摘要:
A process seal assembly adapted for installation to a process vessel opening. A probe with a probe connector connects to a rod inside a passageway of a housing adapted to be sealingly mounted to the process vessel opening. The rod has a first end coupled to the probe connector and a second end adapted to couple with a transmitter connector body. A rigid, electrically insulating spool is fastened in the passageway, with an outer spool surface fitting tightly to a wall of the passageway and an axial hole fitting tightly to the rod.
摘要:
A process seal made of a material such as polytetrafluoroethylene is used as a microwave window in a radar tank level gauge. The periphery of the process seal is surrounded by a metal containment ring that is fitted to the periphery to limit the amount of expansion outwardly of the process seal material as well as provide for localized loading at the periphery for clamping pressures on the seal. Electromagnetic radiation shielding is provided not only by the containment ring, but also by an EMI shielding O-ring mounted in a groove on a sealing end of the containment ring. A process environmental O-ring is carried by the process seal in an outer shoulder groove that is enclosed by the containment ring.
摘要:
A structure that can be used as a gastric band (and that may also have other uses as an implant elsewhere in a patient) includes a plurality of magnetic elements in a serial array that can be implanted so that the array extends in a circumferential direction around the patient's stomach (or other body tissue structure in the patient). Circumferentially adjacent magnetic elements magnetically attract one another to apply radial pressure to the tissue structure encompassed by the array, but those elements can also move apart in response to sufficient outward pressure from the encompassed tissue structure and/or the contents of (e.g., food in) that tissue structure. When used as a gastric band, the device can provide resistance to excessive food intake, which can help promote weight loss.
摘要:
Soft body tissue structure can be remodeled by shortening the distance between first and second portions of that tissue structure. First and second anchor structures are respectively implanted in the first and second portions of the tissue structure. These anchor structures are linked by a linking structure, the length of which between the anchor structures can be shortened to pull the tissue structure portions toward one another. Each of the anchor structures may include two screw structures that are driven into the associated tissue structure portion transverse to the linking structure and with a spacer between the two screws. The entire prosthesis can be implanted percutaneously if desired. An illustrative use of the prosthesis is to shorten the annulus of a patient's mitral valve, with at least a portion of the prosthesis implanted in the patient's coronary sinus.
摘要:
An improved method for testing a stent for a prosthetic valve includes applying a load with a fluid against a stented test structure in a backward direction with the stented test structure substantially blocking the flow of the fluid. The stented test structure includes a stent and a flexible membrane extending within the lumen defined by the stent with the flexible membrane having a plurality of contours connecting to the stent along the scallops. A corresponding testing apparatus includes a cyclic pressure applicator, a conduit connected to the cyclic pressure applicator, and a stented test structure mounted within the conduit to receive cyclic fluid pressures from the cyclic pressure applicator. The stented test structure includes a stent and a flexible membrane extending within the lumen defined by the stent. The flexible membrane substantially blocks flow of the fluid in a backward direction and does not fully open upon application of the fluid pressure in a forward direction.
摘要:
Valved prostheses include a support structure and a plurality of flexible polymer leaflets connected to the support structure, in which the leaflets have an improved structural design. The support structure has a plurality of commissure supports and scallops between the commissure supports. Generally, the flexible polymer leaflets project away from the support structure at an attachment edge where the leaflets connect to the support structure. In particular embodiments, the leaflets at the attachment edge are at an angle from about 5 degrees to about 85 degrees relative to a plane normal to the valve axis. In some embodiments, the flexible polymer leaflets having a coaptation depth from about 0.3 times the valve radius to about 0.8 times the valve radius. In further embodiments, the flexible polymer leaflets form a valve with a valve height from about one times the valve radius to about 2 times the valve radius and have leaflet lengths at least about 1 millimeter greater than the valve radius.
摘要:
A structure that can be used as a gastric band (and that may also have other uses as an implant elsewhere in a patient) includes a plurality of magnetic elements in a serial array that can be implanted so that the array extends in a circumferential direction around the patient's stomach (or other body tissue structure in the patient). Circumferentially adjacent magnetic elements magnetically attract one another to apply radial pressure to the tissue structure encompassed by the array, but those elements can also move apart in response to sufficient outward pressure from the encompassed tissue structure and/or the contents of (e.g., food in) that tissue structure. When used as a gastric band, the device can provide resistance to excessive food intake, which can help promote weight loss.
摘要:
Methods and apparatus are provided that gather a patient's body tissue and then secure the gathered tissue in a reduced area utilizing a securing structure. The securing structure mainly resides on one side of the tissue to minimize or eliminate both foreign material and the amount of manipulation or activity on the other side of the tissue. The securing device is matched to the desired amount of tissue manipulation to minimize the structure. The gathered and secured tissue can surround a septal defect to obstruct or close the defect itself.
摘要:
Improved dip coating methods and mandrels for forming polymer leaflets and valve prostheses generally involve one or more features on the mandrel that facilitate the processing. The mandrel has a top surface and an outer surface comprising a plurality of ridges and contoured surfaces extending to the ridges. An edge on the mandrel separates the top surface and the contoured surfaces, with the mandrel edge corresponding to the free edge of the leaflet. In preferred embodiments, the edge separating the top surface from the contoured surfaces is sharp. The polymer formed on the top surface can be efficiently separated from the remaining portions of the polymer structure to form the free edges of the leaflets.
摘要:
A prosthetic heart valve for replacing a native heart valve is provided and includes a generally circular heart valve body having an inner wall defining a lumen configured to allow blood flow therethrough. Occluders are configured to rotate about opposed occluder ends between an open position and a closed position. The minor radius arcs cooperate with the occluders to allow the occluders to block blood flow through lumen when in a closed position yet provide an increased lumen when the occluders are in an open position.