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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 SemestersFemale Reproductive SystemFertilizationThe Appearance of SomitesFirst TrimesterSecond TrimesterThird TrimesterFetal 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 HemispheresEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
November 11, 2011--------News Archive

Pre-birth Brain Growth Problems Linked to Autism
A small, preliminary study provides direct evidence for possible prenatal causes of autism.

Poor 1st, 3rd Trimester Sleep Linked to Early Births
Improving mother’s sleep habits through early intervention could reduce risk.

November 10, 2011--------News Archive

Possible New Target for Treating Kids' Liver Disease
An unexpected discovery in an often lethal pediatric liver disease may lead to a new therapy for the hard-to-treat condition.

Diagnoses of Autism Spectrum Disorders Vary Widely
Study suggests common diagnostic subcategories like asperger syndrome are flawed are of questionable value.

November 9, 2011--------News Archive

Single Protein Causes Varicose Veins
Scientists have developed a model for studying varicose veins. Their hope is that drugs can be developed to decelerate or even prevent new varicose veins.

"Switching On/Off" of Brain Genes Throughout Life
The “switching on” or expression of specific genes in the human makes each human being unique. The On/Off switching of brain cells continues throughout life.

Balancing Male and Female X Genes
Cells use 'mathematics' to equalize the loss of an X chromosome gene in males.

November 8, 2011--------News Archive

MRI Reveals Injuries in Developing Brain
New research supports the potential of high-field MRI for early identification of tiny brain injuries in the preterm infant.

Epigenetic Signatures of Autism
Analysis reveals overlap between genetic and epigenetic risk maps in autism.

November 7, 2011--------News Archive

"Cat Litter" Disease Alters Brain Chemistry
Infection by the brain parasite Toxoplasma gondii, directly affects the production of dopamine in the brain.

Two Molecules That Kill Lymphoma Cells In Mice
Two molecules have been identified that may be more effective as lymphoma cancer killers than anything currently available on the market.

Why Some Children Became Critically Ill in 2009 Flu
The largest study to date finds that kids co-infected with MRSA had an increased death risk of 8-fold. Flu vaccination is strongly urged!

WHO Child Growth Charts

In a study published in the journal Nature Genetics, scientists including University of North Carolina (UNC) biologist Jason Lieb, PhD, (also a member of UNC Lineberger Comprehensive Cancer Center), presents experiments that support a longstanding idea of how males survive with only one copy of the X chromosome.

Their work clarifies a hotly debated topic in science while providing biologists with more information on how to interpret experiments involving genetic measurements in males and females.

"The issue is important because many diseases are tied to defects in regulatory mechanisms within the cell," said Lieb.

Women have two X chromosomes, while men have one X and one Y. The lack of a 'back up' copy of the X chromosome in males contributes to many disorders that have long been observed to occur more often in males. Disorders such as hemophilia, Duchene muscular dystrophy, and certain types of color blindness.

Having only one copy of X and two copies of every other chromosome also creates a more fundamental problem – with any other chromosome, the gene number imbalance would be lethal. How can males survive with only one X?

Biologists have been debating how organisms and cells manage the imbalance between X and Y chromosomes for years, with the dominant theory being that both sexes up-regulate (or increase) the expression of X-linked genes, essentially doubling their expression to "2X" in males and "4X" in females.

Then, to correct the imbalance that now appears in females (since they have the equivalent of "4" Xs now and 2 of every other chromosome), females then 'turn off' one of the hyperactive X chromosomes, resulting in a balanced "2X" expression of those genes in both sexes.

The advent of new technology has given scientists more accurate ways to measure gene expression, and some results published in the last few years do not support the idea that X chromosomes up-regulate.

So Lieb and his colleagues re-analyzed data used in previous studies, added findings from new data and found that the up-regulation hypothesis is correct – but with some interesting twists across species.

In mammals, both males and females up-regulate (or increase) X chromosome gene expression - which females then equalize by turning off one of those X chromosomes.
In roundworms (C. elegans), both female X chromosomes stay active but then both X genes are down-regulated by half to compensate.
In fruit files (Drosophilia melanogaster), the X is increased in male chromosome genes, but not in females.

"There are several ways to get the same result and we are seeing how the dosage-balancing mechanism works in different species," says Lieb.

"We also found that not all X-linked genes are dosage compensated to the same degree– adding another layer of complexity for scientists who study gene regulation."

Other members of the research team include Christine Disteche, Robert Waterston, Jay Shendure, Di Kim Nguyen, Joseph Hiatt, and Xinxian Ding from the University of Washington; Brian Oliver, and David Sturgill, from the National Institute of Diabetes and Digestive and Kidney Disease, Thomas Gingeras, Carrie Davis, and Felix Schlesinger, from Cold Spring Harbor Laboratory, Valerie Reinke, from Yale University; LaDeana Hillier, from Washington University in St. Louis, and Sevinc Ercan from New York University.

The research was funded by the National Institutes of Health, the William H. Gates III Endowed Chair of Biomedical Sciences at the University of Washington and a fellowship from the Achievement Rewards for College Scientists.

Original article: http://www.med.unc.edu/