All issues
Volume 24, Issue 5
Displaying 1-11 of 11 articles from this issue
- |<
- <
- 1
- >
- >|
-
[in Japanese]1995 Volume 24 Issue 5 Pages 957
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSDownload PDF (179K) -
-How to Use Internet for Research and Development of Artificial Organs-M YOSHIZAWA1995 Volume 24 Issue 5 Pages 959-965
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSDownload PDF (8736K) -
M ENDO1995 Volume 24 Issue 5 Pages 966-975
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSDownload PDF (4863K) -
A TANAKA, M YOSHIZAWA, K ABE, T YAMBE, S NITTA, H TAKEDA, T CHINZEI, I ...1995 Volume 24 Issue 5 Pages 976-981
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSOne of the most difficult problems which prevent us from successfully controlling the total artificial heart is that we have not yet established any methods of setting the value of cardiac output regarded as a reference input to the control system. 1/R control method may be valid for avoiding this problem because it aims at making the recipient's circulatory center decide the value of cardiac output via peripheral vascular resistance. However, this method has a deficiency which consists in deciding an unknown parameter included in its algorithm in a trial and error manner. To cope with this deficiency, the present study proposed a new design strategy for TAH control. First, the cardiovascular system driven by a TAH was modelled as a two-input two-output system whose inputs are drive rate and peripheral vascular resistance and whose outputs are aortic pressure and cardiac output. Next, a decoupling controller was designed for the modelled system on the basis of the adaptive control theory. Computer simulation demonstrated that the proposed design strategy enables us to avoid the trial and error problem for deciding the unknown parameter and it can yield an automatic controller which can adapt to variation in characteristics of the cardiovascular system with individual or with a very long time span.View full abstractDownload PDF (1019K) -
T SAKAMOTO, E FURUTANI, H ONODERA, M IMAMURA, S MAETANI, M ARAKI1995 Volume 24 Issue 5 Pages 982-988
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSWe improved our blood pressure control system by adding two functions to the previous state-predictive control system. One function to identifies the specific values of the three parameters to cope with individual variations. These parameters are gain, time-constant and dead time, characterizing the blood pressure response to hypotensive drugs. The other function is a fail-safe mechanism that uses fuzzy logic to incorporate clinicians' expertise. The experiments were performed using adult mongrel dogs anesthetized with GOF under controlled respiration. The mean arterial pressure (MAP), recorded from the femoral artery, was lowered using trimethaphan camsilate with the target pressure set at 60mmHg. After introduction of these functions, the initial overshoot decreased from the previous level of 21.0mmHg to a maximum of 6.3mmHg and the MAP was adjusted to the target value more quickly (3.5-6.8min) than before (5.0-30min). Furthermore, our new system evaluated the animals' conditions, responding to their abnormal status before their conditions became critical. These results indicated the clinical applicability of our system.View full abstractDownload PDF (939K) -
Design of adsorbent for depletion of T lymphocytes from donor bone marrowT SATO, O TATSUZAWA, T AKAIKE1995 Volume 24 Issue 5 Pages 989-994
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSDepletion of T lymphocytes from donor bone marrow is useful for avoiding graft versus host disease (GVHD). We surveyed a technique to deplete T lymphocytes easily. Lactose-carrying polystyrene (PVLA) can selectively attach to soybean agglutinin (SBA) lectin which recognizes D-galactose. In order to evaluate the usefulness of PVLA and SBA coated materials for the agglutination of T lymphocytes, we examined the adhesion of galactose-bearing red blood cells and mononuclear cells to a PVLA-coated dish attached with SBA, and found that the number of adhered cells had increased according to the concentration of adsorbed PVLA on polystyrene plates and that the increase in immobilized SBA had elevated the number of adhered cells. On the other hand, few cells adhered to the PVLA free dish or the maltose-carrying polystyrene (PVMA) dish. The cells that adhered to the PVLA dish could be selectively detached by D-galactose. In conclusion, the interactions between PVLA and SBA are specific. It seems that PVLA is a useful material for the agglutination of soybean agglutinin lectin and D-galactosecarrying cells, and in the future, we may easily deplete T lymphocytes from donor bone marrow.View full abstractDownload PDF (3001K) -
-Analysis of their perioperative changesF MIYAWAKI, T TSUJI, K SUMA1995 Volume 24 Issue 5 Pages 995-1002
