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Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator. 相似文献
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Various 2-(4-biphenoxymethyl)-5-arylamino-1,3,4-oxadiazoles were synthesized by cyclization of the corresponding 1-(4-biphenoxyacetyl)-4-substituted thiosemicarbazides. These compounds were characterized by their elemental analyses and infrared, mass, and nuclear magnetic resonance spectral data. All substituted thiosemicarbazides (100 mg/kg, ip) and cyclized substituted oxadiazoles (100 mg/kg, ip) possessed anti-inflammatory activity, as reflected by their ability to provide protection against carrageenin-induced edema in the rat paw which ranged from 28 to 68% and 36 to 76%, respectively. Cyclization of the substituted thiosemicarbazides, in general, resulted in an increase in the anti-inflammatory activity of their corresponding substituted oxadiazoles, with the exception of those containing 2,4-dimethyl and 3,4-dimethyl substituents in their molecular structure. Hydrocortisone (10 mg/kg, ip) and oxyphenbutazone (40 mg/kg, ip) were used as the standard reference drugs and these provided 45 and 53% protection, respectively. All compounds (1 mM) possessed antiproteolytic activity and the in vitro inhibition of trypsin-induced hydrolysis of bovine serum albumin ranged from 13 to 75% for substituted thiosemicarbazides and 39 to 70% for substituted oxadiazoles. There was no relationship between the anti-inflammatory activity of substituted thiosemicarbazides and substituted oxadiazoles and their antiproteolytic effectiveness. The low toxicity of these compounds was reflected by their high approximate LD50 values, ranging from 500 to 1000 mg/kg. 相似文献
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Morning glory syndrome, an unusual developmental anomaly of the optic nerve head, presenting with funnelled enlargement of the disc with a white dot in the centre and a peripheral vascular pattern along the disc margin, with features of typical entry and exit of retinal vessels on the optic nerve head and exceptionally good vision in the involved eye with old traumatic retinal detachment in the other, in a young Indian girl is described here for its rarity and indifferent clinical presentation. Various factors in its pathogenesis are postulated. 相似文献
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7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成 总被引:1,自引:0,他引:1
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。 相似文献