肝臓は腹部の実質臓器の中で最も大きな組織だ。今回はこの臓器について見ていきたいと思う。肝臓の機能は、栄養成分の吸収、凝固因子やアルブミンの合成、解毒機能など多岐に渡る。また、消化器臓器の中で、唯一再生機能のある臓器だ。以下の説明にもあるように、昨今肝癌は稀な疾患となってきたようだ。超音波検査が普及したことが大きな要因と思われる。苦痛がなく、比較的安い医療費で受けられるので、ぜひ受けておきたい検査のひとつだ。 |
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In this video, we will cover the function of the liver and how cancer may arise. The liver is located in the upper right at the abdominal cavity and lies directly beneath the diaphragm. It is the largest glandular organ measuring approximately 20 centimeter in length, 15 centimeter in depth and weighs around 1.5 kilograms for adults. The liver can be divided into two, a right lobe and a left lobe. Blood vessels and bile ducts also define the boundaries of 8 separate segments. The liver is the only internal organ capable of natural regeneration of lost tissue. As little as 25 percent of a liver can regenerate into a whole liver. One of its most important functions is to produce bile. This collects in bile capillaries within the liver. Some is stored in the gallbladder where it can be discharged into the duodenum and small intestines to aid digestion and break down fat. When the food is fully digested, the result in fat, sugar, protein, vitamins, minerals and all other nutrition is absorbed into the bloodstream and transported to the liver for processing. Some nutrients such as sugar are retained by the liver and released if the body requires additional energy. The liver stores a multitude of substances including iron, copper, vitamin A, D, B12 and vitamin K. It also produces coagulation factors that are critical to cessation of blood loss from damaged vessels. Due to its wide range of functions, the liver is absolutely essential for sustaining life. Another important function of the liver is cleansing blood. Liver cells break down toxic and extraneous substances found in the blood and discharge them by means of excretion or urination. Initial symptoms are often ambiguous such as weight loss, poor appetite, inflated abdomen, lethargy, discomfort in the upper abdomen, and fever. Often, a tumor has grown significantly before being discovered. Liver cancer is currently very rare. Yellowing of the skin and eyes are a clear indication of failure in the liver or gallbladder and should be examined by a doctor. A first examination involves palpating the abdominal area to check for enlargements of the liver and a blood sample is taken. Suspicious findings entail further examination. Blood tests, ultrasound and CT examination are often sufficient to determine a diagnosis. Primarily liver cancer originates either in the gallbladder or liver. However, the majority of cancer instances are a result of spreading from other organs in particular the stomach and intestines. Cancer cells can separate from the tumor and be transported by the blood stream to the liver where they can attach and establish secondary sites. If the tumor is not too large and the remaining liver tissue is healthy, surgical removal is often possible. After the excision, the liver can regenerate back to full size within a few months. |
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このビデオで、肝臓の機能と肝癌の発生様式がおおよそ理解できると思う。 |