State and output feedback design for robust tracking of linear systems with rate limited actuators

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.     

异丙酚静脉全麻复合硬膜外腔阻滞麻醉期间CO2气腹对血流动力学和氧耗的影响

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.     

人肿瘤特异抗原MAGE-3基因疫苗的构建和表达

目的：克隆肿瘤特异性共享抗原mage-3基因，制备基于α－病毒复制酶的高效黑色素瘤特异性基因疫苗。方法：用RT-PCR方法从黑色素瘤细胞系LB373中制备mage-3基因，以含α－病毒复制酶的哺乳细胞高效表达质粒pSMART2a为载体，构建重组DNA疫苗。重组子用载体中的T7和T3启动子序列为测序引物进行自动测序。再将鉴定过的重组质粒用脂质体法转化293细胞，用免疫印迹法和免疫组化法鉴定转化细胞中mage-3蛋白的表达。结果：正确构建了mage-3/pSMART2a重组质粒，并且在转化此质粒的293细胞中检测出了mage-3蛋白的表达。结论：此重组mage-3/pSMART2a质粒可以作为肿瘤特异的DNA疫苗，可进行下一步的肿瘤动物模型的疫苗接种及相关免疫学效应研究。     

Wall-eyed bilateral internuclear ophthalmoplegia from lesions at different levels in the brainstem.

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.     

静脉药物配制中心安全管理实践

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。     

Preparation and characterization of intelligent core-shell nanoparticles based on poly(D,L-lactide)-g-poly(N-isopropyl acrylamide-co-methacrylic acid).

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.     

Laparoscopic Local Resection Based on Sentinel Node Evaluation for Early Gastric Cancer: A Preliminary Report

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.     

血清高水平甲状旁腺激素-非透析慢性肾脏疾病患者的隐形杀手

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.     

1例系统性红斑狼疮患者视网膜中央动脉阻塞及脑出血的护理

对1例系统性红斑狼疮并发视网膜中央动脉阻塞及脑出血患者，给予糖皮质激素、免疫抑制剂、高压氧、改善微循环及对症支持治疗．同时予以密切观察病情、药物护理、高压氧治疗护理及健康教育等措施，结果患者恢复良好出院。提出该病虽然少见且后果严重，但及时采取综合性治疗护理措施，可以提高治疗效果。