Abstract: A necktie comprising a knot support, an outer tie secured to the knot support and being positionable about the knot support to provide a knot, an inner tie releasably secured to the knot support comprising an upper loop to be worn about the neck of a wearer, an adjusting means positioned on the inner tie, and a tie end adjacent to the upper loop, the adjusting means including a grasping means having an aperture therein; and a securing means for releasably securing the inner tie to the knot support including a stud positioned on the rear surface of the knot support and a protruding securing means also positioned on the rear surface of the knot support, wherein the grasping means is located within the protruding securing means and the stud is positioned within the aperture of the grasping means when the inner tie is secured to the knot support.

Abstract: A prosthetic heart valve comprising a stent having an annular base and a plurality of legs extending upwardly from said base; a valve element circumscribing said stent and attached thereto, said valving element comprising a number of cooperating valve leaflets equal to the number of said legs; and a layer of biologically-compatible material secured to said stent and positioned between said stent and said leaflets, said layer having a smooth, non-abrasive outer surface and covering all of the surfaces of said stent that, in the absence of said layer, would contact the mobile portions of said leaflets during the normal function of the valve.

Abstract: Novel tubular prostheses, e.g. vascular or ureteral prostheses, prepared by sewing the opposed edges of a sheet of pericardial tissue together with a thread to form a longitudinal seam are disclosed. By disposing the thread in a suitable configuration along the seam, for example in a plurality of stitches each of which is secured with a knot, a tubular prosthesis results that can be cut transversely between its ends without unravelling the thread and substantially damaging the same. Use of bovine pericardial tissue is preferred since the range of compliances of tubular prostheses made therefrom is approximately comparable to the range in human arteries and veins, whereas tubular prostheses made from porcine pericardial tissue tend to be too compliant.