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171.
Ajit K. Shah Richard C. Brundage Kathleen D. Lake Ronald J. Sawchuk 《Biopharmaceutics & drug disposition》1995,16(1):59-70
We estimated the free fraction (fu) of cyclosporine (CyA) in the plasma from concentrations of CyA in urine (Cu) and plasma (Cp), urine flow rate (UF), and glomerular filtration rate in rabbits and in heart transplant patients. Following intravenous administration of CyA (5–30 mg kg?1) in ten NZW rabbits and oral administration of CyA (4.8–12.1 mg kg?1) in nine heart transplant patients, CyA concentrations in urine and plasma were measured by HPLC. The ratios of Cu to Cp and UF data were fitted to a physiological model of renal clearance using NONMEM. The free fraction of cyclosporine in the rabbits and the heart transplant patients was 0.0122 and 0.14, respectively. Because of the relatively low permeability of CyA across the tubular epithelium, no apparent equilibrium between Cu and Cp at any urine flow rate was reached and, therefore, the Cu to Cp ratio will not be equal to fu. 相似文献
172.
用K.S熵(一种信息熵)判别林业系统中生态和经济的协调关系,并提出了控制和改进现有林业系统的有效途径。 相似文献
173.
The Na+–Ca2+ exchange (NCX) system plays a pivotal role in regulating intracellular Ca2+ concentration in cardiomyocytes, neuronal cells, kidney and a variety of other cells. It performs a particularly important function in regulating cardiac contractility and electrical activity. One of the leading NCX inhibitors is KB‐R9743 (KBR) that appears to exhibit selectivity for Ca2+‐influx‐mode NCX activity (reverse mode of NCX). In this article we reviewed pharmacology of KBR and provide a brief summary of studies with other NCX inhibitors, such as SEA0400 (SEA) and SN‐6 (SN). Potential clinical usefulness of KBR and other NCX inhibitors is still controversial but the reviewed findings may be helpful in designing more selective and clinically useful NCX inhibitors for the treatment of cardiac, neuronal and kidney diseases. 相似文献
174.
Chinori Kurata MD PhD Sakae Shouda MD Tadashi Mikami MD Yasushi Wakabayashi MD Tomoyasu Nakano MD Tsuyoshi Sugiyama MD Kei Tawarahara MD PhD Kazuyuki Sakata MD PhD 《Journal of nuclear cardiology》1997,4(6):515
Background. [123I]Metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. We evaluated the clinical significance of myocardial MIBG imaging as a measure of cardiac sympathetic nervous system function by comparing it to heart rate variability and plasma norepinephrine level.Methods and Results. In 211 subjects, we analyzed heart rate variability with 24-hour electrocardiography, performed scintigraphy with MIBG, and measured plasma norepinephrine levels. Time and frequency domain measures of heart rate variability were calculated with the Marquette heart rate variability program (Marquette Electronics, Milwaukee, Wis.). Early and late myocardial MIBG uptakes were measured at 15 and 150 minutes after injection, respectively. MIBG clearance rate from the heart and heart-to-lung and heart-to-mediastinum ratios of MIBG activities were calculated. On the whole, heart rate variability, including low-frequency power, correlated positively, but modestly so, with late MIBG uptake and negatively with MIBG clearance rate. The plasma norepinephrine level correlated negatively with late MIBG uptake and with heart rate variability, including low-frequency power, and positively with MIBG clearance rate. Similar correlations were also observed in patient subgroups with coronary artery disease, diabetes mellitus, and renal failure, but these correlations were weak (R2 < 0.5).Conclusions. Increased cardiac sympathetic nervous system activity may be associated with increased myocardial MIBG clearance and decreased heart rate variability, including low-frequency power. Because these associations were not strong, however, the combination of heart rate variability with MIBG may allow an interactive assessment of the cardiac autonomic nervous system. 相似文献
175.
《实用医技杂志》2004,11(2):185-186
目的 :探讨血管紧张素 (ANG)Ⅱ受体拮抗剂氯沙坦治疗心功能不全中的临床疗效。方法 :选择NHYA心功能分级为ⅡⅣ级、EF≤ 5 0 %的病人 6 8例 ,随机单盲分为氯沙坦和福辛普利组 ,于服药前及服药 6个月观察临床症状、超声心功图。结果 :两组用药后左室射血分数 (EF)、心输出量 (CO)、心脏指数 (CI)及左室舒张末内径等指标均有改善(均为P <0 .0 5 ) ;氯沙坦组血尿酸 (UA)水平降低 (P <0 .0 5 ) ,而对照组无明显变化 (P >0 .0 5 ) ;福辛普利组 4例出现干咳 ,而氯沙坦组无病例出现。结论 :尽管氯沙坦和福辛普利均能改善左心室收缩、舒张功能 ,但氯沙坦可同时降低血尿酸水平 ,且耐受性好。 相似文献
176.
