在正常条件下,泪液的产量大约为每分钟1μl。由于眨眼,泪液引流到鼻侧的两个泪点。泪液不断从眼表面流过,冲洗掉微生物等物质。当眼表面受到刺激时,便引起反射性流泪。超量的泪液进一步稀释和冲洗掉微生物等物质。pH为中性的泪膜对中和进入眼附属器表面的毒性化学物质起着重要的作用。泪液包含许多在外眼防御中起重要作用的物质。例如,乳铁蛋自在正常泪液中含量丰富,平 Under normal conditions, tear production is about 1 μl per minute. Due to the blink of an eye, tears flow to the nasal side of the two punctate. Tears continue to flow from the eye surface, rinse out microbes and other substances. When the eye surface is stimulated, it causes reflex tears. Excess tears further dilute and wash away microorganisms and other substances. A pH-neutral tear film plays an important role in neutralizing toxic chemicals that enter the surface of the eye attachment. Tears contain many substances that play an important role in the defense of the outer eye. For example, lactoferrin in normal tear content, flat