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131.
McCallion Orla N. M. Taylor Kevin M. G. Thomas Marian Taylor Anthony J. 《Pharmaceutical research》1995,12(11):1682-1688
Purpose. Empirical formulae relate the mean size of primary droplets from jet and ultrasonic nebulizers to a fluid's physicochemical properties. Although the size selective filtering effects of baffling and evaporation may modify the secondary aerosol produced, this research sought to evaluate whether viscosity and surface tension of nebulized fluids influenced the aerosol's size and output characteristics.
Methods. Fluid systems of different surface tension and viscosity (glycerol and propylene glycol solutions [10–50% (v/v)] and a range of silicone fluids [200/0.65 cs– l00cs]) were nebulized in three jet and two ultrasonic nebulizers. Secondary aerosol characteristics were measured with a Malvern 2600C laser diffraction sizer and the nebulization times, residual volumes and percentage outputs were determined.
Results. While the droplet size appeared to be inversely proportional to viscosity for jet nebulizers, it was directly proportional to viscosity for ultrasonic nebulizers. Although fluid systems with lower surface tensions generally produced slightly smaller MMDs, the relationship between surface tension and droplet size was complex. The more viscous fluids required longer nebulization times and were associated with increased residual amounts (lower outputs). The ultrasonic nebulizers did not effectively, and were on occasion unable to, nebulize the more viscous fluids.
Conclusions. It follows that there are cut-off values for viscosity and/or surface tension above or below which ultrasonic devices fail to operate. Moreover, jet nebulizers generated an aerosol with an optimum respirable output from median-viscosity fluids. 相似文献
132.
成组序贯试验的原理和方法 总被引:4,自引:1,他引:3
本文介绍了成组序贯试验的原理和方法。它可用于得到结果较慢(如数周或数月)及在整个试验过程中可分少数几个时间段来重复统计分析试验结果的情况。它既保留了传统序贯方法的优点又避免其局限性。当两种处理间确实存在差异时,它常可较早地得出结论,从而可减少样本量,缩短试验周期。特别在临床试验中它可尽早地使受试者停止接受较差的处理,符合伦理学的要求,同时又正好与临床试验中的期中分析相配合,可望有较大的发展前途。 相似文献
133.
The gravity model, a method for analyzing transportation distribution in transportation engineering, was used to explain patient
trips between ten health service regions in a Japanese prefecture. The OD (Origin-Destination) tables were constructed with
zoning by regions, distinguishing between out- and inpatients. The observed trips were determined from the data of a survey
conducted in 1992 that reported the locations of patient residences and chosen medical facilities.
The base values used in the model calculations were the population size of each region and the road distance between the centers
of regions. Problems of intrazonal trip were avoided by setting a mean intrazonal movement distance.
This model was calibrated by the linear regression method with simultaneous validation by the index of correlation coefficients.
The model was found to accurately simulate the effect of distance on the choice of medical facilities and the differences
between the characteristics of in- and out-patients. The population value in use showed the relation not only with demand
but also the supply of clinical services. It was suggested that the model presented here was useful in the allocation of medical
resources and would help explain the relationship between suppliers and consumers of medical services. 相似文献
134.
In this study a staff planning model for a health service clinic has been developed and validated using an example case of a health service clinic. The primary purpose of this research is to develop a representative staff planning model which balances the cost and benefits of staff task flexibility through crosstraining for a healthcare facility. Additionally, legal requirements for task substitution in the healthcare industry have been considered in the model. 相似文献
135.
研究分散第二相Al2O3的含量及颗粒大小对PEO-NaSCN络合物电导的影响,结果表明:当颗粒度为0.7μm时,电导率比纯PEO-NaSCN提高了一个半数量级。颗粒度较大时,电导率均比纯PEO-NaSCN低,并在wAl2O3=0.25时,存在电导率最大的峰值。 相似文献
136.
