Effect of Single-walled Carbon Nanotubes on Cellulose Phenylcarbamate Chiral Stationary Phases

Single-walled carbon nanotubes（SWNTs） have a high adsorption ability and nanoscale interactions. Cellulose trisphenylcarbamates possess high enantioseparation ability in high-performance liquid chromatography（HPLC）. Single-walled carbon nanotubes mixed with cellulose trisphenylcarbamate are coated on the silica gel as chiral stationary phases and higher enantioseparation factors are obtained. After a single-walled carbon nanotube is linked to the 6-pesition of cellulose 2,3-bisphenylcarbamate, its enantioseparation resolution increases compared to that of the cellulose trisphenylcarbamate. It is the first time that SWNTs have been applied to enantioseparation. The results indicate that the single-walled carbon nanotubes are good promoters of chiral recognition. This method can be used to improve the enantioseparation efficiency of the polysaccharide chiral stationary phases.

虫草素对Ⅱ型糖尿病勃起功能障碍大鼠阴茎海绵体组织中CX43表达的影响

目的:研究虫草素对Ⅱ型糖尿病勃起功能障碍大鼠阴茎海绵体组织中缝隙连接蛋白43 (CX43)表达的影响。方法:50只雄性SD大鼠,随机选取10只作为空白对照组喂饲普通饲料,其余大鼠喂饲高脂饲料并单次腹腔注射STZ溶液诱发Ⅱ型糖尿病模型。将Ⅱ型糖尿病造模成功的大鼠随机分为4组:糖尿病模型组、虫草素低剂量组(10.0 mg/kg)、虫草素高剂量组(30.0 mg/kg)以及阳性药对照组(西地那非5.0 mg/kg)。连续给药6周后观测大鼠的性行为、海绵体内压、阴茎海绵体组织形态并采用免疫组化检测海绵体组织中CX43表达。结果:与糖尿病模型组相比,虫草素高剂量组扑捉潜伏期及扑捉次数极显著改善(P<0.01)、海绵体内压与平均动脉压的比值显著提高(P<0.05);虫草素高剂量组的阴茎海绵体组织结构形态明显改善;免疫组化结果显示:CX43主要表达于阴茎海绵体平滑肌细胞,与模型组相比,虫草素高剂量组阴茎海绵体组织CX43表达极显著升高(P<0.01)。结论:虫草素能有效改善Ⅱ型糖尿病大鼠的勃起功能,上调阴茎海绵体组织中缝隙连接蛋白CX43表达。

海水中硫化物的气相分子吸收光谱测定法

目的建立海水中硫化物的气相分子吸收光谱测定法。方法水样加入固定剂后,采用均质吹扫方式进样,在吸收波长200 nm处测定其对特征光谱吸收信号,外标法定量。结果在0.25~5.00 mg/L的范围内,所得硫化物的回归方程为y=0.0856x+0.0006,r=1.000。该方法的检出限为0.005 mg/L,回收率在97.6%~100%之间,RSD为1.1%。结论该方法具有操作简便、药品用量少、检出限低、精密度和准确度高等优点,可以满足批量海水中硫化物的测定。