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1.
Vertical interpositional augmentation genioplasty with porous polyethylene   总被引:2,自引:0,他引:2  
Recent advances in the field of biomatrix porous implant technology has stirred the interest of the oral and maxillofacial surgical community. One such material (Medpor), is a biocompatible, large-pore, high-density polyethylene implant which has proven both experimentally and clinically to fulfil the criterion for maxillofacial reconstructive and aesthetic surgical grafting.  相似文献   
2.
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant.  相似文献   
3.
采用正交试验优选出最佳条件为:当乙酰乙酸乙酯为0.2moL时,硫酸铁铵0.7g,环乙烷10mL。乙酰乙酸乙酯和惭二醇摩尔比为1:1.5,反应时间为5h。所得产率为59.2%。  相似文献   
4.
讨论了一系列N-酰化壳聚糖膜的抗张强度、透水性、VB_(12)的透过性、透氧性以及血液相容性。N-已酰化壳聚糖膜具有良好的血液相容性。在制膜过程中,加入分子量为1500的聚乙二醇为致孔剂,则可使N-己酰化壳聚糖膜的渗透性有较大提高。同时保持较好的血液相容性和强度。  相似文献   
5.
Dystonia is a common movement disorder which is thought to represent a disease of the basal ganglia. However, the pathogenesis of the idiopathic dystonias, i.e. the neuroanatomic and neurochemical basis, is still a mystery. Research in dystonia is complicated by the existence of various phenotypic and genotypic subtypes of idiopathic dystonia, probably related to heterogeneous dysfunctions.In neurological diseases in which no obvious neuronal degeneration can be found, such as in idiopathic dystonia, the identification of a primary defect is difficult, because of the large number of chemically distinct, but functionally interrelated, neurotransmitter systems in the brain.The variable response to pharmacological agents in patients with idiopathic dystonia supports the notion that the underlying biochemical dysfunctions vary in the subtypes of idiopathic dystonia. Hence, in basic research it is important to clearly define the involved type of dystonia.Animal models of dystonias were described as limited. However, over the last years, there has been considerable progress in the evaluation of animal models for different types of dystonia.Apart from animal models of symptomatic dystonia, genetic animal models with inherited dystonia which occurs in the absence of pathomorphological alterations in brain and spinal cord are described.This review will focus mainly on genetic animal models of different idiopathic dystonias and pathophysiological findings. In particular, in the case of the mutant dystonic (dt) rat, a model of generalized dystonia, and in the case of the genetically dystonic hamster (dtsz), a model of paroxysmal dystonic choreoathetosis has been used, as these show great promise in contributing to the identification of underlying mechanisms in idiopathic dystonias, although even a proper animal model will probably never be equivalent to a human disease.Several pathophysiological findings from animal models are in line with clinical observations in dystonic patients, indicating abnormalities not only in the basal ganglia and thalamic nuclei, but also in the cerebellum and brainstem. Through clinical studies and neurochemical data several similarities were found in the genetic animal models, although the current data indicates different defects in dystonic animals which is consistent with the notion that dystonia is a heterogenous disorder.Different supraspinal dysfunctions appear to lead to manifestation of dystonic movements and postures. In addition to increasing our understanding of the pathophysiology of idiopathic dystonia, animal models may help to improve therapeutic strategies for this movement disorder.  相似文献   
6.
We have examined 6 construction workers who developed chronic skin diseases on their hands over a period of 15 years (1970–1985). 4 developed a Trichophyton rubrum infection, and the other 2 an irritant contact dermatitis. All of them carried out jobs which caused traumatization of the skin, due to the presence of ethylene glycol and mineral oils during operation of pneumatic hammers in winter. They also suffered other types of skin trauma during their work. Construction workers may be at risk of developing an occupational skin disease involving fungal infection.  相似文献   
7.
单甲氧聚乙二醇化学修饰药物酶的研究进展   总被引:4,自引:0,他引:4  
用单甲氧基聚乙二醉(1)化学修饰药物酶是生化药物研究开发的重要手段之一。本文综述了1化学修饰药物酶的一般方法及修饰后酶在生物和理化性质方面的变化,同时对1研究前景进行展望,并指出了尚待解决的问题。  相似文献   
8.
用适宜浓度的PEG将囊虫病人血清浓缩,达到提高血清中特异性抗体浓度的作用,从而提高检测的敏感性。该法用于囊虫病的诊断,阳性附合率83.33%.特异性较理想。  相似文献   
9.
[目的]探讨聚乙烯颗粒对人单核细胞分泌促炎因子与抗炎因子的影响.[方法]用Ceridust 3615 颗粒(聚乙烯颗粒)(平均直径14.27,6.39,1.74,1.01,0.54和0.28 μm)分别刺激人单核细胞,颗粒体积与细胞数的比例为100:1和10:1.在颗粒刺激细胞24 h后,运用ELISA检测培养上清液中的促炎因子(白介素-1β,白介素-6和细胞坏死因子α)及抗炎因子(白介素-10)的表达.[结果]Ceridust 3615 颗粒可刺激单核细胞分泌白介素-1β(IL-1β)、白介素-6(IL-6)和细胞坏死因子α(TNFα),但未能引起白介素-10(IL-10)的表达.颗粒比例增高可促使单核细胞分泌更多的IL-6和TNFα,却减少IL-1β分泌,对IL-10的分泌则无影响.个体差异使巨噬细胞对同种颗粒的刺激产生不同的反应,其差异可达到30倍.[结论]个体差异是影响人工关节寿命的重要因素,聚乙烯颗粒可刺激单核细胞产生炎因子但对产生抗炎因子(IL-10)的作用不明显,提示促炎因子与抗炎因子的不平衡或许是人工关节松动不断进展的另一重要因素.  相似文献   
10.
The potential of binary mixtures of propylene glycol–water, ethanol–water, and polyethylene glycol 400–water to cause skeletal muscle damage (myotoxicity) following intramuscular injection was examined with an in vitro model using the isolated rat muscle. At moderate concentrations (20–40%, v/v) of the organic cosolvent, the order of myotoxicity was propylene glycol > ethanol polyethylene glycol 400. The in vitro results were then compared with in vivo toxicity in rabbits after injection of normal saline, 40% (v/v) polyethylene glycol 400, 40% (v/v) propylene glycol, indocyanine green in normal saline, and indocyanine green in 40% (v/v) propylene glycol. Employing the area under the creatine kinase activity curve from 0 to 72 hr as the index of skeletal muscle damage, an excellent in vitro–in vivo correlation was observed. The basic myotoxicity relationships obtained from the binary cosolvent systems were then used to examine the myotoxicity of ternary organic cosolvent mixtures. Several mixed solvent systems with the same theoretical molar solubilization power for a model compound, diazepam, were selected to determine (1) if myotoxicity can be reduced by changing the composition of the ternary mixtures and (2) if myotoxicity of the individual components is additive. For the solvent systems containing propylene glycol, ethanol, and water, the total myotoxicity equaled the sum of the individual myotoxicity of each component. In contrast, for the solvent systems containing polyethylene glycol 400, the total myotoxicity was only half of the sum of individual toxicities. These results suggest that polyethylene glycol 400 in mixed cosolvent systems might have a protective effect on the myotoxicity generated by intramuscular injections.  相似文献   
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