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91.
An efficient method for the quantitative determination of acetaminophen (AAP) and diclofenac sodium (DS) in commercial suppositories based on partial least squares (PLS) treatment of FT‐Raman spectra is described. The relative standard errors of prediction (RSEP) were calculated for calibration and validation data sets to evaluate the quality of the constructed models. In the case of DS determination, RSEP error values of 1.9 % and 2.3 % for the calibration and validation data sets, respectively, were found. For AAP these errors amounted to 1.6–2.3 % and 1.8–2.8 %, respectively, for the different calibration models. Four commercial preparations containing 5, 12.5, 16.7 and 33.3 % (w/w) AAP and one containing 5 % (w/w) DS were successfully quantified using the developed models. Concentrations derived from the developed models correlated strongly with the declared values and yielded recoveries of 99.4–100.2 % and 99.6 % for AAP and DS, respectively. The proposed procedure can be used as a fast, economic and reliable method for quantification of the active pharmaceutical ingredients in suppositories. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
92.
The aim of this ex vivo study was to evaluate the infiltration capability and rate of microleakage of a low-viscous resin infiltrant combined with a flowable composite resin (RI/CR) when used with deproteinised and etched occlusal subsurface lesions (International Caries Detection and Assessment System code 2). This combined treatment procedure was compared with the exclusive use of flowable composite resin (CR) for fissure sealing. Twenty premolars and 20 molars revealing non-cavitated occlusal carious lesions were randomly divided into two groups and were meticulously cleaned and deproteinised using NaOCl (2%). After etching with HCl (15%), 10 premolar and 10 molar lesions were infiltrated (Icon/DMG; rhodamine B isothiocyanate (RITC)-labelled) followed by fissure sealing (G-?nial Flo/GC; experimental group, RI/CR). In the control group (CR), the carious fissures were only sealed. Specimens were cut perpendicular to the occlusal surface and through the area of the highest demineralisation (DIAGNOdent pen, KaVo). Using confocal laser-scanning microscopy, the specimens were assessed with regard to the percentage of caries infiltration, marginal adaption and internal integrity. Within the CR group, the carious lesions were not infiltrated. Both premolar (57.9%± 23.1%) and molar lesions (35.3%± 22.1%) of the RI/CR group were uniformly infiltrated to a substantial extent, albeit with significant differences (P=0.034). Moreover, microleakage (n=1) and the occurrence of voids (n=2) were reduced in the RI/CR group compared with the CR group (5 and 17 specimens, respectively). The RI/CR approach increases the initial quality of fissure sealing and is recommended for the clinical control of occlusal caries.  相似文献   
93.
目的 探讨高氧对新生大鼠肺泡Ⅱ型上皮(alveolar epithelial typeⅡ,ATⅡ)细胞钠转运功能的影响.方法 分离提取新生大鼠ATⅡ细胞,随机分成高氧组和对照组,分别在氧浓度为85%和21%的细胞培养箱中原代培养.应用Western blot方法和全细胞膜片钳技术检测高氧暴露后上皮钠通道(epithelial sodium channel,ENaC)蛋白表达变化及高氧对阿米洛利敏感性钠电流的影响.结果 高氧使新生大鼠ATⅡ细胞中β-ENaC和γ-ENaC表达增加[β-ENaC:(1 d:0.43±0.06 vs0.32 ±0.04,P=0.047;2 d:0.73 ±0.06 vs 0.50±0.08,P=0.019;3 d:0.72±0.08 vs 0.52±0.06,P=0.027);γ-ENaC:(1 d:0.64 ±0.05 vs 0.53 ±0.05,P =0.044;2 d:0.76 ±0.03 vs 0.52 ±0.04,P =0.001;3 d:0.77±0.06 vs 0.61 ±0.05,P=0.025)],同时使阿米洛利敏感性钠电流增强(1 d:13.71±2.77 vs 8.92±1.38,P<0.001;2 d:29.12±11.03 vs 10.41±1.80,P<0.001),面对α-ENaC表达表现出一定的抑制作用(1 d:0.31 ±0.05 vs 0.46 ±0.05,P =0.025;2 d:0.30 ±0.01 vs 0.38 ±0.02,P =0.002;3 d:0.37 ±0.06vs 0.37 ±0.08,P=0.983).结论 高氧促进了 ATⅡ细胞ENaC钠转运功能,ENaC功能障碍并非高氧暴露后肺水肿发生的主要原因.  相似文献   
94.
95.
鱼腥草抗炎药理作用机制的研究进展   总被引:1,自引:0,他引:1  
鱼腥草为传统的清热解毒中药,临床应用多年,被卫生部列为药食两用、极具开发潜力的资源。药理研究表明,鱼腥草在炎症性疾病方面表现出较好的疗效。综述国内外关于鱼腥草抗炎的药理作用机制的研究进展,并分析了今后研究的方向和思路,为研究与开发以鱼腥草为原料的抗炎新药提供参考。  相似文献   
96.
