Just as economies differ in size, the two authors show, they also vary in complexity.

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Depending on its origin, a graft can differ in size, thickness and how fast it generates tissue.

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Because individual hospitals differ in size, they are compared by a standard measure of the number of cases per 1, 000 bed days.

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And unlike LDL lowering, where there is a general consensus in the field that lower is better, and it doesn't matter how you lower it, there are different HDL particles that differ in composition and size.

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The products differ in other ways besides the size of their studies.

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Because components differ a great deal in terms of size, raw material bases and manufacturing methods, it's hard to see them as one monolithic industry.

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