A subject of the invention is the compounds of formula ;in which R1, R2, R3, R4 and R have the meanings indicated in the description, their preparation process, their use as medicaments having an antagonist activity on the vitronectin receptor and the pharmaceutical compositions containing them. Of first and second waist regions at least the first waist region is contractible. A first flexible ring is positioned between the first bushing and the center shaft, the first flexible ring compressed therebetween, and a second flexible ring is positioned between the second bushing and the center shaft, the second flexible ring compressed therebetween. thuringiensis \u03b4-endotoxins. The wiring layer is formed on the interlayer dielectric layer in such a way as to contact the plug, resulting in the wiring layer electrically connected to the connection portion by way of the plug. Based on image data read from a null-image prior to optical reading of a manuscript, an abnormal pixel detecting part detects the position of the abnormal pixel caused by the dust and others lying on a contact glass equipped between the manuscript and a CCD.