tubular distal shaft having rigidity lower than that of the proximal shaft, a tubular intermediate section interposed between the proximal shaft and the distal shaft, a hub mounted on the proximal end portion of the proximal shaft, a balloon arranged on the distal end portion of the distal shaft so as to be in fluid communication with the distal shaft, and an inner shaft into which a guide wire can be inserted. The distal end portion of the proximal shaft can be inserted into the intermediate section to form an insertion portion having a spiral slit.

Abstract: A catheter includes a tubular proximal shaft having relatively high rigidity, a tubular distal shaft having rigidity lower than that of the proximal shaft, a tubular intermediate section disposed between the proximal shaft and the distal shaft, a hub arranged near a proximal end of the proximal shaft, a balloon provided to a distal portion of the distal shaft to be in fluid communication, and a guide wire lumen having a distal aperture located on a distal end side of the distal end of the balloon and a proximal aperture located on a proximal end side of the proximal end of the balloon, through which a guide wire is inserted, wherein a reinforcing member consisting of a braided member made of at least one linear member, is embedded in the intermediate section. The catheter is capable of effectively avoiding kink caused by heavy concentration of flexural stress.

Abstract: Catheter tube 2 has a multiple of small bead-like projections 21 formed on the inner surface. The inner surface of the tube 2 comprises projections 21 and flat areas 22. A guide wire inserted into the lumen 5 of the tube 2 contacts its inner surface only at the projections 21. The catheter tube 2 has the inner surface embossed in such a way that the guide wire can be manipulated with high efficiency even if the diameter of the tube is very small.

Abstract: A catheter balloon having a base layer formed of a high-strength polymer and one or more covering layers formed over at least one surface of said base layer of the same flexible polymer or different flexible polymers having a elongation at break close to that of said high-strength polymer and being more flexible than said high-strength polymer, and has a wall thickness of 25 .mu.m or thinner.A balloon having a base layer formed of a high-strength polymer and one or more covering layers formed over at least one surface of said base layer of the same flexible polymer or different flexible polymers more flexible than said high-strength polymer, and has a wall thickness of 25 .mu.m or thinner, said covering layer or covering layers together bearing 10% or more part of the bursting stress of the balloon.A balloon catheter, especially blood vessel dilating catheter, equipped with any of the above balloons.

Abstract: Catheter tube 2 has a multiple of small bead-like projections 21 formed on the inner surface. The inner surface of the tube 2 comprises projections 21 and flat areas 22. A guide wire inserted into the lumen 5 of the tube 2 contacts its inner surface only at the projections 21. The catheter tube 2 has the inner surface embossed in such a way that the guide wire can be manipulated with high efficiency even if the diameter of the tube is very small.

Abstract: A connector has an instrument insertion passage which is provided with a seal member made from an elastic member formed with a seal member passage having a narrowed portion. When a knob is grasped and turned clockwise to turn a control body, the control body is forced into the connector and abuts the seal member causing the seal member to deform so as to reduce the inner diameter of the narrowed portion of the seal member, thereby enabling an instrument to be held by the narrowed portion in a fluid-tight manner which allows the instrument to be slidable through the connector. Also, by turning the control body further into the connector, the deformation of the seal member can be increased to cause the narrowed portion to fix the instrument in place in a manner that prevents the instrument from being slid through the connector 1.

Abstract: A balloon catheter having a balloon which is produced by molding polyarylenesulfide or an alloy thereof wherein polyarylenesulfide is a main constituent, and the balloon is provided with excellent dimensional stability as well as sufficient softness and flexibility, leading to an improved trackability of the catheter to reach the target lesion.

Abstract: A balloon for a blood vessel-dilating catheter is fabricated from a biaxially oriented film of an aromatic polyamide or an alloy thereof. The balloon has a calculated modulus of elasticity of from 70 to 190 kg/mm.sup.2. When the balloon is fabricated from an alloy of an aromatic polyamide, the alloy may contain up to 50% by weight of an aliphatic polyamide. The balloon of the invention is soft and flexible as well as dimensionally stable. Therefore, the balloon catheter has a high trackability, and may be inserted into the blood vessel without inducing any injury in the inner surface of the blood vessel. The balloon of the invention also has a good blood compatibility.

Abstract: An inner diameter retaining instrument for holding a predetermined expansion state of the lumen of a tubular organ such as a blood vessel, a digestive tract, or a windpipe is disclosed. This instrument is formed into a cylindrical shape or substantially cylindrical shape by a unidirectional shape memory alloy. The outer diameter of the cylindrical body at its transformation temperature (e.g., a temperature higher than a body temperature) is set to be smaller than the inner diameter of a tubular organ in which the cylindrical body is introduced. The instrument can be deformed to be radially expanded at, e.g., the body temperature or lower. As a cylindrical shape, a coil-like shape, a shape having a spiral section, a shape having a slit in its longitudinal direction, or a mesh-like shape can be arbitrarily selected.

Abstract: A tubular-organ expansion unit has a cylindrical body made of a shape memory alloy which is capable of maintaining the inside diameter of a tubular body organ. The tubular-organ expansion unit includes an X-ray contrast enhancer for improving the X-ray contrast of the tubular-organ expansion unit relative to the X-ray contrast of the tubular-organ expansion unit before the X-ray enhancer was provided on the expansion unit. In a tubular-organ expansion apparatus and a method for indwelling the tubular-organ expansion unit into a lumen of a tubular body organ, the shape memory alloy of the tubular-organ expansion unit will change its radial dimension in response to changes in temperature. The shape memory alloy may be bidirectional.

