葡萄糖诱发小鼠胰岛β细胞氢离子流改变的测定

目的:实时记录C57BL/6J小鼠胰岛β细胞原位状态下的氢离子(H+)流,观察其在葡萄糖刺激下的改变,以了解其在胰岛素分泌过程中的作用。方法:取8周龄雄性C57BL/6J小鼠,急性分离胰岛,置于含10%小牛血清的RPMI1640培养基中孵育12h,应用非损伤微测技术检测20mmol/L葡萄糖对胰岛β细胞H+流的影响。结果:胰岛原位β细胞有基础性H+外流存在,检测48个胰岛的β细胞H+流,测得基础流速为(0.0205±0.0019)pmol/(cm2·s),葡萄糖刺激后的流速增加为(0.0519±0.0063)pmol/(cm2·s),差异显著(t=33.128,P<0.05)。结论:通过非损伤微测技术,首次实时记录到胰岛β细胞原位状态下的H+外流,并发现其在葡萄糖刺激下的流速增加,为进一步研究胰岛β细胞H+流在胰岛素分泌过程中的作用提供了实验基础,对于深入探讨糖尿病的发生机制具有重要作用。

紫薇抗寒性鉴定方法比较研究

为探讨紫薇抗寒性能力之间的差异,以7个紫薇品种为试验材料,采用电导法、叶绿素荧光法和非损伤微测计数法对紫薇进行抗寒性鉴定,并与田间观察试验对比,研究了低温对紫薇抗寒性指标的影响及不同鉴定方法与抗寒性之间的关系。结果表明:不同测定方法得到的抗寒性结果略有不同,与大田观测结果相似,7个紫薇品种中以2号紫薇品种抗旱性最强,1号、5号和6号抗寒性较弱。植物抗寒性鉴定需要多种测定的综合评价。

Photocatalytic hydrogen evolution activity over MoS_2/ZnIn_2S_4 microspheres

MoS2/ZnIn2S4composites with MoS2anchored on the surface of ZnIn2S4microspheres were synthesized by a two‐step hydrothermal process.The obtained samples were characterized by X‐ray diffraction,field emission scanning electron microscopy,energy dispersive X‐ray spectroscopy,high‐resolution transmission electron microscopy,X‐ray photoelectron spectroscopy,Raman spectroscopy,ultraviolet–visible diffuse reflectance absorption spectroscopy,nitrogen adsorption–desorption measurements,photoluminescence spectroscopy,and photoelectrochemical tests.The influence of the loading of MoS2on the photocatalytic H2evolution activity was investigated using lactic acid as a sacrificial reagent.A H2evolution rate of343μmol/h was achieved under visible light irradiation over the1wt%MoS2/ZnIn2S4composite,corresponding to an apparent quantum efficiency of about3.85%at420nm monochromatic light.The marked improvement of the photocatalytic H2evolution activity compared with ZnIn2S4can be ascribed to efficient transfer and separation of photogenerated charge carriers and facilitation of the photocatalytic H2evolution reaction at the MoS2active sites.

Study of influence of hiatus hernia on gastroesophageal reflux

AIM To explore whether the presence of a sliding hiatus hernia influences gastroesophageal reflux.