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Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



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Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
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Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
April 15, 2011--------News Archive

TET1 Crucial to Fetal Development and Cancer
TET1 ensures normal fetal development and is crucial when certain genes need to turn on or off during cell division.

Aging Eggs Key to Miscarriage and Birth Defects
By the time a woman is in her 40s, about half her eggs are probably chromosomally abnormal; for women in their 20s, it's probably about 10 percent.


April 14, 2011--------News Archive

Female Body Basis for Medical Autopsy/Dissection
The female body is at the heart of the development of autopsy and dissection beginning with medical practices from the middle ages.

A Measure of Cell Health - The Length of Telomeres
UCSF scientists report studies showing psychological stress leads to shorter telomeres – the protective caps on the ends of chromosomes. The findings also suggest that exercise may prevent this damage.


April 13, 2011--------News Archive

Air Polution Prenatally Linked to Behavior Problems
Mothers' exposure during pregnancy to pollutants may lead to behavioral problems in their children.

Stress In Pregnancy May Create Obesity in Child
Increasing evidence supports that pregnancies that are physically or psychologically stressed are at higher risk of producing obese offspring.


April 12, 2011--------News Archive

Umbilical Cord Stem Cells Studied for Lupus Therapy
Human umbilical cord blood stem cells found to benefit the treatment of lupus nephritis in mice with systemic lupus erythematosus.

Dopamine Controls Formation of New Brain Cells
The neurotransmitter dopamine acts as a handbreak turning off the production of stem cells forming new neurons in the adult brain.


April 11, 2011--------News Archive

Untangling The Complexity Of The Brain
There are an estimated one hundred billion nerve cells in the brain. Now scientists are moving closer to building a model of these connections and their functions.

New Treatment for Rare Recurrent Fever in Kids
A rare syndrome called periodic fever associated with aphthous stomatitis, pharyngitis and cervical adenitis — or PFAPA — is diagnosed using tools from the Human Genome Project.


WHO Child Growth Charts

Human egg surrounded by sperm
Image from BBC
Normal number of chromosomes - 23


Washington State University researchers have confirmed a critical step in cell division that results in age-related miscarriages and birth defects, including Down syndrome.

Writing in the upcoming issue of the journal Current Biology, the researchers say they recreated the conditions in which an egg cell will continue to undergo cell division without properly arranging its chromosomes, creating offspring with aneuploidy - an abnormal number of chromosomes.

Sperm cells and those from elsewhere in the body will stop dividing until chromosomes are properly lined up.

"This paper says, yes, this cell does have a different way of controlling division and that makes it inherently error prone," said Pat Hunt, a professor of molecular biosciences.

The problem is particularly acute in older women.

"We think that by the time a woman is in her 40s, about half the eggs she's ovulating are probably chromosomally abnormal," said Hunt. "And for women in their 20s, it's probably about 10 percent. So it's a huge change."

Just why age would have such a powerful effect on an egg is still unclear, says Hunt, "but it does provide us some good basic knowledge that allows us to understand why in fact the egg is so different."

Co-author graduate student So Iha Nagaoka says the finding could lead to an in-vitro fertilization "screening system" that might sort out bad eggs.

"We would also like to find the gene or genes responsible for this insensitivity, but this might be a bit of a long shot," he says.

Between 15 and 20 percent of pregnancies end in miscarriages. Most are in the first 13 weeks, and more than half of those are the result of problems with chromosomes in the fetus, according to the American College of Obstetricians and Gynecologists. Fetuses with chromosomal abnormalities are carried to term in 1 of 160 pregnancies, with Down syndrome, one of the most common aneuploid conditions, occurring in 1 in every 800 children.

The researchers set up the conditions for improper cell division using a model mouse cell. Collaborating with them were researchers from Case Western University and the University of Kansas Medical Center.

They focused on the meiotic spindle, a structure that separates and aligns chromosomes before cell division. In most cells, the so-called Spindle Assembly Checkpoint will keep a cell from dividing if all the chromosomes aren't in their place. Hunt compares it to the starting line of a race in which everyone has to be in position before the starting gun fires.

“Quite surprisingly, however, eggs seem to bend the rules, allowing the division to occur when most—but not all—chromosomes are properly positioned,” she said. “This difference in cell cycle control provides an explanation for the high error rate in human eggs.”

In an accompanying commentary, R. Scott Hawley of the Stowers Institute of Medical Research suggests that “a simple numbers game” may make eggs more tolerant of one or two misaligned chromosomes. Males produce hundreds of millions of sperm cells at a time, so there are plenty to spare if a few cells that are trying to produce sperm are prevented from dividing.

But female mammals usually produce only one egg per cycle. A failure of that egg to divide would make fertilization impossible, but continuing with one or two misplaced chromosomes at least leaves open the possibility of a viable conception, says Hawley.

“I always say the difference is not that men don’t make mistakes in making sperm,” said Hunt. “It’s just they kill those mistakes. And women are just better with living with those mistakes.”

orginal article: http://www.eurekalert.org/pub_releases/2011-04/wsu-wrc041211.php