[单选题] 全身化脓性感染作血细菌培养,其最佳采血时间是
A.寒战、高热时
B.高热间歇时
C.空腹时
D.输入抗菌药物时
E.输入抗生素后

We can begin our discussion of "population as global issue" with what most persons mean when they discuss "the population problem": too many people on earth and a too rapid increase in the number added each year. The facts are not in dispute; it was quite right to employ the analogy that likened demographic growth to "a long, thin powder fuse that burns steadily and haltingly until it finally reaches the charge and explodes".
To understand the current situation, which is characterized by rapid increases in population, it is necessary to understand the history of population trends. Rapid growth is a comparatively recent phenomenon. Looking back at the 8,000 years of demographic history, we find that populations have been virtually stable or growing very slightly for most of human history. For most of our ancestors, life was hard, often nasty, and very short. There was high fertility in most places, but this was usually ba
A. There might be an increase of 2.2 billion persons from 1975 to the year 2000.
B. About 50,000 babies are born annually at present.
C. Between 8000 B.C. and the present, the population increase is about 80,000,000 persons each year.
D. The population increased faster between 8000 B.C. and 1650 than between 1650 and the present.