Background The WHO has concluded that physical activity reduces the risk of numerous diseases. However, few systemic reviews have been
performed to assess the role of leisure time physical activity (LTPA) in lowering the risk of cancer in a dose-dependent manner
and furthermore the suitability of recommendation of physical activity by the WHO.
My fellow medical students, interns, residents and attendings:
I am not a medical student but an emeritus professor of Obstetrics and Gynecology at the University of Miami Miller School of Medicine, and also a voluntary faculty member at the Florida International University Herbert Wertheim College of Medicine. I have a great deal of contact with medical students and residents. During training (as student or resident), gaining confidence in one's own abilities is a very important part of becoming a practitioner. This aspect of training does not always receive the necessary attention and emphasis. Below I describe one of the events of confidence building that has had an important and lasting influence on my career as an academic physician.
I graduated from medical school in Belgium many years ago. I came to the US to do my internship in a small hospital in up state NY. I was as green as any intern could be, as medical school in Belgium at that time had very little hands on practice, as opposed to the US medical graduates. I had a lot of "book knowledge" but very little practical confidence in myself. The US graduates were way ahead of me. My fellow interns, residents and attendings were really understanding and did their best to build my confidence and never made me feel inferior.
One such confidence-building episodes I remember vividly. Sometime in the middle part of the one-year internship, I was on call in the emergency room and was called to see a woman who was obviously in active labor. She was in her thirties and had already delivered several babies before. The problem was that she had had no prenatal care at all and there was no record of her in the hospital. I began by asking her some standard questions, like when her last menstrual period had been and when she thought her due date was. I did not get far with my questioning as she had one contraction after another and she was not interested in answering. Soon the bag of waters broke and she said that she had to push. The only obvious action for me at that point was to get ready for a delivery in the emergency room. There was no time to transport the woman to the labor and delivery room.
There was an emergency delivery “pack” in the ER, which the nurses opened for me while I quickly washed my hands and put on gloves. Soon after, a healthy, screaming, but rather small baby was delivered and handed to the pediatric resident who had been called. At that point it became obvious that there was one more baby inside the uterus. Realizing that I was dealing with a twin pregnancy, I panicked, as in my limited experience during my obstetrical rotation some months earlier I had never performed or even seen a twin delivery. I asked the nurses to summon the chief resident, who promptly arrived to my great relief. I immediately started peeling off my gloves to make room for the resident to take my place and deliver this twin baby. However, after verifying that this baby was also a "vertex" without any obvious problem, he calmly stood by, and over my objections, bluntly told me “you can do it”, even though I kept telling him that this was a first for me. I delivered this healthy, screaming twin baby in front of a large number of nurses and doctors crowding the room, only to realize that this was not the end of it and that indeed there was a third baby.
Now I was really ready to step aside and let the chief resident take over. However he remained calm and again, stood by and assured me that I could handle this situation. I am not even sure how many triplets he had delivered himself as they are not too common. Baby number three appeared quickly and also was healthy and vigorous. What a boost to my self-confidence that was! I only delivered one other set of triplets later in my career and that was by C-Section. All three babies came head first. If one of them had been a breech the situation might have been quite different.
What I will never forget is the implied lesson in confidence building the chief resident gave me. I have always remembered that. In fact I have put this approach in practice numerous times when the roles were reversed later in my career as teacher. Often in a somewhat difficult situation at the bedside or in the operating room, a student or more junior doctor would refer to me to take over and finish a procedure he or she did not feel qualified to do. Many times I would reassure and encourage that person to continue while I talked him or her through it. Many of these junior doctors have told me afterwards how they appreciated this confidence building. Of course one has to be careful to balance this approach with patient safety and I have never delegated responsibility in critical situations and have often taken over when a junior doctor was having trouble.
Those interested, can read more about my experiences in the US and a number of other countries, in a free e book, entitled "Crosscultural Doctoring. On and Off the Beaten Path" can be downloaded at this link.
I'd like to tell you a curious story. Jane was a 52 year old woman in need of a kidney transplant. Thankfully she had three loving sons who were all very happy to give her one of theirs. So Jane's doctors performed tests to find out which of the three boys would be the best match, but the results surprised everyone. In the words of Jeremy Kyle, the DNA test showed that Jane was not the mother of two of the boys... Hang on, said Jane, child birth is not something you easily forget. They're definitely mine. And she was right. It turns out Jane was a chimera.
Chimerism is the existence of two genetically different cell lines in one organism. This can arise for a number of reasons- it can be iatrogenic, like when someone has an organ transplant, or it can be naturally occurring. In Jane's case, it began in her mum's womb, with two eggs that had been fertilised by different sperm creating two embryos. Ordinarily, they would develop into two non-identical twins. However in Jane's case the two balls of cells fused early in development creating one person with both cell lines.
Thus when doctors did the first tissue typing tests on Jane, just by chance they had only sampled the 'yellow' cell line which was responsible for one of her sons. When they went back again they found the 'pink' cell line which had given rise to the other two boys.
This particular type of human chimerism is thought to be pretty rare- there are only 30 case reports in the literature. (Though remarkably both House and CSI's Gil Grissom have encountered cases.) What happens far more frequently is fetal microchimerism- which occurs in pregnant women when cells cross the placenta from baby to mum. This is awesome because we used to think the placenta was this barrier which prevented any cells crossing over. Now we've found both cells and free floating DNA cross the placenta, and that the cells can hang around for decades after the baby was born. Why? As is often the case in medicine we're not sure but one theory is that the fetal cells might have healing properties for mum. In pregnant mice who've had a heart attack, fetal cells can travel to the mum's heart where the develop into new heart muscle to repair the damage.
Whilst we're still in the early stages of understanding why this happens, we already have a practical application. In the United States today, a pregnant woman can have a blood test which isn't looking for abnormalities in her DNA but in that of her fetus. The DNA test isn't conclusive enough to be used to diagnose genetic conditions, but it is a good screening test for certain trisomies including Down's syndrome.
Now, we started with a curious tale, so lets close with a curious fact, and one that's appropriate for Mother's Day: This exchange of cells across the placenta is a two way process. So you may well have some of your mum's cells rushing through your veins right now. In my case they're probably the ones that tell me to put on sensible shoes and put that boy down...
(FYI: This is a story I originally posted on my own blog)
This tutorial explores the function of the nephron, in particular: Filtration, Reabsorption, Secretion and Excretion. It explains explains the solutes involved and how they are processed by the nephron. It is recommended that you view the Renal Anatomy series before watching this tutorial.
This lecture covers basic eye anatomy. This is the first 6 minutes of the powerpoint, which can be viewed in its entirety at Ophthobook.com Here we discuss eyelid and external eye structures.
Pneumonia is an infection in the lungs that can be caused by a variety of different pathogens, including viruses, bacteria, fungi, and mycobacteria. Depending on the pathogen, symptoms can range in severity; this video covers the pathophysiology of a lung infection, as well as common types, clinical signs and symptoms, and treatments.