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Hypoechoic
Echogenicity (misspelled sometimes as echogenecity) or echogeneity is the ability to bounce an echo, e.g. return the signal in ultrasound examinations. In other words, echogenicity is higher when the surface bouncing the sound echo reflects increased sound waves. Tissues that have higher echogenicity are called "hyperechogenic" and are usually represented with lighter colors on images in medical ultrasonography. In contrast, tissues with lower echogenicity are called "hypoechogenic" and are usually represented with darker colors. Areas that lack echogenicity are called "anechogenic" and are usually displayed as completely dark. Microbubbles Echogenicity can be increased by intravenously administering gas-filled microbubble contrast agent to the systemic circulation, with the procedure being called contrast-enhanced ultrasound. This is because microbubbles have a high degree of echogenicity. When gas bubbles are caught in an ultrasonic frequency field, they compress, oscillate, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichorionic Twins With Heart Activity At 8w5d Since Co-incubation
The chorion is the outermost fetal membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside the zona pellucida (in mammals), known as the vitelline membrane in other animals. In insects it is developed by the follicle cells while the egg is in the ovary.Chapman, R.F. (1998) "The insects: structure and function", Section ''The egg and embryology''. Previewed in Google Bookon 26 Sep 2009. Structure In humans and other mammals (excluding monotremes), the chorion is one of the fetal membranes that exist during pregnancy between the developing fetus and mother. The chorion and the amnion together form the amniotic sac. In humans it is formed by extraembryonic mesoderm and the two layers of trophoblast that surround the embryo and other membranes; the chorionic villi emerge from the chorion, invade the endometrium, and allow the transfer of nutrients from maternal blood to fetal blood. Laye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Liver
Fatty liver disease (FLD), also known as hepatic steatosis, is a condition where excess fat builds up in the liver. Often there are no or few symptoms. Occasionally there may be tiredness or pain in the upper right side of the abdomen. Complications may include cirrhosis, liver cancer, and esophageal varices. There are two types of fatty liver disease: non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease. NAFLD is made up of simple fatty liver and non-alcoholic steatohepatitis (NASH). The primary risks include alcohol, type 2 diabetes, and obesity. Other risk factors include certain medications such as glucocorticoids, and hepatitis C. It is unclear why some people with NAFLD develop simple fatty liver and others develop NASH. Diagnosis is based on the medical history supported by blood tests, medical imaging, and occasionally liver biopsy. Treatment of NAFLD is generally by dietary changes and exercise to bring about weight loss. In those who are severely affec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustics
Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an Acoustical engineering, acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries. Hearing (sense), Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hearing
Hearing, or auditory perception, is the ability to perceive sounds In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid. In human physiology and psychology, sound is the ''reception'' of such waves and their ''perception'' by the ... through an organ, such as an ear, by detecting Vibration, vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory science. Sound may be heard through solid, liquid, or gaseous matter. It is one of the traditional five senses. Partial or total inability to hear is called hearing loss. In humans and other vertebrates, hearing is performed primarily by the auditory system: mechanical waves, known as vibrations, are detected by the ear and transduction (physiology), transduced into nerve impulses that are perceived by the brain (primarily in the temporal lobe). Like touch, audition requires sen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasound
Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies from person to person and is approximately 20 Hertz, kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz. Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and accelerating chemical processes. Animals such as bats and porpoises use ultrasound for locating Predation, prey and obstacles. History Acoustics, the science of sound, starts as far back as Pyth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
