By 1903, researchers had determined that sleeping sickness was caused by a trypanosome, a parasite that lived and multiplied extracellularly in the blood and tissue fluids of its human hosts.
Some of the exuded tissue fluid is also funnelled by lymphatics to the regional lymph nodes, flushing bacteria along to start the recognition and attack phase of the adaptive immune system.
24.
When an antigen enters the blood or tissue fluids it is assumed that it will attach to the surface of any lymphocyte carrying reactive sites which correspond to one of its antigenic determinants.
25.
The probe is continuously perfused with an aqueous solution ( perfusate ) that closely resembles the ( ionic ) composition of the surrounding tissue fluid at a low flow rate of approximately 0.1-5?L / min.
26.
At the arterial end of a vessel, the hydrostatic pressure is greater than the osmotic pressure, so the net movement ( see net flux ) favors water and other solutes being passed into the tissue fluid.
27.
This requires healthy blood flow, but since it has been suggested that " when ice is applied to a body part for a prolonged period, nearby lymphatic vessels begin to dramatically increase their permeability ( lymphatic vessels are dead-end tubes which ordinarily help carry excess tissue fluids back into the cardiovascular system ).
28.
Eventually in the systemic capillaries exchange with the tissue fluid and cells of the body occurs; oxygen and nutrients are supplied to the cells for their metabolism and exchanged for carbon dioxide and waste products In this case, oxygen and nutrients exit the systemic capillaries to be used by the cells in their metabolic processes, and carbon dioxide and waste products will enter the blood.
