Some cells have genetic switches and gizmos that allow them to replicate almost indefinitely under appropriate hormonal and biochemical stimuli. Germ cells (sperm, eggs) and stem cells (like the hematopoietic stem cells) have this function. The important point, which the poster above alluded to, is that the process of cell division is tightly controlled. It starts and stops when demanded. Any deviation from protocol should cause immediate destruction via apoptosis.

In contrast, neoplastic cells (one subset of which includes cancer cells) do not respond to the normal start/stop signals of cell division and they escape quality control mechanisms (apoptotic signals).

Regarding graft-versus-host disease, that is more of an issue with hematopoietic (bone marrow) transplantation. The host's immune system could be an issue for a foreign graft, but this sounds more like a dialysis machine to replace the liver's function. (I have not yet read the source material.) With the prevalence of hepatitis B in the Asian population, and the desire of some countries there to show some muscle in the scientific arms race, I am not entirely surprised that some trials were conducted there.

My parents, when they report back from Asia, always tell me that their text messages are included for no extra charge. They also say that the North American handsets are about 10 years behind the Asian models in terms of function and price.

I'm an organic chemistry major who took the route into medical school.

The actual subject material of organic chemistry has no direct relationship with medicine. Nobody has ever asked me to elucidate the molecular structure of protein X and synthesize it from scratch. When I started medical school with all those bloody didactic lectures, I felt as though I was at a severe disadvantage for scoffing at the biological sciences.

However, organic chemistry is as close to the 'hard' sciences (physics, math, computing, etc.) as some (most?) biology majors get. Organic chemistry mimics the learning process of medical school. During class, you're taught maybe 10 basic principles which allow you to predict and understand how molecules interact. In the lab (I mean a real synthetic organic lab where they build molecules, not the three-hour follow-the-recipe thing), one is given the opposite situation: given this molecule, how does one arrive at a set of starting materials? It is analogous to medicine. Patients don't (usually) come to the office and say, 'Doctor, I've got a pleural effusion.' They say, 'I'm short of breath' and then you have to figure out the disease. You have to be able to work backwards.

We have a saying, "Diseases don't read textbooks." Disease can present in odd ways. The old-school doctors -- the guys who actually have read their pathology and understand their disease processes -- can figure it out. Others can't. Most of the premed kids don't give a rat's ass about mechanisms. They don't care about understanding. They're focused on getting good grades and pretending to be altruistic. They don't like organic chemistry because it is 'hard' and 'difficult to get good grades'. They don't like organic chemistry because it's simply different, and consequently mentally challenging, frustrating and sometimes incomprehensible. (And smelly.)

Guess what? Organic chemistry is a pretty good preview of what medicine is like on the wards.

And as for suggestions of 'more biochemistry', I'd have to say that I haven't noticed a lot of biochemistry involved in medicine either. Most of us have forgotten, or could only give you the most basic outlines of the active site for any drug -- and that's only if the mechanism of action for a drug is known. The last time I needed to know about the Krebs cycle was...for the MCAT, I think. I'm not even sure it showed up then. I did learn about cholesterol synthesis in an organic chemistry class...now that IS relevant to today's doctor.

With respect to research -- most people are not born researchers. Most people who work at a university-affiliated 'academic' center do research because it's a condition of their employment. Truly gifted researchers are few and far between. Organic chemistry isn't human alchemy -- it can't turn a dimwit into a genius. I suppose it could help some people learn to formulate proper hypotheses and experiments.

A proper premed curriculum, IMHO, contains a good mixture of: physical sciences (calculus, algebra, STATISTICS, physics (some basic electronics and quantum mechanics)), programming (information storage, manipulation, retrieval and general problem solving skills), chemistry (organic, analytical, and physical), anatomy and physiology, English and preferably a second language (because you need to communicate with your patients and/or lawyers), basic psychology (see point above), and perhaps some biomedical ethics/philosophy/history

After learning how to think and solve problems, learning enough molecular biology, biochemistry, microbiology, etc. to be a good doctor is a relatively minor matter.