This study will examine how quickly white blood cells called CD4 lymphocytes replicate (divide) and how long they live in both HIV-infected and non-infected people by measuring how quickly the genetic material (DNA) of cells is replicated. To do this, participants will receive infusions of glucose, a non-radioactive form of a type of sugar. Cells normally use glucose to make various products needed for cell growth and replication, including cell DNA. Measuring how much glucose cells incorporate into their DNA can provide important information about cell replication. This rate of incorporation will be examined and compared in HIV-infected people and in healthy, normal volunteers.