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《Journal of the American College of Surgeons》2020,230(4):363-370
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3.
目的:对6个厂家不同氢溴酸右美沙芬口服固体制剂进行体外溶出度考察,比较体外溶出情况,为临床用药提供参考。方法:采用转篮法,转速100 r·min-1,用高效液相色谱法测定氢溴酸右美沙芬口服固体制剂在0.1 mol·L-1盐酸溶液中的溶出曲线;以威布尔方程拟合溶出参数T50、Td、m,并对参数进行方差分析。结果:氢溴酸右美沙普通片、分散片、胶囊以及软胶囊的平均累积溶出度分别为94.3%、101.3%、105.2%、93.4%。溶出参数T50、Td差异较大,其中T50最大的是最小的13.4倍。结论:氢溴酸右美沙片、分散片、胶囊以及软胶囊体外溶出行为差别大,产品质量存在较大差异。 相似文献
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Calcified tissue is a common component of atherosclerotic plaques, and occurs most often in mature plaques. The process of calcification is a poorly understood risk factor that may contribute to a plaque's vulnerability to sudden rupture. In this study a solid-state imaging sequence, termed single-point imaging (SPI), was used to observe calcification directly in ex vivo atherosclerotic plaques. Standards were used to validate the ability of (31)P SPI to detect and differentiate calcification from crystalline cholesterol, phospholipids, and other plaque components. After suitable experimental parameters were found, human carotid specimens obtained by endarterectomy were imaged ex vivo by (31)P solid-state imaging and standard (1)H methods. In contrast to (1)H imaging methods, (31)P imaging detected only the calcification in the plaque. 相似文献
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沙利度胺治疗肝癌的实验研究 总被引:1,自引:0,他引:1
目的研究沙利度胺对肝癌的治疗作用。方法采用小鼠肝癌移植性模型。观察沙利度胺对实体型和腹水型肿瘤的治疗作用。结果沙利度胺按每日200mg/kg连续给药10d,能明显抑制肝癌实体型肿瘤的生长,不降低小鼠血细胞数及淋巴细胞增殖;对腹水型肿瘤小鼠虽无明显生命延长作用,但沙利度胺与阿霉素联合用药对肝癌实体型及腹水型均有协调抗肿瘤作用,且可阻止阿霉素造成的小鼠血细胞减少、免疫功能降低。沙利度胺日剂量200mg/kg能明显增加肿瘤组织坏死,促进肿瘤组织边缘淋巴细胞侵润。结论沙利度胺对小鼠肝癌有确切治疗作用,与阿霉素联合用药效果更好。 相似文献
6.
R.A. Fisher 《Transplant infectious disease》2009,11(3):195-202
Abstract: As the most prevalent pathogen among transplant patients, cytomegalovirus (CMV) affects up to three-quarters of all solid organ transplant recipients. While we have made great strides in preventing CMV infection and disease in the early post-transplant period, late CMV infection and indirect effects due to viral immunomodulation remain problematic. Changing immunosuppression practices, including the increasing use of T-cell depleting induction antibodies, have the potential to affect the risk for CMV infection and disease, even in the face of good prophylactic and preemptive therapy. The purpose of this review article is to discuss the impact of CMV infection on long-term allograft outcomes and to re-evaluate the risks and management strategies for prevention of CMV in the framework of evolving modern immunosuppressive strategies. 相似文献
7.
[目的]应用固体滴定技术监测羟基磷灰石(Hydroxyaptite,HA)的溶解平衡过程,观察组织液生理浓度CO2对羟基磷灰石溶解度的影响.[方法]在恒温水浴系统中以HA为固体滴定物.测试液为KCl溶液(0.1 mol/L),并引入恒定分压的CO2(占空气体积比为3.5%±0.1%).半导体二极管激光为发射光源,散射光源探测器用于监测HA的溶解平衡过程并判断超越溶解平衡点所出现的沉淀(合共17次滴定终点).固体滴定总量用于代表溶解度等温线上的数据点.[结果]引入恒定分压CO2后测定的HA在KCl溶液中的溶解度高于其在KCl溶液中所得50倍以上.[结论]固体滴定技术利于监测HA的溶解平衡过程.溶液体系中CO2增加HA的溶解度.推测该现象与CO2-3形成的复合物密切相关. 相似文献
8.