Terminalia arjuna has been marked as a potential cardioprotective agent since vedic period. The present study was aimed to investigate the effects of butanolic fraction of Terminalia arjuna bark (TA-05) on Doxorubicin (Dox)-induced cardiotoxicity. Male wistar rats were used as in vivo model for the study. TA-05 was administered orally to Wistar rats at different doses (0.42 mg/kg, 0.85 mg/kg, 1.7 mg/kg, 3.4 mg/kg and 6.8 mg/kg) for 6 days/week for 4 weeks. Thereafter, all the animals except saline and TA-05-treated controls were administered 20 mg/kg Dox intraperitonially. There was a significant decrease in myocardial superoxide dismutase (38.94%) and reduced glutathione (23.84%) in animals treated with Dox. Concurrently marked increase in serum creatine kinase-MB (CKMB) activity (48.11%) as well as increase in extent of lipid peroxidation (2.55-fold) was reported. Co-treatment of TA-05 and Dox resulted in an increase in the cardiac antioxidant enzymes, decrease in serum CKMB levels and reduction in lipid peroxidation as compared to Dox-treated animals. Electron microscopic studies in Dox-treated animals revealed mitochondrial swelling, Z-band disarray, focal dilatation of smooth endoplasmic reticulum (SER) and lipid inclusions, whereas the concurrent administration of TA-05 led to a lesser degree of Dox-induced histological alterations. These findings suggest that butanolic fraction of Terminalia arjuna bark has protective effects against Dox-induced cardiotoxicity and may have potential as a cardioprotective agent.  相似文献   
97.
AIM: Hyaluronate plays an important role in the regulation of cervical function during parturition. In our previous study we showed that 4-methylumbelliferone (MU) suppresses hyaluronate synthesis by cultured human skin fibroblasts. The present study investigated the effects of MU on fibroblasts obtained from the human uterine cervix and assessed the possibility of controlling cervical ripening with MU. METHODS: Human uterine cervical fibroblasts were collected from uterine cervices obtained from the uteri of three patients who had a total hysterectomy for uterine myoma at Hirosaki University Hospital. The fibroblasts were cultured in Dulbecco's modified Eagle's medium until confluence. They were then cultured in medium containing [3H]glucosamine (0.074 MBq/mL) with various MU doses. Hyaluronate synthesis was evaluated by assessing the incorporation of [3H]glucosamine into the soluble fraction of hyaluronate. Three independent studies were carried out on each specimen to clarify whether MU causes compositional changes or promotes hyaluronate degradation, whether the inhibitory effects of MU on hyaluronate synthesis are dose-dependent, and whether the effects of MU are reversible. RESULTS: MU added to the medium of the cultured cells reduced the synthesis of hyaluronate in a dose-dependent manner. After MU was removed from the medium, hyaluronate synthesis recommenced, and the amount of [3H]hyaluronate synthesized was similar to the control level. CONCLUSIONS: MU inhibits the synthesis of hyaluronate in human uterine cervical fibroblasts.  相似文献   
98.
目的:探讨帕瑞昔布钠超前镇痛对髋关节置换术后患者炎症细胞因子的影响,并进一步观察术后镇痛效果。方法本组患者60例,年龄40~65岁,ASAⅠ-Ⅱ级,择期在全麻下行髋关节置换术。随机分成观察组和对照组,每组30例。麻醉前20 min观察组静脉注射帕瑞昔布钠40 mg(用生理盐水稀释成4 mL),对照组静脉注射生理盐水4 mL。分别于静推帕瑞昔布钠或生理盐水前10 min(T1)、术毕(T2)、术后6 h(T3)、术后12 h(T4)、术后24 h(T5)采上肢静脉血样,测定IL-6、TNF-α的血浆浓度。采用视觉模拟评分法(VAS)评价术毕即刻、术后2 h、6 h、12 h、24 h镇痛效果。结果患者血浆IL-6浓度于T3、T4、T5时点较术前显著升高,差异有统计学意义(P〈0.05);观察组血浆IL-6浓度于T3、T4、T5时点比对照组显著降低,差异有统计学意义(P〈0.05)。患者血浆TNF-α浓度于T4、T5时点较术前显著升高,差异有统计学意义(P〈0.05);观察组血浆TNF-α浓度在T4、T5时间点比对照组显著降低,差异有统计学意义(P〈0.05)。观察组患者在术毕即刻、术后2 h、6 h、12 h VAS评分均显著低于对照组,差异有统计学意义(P〈0.05)。结论帕瑞昔布钠超前镇痛可有效缓解全髋关节置换术患者术后疼痛,抑制炎性介质释放,降低神经系统敏感性,利于患者术后康复。  相似文献   
99.
BERH-2肝癌大鼠红细胞膜K~+依赖性磷酸酶活性与正常大鼠无显著差异。但是,K~+对酶的变构激活及F~-对酶的变构抑制却差别显著,其Hill系数不同于正常大鼠。此差别在0.10mg/ml Triton X-100存在时消失,因此,Hill系数的差异可能由于BERH-2肝癌大鼠红细胞膜中脂质成分与正常的不同所致。  相似文献   
100.
目的研究超量焦亚硫酸钠摄入对小鼠肾显微结构的影响,探讨焦亚硫酸钠对小鼠的毒性作用。方法健康雄性昆明属小鼠,随机分对照组和实验组,对照组小鼠喂食自来水,实验组小鼠代以1%焦亚硫酸钠溶液喂食。10 d后,处死小鼠,取出肾,常规石蜡制片染色,光镜观察。结果实验组小鼠肾组织中,近曲小管细胞的胞质呈水样变性。结论1%焦亚硫酸钠对小鼠肾脏有毒性作用。  相似文献   
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