Abstract: An object is to provide a stent having, in a well-balanced manner, a high expansion force that enables the stent to come into close contact with an inner wall of a tubular organ, such as a digestive tract, to sufficiently expand a constricted part and good flexibility by which none of an ulcer and a perforation is generated at sites with which both end parts of the stent come into contact even when the stent is placed in a bent tubular organ. A stent of the disclosure is a stent formed in a tubular shape by braiding one or more wire rods. A radial force (RF) ranges from 0.02 N/mm to 0.04 N/mm, and a ratio (RF/AF) of the radial force (RF) to an axial force (AF) is 0.14 mm?1 or more. The stent of the disclosure preferably has a shortening of 35% or less.

Abstract: Novel acetylsalicylic acid derivatives having general formula (I) are provided, in which R.sup.1 is hydrogen or methyl; R.sup.2 is --O-- or --NH--; and W is hydroxy, halogen, lower alkoxy, lower alkenyloxy, lower alkynyloxy, cycloalkyloxy, aryloxy, aralkyloxy, acyloxy, or --N(R.sup.3)(R.sup.4) wherein the lower alkoxy, the lower alkenyloxy, the lower alkynyloxy, the cycloalkyloxy, the aryloxy, the aralkyloxy, and the acyloxy are optionally substituted with hydroxy, carboxyl, lower alkoxy, lower alkyl, halogen, nitro, and amino. The invention also pertains to a polymer made from such derivatives and a medical equipment containing the polymer. The polymer is useful in the prevention of platelet aggregation thereon.