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201.
E. A. von Reth M. J. F. P. Pluym A. A. van Steenhoven J. Poulis A. Versprille 《Medical & biological engineering & computing》1987,25(1):51-56
The indicator-dilution technique is commonly used to determine mean flow estimates. The estimation of instantaneous flow from
the shape of an indicator-dilution curve is the objective of this study. Based on a mixing chamber approach to the flow system,
a mathematical relationship is derived to reconstruct momentary flow from an indicator-dilution curve. This relationship is
verified in a model setup both with only constant flow and with a sinusoidal flow variation superimposed. This method proved
to give good flow estimates for limited values of flow parameters. Also, some preliminary experiments were performed in a
pulsating flow system simulating heart action. The results were promising although the method proved to be very sensitive
to baseline offset. 相似文献
202.
203.
论公费医疗大额死亡病例的资源消耗与医学目的 总被引:4,自引:2,他引:2
从北京市公费医疗大额消耗的92例死亡病例的费用结构及住院城数的统计,提示由住院日地长,贵重卫生资源的盲目过量投入等而致。这与中国国情不符。因此,医学目的概念应更新,以及应如何正确对待死亡病例的医疗服务值得进行讨论。 相似文献
204.
A. M. Wilson K. Haggart E. J. Sims B. J. Lipworth 《Clinical and experimental allergy》2002,32(10):1504-1509
BACKGROUND: In vitro studies have shown much higher H1-receptor antagonist potency with desloratadine (DL) compared to fexofenadine (FEX), although it is unclear whether this has any clinical relevance on disease control parameters in seasonal allergic rhinitis (SAR), especially for nasal congestion. OBJECTIVE: To compare the relative efficacy between presently recommended doses of DL and FEX on daily measurements of peak nasal inspiratory flow (PNIF) and nasal symptoms in SAR. METHODS: Forty-nine patients with SAR were randomized into a double-blind, placebo-controlled cross-over study during the grass pollen season, comparing 2 weeks of once daily treatment with (a) 180 mg FEX or (b) 5 mg DL, taken in the morning. There was a 7-10 day placebo run-in and washout prior to each randomized treatment. Measurements were made in the morning (AM) and in the evening (PM) for PNIF (the primary outcome variable), nasal and eye symptoms. The average of AM/PM values were used for analysis. RESULTS: There were significant (P < 0.05) improvements, compared to placebo, with FEX and DL, for PNIF, nasal blockage, nasal irritation, and total nasal symptoms, but not nasal discharge or eye symptoms. There were no significant differences between active treatments. Values for PNIF (L/min) for mean placebo baseline, mean difference from baseline (95% CI for difference) were 126, 10 (4-16) for FEX; and 122, 11 (4-17) for DL. The mean difference (95% CI) between FEX vs. DL was 1 L/min (-7-8). Values for total nasal symptoms (out of 12) were: 3.2, 0.7 (0.2-1.2) for FEX; and 3.4, 0.9 (0.3-1.5) for DL, and for nasal blockage (out of 3) were: 1.1, 0.2 (0.1-0.4) for FEX; and 1.2, 0.3 (0.1-0.5) for DL. The mean difference (95% CI) in total nasal symptoms and nasal blockage between FEX vs. DL was 0.1 (-0.6-0.8) and 0.1 (-0.2-0.3), respectively. CONCLUSIONS: Recommended once daily doses of fexofenadine and desloratadine were equally effective in improving nasal peak flow and nasal symptoms in SAR. 相似文献
205.
应用流式细胞计对30例宫颈腺癌和混合癌细胞的DNA指数和细胞增殖周期各时相细胞分布比例进行分析,结果显示非整倍体肿瘤29例,占96.7%.流式细胞计在诊断恶性肿瘤方面是有价值的。细胞增殖周期比DNA指数对预后的估价更有意义.乳头型腺癌、分化I级的肿瘤,S+G2M比率最低,5年生存率最高. 相似文献
206.
E. B. Andersen F. Boesen O. Henriksen 《Clinical physiology and functional imaging》1991,11(5):451-458
Summary. The effect of age and sex on relative changes in blood flow and vascular resistance in skeletal muscle and subcutaneous tissue during postural changes and during local increase in transmural pressure was studied in 33 healthy subjects. The intra-individual variation was studied in five subjects. Blood flow was measured by the local 133Xenon wash-out method. No relation to age or sex was seen in the centrally elicited sympathetic vasoconstrictor responses in subcutaneous tissue and skeletal muscle and in the locally elicited vasoconstriction in subcutaneous tissue. A small, but statistically significant, correlation to sex and age was found in the local sympathetic vasoconstrictor response in skeletal muscle. The age correlation was caused only by an attenuated response in the young subjects below 40 years of age and may be fortuitous. The intra-individual variation was acceptably small. Based on the present results, a reduction in blood flow in skeletal muscle and subcutaneous tissue during centrally or locally elicited sympathetic vasoconstriction of 10% or less should be considered abnormal. The local 133Xenon wash-out method is of value in examining patients suspected of dysfunction in the sympathetic part of the autonomic nervous system. 相似文献
207.
The aim of this study was to investigate the reactivity of the nasal mucosa of patients with pollen allergy compared to healthy controls, when challenged with histamine outside the pollen season. Assessments were made with symptom score, acoustic rhinometry, nasal peak expiratory and inspiratory flow (NPEF and NPIF) and rhinomanometry in order to find the most sensitive method for the purpose. Twenty-one patients with seasonal allergic rhinitis and 20 healthy controls were challenged with histamine dihydrochloride in increasing concentrations (0.01, 0.1, 1.0 mg/ml) locally in the nose. Our results show no difference in mucosal reactivity between the patients and controls regardless of the method used. When comparing the methods we find that NPIF and NPEF are more sensitive to mucosal changes than the other methods we have studied. 相似文献
208.
Summary This study evaluates local variations of the cerebral vasomotor responses to hypercapnia and haemorrhagic hypotension in a pig model. Four laser Doppler flow probes were used in each pig. There was considerable variation in laser Doppler signals between the four probes in baseline recordings. The increases in flow after CO2 administration in 7 pigs had a mean coefficient of variation of 0.43 ± 0.31, and the flow changes after blood loss in another 7 pigs had a mean coefficient of variation of 0.45 ± 0.34. The range of flow changes within each animal was large; the probe with the highest CO2 response showed on the average a 273% ± 157% larger CO2 response than the probe with the lowest CO2 response. Correspondingly, the probe with the best preserved blood flow after blood loss had on the average a flow value of 93% ± 12% of the baseline value, while the probe that changed most with haemorrhage had a flow value of 44% ± 24% of the baseline value. Single laser Doppler recordings have been used for the monitoring of cerebral blood flow in neurosurgical critical care, but our results suggest that a single laser Doppler flow probe is not an adequate method to monitor vasoreactivity in neurosurgical patients because flow signals from one probe may be unrepresentative for other sites in the brain. 相似文献
209.
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
210.
本文应用流式细胞仪对35例肺癌、10例良性病变肺组织及10例正常肺组织的细胞增殖活力(S%)进行了分析,结果显示肺癌组织细胞增殖活力非常显著高于良性病变组,良性病变组细胞增殖活力亦非常显著高于正常组,提示检测细胞增殖活力对肺癌的诊断、筛选有一定意义。 相似文献