Authorization of COVID-19 clinical trials: lessons from 2 years of experience of a national competent authority.

The COVID-19 pandemic was immediately marked by strong clinical research activity. The French national competent authority presents the data on request for authorization during the first 2 years of COVID-19 pandemic to inform discussions on future clinical research issues. Applications for authorization of interventional COVID-19 trials submitted between March 2020 and February 2022 were analysed.

[The place of natural science within the 19th-century science curriculum].

The place allotted in 19th century to natural science among the various scientific disciplines depended greatly on the level of teaching. For a long time natural science was combined with physical science on the program of the Agregation examination, occupying a modest place in secondary education, where mathematics predominated. It should be empahsized, however, that natural science represented a preferential area of investigation of early female doctoral theses.

Biology of the human myeloma cell population. II. Cytokinetic characteristics.

A kinetic study of five human myeloma cell populations before and after chemotherapy using cytochemical and autoradiographical techniques showed: 1. a large number of cells, with a DNA content intermediate between 2c and 4c, that did not incorporate thymidine ('U' cells) and were indicative of ineffective myelomapoiesis; 2. non cell cycle-specific (cyclophosphamide) followed by cell cycle-specific (vincristine) treatment led to an increase in the 3H-thymidine labelling index (LI) and activation of macromolecular synthesis (increased uridine and leucine uptake and actinomycin binding capacity) pointing to early cell recruitment.

Biology of the human myeloma cell population. I.Macromolecular characteristics.

Several human myeloma cell populations were studied using a combination of cytochemical (Unna-Pappenheim and naphthol yellow staining, Feulgen reaction) and autoradiographical (uridine, leucine, thymidine uptake and actinomycin binding) techniques. Progressive differentiation of the myeloma population was associated with: 1. a loss of proliferative activity, 2.