Primary prostatic cancer's spread to the spine.

Esophageal reflux.

Peptide chain.

Medical illustration showing blood pressure test on artery.

Detail of alveolus showing inflammatory response in severe pneumonia (mitigation of neutrophils, lymphocytes and macrophage to defeat the disease-causing agents), as well as seepage of fluid into.alveolus and surrounding tissue (pulmonary edema).

Elements of the immune system.

Schematic representation of metastasis process.

Coronary plaque.

Medical illustration of the mechanism of drug addiction.

Male figure with stylized organs (brain, lungs, liver, heart, pancreas, kidneys and bladder) connected to a computer and a digital readout.

Pencil sketch of a baby being held.

Medical illustration showing an uncircumcised penis with labels identifying the penis and scrotum.