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41.
Even though entirely digitized microscopic tissue sections (whole slide images, WSIs) are increasingly being used in histopathology diagnostics, little data is still available on the effect of this technique on pathologists' reading time. This study aimed to compare the time required to perform the microscopic assessment by pathologists between a conventional workflow (an optical microscope) and digitized WSIs. WSI was used in primary diagnostics at the Laboratory for Pathology Eastern Netherlands for several years (LabPON, Hengelo, The Netherlands). Cases were read either in a traditional workflow, with the pathologist recording the time required for diagnostics and reporting, or entirely digitally. Reading times were extracted from image management system log files, and the digitized workflow was fully integrated into the laboratory information system. The digital workflow saved time in the majority of case categories, with prostate biopsies saving the most (68% time gain). Taking into account case distribution, the digital workflow produced an average gain of 12.3%. Using WSI instead of conventional microscopy significantly reduces pathologists' reading times. Pathologists must work in a fully integrated environment to fully reap the benefits of a digital workflow.  相似文献   
42.
对贫困人口实施医疗救助   总被引:26,自引:5,他引:21  
本文在分析了我国城乡居民收入分配中的公平性加重、医疗保障水平降低、医疗费用大幅度上涨、个人负担比例增加和卫生保健等筹资的“供方投入”模式的不合理性以及贫困人口较差的健康状况和卫生服务利用水平、贫困人口的主要健康问题、“需方投入”模式对供方的激励作用的基础上,认为对贫困人口实施医疗救助不仅符合公平原则,而且符合效率原则。医疗救助计划应该成为我国目前正在步步深入的卫生改革的重要组成部分。作者分别以我国  相似文献   
43.
In this paper we use nonparametric mathematical programming models to compute and decompose Malmquist indices of productivity and quality change, which are used to evaluate the reforms in the UK National Health Service in the early nineties. We focus on acute hospitals and we study them over the first five years of the reforms. The findings of the study indicate that there was a productivity slowdown in the first year after the reforms but productivity progress in the subsequent years and thus, overall there was a net gain in productivity over the entire period considered. Productivity trends were dominated by technical change rather than hospital relative efficiency changes, as hospitals were already largely relatively efficient at the time of the introduction of the reforms. In fact, over the last four years in the period studied there was small relative efficiency regress and this does not bear out the argument that the reforms would increase hospital efficiency. The productivity changes are similar when service quality is incorporated in the analysis but the magnitude of these changes diminishes. Quality of service followed different trends to productivity change and this may have been the price for the productivity gains achieved.  相似文献   
44.
针对清远市人民医院的经验是否具有普遍意义,能否在全国推广的疑问,论述了“优质高效低耗”模式的特点及内涵,阐述了建立“优质高效低耗”模式的理论基础及政策依据。指出,推行“优质高效低耗”模式必须进行管理体制的改革,其中转变政府职能,放权给医院尤为重要。  相似文献   
45.
46.
There are no published data for the activity of technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) found 1in breast milk. The amount of radioactivity in breast milk following the administration of 500 MBq99mTc-HMPAO for a brain perfusion study has been measured. The effective dose to the infant was calculated to be 0.26 mSv, so necessitating no interruption of breast feeding. Unbound99mTc is readily secreted into breast milk and the effective dose will remain less than 1 mSv if the99mTc-HMPAO labelling effici ency is 99% for the worse reported case, and could remain <1 mSv for the mean reported case for99mTc-HMPAO labelling efficiencies down to 94%.  相似文献   
47.
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities.  相似文献   
48.
胰岛素壳聚糖纳米粒的制备   总被引:10,自引:2,他引:10       下载免费PDF全文
 目的制备胰岛素壳聚糖纳米粒。方法采用酶水解和超滤膜分离技术,得到不同相对分子质量的壳聚糖,由凝胶渗透色谱法测定其相对分子质量;采用溶剂扩散法制备纳米粒,研究纳米粒的空间结构,测定其粒径、表面电位(zeta电位)、模型药物胰岛素包封率及体外释放。结果通过控制酶水解条件,经超滤分离得到3种不同相对分子质量的壳聚糖,凝胶渗透色谱法测得的重均相对分子质量(MW)分别为10 289,41500和101 870。经溶剂扩散法制备得到的壳聚糖纳米粒,呈类圆形球体,粒径分布较窄,且随制备工艺中乙醇加入量的增加、分散用超声次数的增多,以及壳聚糖分子量的降低,粒径变小。壳聚糖纳米粒带正电荷,zeta电位值大于+30 mV。放射免疫法测得的药物包封率为72.66%。在壳聚糖酶存在条件下,前1 h体外释放药物较快,1 h后趋于平稳,并能持续释放6 h。结论选用合适相对分子质量壳聚糖制备胰岛素壳聚糖纳米粒,方法简便,药物包封率高,并有一定的缓释作用。  相似文献   
49.
生物合成调控的青霉素发酵数学模型与过程优化   总被引:4,自引:0,他引:4  
青霉素生物合成受溶解氧、溶解二氧化碳、pH、氨氮、碳源(特别是葡萄糖)等的调控,这些调控反应的产生不仅与基础培养基配方有关,更受发酵过程通气、搅拌条件及补料方案的影响。为此,笔者通过把握发酵过程中产生菌生长和青霉素生物合成代谢流的元素平衡、能量平衡以及传递与反应速度平衡的方法,结合生产经验和数据资料,建立了一种能够模拟青霉素发酵过程工艺学参数和经济学参数变化的数学模型。应用这一模型,在充分考虑生物合成代谢调控的基础上,对青霉素发酵过程进行优化,即通过补水维持上述平衡,避免因环境条件、初始条件和约束条件的变化及人为的失误造成的过程波动,使生产不断趋向最优状态。模拟运行表明,这种优化可显著提高发酵生产的经济效益。  相似文献   
50.
灯盏花素纳米脂质体包封率测定方法研究   总被引:19,自引:1,他引:19  
熊非  朱家壁  王维  华小兵 《药学学报》2004,39(9):755-757
灯盏花素(breviscapine)是菊科植物短葶飞蓬(Erigeron breviscapus(vant.)Hand-Mazz)中提取的黄酮类有效成分。临床多用于治疗脑梗死、脑血栓、脑出血等。将药物制成脂质体,能帮助药物进入脑部,提高治疗指数。灯盏花素水溶性较差,直接溶于注射用水有一定困难,将其制成脂质体可以解决其难溶问题,提高药物稳定性及载药量,同时提高药物的靶向性及疗效。包封率是脂质体质量评定的重要指标,本实验建立了灯盏花素纳米脂质体包封率的测定方法,该法操作简单、可行、准确性较好。  相似文献   
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