| Metrial Gland |
| Metribolone |
| Metrizamide |
| Metrizoate |
| Metronidazole |
| Metrorrhagia |
| Metyrapone |
| Mevinphos |
| Mexican Americans |
| Mexiletine |
| Mezlocillin |
| Mianserin |
| Mibefradil |
| Mice |
| Mice Minute Virus |
| Mice, Biozzi |
| Mice, Congenic |
| Mice, Inbred CFTR |
| Mice, Inbred HRS |
| Mice, Inbred mdx |
| Mice, Inbred MRL lpr |
| Mice, Inbred NOD |
| Mice, Inbred SENCAR |
| Mice, Inbred Strains |
| Mice, Jimpy |
| Mice, Knockout |
| Mice, Mutant Strains |
| Mice, Neurologic Mutants |
| Mice, Nude |
| Mice, Obese |
| Mice, Quaking |
| Mice, SCID |
| Mice, Transgenic |
| Micelles |
| Miconazole |
| Microarray Analysis |
| Microbial Collagenase |
| Microbial Sensitivity Tests |
| Microbial Viability |
| Microbiologic Phenomena |
| Microbiological Techniques |
| Microbiology |
| Microbodies |
| Microbubbles |
| Microcephaly |
| Microchemistry |
| Microchip Analytical Procedures |
| Microcirculation |
| Microclimate |
| Micrococcaceae |
| Micrococcal Nuclease |
| Micrococcus |
| Micrococcus luteus |
| Microcomputers |
| Microcystis |
| Microdialysis |
| Microdissection |
| Microelectrodes |
| Microfibrils |
| Microfilament Proteins |
| Microfilaments |
| Microfilaria |
| Microfluidic Analytical Techniques |
| Microfluidics |
| Microglia |
| Micrognathism |
| Microinjections |
| Micromanipulation |
| Micromonospora |
| Micromonosporaceae |
| Micronesia |
| Micronuclei, Chromosome-Defective |
| Micronucleus Tests |
| Micronucleus, Germline |
| Micronutrients |
| Microphthalmia-Associated Transcription Factor |
| Microphthalmos |
| Microradiography |
| MicroRNAs |
| Microsatellite Repeats |
| Microscopic Angioscopy |
| Microscopy |
| Microscopy, Acoustic |
| Microscopy, Atomic Force |
| Microscopy, Confocal |
| Microscopy, Electron |
| Microscopy, Electron, Scanning |
| Microscopy, Electron, Scanning Transmission |
| Microscopy, Electron, Transmission |
| Microscopy, Energy-Filtering Transmission Electron |