A random sample of 253 Canadian women aged 18 to 34 found a mean blood cholesterol level of 4.5 millimoles per liter (mmol/l), with a standard deviation 0.8 mmol/l. A sample of 199 Canadian young men in the same study had a mean blood cholesterol level of 4.7 mmol/l and a standard deviation of 0.9 mmol/l. Is there a significant difference between the mean blood cholesterol levels of Canadian young women and young men?