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61.
目的:评价变应性哮喘患儿血清嗜酸性粒细胞阳离子蛋白(S-ECP)水平改变及其意义。方法:测定25例哮喘发作期患儿糖皮质激素吸入治疗12周前后,及20例未予糖皮质激素吸入治疗的哮喘缓解期患儿S-ECP水平,并对发作期患儿S-ECP水平变化与血嗜酸性粒细胞计数(B-EOS)、肺功能一秒用力呼气量(FEV1)、一秒用力呼气量比用力肺活量(FEV1/FVC)及症状评分的关系作相关性分析。结果:哮喘发作组治疗后S-ECP水平较治疗前显著降低,与对照组(健康儿童10名)比较差异无显著性;哮喘缓解组S-ECP水平明显高于发作组治疗后,但明显低于发作组治疗前。哮喘发作组治疗前S-ECP水平变化与B-EOS无相关性,与FEV1、FEV1/FVC呈负相关,与症状评分呈正相关。结论:监测S-ECP水平可作为评价哮喘气道炎症程度、病情预后和指导抗炎治疗的有效指标。  相似文献   
62.
A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
63.
OBJECTIVE: To investigate the effects of intraperitoneal CO2 insufflation on the hemodynamics, oxygen consumption (VO2) and carbon dioxide production (VCO2) during intravenous anesthesia with propofol in combination with epidural block. METHODS: Intratracheal intubation was performed after rapid induction of anesthesia and mechanical ventilation was given. Maintenance of anesthesia was achieved using continuous intravenous propofol infusion (2 mg/kg/h) ?N2O inhalation and intermittent epidural administration. Indices of hemodynamics and respiratory function were collected 5 min before induction, 1 min before CO2 insufflation, and 5, 10, 20, 30, 40, 50, 60 min after the start of insufflation and 5 min after the termination of insufflation. RESULTS: The mean arterial pressure (MAP), heart rate (HR), end-tidal PCO2 (P(ET)CO2), VO2 and VCO2 1 min before insufflation were markedly reduced(P<0.01), compared with those recorded before induction. MAP and HR did not undergo any conspicuous changes during CO2 insufflation and 5 min after insufflation termination. Compared with that 1 min before insufflation, PETCO2 was significantly increased 20 min after the start of insufflation (P<0.01), and subsequently carried on the increase though of a lesser scale. VO2 and VCO2 gradually rose after the start of insufflation, and VO2 presented a significantly elevation (P<0.01) 10 min after the insufflation while VCO2 did not show this marked increase(P<0.05) till 20 min after the insufflation in comparison with the levels before insufflation. Subsequently, VO2 continued to rise and VCO2 also retained the increase but of smaller magnitude. CONCLUSION: Intravenous propofol anesthesia combined with epidural block assisted by well-managed excessive ventilation before insufflation can alleviate the adverse effects of CO2 insufflation on respiratory and circulatory systems.  相似文献   
64.
对218例女性乳癌术后进行了十年以上的随访观察。随访率为95.87%。术后总的十年生存率为54.87%。Ⅰ期为85.71%,Ⅱ期为53.09%。Ⅲ期为30.76%。阐明了术后疗效与妊娠哺乳,肿瘤部位,肿瘤大小,临床期别,淋巴结转移情况及病理类型有明显关系。讨论了手术方式对术后的影响,提示扩大根治术对Ⅰ、Ⅱ期乳癌并无明显优越性。  相似文献   
65.
Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rarely reported syndrome. There is dispute about whether WEBINO is caused by a pontine or a midbrain lesion and whether the medial rectus subnuclei are implicated. In a study of the clinical and imaging features of four patients with WEBINO, we found that that three of four lesions involved the midbrain but not necessarily the medial rectus subnuclei.  相似文献   
66.
静脉药物配制中心安全管理实践   总被引:1,自引:0,他引:1  
林菊芬  杨素清 《护理研究》2005,19(8):1580-1581
静脉药物配制中心(PIVAS)是为保证病人的输液质量而对输液进行集中管理、集中配制的新形式。它打破了传统的在开放条件下进行药物配制的工作流程,使操作人员在局部百级洁净区严格按照无菌配制技术集中配制药物,可以防止细菌和微粒的污染,为病人提供无菌、安全、高效的药品,并可减少由于输液反应而引发的医疗纠纷;通过购买大包装的药品,可以降低药晶价格、减少药品浪费、降低医疗成本;临床护士用于药品配制的时间大大缩短,提高了护理质量。虽然PIVAS在医院工作中受到欢迎,但由于运行环节较多,且在我院启用的时间不长,还是一项不成熟的服务模式,我们也发现一些尚待提高和解决的问题。针对存在的安全隐患,制订了一系列防范措施,经过半年多的实践,在实施过程中运行良好。现总结如下。  相似文献   
67.
New thermo-responsive, pH-responsive, and biodegradable nanoparticles comprised of poly(D,L-lactide)-graft-poly(N-isopropyl acrylamide-co-methacrylic acid) (PLA-g-P(NIPAm-co-MAA)) were developed by grafting biodegradable poly(D,L-lactide) onto N-isopropyl acrylamide and methacrylic acid. A core-shell type nano-structure was formed with a hydrophilic outer shell and a hydrophobic inner core, which exhibited a phase transition temperature above 37 degrees C suitable for biomedical application. Upon heating above the phase transition temperature, PLA-g-P(NIPAm-co-MAA) nanoparticle showed a polarity increase of pyrene in either buffer solution or intra-hepato-carcinoma cells as determined by fluorescence measurement, indicating that the structure of nanoparticles caused leakages from outer shell copolymers aggregation and collapsed. The drug loading level of 5-fluorouracil (5-FU) encapsulated in the PLA-g-P(NIPAm-co-MAA) nanoparticles can be as high as 20%. The release of 5-FU from nanoparticles was strongly controlled by the pH in the aqueous solution. Based on these results, PLA-g-P(NIPAm-co-MAA) nanoparticles can be used as a drug carrier for intracellular delivery of anti-cancer drug.  相似文献   
68.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
69.
维持性血液透析患者血清甲状旁腺激素(Parathyroid hormone,PTH)水平显著增高,PTH与患者心功能下降、营养状态恶化以及死亡率的增加密切相关.然而,临床实践发现,部分慢性肾脏疾病(Chronic kidney disease,CKD)3-4期、甚至CKD1期的患者血清PTH水平也增高,PTH对此类患者的影响如何,目前报道较为少见.本文结合文献就FTH对非透析CKD患者的心血管系统、骨代谢、营养状况及预后的影响作一综述.  相似文献   
70.
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