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Treating osteoporosis with bisphosphonates, particularly for more than five years, has been linked to some side effects, including atypical femur fractures. Osteoporosis medications are supposed to prevent bone breaks. But if they are taken for too long, the opposite can happen. This video highlights what you need to know as a healthcare professional to educate patients
Gunshot wounds have become increasing common in urban cities and many such cases can lead to undesirable outcomes. While gunshot wounds to the head are considered most lethal, gunshot wounds to the chest too may be dangerous. Gunshot wound to the chest is challenging owing to the presence of vital organs like lungs, heart and their surrounding structures including major blood vessels. Gunshot wound is caused by penetration of the bullet, which travels through a projectile path after being shot from a firearm. The bullet, on hitting the chest, punctures the tissue it first encounters with, the bones or the muscular chest wall. The extent and severity of the injury depends on the characteristics of the bullet and the firearm, the position and the distance of the victim, the projectile path and the nature of the tissue penetrated.
For the first few days after giving birth, a new mother’s breasts remain soft. They will produce colostrum. Colostrum, the first milk, is available in just the right amount, and is rich in immune factors that protect newborns. Sometime during the next few days, the breasts will become full, firm, warm, and perhaps tender. When this occurs, people say: “the milk is coming in!” The scientific term for this event is: engorgement. Engorgement is normal, and lasts for various periods of time depending on the individual woman. Some women experience only a day or so of mild, easy-to-manage engorgement. For other women, engorgement may be more intense, and can last from several days to two weeks.
If it is not removed, tooth decay will begin. The acids in plaque damage the enamel covering your teeth. It also creates holes in the tooth called cavities. Cavities usually do not hurt, unless they grow very large and affect nerves or cause a tooth fracture.
An esophageal stent is a flexible mesh tube, approximately 2cm (3/4 inch) wide, and is placed through the constricted area of your esophagus (food tube) to allow food and beverages to pass from your mouth to your stomach for digestion and absorption of nutrients.
Neurotransmitter 3D Animation
on Tuesday, December 21, 2010
Neurotransmitters are endogenous chemicals which transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles clustered beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to receptors in the membrane on the postsynaptic side of the synapse. Release of neurotransmitters usually follows arrival of an action potential at the synapse, but may also follow graded electrical potentials. Low level "baseline" release also occurs without electrical stimulation. Neurotransmitters are synthesized from plentiful and simple precursors, such as amino acids, which are readily available from the diet and which require only a small number of biosynthetic steps to convert. The chemical identity of neurotransmitters is often difficult to determine experimentally. For example, it is easy using an electron microscope to recognize vesicles on the presynaptic side of a synapse, but it may not be easy to determine directly what chemical is packed into them. The difficulties led to many historical controversies over whether a given chemical was or was not clearly established as a transmitter. In an effort to give some structure to the arguments, neurochemists worked out a set of experimentally tractable rules. According to the prevailing beliefs of the 1960s, a chemical can be classified as a neurotransmitter if it meets the following conditions: * There are precursors and/or synthesis enzymes located in the presynaptic side of the synapse. * The chemical is present in the presynaptic element. * It is available in sufficient quantity in the presynaptic neuron to affect the postsynaptic neuron; * There are postsynaptic receptors and the chemical is able to bind to them. * A biochemical mechanism for inactivation is present. There are many different ways to classify neurotransmitters. Dividing them into amino acids, peptides, and monoamines is sufficient for some classification purposes. Major neurotransmitters: * Amino acids: glutamate, aspartate, D-serine, γ-aminobutyric acid (GABA), glycine * Monoamines and other biogenic amines: dopamine (DA), norepinephrine (noradrenaline; NE, NA), epinephrine (adrenaline), histamine, serotonin (SE, 5-HT), melatonin * Others: acetylcholine (ACh), adenosine, anandamide, nitric oxide, etc. In addition, over 50 neuroactive peptides have been found, and new ones are discovered regularly. Many of these are "co-released" along with a small-molecule transmitter, but in some cases a peptide is the primary transmitter at a synapse. β-endorphin is a relatively well known example of a peptide neurotransmitter; it engages in highly specific interactions with opioid receptors in the central nervous system. Single ions, such as synaptically released zinc, are also considered neurotransmitters by some[by whom?], as are some gaseous molecules such as nitric oxide (NO) and carbon monoxide (CO). These are not classical neurotransmitters by the strictest definition, however, because although they have all been shown experimentally to be released by presynaptic terminals in an activity-dependent way, they are not packaged into vesicles. By far the most prevalent transmitter is glutamate, which is excitatory at well over 90% of the synapses in the human brain. The next most prevalent is GABA, which is inhibitory at more than 90% of the synapses that do not use glutamate. Even though other transmitters are used in far fewer synapses, they may be very important functionally—the great majority of psychoactive drugs exert their effects by altering the actions of some neurotransmitter systems, often acting through transmitters other than glutamate or GABA. Addictive drugs such as cocaine and amphetamine exert their effects primarily on the dop
• Define and use related medical terminology.
• Describe and demonstrate techniques for imaging the thyroid gland.
• Discuss functional abnormalities of the thyroid gland.
• Correlate laboratory data relevant to the thyroid and parathyroid glands.
• Describe, and recognize on images, pathologies of the thyroid gland.
• Identify the anatomy of the parathyroid glands on diagrams and sonograms.
• Describe and demonstrate techniques for imaging the parathyroid glands.
• Describe, and recognize on images, pathologies of the parathyroid glands.
• List and describe other neck masses.
• Follow relevant protocols when scanning.
• Differentiate the sonographic appearances of the female reproductive organs in relation to the menstrual cycle, the use of contraceptives and hormone replacement, and following chemotherapy.
• Explain the Patient Privacy Rule (HIPAA) and Patient Safety Act (see reference).