V. Gh. MUSTEATA I. T. CORCIMARU I. A. IACOVLEVA L. Z. MUSTEATA I. S. SUHARSCHII L. T. ANTOCI 《International journal of laboratory hematology》2004,26(6):397-401
The purpose of this comparative study was to evaluate the response of primary splenic low‐grade non‐Hodgkin's lymphomas (NHL) to chemotherapy, splenectomy, and chemotherapy combined with splenectomy in order to elaborate the optimum treatment modality. A total of 104 patients (age range: 15–82 years) with primary low‐grade B‐cell NHL of the spleen were comprised by our study. Stage IV disease was determined in 102 (98.1%) cases. Regarding the treatment modality, splenectomy was performed in 14 patients, early splenectomy and single‐agent chemotherapy in 15, early splenectomy and combined chemotherapy in 19, single‐agent chemotherapy in 23, and combined chemotherapy in 33. In the above‐mentioned order, complete remission rate was following: none, 40.0, 31.6, 21.8, and 18.2%. Partial remissions were achieved in 85.7, 46.7, 57.9, 30.4, and 69.7% of cases, respectively. The median remission duration turned out to be longer (74.5 months) in the group of patients with complete remissions attained by means of splenectomy and combined chemotherapy. Local relapses in the spleen developed in 19 (72.7%) patients treated with combined chemotherapy and in 9 (90.0%), who had undergone single‐agent chemotherapy. The 5‐year overall survival was 54.4% after splenectomy, 39.4% after single‐agent chemotherapy, and 37.1% after combined chemotherapy, being significantly higher (P < 0.05) after splenectomy and single‐agent chemotherapy (67.2%), and splenectomy followed by combined chemotherapy (64.7%). Early splenectomy combined with chemotherapy is the optimum treatment option for primary low‐grade NHL of the spleen because of the superiority in complete remission rate, remission duration, and in overall survival rate. Splenectomy leads to somatic compensation of patients, makes impossible local relapsing in the spleen, prevents continuous dissemination from the primary tumor site, and mostly corrects cytopenias, creating better conditions for chemotherapy. 相似文献
177.
血压变异与心率变异及心电异常相关性分析 总被引:1,自引:0,他引:1
目的:研究血压变异(BPV)与心率变异(HRV)及心电图(ECG)异常相关性,方法:对157例未经治疗的早期高血压患者及167例未服过影响血压及心率药物的正常人,进行BPV、HRV及ECG异常的相关分析,各种数据在同一时刻得到,结果:当血压昼夜节律消失(非杓型),BPV及HRV不正常,ECG异常明显高于其他组,当高血压患者血压昼夜节律存在时HRV各项指标接近正常,ECG异常率较低,HRV降低与血压负荷升高呈明显正相关,与心电异常也呈明显正相关,结论:对高血压治疗的目的。不仅仅是降压,还应尽量恢复昼夜血压的规律性,降低夜间血压负荷,调节植物神经功能,对于血压正常的患者。血压昼夜节律消失也应投以关照给予植物神经功能调节,达到或降低靶器官损伤或延缓靶器官损害的目的,提高患者的生活质量。 相似文献
178.
赵毅 《中国医疗器械杂志》2005,29(6):456-457
来用锁相环IC CD4046设计的心率显示报警电路,用于数台老式监护仪的改造中,获得成功. 相似文献
179.
微量注射大豆皂甙(Ts)到下丘脑后核(PHN)能引起平均动脉压(MAP)升高,心率加快,其效应与向PHN内注入神经肽Y(NPY)相似。分别注入不能引起血压、心率发生明显变化的微量Ts、NPY,如果合并注入PHN则可引起血压、心率的显著变化,表明二者互有加强作用。Atropine可以对抗Ts、NPY或Ts+NPY同时注入PHN的升压效应,提示NPY是通过激活脑内M受体而实现升压效应的,而Ts的心血管效应又可能是经过脑内NPY介导和加强的。 相似文献
180.
Jan Sollenberg Rasmus Bjurström Kent Wrangskog Olof Vesterberg 《International archives of occupational and environmental health》1988,60(5):365-370
Summary Styrene exposure of 18 workers in fiber-glass reinforced plastic industries was measured for 30-min periods throughout each workday for a week. The styrene uptake was estimated using pulmonary ventilation measurements. All urine voidings were collected separately and the styrene metabolites, mandelic acid (MA) and phenylglyoxylic acid (PGA) were determined. The relationship between both exposure and uptake versus excretion of these metabolites was studied. Styrene metabolite concentrations and excretion rates (with 95% tolerance limits) were calculated to correspond to a constant 8-h exposure at the Swedish exposure limit level (25 ppm) or an uptake of an exposure limit related styrene dose (6.3 mmol). The tightest tolerance limits were obtained for excretion rate of MA + PGA per 24 h. The calculated biological exposure limit was 3.4 (± 0.7) mmol MA + PGA/24 h for a dose of 6.3 mmol styrene. 相似文献