chemistry 189 Chemistry 171 QD Chemistry 142 human 105 Humans 99 Technology: general issues 85 Research & information: general 68 Article 59 Materials science 58 Industrial chemistry and chemical engineering 56 procedures 56 controlled study 47 Spectrum analysis, spectrochemistry, mass spectrometry 46 surface property 41 Materials Testing 34 materials testing 34 Research and information: general 32 Organic chemistry 29 Surface Properties 29 drug effect 29 in vitro study 29 metabolism 27 Analytical chemistry 26 Animals 25 animal 25 Polymer chemistry 24 male 24 scanning electron microscopy 24 In Vitro Techniques 23 Male 23