Search PubMed⌕ Search

Biomedical subjects

H Imamura

Publications and source records attributed to H Imamura.

At least 361 records · Page 20Linked to original sources

A prosthetic myocardium: hemodynamic advantages.

When a large left ventricular aneurysm or infarct is excised, a frequent complication is inability of the left ventricle to regain adequate performance. Reduction in ventricular volume and impairment of myocardial contractility, either of which can diminish cardiac output to levels incompatible with life, are probably the main factors that lead to left ventricular failure after such surgery. A prototype prosthetic myocardium, designed to mimic the actions of the left ventricular myocardium, offers a direct means of restoring both ventricular volume and contractility after excision of a large portion of the left ventricle. In dog experiments 17 +/- 1.1% (AV +/- SE) of the left ventricle was infarcted and excised under cardiopulmonary bypass. The prosthetic myocardium was implanted and activated, and changes in hemodynamic parameters produced by the assist device were studied. "On" to "off" changes in 11 dogs in congestive failure averaged over the course of the experiment were as follows: m-AoP was increased 19 +/- 1.7% (Mean +/- SE): LV Syst. Press. was increased 24 +/- 1.7%; SV was increased 34 +/- 3.2%, LVEDP and m-LAP were reduced 43 +/- 2.4% and 22 +/- 1.4% respectively; and LVSW incrdased 88 +/- 8.8%. With these hemodynamic benefits this prototype represents an encouraging step toward the development of a device for orthotopic replacement of damaged myocardium.

Animals↗

[Antibacterial activity of cefoperazone against anaerobic bacteria (author's transl)].

The following results were obtained from the comparison of cefoperazone (CPZ) with cefazolin (CEZ), cephalothin (CET) and cefoxitin (CFX) in respect to their antibacterial action against anaerobic bacteria: 1) CPZ showed an antibacterial spectrum which was comparable to those of the known antibiotics, CEZ, CET and CFX. CPZ was particularly effective against anaerobic Gram-positive bacteria. 2) CPZ showed a distribution of susceptibility against clinically isolated strains which was comparable to those of CEZ, CET and CFX, CPZ was slightly inferior to CFX against B. fragilis and B. thetaiotaomicron, but was somewhat superior to any of CEZ, CET and CFX against anaerobic Gram-positive rods and B. distasonis. 3) The susceptibility of B. fragilis and F. necrophorum to CPZ decreased with an increase in the amount of inoculation, while C. perfringens and P. asaccharolyticus did not show any difference in susceptibility with the amount of inoculation. 4) The values of MIC and MBC of CPZ showed good coincidence with each other, thereby testifying its superior bactericidal action. 5) Natural resistant mutants were not obtained. 6) According to the examination of resistance in a test tube, P. variabilis did not show any appreciable increase in resistance, but F. varium increased its resistance rapidly. 7) CPZ was inferior only to CFX in stability against the beta-lactamase of B. fragilis. All of CEZ, CET and CMD lacked stability against the beta-lactamase of B. fragilis. 8) CPZ was found effective for the treatment of experimental subcutaneous abscess in mice caused by F. necrophorum.

Abscess↗