Vein limbs. The Thebesian veins within the myocardium of the heart are valveless veins that drain directly into the chambers of the heart. The coronary veins all empty into the coronary sinus which empties into the right atrium. The dural venous sinuses within the dura mater surrounding the brain receive blood from the brain and also are a point of entry of cerebrospinal fluid from arachnoid villi absorption. Blood eventually enters the internal jugular vein. "Phlebology" is the medical specialty devoted to the diagnosis and treatment of venous disorders. A medical specialist in phlebology is termed a phlebologist. A related image
Driving in the United States the flow of oxygen in the blood to the brain and other body parts. It affects people with heart disease and the central nervous system. Sulfur oxides are the cause of acid rain that damages the nature and human health. It particularly aggravates heart and lung diseases in children and the elderly. Nitrogen oxides are the main ingredients in the formation of acid rain and ground-level ozone that contributes to the global warming. Hydrocarbons are pollutants of air toxics and hazardous to the lung and other body parts. It causes cancer and birth defects. Finally, high-lead level in the air