Conceptual illustration of pediatric meningitis diagnosis. A child's brain, side view, shows characteristic surface inflammation. The silhouette provides a background for bacteria floating below. A lumbar cerebrospinal fluid (CSF) tap shows a needle inserted into the spinal canal. Arrows indicate fluid withdrawal used for diagnostic testing.

Close-up of a generic cochlear implant electrode inserted into the coils of the cochlea, sectioned to show the electrode and the cochlear nerve distribution. Also shown are the eardrum, malleus, incus, and stapes, which conduct sound across the middle ear (lower left). The bony labyrinth cavity structures of the inner ear are represented as solid.

Illustration of deep vein thrombosis (DVT): a posterior knee joint with the popliteal vein shown open to reveal a large venous thrombus (blood clot). DVT occurs commonly in the lower leg. When the vein becomes clogged with a thrombus, the veins feeding into it become distended and tortuous.

Conceptual illustration of chest trauma: a normal heart is shown with a swirling effect on the margins of the heart.

Conceptual illustration of bacterial and viral respiratory infections and antibiotic resistance. Bronchial airways are shown intermingled with various bacteria and virions that cause lung infections.

Conceptual illustration of chest trauma: a sectioned heart with normal atrial and ventricular anatomy is shown with a swirling effect.

Illustration of common sites for venous foot ulcers.

Chronic obstructive pulmonary disease (COPD) anatomy and pathology: a dilated terminal bronchiole (foreground); the sectioned surface of the left lung with characteristic pitting (center); and a sectioned bronchial tube with characteristic pathology (background). COPD, which includes emphysema and chronic bronchitis, is often linked to smoking.

Normal eye, parasagittal section, showing the anterior chamber, including the cornea, iris, pupil, lens, and ciliary body. The anatomy shown relates to cataracts and glaucoma.

Illustration of a normal brain, sagittal section.

Illustration of a healthy heart.

Illustration of a female "Venus" torso showing the normal female reproductive system with a diagram of the menstrual cycle in the background.

Illustration of the male torso showing the normal male urogenital system with a diagram in the background of a midsagittal section through the bladder and prostate gland.

Profile of a head showing the brain and top of spinal column.

Clear male figure with the heart visible.

Clear male figure with the heart and other organs visible.

Clear male figure from a 3/4 rear view showing the spine.

Medical illustration of the heart, shown with a cutaway section to view the interior of the chambers.

Medical illustration of the heart, shown with a cutaway section to view the interior of the chambers.

Medical illustration of fertilization, implantation of the embryo in the uterine wall, the development of the supplying blood vasculature to the embryo, and further fetal development.