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSWe evaluated the influence of a cardiopulmonary bypass (CPB) system on coagulation and fibrinolytic factors: factors XII-II, AT III, plasminogen, protein C, vWF, TAT, PIC, FDP, fibrinogen, platelet count, PT and APTT. These were measured in 13 adult cases of open heart surgery (CPB time: 106±21min) before and after surgery, and on the first postoperative day (1 POD). All factors but APTT showed statistically significant changes with time, but the activities of factors XII, X and II, and protein C stayed within normal limits. The other factors went out of normal range. These factors, except factors VII and XI, were within or on the way back to normal range on 1 POD. The most abnormal activity of each coagulation factor was not so low as to cause postoperative bleeding tendency, which in fact was not found in any patients. These data suggest that the degree of activation of the coagulation and fibrinolytic cascades may be clinically acceptable although the CPB system significantly activates it. In addition, these data in this study can serve as control when a new CPB system is determined to have a better blood compatibility.View full abstractDownload PDF (1141K) -
Y FUKATA1995 Volume 24 Issue 5 Pages 1003-1007
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSThe aim of the present study is to elucidate the pharmacokinetics of nafamostat mesilate (FUT-175) under moderate hypothermic cardiopulmonary bypass (CPB). Using cases of open heart surgery, we measured blood FUT-175 concentration in CPB by combined use of heparin and FUT-175. Arterial and venous FUT-175 concentrations showed no significant difference 10, 30, and 60min following the start of FUT-175 administration, in vivo metabolism was shown to be remarkably depressed. Intra-circuit and atrial blood FUT-175 concentrations also showed no significant difference, and HPO-25H artificial lung intra-circuit adsorption on FUT-175 was no noted. Intravenous FUT-175 concentration was increased dose-dependently, being about 2.5-4 fold higher for the group of FUT-175, 2.0mg/kg/h continuous administration than the group of 1.5mg/kg/h administration. For the former group, venous blood FUT-175 concentration under moderate hypothermia was increased with time, being 1, 800 and 3, 650ng/ml 10 and 60min following the start of CPB, respectively, and began to be decreased in process of rewarming, being decreased by 67% 10min following the withdrawal.View full abstractDownload PDF (630K) -
An intraoperative evaluation with slide calipersJ UTOH, H GOTO, T HIRATA, Y MIYAUCHI1995 Volume 24 Issue 5 Pages 1008-1010
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSKnitted Dacron prostheses are known to dilate after surgery because of its configuration. Dilatation of gelatin-sealed knitted Dacron prosthesis (Gelseal®, Vascutek, UK) was evaluated in 9 patients who underwent surgical repair of abdominal aortic aneurysm. Prior to the implantation, the internal and external diameter of Gelseal were measured with slide calipers. Immediately after releasing the aortic clamp, the external diameter was also measured in the same fashion. Four weeks later, the external diameter was examined by CT scan. The size of Gelseal averaged 18.7±2.1mm. The internal and external diameters obtained from slide calipers measurements prior to the implantation were 19.2±2.2mm and 22.6±2.3mm. Immediately after the implantation, the external diameter revealed 22.7±2.4mm. Four weeks later, the external diameter averaged to 24.0±2.2mm. In conclusion, actual dilatation of the external diameter for one month following the implantation was 1.3mm (5.7%).View full abstractDownload PDF (388K) -
M HIRAI, A HASHIMOTO, S AOMI, A TAKAZAWA, H KOYANAGI1995 Volume 24 Issue 5 Pages 1011-1013
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSA new low porous vascular prosthesis (TORAY GRAFT) fabricated from ultra-fine polyester fibers was implanted in 22 patients for surgical reconstruction of the total aortic arch. Subjects included Stanford A type aortic dissection in 12, aortic arch aneurysm in 3, arch and descending thoracic aortic aneurysm in 2, aneurysm from ascending to descending thoracic aorta in 2, distal arch aneurysm in 2 and AAE+AR+arch aneurysm in 1. Before operation, the grafts with four branches were prepared and preclotted with albumin. There were four hospital deaths, but no graft-related problems. This new vascular prosthesis was soft and pliable, and easily anastmosed even in the pre-clotted condition, and little bleeding was observed at the site of anastomosis and the graft itself. Furthermore, excellent neointimal formation reported previously urges us to expect the fewer graft-related problems in the long term follow up. We thought that the clinical use of this graft made of ultra-fine polyester fibers is useful for the graft replacement of total aortic arch.View full abstractDownload PDF (563K) -
[in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...1995 Volume 24 Issue 5 Pages 1014-1021
Published: October 15, 1995
Released on J-STAGE: October 07, 2011
JOURNAL FREE ACCESSDownload PDF (1432K)
- |<
- <
- 1
- >
- >|