The halogens all form binary compounds with hydrogen, and these compounds are known as the hydrogen halides: hydrogen fluoride (HF), hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen iodide (HI), and hydrogen astatide (HAt).
finger stick. 1  the act of puncturing the tip of the finger to obtain a small sample of capillary blood. In some procedures the hand may be first immersed in warm water for 10 minutes to arterialize the capillary blood or give it characteristics similar to those of arterial blood.
Digital clubbing is an ancient and important clinical signs in medicine. Although clubbed fingers are mostly asymptomatic, it often predicts the presence of some dreaded underlying diseases. Its exact pathogenesis is not known, but platelet-derived growth factor and vascular endothelial growth factor are recently incriminated in its causation.