Objective To investigate the effects of astragalus membranaceus and angelica sinensis on grafted cochlea stem cells apoptosis in hearing imparied rats.Methods The hearing impaired rats were divided into 3 groups:cochlea stem cells group(45 rats),astragalus membranaceus and angelica sinensis group(45 rats),and the control group(35 rats).Cochlea stem cells only were grafted into the first group cochlea regions,mixture of stem cells and astragalus membranaceus and angelica sinensis were grafted into that of the second group.Saline was grafted into that of control rats.Observed was apoptosis at 1 day,3 days,5 days,10 days,15 days after the transplantation by CASPASE-3 and Bcl-2 immunofluorescence.Results After transplantationn 1 day,3 days,5 days,10 days,and 15 days of five time,for the cochlea stem cell group,the rates of apoptotic cells were 27.84%,49.37%,44.78%,39.37%,and 34.82%,respectively.The rates of astragalus membranaceus and angelica sinensis group were 18.35%,26.92%,23.18%,21.38%,and 18.19%,respectively.The percent of grafted cochlea stem cells apoptosis in astragalus membranaceus and angelica sinensis group was much lower than that in cochlea stem cells group and control group.The majority of apoptotic cells occurred within three to five days after transplantation.Conclusion The majority of apoptotic cells occur within three to five days after transplantation in the hearing impaired rats.The astragalus membranaceus and angelica sinensis could reduce the apoptotic rates of transplanted stem cells.

Objective:In order to understand the current situation of air toxic substances without occupational exposure limits (OELs) in the workplace in the Germany GESTIS Substance Database, and to provide an effective reference for formulating OELs of corresponding toxic substances and improving health standards.Methods:From March 2022 to May 2023, based on the standard of GBZ 2.1-2019 Occupational Exposure Limits for Hazardous Agents in the Workplace-Part 1: Chemical Hazardous Agents, air toxic substances without OELs in the standard of GBZ/T 300.1-2017 Determination of Toxic Substances in Workplace Air-Part 1: General Principles were screened out, then corresponding OELs in other countrie/regions were queried through the Germany GESTIS Substance Database.Results:Among the 333 kinds (classes) of air toxic substances in 160 parts of GBZ/T 300.1-2017 standard, 48 kinds (classes) of air toxic substances were screened out and had not yet been formulated OELs in GBZ 2.1-2019 standard. By querying the Germany GESTIS Substance Database, it was found that among the 48 kinds (classes) of air toxic substances, 35 kinds (classes) of air toxic substances had both 8-hour occupational exposure limit and short-term occupational exposure limit, 4 kinds (classes) of air toxic substances had 8-hour occupational exposure limit but no short-term occupational exposure limit, 9 kinds (classes) of air toxic substances hadn't been retrieved any OELs. In addition, standard test methods of 7 kinds of air toxic substances hadn't been published in the present, including trimethylchlorosilane, trimethylbenzenes, cumene, chloroethane, chloropropane, dibromoethane and acetophenone.Conclusion:In the process of formulating or revising the standards of GBZ 2.1-2019 and GBZ/T 300, the latest published OELs in the Germany GESTIS Substance Database could be used as a reference basis.

Objective:In order to understand the current situation of air toxic substances without occupational exposure limits (OELs) in the workplace in the Germany GESTIS Substance Database, and to provide an effective reference for formulating OELs of corresponding toxic substances and improving health standards.Methods:From March 2022 to May 2023, based on the standard of GBZ 2.1-2019 Occupational Exposure Limits for Hazardous Agents in the Workplace-Part 1: Chemical Hazardous Agents, air toxic substances without OELs in the standard of GBZ/T 300.1-2017 Determination of Toxic Substances in Workplace Air-Part 1: General Principles were screened out, then corresponding OELs in other countrie/regions were queried through the Germany GESTIS Substance Database.Results:Among the 333 kinds (classes) of air toxic substances in 160 parts of GBZ/T 300.1-2017 standard, 48 kinds (classes) of air toxic substances were screened out and had not yet been formulated OELs in GBZ 2.1-2019 standard. By querying the Germany GESTIS Substance Database, it was found that among the 48 kinds (classes) of air toxic substances, 35 kinds (classes) of air toxic substances had both 8-hour occupational exposure limit and short-term occupational exposure limit, 4 kinds (classes) of air toxic substances had 8-hour occupational exposure limit but no short-term occupational exposure limit, 9 kinds (classes) of air toxic substances hadn't been retrieved any OELs. In addition, standard test methods of 7 kinds of air toxic substances hadn't been published in the present, including trimethylchlorosilane, trimethylbenzenes, cumene, chloroethane, chloropropane, dibromoethane and acetophenone.Conclusion:In the process of formulating or revising the standards of GBZ 2.1-2019 and GBZ/T 300, the latest published OELs in the Germany GESTIS Substance Database could be used as a reference basis.