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排序方式: 共有498条查询结果,搜索用时 31 毫秒
1.
膀胱癌组织P-gp,GST-π和TOPO-Ⅱ表达评估灌注化疗 总被引:1,自引:0,他引:1
目的:探讨膀胱癌的多药耐药性(MDR),指导灌注化疗用药。方法:采用免疫组化法检测44例膀胱癌病理标本中P-糖蛋白(P-gp)、谷胱肽S转移酶(GST-π)和拓扑异构酶(TOPO—Ⅱ)的表达,评估肿瘤耐药谱。结果:①P-gp检测显示,54.5%的病例对阿毒索、丝裂毒索、长春新碱等抗生索类和生物碱类抗癌药高耐药。②GST-π检测显示仅34.1%的病例对顺铂、环磷酰胺等高耐药,而反有56.8%的病例对该类药无耐药或低度耐药。③TOPO-Ⅱ检测显示对阿霉索、柔红毒索、VP16等TOPO-Ⅱ抑制剂类抗癌药,仅13.6%的病例高度耐药,29.5%中度耐药。56.8%低度耐药。结论:检测膀胱癌MDR,了解多药耐药谱,可指导灌注化疗用药。 相似文献
2.
The bond strength of porcelain fused to cast and wrought titanium surfaces was calculated from fracture loads in a 4-point bending test. Two different porcelain were applied (O'Hara and Duceratin). The surface of Ti-cast specimens was treated in two different ways to produce variations in the impurity level before porcelain veneering. Microhardness measurements as well as scanning electron microscopy with EDX analysis were conducted. The results showed no significant difference in bond strength between the two porcelains. Nor was any difference in bond capacity found between thoroughly blasted castings and wrought titanium. Significantly lower bond strengths were observed for lightly blasted specimens and for specimens treated with Gold bonding agent. Impurities in the surface region of the castings were found to be due to contact with the investment during solidification. This indicates that a thin surface layer (50-100 microns) of the casting should be removed before firing of the porcelain. 相似文献
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Smeyers YG Herńandez Laguna A Romero-Sánchez FJ Fernández-Ibañez M Galvez-Ruano E Arias-Pérez S 《Journal of pharmaceutical sciences》1987,76(9):753-756
In the present work, the mechanism of action of fosfomycin [(-)-(1R,2S)-(1,2-epoxypropyl)phosphonic acid] as an antibiotic agent is studied by "ab initio" quantum mechanical calculations and by 1H, 13C, and 31P NMR measurements. Attention is focused on the relative charge density and chemical shift of the C(2) atom of the epoxy ring, which seems to be closely related with the activity of this antibiotic. The theoretical results suggest that the sulfhydryl addition should be preceded by a necessary anchoring of the phosphonate moiety on a positive group of the receptor. 相似文献
5.
Anne Sophie Kruit Kaj Brouwers Dominique van Midden Her Zegers Erik Koers Nens van Alfen Stefan Hummelink Dietmar J. O. Ulrich 《Transplant international》2021,34(2):365-375
The current standard for composite tissue preservation is static cold storage (SCS) and is limited to 6 h until irreversible muscle damage occurs. Extracorporeal perfusion (ECP) is a promising technique for prolonged preservation, however, functional results have been scarcely researched. This article assessed neuromuscular function and compared results to histological alterations to predict muscle damage after ECP. Forelimbs of twelve Dutch landrace pigs were amputated and preserved by 4 h SCS at 4–6 °C (n = 6) or 18 h mid-thermic ECP with University of Wisconsin solution (n = 6). Limbs were replanted and observed for 12 h. Sham surgery was performed on contralateral forelimbs (n = 12). Histology analysis scored four subgroups representing different alterations (higher score equals more damage). Muscle contraction after median nerve stimulation was comparable between ECP, SCS, and sham limbs (P = 0.193). Histology scores were higher in ECP limbs compared to SCS limbs (4.8 vs. 1.5, P = 0.013). This was mainly based on more oedema in these limbs. In-vivo muscle contraction was well preserved after 18 h ECP compared to short SCS, although histology seemed inferior in this group. Histology, therefore, did not correlate to muscle function at 12 h after replantation. This leads to the question whether histology or neuromuscular function is the best predictor for transplant success. 相似文献
6.
Thermal analysis of aqueous solutions in which the solute does not crystallize immediately upon freezing was carried out to define the effects of experimental parameters on thermograms in the glass transition region. The intensity of enthalpy relaxations in the glass transition region is related to both the rate of cooling and the rate of heating through the glass transition region—slow cooling or slow heating increases the extent of structural relaxation in the glassy state and increases the intensity of the endotherm. Plots of the logarithm of heating rate versus l /Tg are linear, and activation enthalpies for structural relaxation are in the range of 210–350 kJ/mol. For polymeric solutes, both the activation enthalpies for structural relaxation and the heat capacity change accompanying the glass transition increase with increasing molecular weight of the solute. Molecular weight dependence of the observed midpoint of the glass transition agrees with the Fox–Flory relationship. Results are compared and contrasted with glass transitions in solid polymers and with the glass transition of hyperquenched water. Practical implications for characterization of formulations intended for freeze-drying are discussed. 相似文献
7.
E. L’Her 《Réanimation》2014,23(1):93-98
Sedation contributes to patient’s comfort and plays an essential role in the intensive care unit (ICU). Several clinical studies have reported the occasional use of volatile halogenated agents in the ICU; however, long-term use is possible in routine for the provision of a dedicated evaporator filter (AnaConDa? [ACD]). Because of their low cost and pharmacological characteristics with a rapid therapeutic effect, a high therapeutic index, a possible use regardless of age and underlying medical conditions, and a good knowledge of their adverse effects, halogenated agents could be considered like possible ideal anesthetic agents in the ICU. The objective of this technical note is to clarify the potential indications of ACD device and describe its operative principles and potential drawbacks. 相似文献
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Recent changes in plasma transfusion practices for severe hemorrhage are largely related to the recognition of an early endogenous coagulopathy associated with traumatic injury. Observational and mostly retrospective data suggest improved survival rates with high-dose plasma therapy, up to a 1:1 ratio of fresh frozen plasma to packed red blood cells, but the quality of evidence is limited. Putting it into practice raises many issues (early identification of patients at risk of massive bleeding, extrapolation to non-trauma settings, alternative or adjunctive treatments, among others) that are discussed in this brief review. 相似文献
10.
目的通过免疫组织化学方法检测Gab1与SOD在胆管癌组织、癌旁组织和正常胆管组织中的表达,探讨它们对胆管癌发生、发展的影响,揭示胆管癌的发病机制。方法收集中国医科大学附属盛京医院2006年1月~2010年5月胆管癌标本70例,30例癌旁胆管组织,30例正常组织。用免疫组织化学方法检测Gab1与SOD的表达情况,对三组切片染色进行光密度分析。应用SPSS 13.0统计软件进行分析。对两项指标的检测数据分别进行t检验及Spearman等级相关检验。结果胆管癌组Gab1平均光密度为(0.1689±0.0268);癌旁组为(0.1471±0.0185);正常组为(0.1023±0.0119)。胆管癌组的SOD的平均光密度为(0.2205±0.0245);癌旁组为(0.1971±0.039);正常组为(0.1749±0.0151)。Gab1与SOD蛋白在胆管癌组、癌旁组、正常组表达均呈递减趋势,具有显著性差异(P<0.05)。胆管癌组织中Gab1与SOD表达呈正相关。r=0.247,P<0.05。结论 Gab1与SOD蛋白与胆管癌的发生、发展有关。Gab1的含量与SOD的含量呈正相关。 相似文献