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61.
Lasers in Medical Science - After publication of this paper, the authors determined an error in Fig. 1.  相似文献   
62.
脊髓损伤(SCI)会导致患者自主神经功能、运动和感觉功能丧失,对患者的生活质量产生极大影响[1].SCI的病理变化包括损伤部位缺血、缺氧、神经元受损、瘢痕组织形成和炎性反应等[2].近年来, SCI的病理变化机制研究日趋深入,周细胞作为脊髓微环境的重要组成部位,在SCI的病理过程中发挥着重要作用.SCI发生后神经元轴突遭到破坏,这一过程伴随着血-脊髓屏障的破坏,神经胶质细胞和神经元细胞活化,并分泌多种副产物(包括基质金属蛋白酶、游离氧自由基、趋化因子和细胞因子)[3].各种免疫细胞渗入损伤部位[4],受损区域周围还会产生星形胶质细胞,小胶质细胞同样会被激活[5-6].  相似文献   
63.
Using a digital simulation method, we analyzed the relationship between natural frequency (f n ) and damping coefficient () of the catheter-manometer system required for high-fidelity measurement of the pulmonary arterial pressure. The pulmonary artery pressure waveform was obtained with a catheter-tip transducer and it was fed into a dynamic simulator programmed on a computer. The original waveform and the output of the simulator were compared and judged visually for the fidelity. From this analysis, the combination of f n and was obtained and was plotted on a f n diagram. It showed as an area, which was convex on the left side and open on the right side. The left-convex endpoint was located at a damping coefficient of about 0.7. At a lower heart rate, this area was extended to the lower frequency side, while, at a higher heart rate, this area was limited to the higher frequency side. The f n diagram was also constructed theoretically by calculating the relations between natural frequencies and damping coefficients of a second order system with the amplitude and phase error tolerance set at +/–5% respectively.(Kinefuchi Y, Suzuki T, Takiguchi M, et al.: Natural frequency/Damping coefficient relationship of the catheter-manometer system required for high-fidelity measurement of the pulmonary arterial pressure. J Anesth 7: 419--426, 1993)  相似文献   
64.
To evaluate the role of thromboxane A2 (TXA2) in ischemic liver injury, the serum changes in thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-K-PGF1) following warm ischemia of the total canine liver were examined, and the protective effect of a TXA2 synthetase inhibitor was assessed. Total liver ischemia was performed for 60 min on two groups of dogs: a control group, in which ischemia alone was performed, and an OKY-046 group, which received a TXA2 synthetase inhibitor. A temporary active portacaval shunt was used to eliminate the effects of splanchnic venous stasis during clamping of the hepatic pedicle. Postoperative changes in liver function, assessed by the transaminase enzyme levels, and in prostaglandins were recorded and the histologic liver findings of both groups 1 week after ischemia were compared. The levels of 6-K-PGF1 increased after reperfusion in both groups, while those of TXB2 increased in the control group but maintained low levels in the OKY-046 group. Liver function was better and histologic changes less marked in the OKY-046 group than in the control group, suggesting the important role of TXA2 in ischemic liver injury and the usefulness of a TXA2 synthetase inhibitor for protecting the liver against ischemic injury.  相似文献   
65.
We propose a model which combines oxygen transport system from blood to tissue with oxygen utilization system at the tissue.The model consists of 3 equations; the relationship between tissue PO 2 (PtsO 2) and O2 utilization (VrcO 2), diffusion from vessel to tissue, and Fick equation. This model has two advantages. First, it is self-consistent. Varying VrcO 2 varies the oxygen transport. Second, it enables to analyze the effects of various factors of oxygen transport/utilization on other factors.We applied this model to the brain tissue. Following values were assumed. Critical tissue PO 2 (PcritO 2) 2mmHg; oxygen utilization above this level 3ml·min–1·100g–1; diffusion coefficient from blood vessel to tissue (D) 0.2ml·min–1·mmHg–1·100g–1; cerebral blood flow (CBF) 50ml·min–1·100g–1; hemoglobin 15g·100ml–1. Hill equation was used for oxygen dissociation curve with n of 2.7 and P50 of 27.0mmHg.From these, the following values were obtained; PvO 2, PtsO 2 and VrcO 2. The changes were analyzed for the 5 input values, PaO 2, CBF, D, P50 and Hb, changing from zero to their respective normal values. A reduction of a single parameter down to 50% of normal barely affected oxygen utilization. A further reduction resulted in significant oxygen utilization. Under conditions studied, a decrease in P50 reduced oxygen utilization faster than that in any other parameters.(Suwa K: Analysis of oxygen transport and oxygen utilization combined. J Anesth 6: 51–56, 1992)  相似文献   
66.
