1. A multilayer piezoelectric element comprising a plurality of piezoelectric layers and a plurality of metal layers which are alternately stacked one upon another, wherein the metal layers include a plurality of high resistance metal layers having a higher electrical resistance than adjacent metal layers on the both sides.
2. The multilayer piezoelectric element according to claim 1, wherein the high resistance metal layers are arranged so as to interpose a plurality of different metal layers other than the high resistance metal layers.
3. The multilayer piezoelectric element according to claim 1, wherein the high resistance metal layers are arranged regularly.
4. The multilayer piezoelectric element according to claim 2, wherein the high resistance metal layers have an internal void ratio higher than a void ratio of the different metal layers.
5. The multilayer piezoelectric element according to claim 2, wherein the high resistance metal layers contain a high resistance component having a higher electrical resistance than the different metal layers, and have a larger high resistance component content than the different metal layers.
6. The multilayer piezoelectric element according to claim 2, wherein the high resistance metal layers have a smaller thickness than the different metal layers.
7. The multilayer piezoelectric element according to claim 1, wherein the electrical resistance of the high resistance metal layers is 110 to 1000 times greater than that of the piezoelectric layers.
8. The multilayer piezoelectric element according to claim 2, wherein the electrical resistance of the high resistance metal layers is at least 1000 times greater than that of the different metal layers.
9. A multilayer piezoelectric element comprising a plurality of piezoelectric layers and a plurality of metal layers which are alternately stacked one upon another, wherein at least one layer of the metal layers is formed by a plurality of partial metal layers interposed between the piezoelectric layers.
10. The multilayer piezoelectric element according to claim 9, wherein portions of the partial metal layers are connected at both ends in thickness directions of the partial metal layers to adjacent oppositely disposed piezoelectric layers, respectively, and the remaining portions of the partial metal layers are connected at only one end in the thickness direction of the partial metal layers to the piezoelectric layers, respectively.
11. The multilayer piezoelectric element according to claim 9, further comprising a plurality of metal layers composed of the partial metal layers.
12. The multilayer piezoelectric element according to claim 11, wherein the metal layers composed of the partial metal layers are arranged so as to interpose the piezoelectric layers, respectively.
13. The multilayer piezoelectric element according to claim 11, wherein the metal layers composed of the partial metal layers are arranged regularly.
14. The multilayer piezoelectric element according to claim 9, wherein the partial metal layers have one of a gradual decrease and a gradual increase in width with decreasing distance to the piezoelectric layers adjacent to the metal layers composed of the partial metal layers.
15. The multilayer piezoelectric element according to claim 9, wherein the partial metal layers are composed of one selected from the group consisting of silver, palladium and an alloy of these.
16. The multilayer piezoelectric element according to claim 9, wherein there are voids between the partial metal layers adjacent to each other.
17. The multilayer piezoelectric element according to claim 1, wherein a pair of external electrodes with the metal layers connected thereto are formed on side surfaces of a stacked body, respectively.
18. An injector comprising a container having an injection hole and a multilayer piezoelectric element according to claim 1, wherein a liquid filled in the container is discharged from the injection hole by the driving of the multilayer piezoelectric element.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for treating cardiovascular disease in a subject comprising administering a therapeutically effective amount of any one of compounds represented by the following Formula 1 to Formula 5 or pharmaceutically acceptable salt thereof to the subject in need thereof;
2. The method according to claim 1, wherein the compounds represented by Formula 1 to Formula 5 are prepared by extracting, isolating, and purifying from T. nucifera.
3. The method according to claim 1, wherein the cardiovascular disease is hyperlipidemia or atherosclerosis.