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This retrospective study examined whether a delay of greater than 12 hours is associated with an increased risk of perioperative complications in the operative treatment of supracondylar humerus fractures in children. Of 150 consecutive children with supracondylar fractures, 50 underwent surgery in less than 12 hours and 100 underwent surgery greater than 12 hours after injury. There was no significant difference between groups in rate of open reduction (P = 0.55), pin tract infection (P = 1.0), iatrogenic nerve injury (P = 1.0), vascular complication (P = 0.33), or compartment syndrome (P = 1.0), including when Gartland type III fractures were analyzed independently. There was no iatrogenic nerve injury, no compartment syndrome, and one pin tract infection in 150 patients. The study confirms previous retrospective studies finding no significant difference in perioperative complications or rate of open reduction in children undergoing early versus delayed surgical treatment of supracondylar humerus fractures.  相似文献   
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A sensitive, selective, precise and stability-indicating high-performance thin layer chromatography (HPTLC) method for analysis of indinavir sulphate both as a bulk drug and in formulations was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60F-254 as the stationary phase. The solvent system consisted of carbon tetrachloride/chloroform/methanol/10% v/v ammonia (4:4.5:1.5:0.05, v/v/v/v). Densitometric analysis of indinavir sulphate was carried out in the absorbance mode at 260 nm. This system was found to give compact spots for indinavir sulphate (Rf value of 0.43 +/- 0.02, for six replicates). Indinavir sulphate was subjected to acid and alkali hydrolysis, oxidation, dry and wet heat treatment, and photo degradation. The drug undergoes degradation under acidic and basic conditions, oxidation, dry and wet heat treatment, and photo degradation. Also the degraded products were well resolved from the pure drug with significantly different Rf values. The method was validated for linearity, precision, robustness, limit of detection (LOD), limit of quantitation (LOQ), specificity and accuracy. Linearity was found to be in the range of 100-6000 ng/spot with significantly high value of correlation coefficient r2 = 0.997 +/- 0.64. The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.999 +/- 0.002 in the working concentration range of 1000-6000 ng/spot. The LOD and LOQ were 40 and 120 ng/spot, respectively. Statistical analysis proves that the method is repeatable and specific for the estimation of the said drug. As the method could effectively separate the drug from its degradation products, it can be employed as a stability-indicating one. Moreover, the proposed HPTLC method was utilized to investigate the kinetics of acid degradation process. Arrhenius plot was constructed and activation energy was calculated.  相似文献   
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PURPOSE: To examine an immortalized mouse retinal cell line (661W) for markers characteristic of photoreceptor cells and validate its photoreceptor origin. METHODS: The 661W cells were cloned from retinal tumors of a transgenic mouse line that expresses the simian virus (SV) 40 T antigen under control of the human interphotoreceptor retinol-binding protein (IRBP) promoter. Morphologic, immunocytochemical, and immunoblot analyses were performed to characterize these cells. Total cellular protein was used for immunoblot analysis of various photoreceptor-specific proteins. RESULTS: 661W cells grew as a monolayer and exhibited processes characteristic of neuronal cells. Immunoblot analysis showed that 661W cells expressed SV40 T antigen, blue and green cone pigments, transducin, and cone arrestin. Immunocytochemical detection of blue and green opsins showed distribution throughout the cell, the nucleus included. However, these cells did not express rod-specific antigens, such as opsin and arrestin or rod- and cone-specific proteins such as phosducin, peripherin/rds, and ROM1. Furthermore, the cells did not express RPE65, a cone- and RPE-cell-specific protein. CONCLUSIONS: 661W cells demonstrate cellular and biochemical characteristics exhibited by cone photoreceptor cells. These cells also resemble neuronal cells with their spindlelike processes and should serve as a useful alternative in vitro model for the study of cone photoreceptor cell biology and associated diseases.  相似文献   
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