Mathematical modelling of the spatio-temporal response of cytotoxic T-lymphocytes to a solid tumour.
Anastasios Matzavinos Mark A J Chaplain Vladimir A Kuznetsov 《Mathematical medicine and biology》2004,21(1):1-34
In this paper a mathematical model describing the growth of a solid tumour in the presence of an immune system response is presented. In particular, attention is focused upon the attack of tumour cells by so-called tumour-infiltrating cytotoxic lymphocytes (TICLs), in a small, multicellular tumour, without necrosis and at some stage prior to (tumour-induced) angiogenesis. At this stage the immune cells and the tumour cells are considered to be in a state of dynamic equilibrium--cancer dormancy--a phenomenon which has been observed in primary tumours, micrometastases and residual disease after ablation of the primary tumour. Nonetheless, the precise biochemical and cellular mechanisms by which TICLs control cancer dormancy are still poorly understood from a biological and immunological point of view. Therefore we focus on the analysis of the spatio-temporal dynamics of tumour cells, immune cells and chemokines in an immunogenic tumour. The lymphocytes are assumed to migrate into the growing solid tumour and interact with the tumour cells in such a way that lymphocyte-tumour cell complexes are formed. These complexes result in either the death of the tumour cells (the normal situation) or the inactivation (sometimes even the death) of the lymphocytes. The migration of the TICLs is determined by a combination of random motility and chemotaxis in response to the presence of chemokines. The resulting system of four nonlinear partial differential equations (TICLs, tumour cells, complexes and chemokines) is analysed and numerical simulations are presented. We consider two different tumour geometries--multi-layered cell growth and multi-cellular spheroid growth. The numerical simulations demonstrate the existence of cell distributions that are quasi-stationary in time and heterogeneous in space. A linear stability analysis of the underlying (spatially homogeneous) ordinary differential equation (ODE) kinetics coupled with a numerical investigation of the ODE system reveals the existence of a stable limit cycle. This is verified further when a subsequent bifurcation analysis is undertaken using a numerical continuation package. These results then explain the complex heterogeneous spatio-temporal dynamics observed in the partial differential equation (PDE) system. Our approach may lead to a deeper understanding of the phenomenon of cancer dormancy and may be helpful in the future development of more effective anti-cancer vaccines. 相似文献
9.
本文通过酯交换反应合成了一系列脂肪族聚丁二酸酯,对他们的结构和性能作了表征。发现聚酯存在多晶现象,其熔点有奇偶性变化规律。探索了由此系列聚酯与高氯酸锂形成的固体电解质的结构和离子导电性。无机盐的加入提高了电解质的玻璃化温度但降低了聚酯的熔点及结晶度。聚酯电解质的晶体类似于聚酯,其无机盐主要溶解于聚酯的无定形区域。聚酯系列电解质的导电率也有偶奇效应,与熔点变化相反;熔点高的电解质导电率低,熔点低的电解质导电率高。电解质的导电率随温度改变而变化,在室温下电解质的导电率可达10~(-6)s/cm。高分子链上侧基的引入将大大降低电解质的导电性。 相似文献
10.
d-宁烯、丹参及姜黄素衍生物对ras基因产物膜结合和细胞间隙信息传导的影响 总被引:3,自引:0,他引:3
目的旨在寻找新型抗肿瘤药物,进一步研究d-宁烯、丹参及姜黄素衍生物的抗肿瘤机理。采用分子生物学方法及划痕标记染料示踪技术,研究了4种人实体瘤起源的细胞系的细胞间隙信息传导(GJIC)、H-ras癌基因表达以及ras癌基因产物(P21ras蛋白)表达状态,并观察了4种天然产物对它们的影响。结果表明,细胞内染料传输功能的丧失与ras基因突变率呈正相关;单萜化合物d-宁烯和酚类化合物丹参衍生物的抗肿瘤作用可能与抑制P21ras蛋白膜结合和增强细胞间隙信息传导功能有关。提示Ras癌基因产物P21ras蛋白膜结合的抑制与细胞间隙信息传导功能的增强有直接关系。 相似文献