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21.
孙伟 《医用生物力学》2005,20(4):247-255
计算机辅助组织工程(CATE)可以帮助进行复杂组织支架的建模,设计和制造,使很多用于改善替代材料力学及生物学性能的新方法得以实施。CATE通过获取组织的生物学、生物力学及生物化学信息,进行界面的设计、模拟和组织的制作。本文将讲述CATE在骨组织工程支架仿生设计中的应用:介绍运用CATE进行仿生建模,解剖结构重建,组织支架设计,定量CT分析,有限元分析和支架的自由挤压沉积制作。  相似文献   
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Several requirements of psychotherapeutic intervention (PI) research are presented. Some major problems are discussed. First, confidence in experimental results may be diminished by interference of possible confounders. A large number of these exist, both physical, perhaps more easily measurable, and psychological or psychosocial. Second, the value and limitations of randomization are presented, with special reference to small N. Validity and reliability are addressed, with emphasis on things that may dilute the strength of both of these measures. Natural remedies are proposed. Internal consistency and reliability are compared and cautions are given regarding their use and possible invalid substitution of consistency for reliability. Comparison of different PIs is commented on, with some relevant examples. Finally, a matter of special interest is discussed: the inconsistency between Spiegel's control survival curve and that produced from local population normative data.Presented at the Symposium Psychotherapeutic Interventions in Cancer Patients, Flims, Switzerland, 12–14 January 1995  相似文献   
24.
Malaria vaccines     
Significant progress has been made in the development of the malaria vaccine during the last 20 years. Ninety percent of the 300–500 million clinical cases of malaria per year worldwide occur in Africa. Thus, research must be directed toward the 1 million African children under 5 years of age who die every year of malaria. An asexual blood-stage vaccine, capable of reducing severe and complicated malaria and malaria-related mortality, is therefore an important public health tool in these countries. Although knowledge of the parasite's biology is incomplete, research has allowed insight into some of the mechanisms that the parasite uses to evade host immunity. This is the basis for adopting an antigenic cocktail approach toward obtaining a synthetic or recombinant subunit vaccine such as the synthetic Colombian Malaria vaccine SPf 66. During the development of Spf66, field trials under both low and high malaria endemicity areas in Latin America and Africa have been carried out. The results from these studies showed a protective efficacy ranging between 38.8 and 60.2% againstPlasmodium falciparum malaria. Given the characteristics of the normal immune response to malaria (relatively short-lived and not completely effective), it is understandable that the main goal is to try to increase the host's natural immunity. The best candidates for designing a malaria vaccine are the proteins required for parasite survival, those with low mutation rates and conserved epitopes. Because these proteins play an important role in multiple or alternative steps during the invasion process, they should be the targets against which a protective immune response should be elicited. The interaction between the malaria parasite and its host is complex. It is therefore crucial to define new ways of improving the immune response—such as directly modifying the chemical structure of epitopes or using new adjuvants or DNA immunization techniques—to produce novel vaccines against this disease.  相似文献   
25.
Summary In a double-blind, placebo-controlled, incomplete cross-over study the bronchodilator, cardiovascular, respiratory and metabolic effects of 3 different oral doses of clenbuterol were studied in 12 patients suffering from partly reversible airways obstruction due to chronic bronchitis. The ventilatory response to oral clenbuterol or placebo was assessed by measurement of specific airway resistance (sRaw) to detect changes in central airways, and of flow at 85% of vital capacity ( 85% VC) to detect change in peripheral airways. Clenbuterol 20, 30 and 40 µg produced a significant decrease in sRaw between 15 and 480 min after administration. Its effect on the large airways was not related to the dose. Clenbuterol 30 and 40 µg caused a significant increase in 85% VC between 60 and 480 min after administration. After 20 µg a significant improvement in 85% VC was found between 120 and 240 min. The over-all effect of 30 µg on the small airways was significantly more pronounced than that of 20 µg and was more sustained than that of 40 µg 120 min after administration. No significant changes in heart rate, ECG or blood pressure were noted. Decreases in PaO2 and O2-saturation after clenbuterol were not related to dose. Slight falls in PaO2 and O2-saturation were also observed after placebo. These observations are briefly discussed. There was negligible lipid mobilization after either the placebo or bronchodilator. A slight but insignificant rise in blood glucose was observed after both 30 and 40 µg of clenbuterol.  相似文献   
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正交设计在固天泉胶囊处方研究中的应用   总被引:2,自引:0,他引:2  
汤道权  刘晓  赵卫 《中药材》2003,26(12):884-886
目的:研究固天泉胶囊处方的最佳组成。方法:用正交试验法考察处方抗利尿作用和镇静催眠作用。结果:优选出最佳处方为原处方。结论:正交设计可以用于中医处方的研究。  相似文献   
28.
目的 研究并改进儿童益智口服液中海参水解工艺。方法 采用 5因素 4水平L16(45)正交试验法 ,以水解度为考察指标 ,对影响水解的因素进行研究。结果 影响海参水解的主次因素为B >A >D >C。优选的水解工艺条件为 :加酶量 (A)1.5 %、加水量 (B) 2 0倍、水解时间 (C) 6h、水解温度 (D) 5 0℃。按此优选工艺生产 ,水解度达 (2 9.2± 0 .9) % (n =3) ,与原工艺所得水解度经t检验比较 ,有极显著差异 (P <0 .0 0 1)。结论 上述结果为儿童益智口服液中海参水解工艺的改进提供了依据  相似文献   
29.
中医研究的三个重要趋势   总被引:11,自引:0,他引:11  
就科学理念对实验设计的指导作用而言,当前中医研究有三个重要趋势:1.从线性的简单系统走向开放的复杂巨系统;2.由模式生物走向人体实验;3.由“纯粹”科学走向与人文科学相融合。  相似文献   
30.
精制芎归缓释滴丸的制备   总被引:11,自引:0,他引:11  
目的:筛选水溶性和水不溶性载体的种类、配比,研究缓释滴丸剂的成型处方。方法:以圆整度、硬度、料液的黏度、流动性、易滴制程度、累计释放百分数等为考察指标,采用正交设计试验对精制芎归缓释滴丸的成型处方进行优选。结果与结论:按照选定的处方既能有一定的速释量,还能保证10h持续释药80%以上,达到了释药设计目的。  相似文献   
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