Cooking at a constant oven temperature of 300Â°F (160Â°C), a 5- to 8-lb standing rib roast will take 17-19 minutes per pound for rare, 20-22 for medium rare, 23-25 minutes for medium, and 27-30 minutes for well done.f you roast at 325Â°F (160Â°C), subtract 2 minutes or so per pound. If the roast is refrigerated just before going into the oven, add 2 or 3 minutes per pound. More: Set the roast out an hour or so before putting it in the oven.
Research suggests schizophrenia may be caused by a change in the level of two neurotransmitters: dopamine and serotonin. Some studies indicate an imbalance between the two may be the basis of the problem. Others have found a change in the body's sensitivity to the neurotransmitters is part of the cause of schizophrenia.
Similar phenomena have been found in both early-onset groups, 4 suggesting that age of onset causes the differences in clinical presentation. Risk factors. As with early-onset schizophrenia, family history is the most common cause of very late-onset schizophrenia.