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101.
柯雪红 《中国药师》2006,9(8):774-775
目的:测定舒金克喘胶囊中盐酸麻黄碱的含量。方法:用HPLC法测定,色谱条件:Hypersil ODS2 C18分析柱(150 mm×4.6 mm,5μm);流动相:1 000 ml水中加入磷酸二氢钾1.36 g、三乙胺3 ml,甲醇110 ml,加磷酸调pH 3-3.5,检测波长218 nm,流速1.0 ml·min-1,室温操作。结果:盐酸麻黄碱在0.119 6-1.196 0μg范围具良好线性:平均回收率为98.90%(RSD=1.70%,n=6)。结论:方法快速准确,样品处理简便易行。  相似文献   
102.
目的观察胆红素对离体培养的新生SD大鼠耳蜗器官的损伤效应。方法健康新生3日龄SD大鼠18只,雌雄不限,分离其双侧的内耳共得到耳蜗器官组织36个,体外培养,12h后换液。选择贴壁、存活良好的组织30个入选实验,并随机分为两组(15个/组):实验组于贴壁第二天开始进行胆红素处理,对照组加入相应体积的生理盐水。处理后24h,实验组和对照组同时终止培养,并对其进行固定、免疫组织化学染色,共聚焦显微镜观察毛细胞及螺旋神经节神经元的形态变化并计数,统计对比。结果胆红素组离体培养的耳蜗器官中螺旋神经节神经元胞体及其树突纤维与对照组相比有明显的减少,内外毛细胞形态完整,数量无明显变化。结论大鼠耳蜗器官螺旋神经节神经元对胆红素的毒性敏感,而内外毛细胞对其毒性相对不敏感。  相似文献   
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Polymorphisms in the promoter of the BRM gene, a critical subunit of the chromatin remodeling SWI/SNF complex, have previously been implicated in risk and prognosis in Caucasian‐predominant lung, head and neck, esophageal, and pancreatic cancers, and in hepatocellular cancers in Asians. We investigated the role of these polymorphisms in hepatocellular carcinoma (HCC) risk and prognosis. HCC cases were recruited in a comprehensive cancer center while the matched controls were recruited from family practice units from the same catchment area. For risk analyses, unconditional logistic regression analyses were performed in HCC patients and matched healthy controls. Overall survival analyses were performed using Cox proportional hazard models, Kaplan‐Meier curves, and log‐rank tests. In 266 HCC cases and 536 controls, no association between either BRM promoter polymorphism (BRM‐741 or BRM‐1321) and risk of HCC was identified (P > 0.10 for all comparisons). There was significant worsening of overall survival as the number of variant alleles increased: BRM‐741 per variant allele adjusted hazards ratio (aHR) 5.77, 95% confidence interval (CI) 2.89‐11.54 and BRM‐1321 per variant allele aHR 4.09, 95%CI 2.22‐7.51. The effects of these two polymorphisms were at least additive, where individuals who were double homozygotes for the variant alleles had a 45‐fold increase in risk of death when compared to those who were double wild‐type for the two polymorphisms. Two BRM promoter polymorphisms were strongly associated with HCC prognosis but were not associated with increased HCC susceptibility. The association was strongest in double homozygotes for the allele variants.  相似文献   
106.
There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndrome (PCOS). In addition to different diagnostic criteria used, the ethnic background of women with PCOS may affect the clinical, hormonal, and metabolic characteristics of this condition. We present here studies related to the clinical, hormonal, and metabolic characteristics and response to the treatment of PCOS in Asia, which may be different from those in Western countries. It is important to take into consideration the ethnic background of patients in future studies related to PCOS.  相似文献   
107.
Ectodomain shedding of epidermal growth factor receptor ligands such as transforming growth factor- alpha (TGF-alpha), heparin-binding epidermal growth factor-like growth factor (HBEGF), and amphiregulin (AREG) is considered to be important during implantation. Tumor necrosis factor-alpha converting enzyme (TACE) has been suggested as the major sheddase for these molecules. The objectives of this study are (1) to characterize the expression of TACE in the human placenta throughout gestation; (2) to determine the association between the expression of TACE with TGF-alpha, HBEGF, and AREG; (3) to ascertain whether TACE mediates TGF-alpha, HBEGF, and AREG shedding; and (4) to examine the effect of hypoxia on the expression of TACE. By analyzing a total of 55 villous samples representing different gestational ages, the authors found that TACE was continuously expressed in the placentas throughout gestation and that the levels of TACE were positively correlated with the levels of TGF-alpha, HBEGF, and AREG. Preadministration of a TACE inhibitor in villous explant cultures or transfection of cytotrophoblastic cells with TACE-specific small interference RNA decreased the shedding of HBEGF and AREG. Moreover, hypoxia (2% O(2)) caused an increase in the levels of TACE mRNA and protein in villous explants and primary cytotrophoblastic cells in vitro. These results indicate that oxygen regulates the expression of TACE and that TACE may be important for placental development during human pregnancy.  相似文献   
108.
Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active.  相似文献   
109.
Baicalin is a flavonoid present in many traditional Chinese medicines. A number of studies show that baicalin has anti-inflammatory actions and protects against a variety of tissue and organ injuries. The effect of baicalin in lipopolysaccharide (LPS)-induced acute lung injury is not well studied. In this study, typically acute lung injury was induced in rat by intratracheal injection of LPS, which increased lactate dehydrogenase activity and protein content in bronchoalveolar lavage fluid, wet/dry lung weight ratio, Evan's blue dye leakage, and neutrophil infiltration. Baicalin (20 mg/kg) was administrated 1 hour before or 30 min after LPS injection. Both pre and post-treatment with baicalin attenuated the increase of these parameters and improved histological finding. Our results suggest that baicalin has a therapeutic effect on LPS-induced acute lung injury.  相似文献   
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