The ratio of BUN to creatinine is usually between 10:1 and 20:1. An increased ratio may be due to a condition that causes a decrease in the flow of blood to the kidneys, such as congestive heart failure or dehydration.
However, there has been research in this area. In germany, frankincense (boswellia serrata) is aparently considered a standard treatment for cancer in brain because it is one of the few substances believed to cross the BBB. Wormwood (Artemisia absinthium) is another possibility.owever, there has been research in this area. In germany, frankincense (boswellia serrata) is aparently considered a standard treatment for cancer in brain because it is one of the few substances believed to cross the BBB. Wormwood (Artemisia absinthium) is another possibility.
The H+ in the blood, however, cannot cross the blood-brain barrier, and thus cannot influence the medullary chemoreceptors. Carbon dioxide in the arterial blood can cross the blood-brain barrier and, through the formation of carbonic acid, can lower the pH of cerebrospinal fluid (fig. 16.30).n increase in blood CO2 stimulates breathing indirectly by lowering the pH of blood and cerebrospinal fluid (CSF). This figure illustrates how a rise in blood CO2 increases the H+ concentration (lowers the pH) of CSF and thereby stimulates chemoreceptor neurons in the medulla oblongata.