RESUMO
Superoxide radical ( O·-2 ) , is one of reactive oxygen species ( ROS ) produced in TiO2 photocatalytic reactions, and plays an important role in the photodegradation of pollutants. In this work, we constructed two different procedures to study the generation of total O·-2 and surface-adsorbed O·-2 during TiO2 photocatalytic reaction using nitroblue tetrazolium ( NBT) as capture probe. Furthermore, three different TiO2 ( anatase, rutile and P25 ) were selected as model, and O·-2 generation and its existence form were all studied. The results showed that the generation of total O·-2 was followed by the order P25> anatase> rutile, but the surface-adsorbed O·-2 was nearly the same. The study of surface-adsorbed ROS is very important due to their probably persistence for the pollutants photodegradation or antibacterial activity.
RESUMO
Objective To investigate the metastasis mechanism by observing morphological distributions of lymphic vessels in peripheral areas of the different development of uterine cervix cancer. Methods Cancer tissues from the center, peripheral and normal areas of uterine cervix cancer respectively were collected. The paraffin sections and semithin sections which were stained with HE were applied to those tissues for exploring the configurations and distributions of lymphic vessels of the cancer under a microscope. And the ultrathin sections were applied to those tissues for exploring under a electronic microscope. Results Under the microscope, the basement membrane had been destroyed by cancer cell, which continued to infiltrate interstitial tissue. Lymphic vessels were increased and dilated in peripheral areas of uterine cervix cancer than those in normal areas. Moreover, the walls of lymphic vessels were hazy and broken. Conclusion The increase and morphologic changes of lymphic vessels in peripheral areas of uterine cervix cancer will play an important role in lymphatic metastasis.