HOW DO pH INDICATORS WORK? pH indicators detect the presence of H+ and OH-. They do this by reacting with H+ and OH-: they are themselves. weak acids and bases. If an indicator is a weak acid and is coloured and its conjugate base has a different. colour, deprotonation causes a colour change.
Have varicose veins, which are a common cause of superficial thrombophlebitis. Have a pacemaker or have a thin, flexible tube (catheter) in a central vein, for treatment of a medical condition, which may irritate the blood vessel wall and decrease blood flow. Are pregnant or have just given birth.
The clinical expression of cerebral venous thrombosis is variable, with headache as the most frequent presenting symptom. Cerebral venous thrombosis, which includes dural sinus thrombosis and the more unusual isolated cortical venous thrombosis (CVT), is an established cause of parenchymal hemorrhage (1 â 3).Subarachnoid hemorrhage (SAH) is a rare presentation of cerebral venous thrombosis (4).he most commonly described symptoms are headache, seizures, mental obtundation, and focal motor or sensory deficits (9). The clinical manifestations of isolated cortical vein thrombosis are less well known, but review of the literature suggests that there is similarity with dural sinus thrombosis (6, 8).