银杏叶注射液对实验性大鼠局灶性脑缺血的保护作用 总被引:5,自引:0,他引:5
以行为障碍、脑梗死范围、脑含水量、脑组织病理改变为观察指标,研究银杏叶注射液(GBE)对大鼠大脑中动脉闭塞所致局部脑缺血的防治作用。结果表明,GBE20、40mg/kg静脉注射可显著降低大鼠脑梗死范围和脑含水量,改善行为障碍。脑组织形态学检查显示,GBE40mg/kg组动物脑组织缺血病变较轻。提示GBE对局灶性脑缺血具有保护作用。 相似文献
137.
目的 观察人体内化疗药诱导卵巢癌细胞凋亡及其规律性。方法 采用末端脱氧核苷酰的转移酶方法,对9例卵巢癌腹水患者行腹腔化疗,观察不同时间腹水中卵巢癌细胞凋亡的动态变化,并应用免疫组化法动态检测腹水中肿瘤细胞增殖及Bcl-2,Bax基因表达。结果 发现化疗后,肿瘤细胞凋亡多在化疗后48小时达高峰,与化疗前有显著差异(P〈0.05),至120小时,凋亡逐渐下降,部分病例降至治疗前水平,化疗后腹腔内肿瘤细 相似文献
138.
视力客观检测方法的研究 总被引:4,自引:0,他引:4
目的研究用视觉诱发电位(visualevokedpotential,VEP)作为视力客观检测的可行性。方法对40只视力不等的患眼和50只正常眼,分别记录用不同大小方格(8°、4°、2°、1°、30、15和6)刺激时的VEP波形。结果患眼组和正常组P100振幅及潜时在统计学上有显著性差异。视力与能诱发出波形的最小方格间有明显关系:最小方格为6、15、30和1°,平均视力分别为1.13,0.62,0.18和0.07。视力与P100振幅呈正相关,与潜时呈负相关。结论用诱发出VEP波形的最小方格大小可估计患者的视力范围 相似文献
139.
卵巢恶性中胚叶混合瘤12例临床分析 总被引:6,自引:0,他引:6
目的探讨卵巢恶性中胚叶混合瘤的临床特点、治疗及预后因素。方法对我院1983年~1997年收治的12例卵巢恶性中胚叶混合瘤的临床资料进行回顾性分析。按FIGO分期(1985年),Ⅱ期4例,Ⅲ期6例,Ⅳ期1例,不详1例。组织学分类:同源性8例,异源性4例。12例均接受肿瘤细胞减灭术。术后辅助化疗11例,其中3例又追加盆腔放疗。结果全组平均生存24个月,2,5年生存率分别为33.3%(4/12)和8.3%(1/12)。Ⅱ和Ⅲ期生存2年以上者均为2例,Ⅳ期1例在1年内死亡。同源性8例中,4例生存2年以上,异源性4例均在2年内死亡。综合治疗11例中,5例在1年内死亡。单纯手术1例在6个月内死亡。结论卵巢恶性中胚叶混合瘤恶性度高,预后差。其组织学类型、分期及治疗方法与预后有关,应采用手术与化疗和(或)放疗的综合治疗 相似文献
140.
Neuronal death in the inferior olivary complex (IOC) was studied in control and unilaterally pedunculotomized newborn rats, from postnatal day 1 (P1) to P30, in order to test whether the approximately two-fold increase in available specific targets (i.e. Purkinje cells) that is theoretically provided by sectioning one inferior cerebellar peduncle to the developing climbing fibres of the remaining IOC could prevent the loss of inferior olivary neurons taking place during the first 2 weeks of postnatal life in the rat. Numerical estimation of the number of inferior olivary neurons in control and experimental rats showed that (i) in pedunculotomized rats, the number of inferior olivary neurons of the remaining inferior olivary complex was always greater than that encountered in control rats, (ii) the consistent decrease in the number of inferior olivary neurons observed in control animals between P2 and P8 was absent in cell counts of the pedunculotomized rats, and (iii) the increase in olivary cell number following the phase of cell decrease was also absent in pedunculotomized rats. It is concluded that the increase of available Purkinje cells during early postnatal development of the olivocerebellar projection prevents neuronal death in the remaining inferior olivary complex following pedunculotomy. 相似文献