We programmed a formula which predicts the incidence of either myocardial infarction or cardiac death during the postoperative period. The original formula was proposed by Shah et al, based on their own data and analysis. The program is simple and is written in a language called Quick Basic. The use of this program is also simple. Such a program has improved the use of this analysis substantially. The program has been posted on to a few Computer network services as a free software.(Suwa K, Ogura S: Programming a predictive formula for angina and other risk factors in patients with cardiac diseases undergoing non-cardiac operations. J Anesth 6: 241–242, 1992)  相似文献   
67.
We held a computer software contest at 38th Congress of the JSA, held in March, 1991. The aim is to encourage the members of the Society to write softwares and to help distribute them, especially as Freewares. We received 25 entries for the contest; two-thirds of these are for computers of NEC PC9801 series and a third are for Macintosh. We received donations 3 million yen worth of instruments and goods for prizes plus some cash, which as prizes were distributed to those who made entries for the contest.Most of these programs have been registered as freewares at various computer networks, including our Ether-Net, one of the common computer network SIGBBSs among Japanese anesthesiologists.(Suwa K, Miyasaka K, Tanaka Y, et al.: Report on the computer software contest at 38th congress of the Japan society of anesthesiology. J Anesth 5: 441–444, 1991)Executive Committee of the Computer Software Contest at 38th Congress of the Japan Society of Anesthesiology  相似文献   
68.
Application of potent skin carcinogens, such as 7, 12-dimethylbenz[a]anthracene,3-methylcholanthrene, benzo[a]pyrene and 4-nitroquinoline-1-oxide,induced numerous dihydroxyphenylalanine (dopa)-positive cellsin the interfollicular epidermis of C57BL/6 mice in a dose-and time-dependent fashion. Chrysene, a weak skin carcinogen,and croton oil, a tumor promoter, also induced 3–4 timesmore dopa-positive cells than acetone. Liver carcinogens, suchas 3'-methyl-4-di-methylaminoazobenzene and N-2-acetylaminofluorene,and non-carcinogenic aromatic hydrocarbons, such as anthracene,fluoranthene, fluorene and pyrene, did not induce increase inthese cells. These results indicate that increase in the numberof dopa-positive cells after application of chemicals is wellcorrelated with the abilities of these compounds to induce skincarcino-genesis and suppress sebaceous glands.  相似文献   
69.
The case of an 80-year-old man with plasma cell leukemia characterized by basophilic cytoplasm, and extensive lobulated nuclei is described. In spite of the peculiar morphologic nuclei, the diagnosis was based on the presence of M protein and Bence Jones protein in the serum and urine, immunophenotypic characteristics, immunoglobulin gene rearrangement, and findings of transmission electron microscopy.  相似文献   
70.
目的观察全反式维甲酸(ATRA)联合三氧化二砷(As2O3)治疗急性早幼粒白血病(APL)的疗效和不良反应。方法ATRA20~40mg/d,分2~3次服用;As2O3(0.1%溶液)10mL加入5%葡萄糖溶液500mL中静脉点滴,持续4~6h,1次/天,联合治疗初发APL。根据外周血白细胞计数、肝功能变化适当调整ATRA和As2O3的剂量。观察CR率、获得CR所需的时间、不良反应及近期缓解时间。结果16例初发APL患者早期死亡1例,15例获CR,CR率93.7%,获得CR的平均时间为(25.7±5.2)天。62.5%患者在治疗开始后出现白细胞升高,调整ATRA后均恢复。50%患者出现肝功能异常,经调整剂量及应用保肝药后均坚持应用As2O3至疗程结束。至今15例获CR的患者仍处于CR状态(2~26个月)。结论ATRA联合As2O3治疗初发APL疗效好,不良反应少,而且能缩短达CR的时间。  相似文献   
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