Abstract: The expanding/contracting accelerations of shock absorbers on a motor vehicle are detected and compared with preset accelerations, respectively, by an electronic controller, which individually varies the damping forces of the shock absorbers as a result of the comparison. The electronic controller corrects the preset accelerations so that the damping forces of the shock absorbers will be switched over at a uniform frequency or the damping forces of the front left and rear left shock absorbers and the damping forces of the front right and rear right shock absorbers will be switched over at a constant frequency.

Abstract: A variable-damping-force shock absorber includes a piezoelectric actuator for producing a displacement, a hydraulic pressure chamber filled with a working oil and having a volume variable in response to the displacement produced by said piezoelectric actuator, and a plunger slidably disposed in a sleeve and reciprocally movable in response to a change in the volume of said hydraulic pressure chamber. The sleeve and said plunger define therebetween a gap communicating with said hydraulic pressure chamber. A supply passage for supplying a working oil from an external working oil source into said hydraulic pressure chamber extends through the gap. A leakage of the working oil from the hydraulic pressure chamber through the gap can automatically be compensated for by working oil supplied through the supply passage. Since the working oil leaks from and is supplied into the hydraulic pressure chamber through the gap, the leakage and supply of the working oil are kept in equilibrium.

Abstract: A damping force detecting apparatus for detecting a damping force of a variable damping force type shock absorber including a cylinder and a piston slidably inserted thereinto. The damping force detecting apparatus comprises a piezoelectric element assembly for generating a charge corresponding to a pressure applied thereto and a pressurizing device for pressurizing the piezoelectric element assembly. The piezoelectric element assembly has a diameter smaller than a cylindrical piston rod fixedly secured to the piston and is housed therein. The pressurizing device is screwed into the piston rod so as to be in contact relation to the piezoelectric element assembly for pressurizing the piezoelectric element assembly in correspondance with a distortion of the piston rod generated in the sliding directions of the piston with respect to the cylinder due to expanding and contracting action of the shock absorber.

Abstract: A shock absorber system for controlling the damping forces of shock absorbers comprising a drive apparatus for operating a piezo-actuator which is constructed by laminating a plurality of piezoelectric elements. The drive apparatus comprises a high-voltage generation circuit for generating a high voltage and a charging and discharging circuit for applying the high voltage, generated by the high-voltage generation circuit, to the piezo-actuator and for discharging an electric charge charged in the piezo-actuator due to the application of the high voltage thereto, the charging and discharging results in expansion and contraction of the piezo-actuator. Also included in the drive apparatus is an abnormality detection circuit for detecting a charging current or a discharging current passing through a charging or discharging current passage coupled to the piezo-actuator at the time of charging or discharging by the charging and discharging circuit.

Abstract: A shock absorber which selectively produces different magnitudes of damping forces includes a cylinder and a piston slidably disposed in the cylinder and dividing an interior space of the cylinder into first and second fluid chambers filled with a fluid. A housing assembly coupled to the piston has a main fluid passage providing fluid communication between the first and second fluid chambers at all times and an auxiliary fluid passage providing selective fluid communication between the first and second fluid chambers. The auxiliary fluid passage can be opened to provide fluid communication between the first and second fluid chamber in response to an external control signal. The auxiliary fluid passage can be closed to cut off fluid communication between the first and second fluid chambers when the speed of relative movement of the cylinder and the piston is substantially zero, i.e., when the speed of expansion and contraction of the shock absorber is substantially zero.

Abstract: A balloon catheter assembly including a balloon and a catheter. The catheter has a chuck and a multi-tube unit including at least an inner tube and an outer tube arranged slidably and coaxially with the inner tube. The balloon is removably fixed to the distal portion of the inner tube by the chuck which is pulled into the outer tube to be closed, and which is extended from the outer tube to be opened. The catheter is introduced to a required dwelling portion in a blood vessel by a tubular guide sheath having an inner diameter such that the guide sheath admits the catheter, and the expanded balloon is left in the dwelling portion to occlude the blood vessel.

Abstract: An extruder apparatus for molding a tube used for guiding a rod-like medical instrument into a living body. The resulting tubular body is made of a synthetic resin and has a longitudinal hollow portion to permit the passage of the rod-like medical instrument. The whole of the tubular body is formed to have a chemical uniformity, but at least one brittle portion such as a weld line is longitudinally formed over the entire length (or almost the entire length except the tip portion) of the tubular body. The brittle portion is formed by a die including a nozzle having a resin flow passageway of annular cross section. At least one baffle extends radially into the passageway for substantially temporarily splitting the flow which is then recombined to form the brittle portion.

Abstract: A method of firmly securing a catheter body to a surface portion of human skin, without causing the catheter body to be bent or reducing the diameter of the inner passage of the catheter body. This method employs a catheter-securing member which comprises a cylindrical body for allowing the catheter body to be slidably inserted therein, and a slit is provided along the axial direction of the cylindrical body. In this method a ligature is first pierced through a surface portion of human skin and tied over the surface of human skin, leaving a pair of free end portions extending out of the skin, and then the cylindrical body is secured with the free end portions of the ligature by winding the ligature around the cylindrical body and fastening them.