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61.
Clinical effects of percutaneous cardiopulmonary support in severe heart failure: early results and analysis of complications. 总被引:2,自引:0,他引:2
Shigeru Sakamoto Junichi Matsubara Toshiaki Matsubara Yasuhiro Nagayoshi Shinji Shono Hisateru Nishizawa Masaaki Kanno Katsunori Takeuchi Toshimichi Nonaka Jun Kyosawa 《Annals of thoracic and cardiovascular surgery》2003,9(2):105-110
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage. 相似文献
62.
Yukiya Hashimoto Toshiko Koue Yuko Otsuki Masato Yasuhara Ryohei Hori Ken-ichi Inui 《Journal of pharmacokinetics and pharmacodynamics》1995,23(2):205-216
A simulation study was conducted to compare the cost and performance of various models for population analysis of the steady
state pharmacokinetic data arising from a one-compartment model with Michaelis-Menten elimination. The usual Michaelis-Menten
model (MM) and its variants provide no estimate of the volume of distribution, and generally give poor estimates of the maximal
elimination rate and the Michaelis-Menten constant. The exact solution to the Michaelis-Menten differential equation (TRUE)
requires a precise analysis method designed for estimation of population pharmacokinetic parameters (the first-order conditional
estimation method) and also considerable computational time to estimate population mean parameters accurately. The one-compartment
model with dose-dependent clearance (DDCL), in conjunction with the first-order conditional estimation or Laplacian method,
ran approximately 20-fold faster than TRUE and gave accurate population mean parameters for a drug having a long biological
half-life relative to the dosing interval. These findings suggest that the well-known MM and its variants should be used carefully
for the analysis of blood concentrations of a drug with Michaelis-Menten elimination kinetics, and that TRUE, in conjunction
with a precise analysis method, should be considered for estimating population pharmacokinetic parameters. In addition, DDCL
is a promising alternative to TRUE with respect to computation time, when the dosing interval is short relative to the biological
half-life of a drug.
This work was supported in part by the Epilepsy Research Foundation, the Nakatomi Foundation, and a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science, and Culture of Japan. 相似文献
63.
Naoki Hori Hakuo Takahashi‡ Takeshi Okanoue Yoshihiko Sawa Takashi Mori Shiro Takami Manabu Yoshimura† Kei Kashima 《Clinical and experimental pharmacology & physiology》1995,22(8):506-511
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation. 相似文献
64.
Hemodynamic and volume changes induced by recombinant human erythropoietin (rHuEPO) treatment were investigated in 12 chronic hemodialysis patients with refractory anemia. After rHuEPO administration for 49 to 151 days, hematocrit (Ht) significantly improved from 19.4 +/- 2.3 to 30.1 +/- 1.1% (Mean +/- SD). Mean blood pressure (MBP) increased slightly but significantly from 78.8 +/- 13.2 to 88.9 +/- 16.9 mmHg. Hemodynamically, total peripheral resistance index (TPRI) increased significantly from 1,444 +/- 367 to 2,146 +/- 470 dynes.sec.cm-5.m2, while cardiac index (CI) decreased significantly from 4.49 +/- 0.85 to 3.37 +/- 0.60 l/min/m2. Both pulse rate (PR) and stroke volume index (SVI) also decreased significantly, but blood volume (BV) remained unchanged. Plasma renin activity and plasma norepinephrine decreased significantly. There were positive correlations between the change of MBP and that of CI, and between the change in CI and that of BV, respectively (p less than 0.05 or less). In conclusion the improvement of anemia using rHuEPO is hemodynamically associated with an increase in TPRI and a decrease in CI as well. Blood pressure elevation seems to be caused by an inappropriately minor reduction of CI. The contribution of humoral factors is not suggested. 相似文献
65.
Differential biologic effects resulting from bimodal binding of recombinant human tumor necrosis factor to myeloid leukemia cells 总被引:2,自引:0,他引:2
Human recombinant tumor necrosis factor (rTNF) bound to ML-1 and HL-60 human myeloid leukemia cells in a bimodal manner. Saturable high- affinity binding was maximal at approximately 3 nmol/L rTNF, whereas saturable low-affinity binding reached its maximum at approximately 30 nmol/L. As analyzed by computer program, the observed data fit a two- receptor site model, with p less than .05. High-affinity binding concentrations of rTNF caused the differentiation of both cell lines, whereas low-affinity binding concentrations abolished this effect in a concentration-dependent manner. Thus, the type of biologic response elicited with rTNF in these cells is a function of the concentration at which the factor is applied. If generally applicable, this bimodal effect may require consideration when rTNF is to be used therapeutically. 相似文献
66.
67.
68.
Nobuyuki Tanaka Yutaka Kimijima Masafumi Mimura Akira Yamaguchi Shizuko Ichinose Gen-iku Kohama Masaaki Satoh 《Medical Electron Microscopy》1998,31(3):156-161
A rare case of lentigo maligna in the oral cavity was investigated by light and electron microscopy. Cutaneous lentigo malignas often develop to malignant melanomas. However, the electron microscopic examination revealed that even though there were a large number of melanosomes, most of them were late stage and had membrane structure, and positive staining with HMB-45 was not recognized. From our findings, it is difficult to conclude that oral lentigo malignas develop malignant melanomas, and thus further studies are needed. 相似文献
69.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis
of microscopic and macroscopic findings postembolization.
Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients
who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the
basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding
type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings:
single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth
type.
Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing
type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis)
to the SNE type (21%), and the other types (9%). 相似文献
70.
Y Ichihashi M Hori O Tatsuzawa N Okabe H Wakasugi H Yoshioka K Fujita H Sakata C Ishida H Kakehashi 《The Japanese journal of antibiotics》1988,41(5):538-548
A multiclinic study of gentamicin (GM) given by intravenous drip infusion was carried out by the Gentamicin Pediatric Study Group. The results are summarized as follows: 1. Upon intravenous drip infusion of GM at a dose range of 2.0-2.5 mg/kg over a period of 0.5-1 hour, therapeutically effective serum concentrations of 4-12 micrograms/ml were obtained. These values are similar to reported values in previous studies using GM intramuscular injection. 2. High urinary concentrations were observed up to 6 hours after administration, and the urinary recovery rate was approximately 60%. 3. Of a total of 142 cases collected, 117 cases were evaluated. Efficacy rates by diseases were: 100% in pneumonia (30/30), 98.3% in urinary tract infections (59/60), and 92.3% in other infections (skin and soft tissue) (12/13), with an overall efficacy rate of 94.9% (including 77 "excellent" cases). 4. Bacteriological examinations showed high eradication rates with the use of GM; i.e., 80% with Staphylococcus aureus (8/10), 60% with Pseudomonas aeruginosa (3/5), 100% with Haemophilus influenzae (7/7) and 97.8% with Escherichia coli (44/45), achieving an overall eradication rate of 92.4%. In mixed infections, the eradication rate was 85.7% (6/7). 5. No ototoxicity, nephrotoxicity or allergic reactions was observed. Abnormal laboratory findings observed were: GOT elevation in 3.1% of cases, GPT elevation in 3.9%, platelet increase in 1.5% and eosinophil increase in 0.8%, thus an overall rate of the appearance of abnormality was 5.6%. The above results indicate that an intravenous drip infusion of GM is a useful method for treating infections in pediatrics. 相似文献