sentinels

n.a person employed to watch for something to happen

同义词：lookoutlookout mansentrywatchspotterscoutpicket

Lakes and streams as sentinels of environmental change in terrestrial atmospheric processes
Skin immune sentinels in health and disease
HMGB proteins function as universal sentinels for nucleic-acid-mediated innate immune responses.
Lakes as sentinels of climate change
Mast cells as sentinels of innate immunity.
Selfish sentinels in cooperative mammals.
Epithelial Cells in the Female Reproductive Tract: a Central Role as Sentinels of Immune Protection
Transmission of Toxoplasma: clues from the study of sea otters as sentinels of Toxoplasma gondii flow into the marine environment
Bcl-2 family proteins: The sentinels of the mitochondrial apoptosis pathway
Lakes and reservoirs as sentinels, integrators, ...