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Written by UrDocter
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Thursday, 28 October 2010 18:50 |
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The placenta makes intrauterine life feasible. This structure is essentially a mass of blood sinuses formed by the placental septa. Into the sinuses extend chorionic projections from the fetal portion of the placenta, each covered with an enormous number of microscopic villi containing blood capillaries. Maternal blood flows into and out of these sinuses by means of a well-channeled system of vessels derived from the uterine wall. Fetal blood is led into the villi through the two umbilical arteries and then led back through the umbilical vein. As the blood moves through the villi, nutrients are absorbed and waste products are removed.
This is largely effected through simple diffusion; that is, since the concentration of oxygen and nutrients is greater on the maternal side of the placental barrier, they diffuse from the mother to the offspring. By the same token, fetal wastes (carbon dioxide, urea, and the like) diffuse from the villi into the maternal blood, from which they are excreted by the kidneys.
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Written by dr. b3ty
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Thursday, 07 January 2010 09:36 |
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These are the most important steps that always repeated and evaluated in neonatal resuscitation: evaluation on neonatal, making decision on what will be done, and doing the chosen way. The evaluation is done based on : respiratory function, heart rate, and skin appearance, so that resuscitation begin on these condition.
Drying and suck the mucus stimulate respiratory function and if it is not adequate can continue by tactile stimulation (clapping or flicking away foot palm or stroking back, stomach, chest, and extremity of baby)
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Written by UrDocter
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Thursday, 24 December 2009 03:39 |
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The development of any sign of secondary sexual maturation at an age earlier than 2,5 standard deviations less than the expected age of pubertal onset is named by precocious puberty. These ages depend on the location or the country. In North America, 9 years for boys and 8 years for girls. Girls are more common than boys (approximately five times). Seventy percents of cause precocious puberty in girls is idiopathic. These girls are taller than their peers as children but ultimately are shorter as adults owing to the premature fusion of the long bone epiphyses.
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Last Updated on Thursday, 24 December 2009 03:48 |
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Written by UrDocter
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Thursday, 17 December 2009 22:04 |
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The onset of pubertal changes usually happen between 10 and 16 years of age. In the United states, the mean age of menarche is approximately 12,4 years. The pubertal changed is determined primarily by genetic factors, but is also influenced by geographic location, and nutrional status. During this transition, a variety of physical, endocrinologic, and psychologic changes accompany the increasing levels of sex steroids.
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Last Updated on Thursday, 17 December 2009 22:10 |
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Written by UrDocter
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Sunday, 06 December 2009 14:19 |
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Tetralogy of Fallot or TOF is the most common heart defect in children that occur due to abnormal development of the fetal heart during the first 8 week of pregnancy. TOF is one of hearth lesions in which the primary defect is an anterior deviation of the infundibular septum. The 4 abnormalities of the heart described by Fallot include the following; pulmonary stenosis, ventricular septal defect( VSD ), overriding aorta, right ventricular hypertrophy
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Last Updated on Monday, 14 December 2009 15:49 |
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