Reply to AM Zivkovic and JB German

JB Commentary

Advances in stem cell biology have clarified that a tumour is a collection of heterogeneous cell populations, and that only a small fraction of tumour cells possesses the potential to self-renew. Delta-like 1 protein (Dlk-1) is a surface antigen present on foetal hepatic stem/progenitor cells but absent from mature hepatocytes in neonatal and adult rodent liver. Using a monoclonal antibody (mAb...

JB Khadka

Why I Am Not SHY: A Reply to Tononi and Cirelli

In a recent article I reviewed an influential theory of sleep function, the "synaptic homeostasis hypothesis (SHY.)" According to SHY, sleep renormalizes synapses that are potentiated during prior wakefulness. I concluded that while SHY is a seminal theory with important implications about sleep function and the brain, its underlying mechanisms are poorly defined. In an accompanying article, th...

The Authors’ Reply

07 Trap (JB/D)

Very limited funds are available for expenditure on drugs in the public health sector in most African countries. For example, in Zimbabwe during the 1994–95 fiscal year, about US$5 was spent in the public sector on drugs and supplies per person. Ensuring the optimal use of these limited funds is one of the major challenges facing health managers. The study described in this paper aimed to evalu...