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Systemic circulation carries oxygenated blood from the left ventricle, through the arteries, to the capillaries in the tissues of the body. From the tissue capillaries, the deoxygenated blood returns through a system of veins to the right atrium of the heart.
The deep veins play a significant role in propelling blood toward the heart. The one-way valves in deep veins prevent blood from flowing backward, and the muscles surrounding the deep veins compress them, helping force the blood toward the heart, just as squeezing a toothpaste tube ejects toothpaste.
It then spreads down the bundle of his and then purkinje fibres to cause ventricular contraction. So when viewing the heart from the front, the direction of depolarisation is 11 o'clock to 5 o'clock. The general direction of depolarisation is known as the cardiac axis.
Ehlers-Danlos syndrome is a group of disorders that affect the connective tissues that support the skin, bones, blood vessels, and many other organs and tissues. Defects in connective tissues cause the signs and symptoms of Ehlers-Danlos syndrome, which vary from mildly loose joints to life-threatening complications. Previously, there were more than 10 recognized types of Ehlers-Danlos syndrome, differentiated by Roman numerals. In 1997, researchers proposed a simpler classification that reduced the number of major types to six and gave them descriptive names: the classical type (formerly types I and II), the hypermobility type (formerly type III), the vascular type (formerly type IV), the kyphoscoliosis type (formerly type VIA), the arthrochalasia type (formerly types VIIA and VIIB), and the dermatosparaxis type (formerly type VIIC). This six-type classification, known as the Villefranche nomenclature, is still commonly used. The types are distinguished by their signs and symptoms, their underlying genetic causes, and their patterns of inheritance. Since 1997, several additional forms of the condition have been described. These additional forms appear to be rare, affecting a small number of families, and most have not been well characterized.
Cerebral palsy refers to brain damage that occurs before a child is five years old. Therefore, adults cannot develop cerebral palsy. However, cerebral palsy does not get better or worse with age, so when a child has the condition, he or she will continue to have the condition into adulthood.
The fovea was moved 425 to 1,700 microm (965+/-262 microm) superiorly or inferiorly. Follow-up time was 2 to 12 months (median 8 months). Complications included macular pucker (3 eyes), subfoveal hemorrhage (2 eyes), macular hole (1 eye), and progression of cataract in phakic eyes (3 eyes). Thirteen of 20 eyes showed various degrees of proliferative vitreoretinopathy with epiretinal membrane formation over the inferior peripheral retina with the inferior retinal detachment stabilized by the silicone oil. One eye progressed to phthisis bulbi. Initial visual acuity ranged from 20/80 to 20/800 (median 20/150) and final visual acuity ranged from light perception to 20/200 (median 20/1000).
Surgery is an elective procedure done in people who have had extensive testing to decide if they are potential candidates. The following criteria are considered when determining if a person may be a good candidate for surgery. Person has failed adequate trials of two first-line seizure medicines (ones that are commonly effective in controlling the type of seizures the person is experiencing) and one combination of at least two drugs. A trial of a medication is considered adequate when it has been increased gradually to the maximum dosage that does not cause serious side effects. If the person has frequent seizures, any improvement will be obvious after a short time. If the seizures generally occur far apart, however, it may take months to determine whether a medication is helping. At some epilepsy centers, patients are offered additional conventional or experimental medications before surgery is considered. But research suggests that each time a trial of medication fails to control a person's seizures, it becomes less likely that a different medicine or combination will be successful. Since uncontrolled seizures present serious physical risks and social and psychological consequences, the trend these days is to proceed with surgery much sooner than in the past if it seems appropriate for that person.
Phencyclidine (PCP) was developed in the 1950s as an intravenous anesthetic but, due to the side effects of confusion and delirium, its development for human medical use was discontinued. In its pure form, it is a white crystalline powder that readily dissolves in water or alcohol and has a distinctive bitter chemical taste. On the illicit drug market, Phencyclidine contains a number of contaminants as a result of makeshift manufacturing, causing the color to range from tan to brown, and the consistency to range from powder to a gummy mass. It is available in a variety of tablets, capsules, and colored powders, which are either taken orally or snorted. The liquid form of phencyclidine is actually phencyclidine base dissolved most often in ether, a highly flammable solvent. For smoking, phencyclidine is typically sprayed onto leafy material such as mint, parsley, oregano, or marijuana.
Your body needs bile, but if it has too much cholesterol in it, that makes gallstones more likely. It can also happen if your gallbladder can't empty properly. Pigment stones are more common in people with certain medical conditions, such as cirrhosis (a liver disease) or blood diseases such as sickle cell anemia.
Very small currents can be imperceptible. Larger current passing through the body may make it impossible for a shock victim to let go of an energized object. Still larger currents can cause fibrillation of the heart and damage to tissues. Death caused by an electric shock is called electrocution.
Here is how surgeons perform knock knee correction surgery. Titanium plate is used to stabilize the affected area. The femur is cut nearly through to help with the stability. Spreaders angle the cut align the leg. The plate is secured with several screws. Synthetic bone graft material is packed in the joint. The patient will be in crutches for 4 to 6 weeks.