https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine/Translation_task_force/RTT/Heart
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The heart is a muscular organ in both humans and other animals, which pumpsblood through the blood vessels of thecirculatory system.[1] Blood provides the body with oxygen and nutrients, and also assists in the removal of metabolic wastes.[2] The heart is located in the middle compartment of the mediastinum in thechest.[3]
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’’’心臟’’’是一種在人類和其他動物都有的[[肌造|肌肉]][[器官]]，它的功用是推動[[循環系統]]中[[血管]]的血液[1]。血液提供身體[[氧氣]]以及[[養分]]，同時也協助身體移除{{link-en|代謝廢棄物|metabolic waste}}[2]。心臟位於[[胸部|胸]]{{link-en|中隔腔|mediastinum}}的中間部位[3]。這是一個示範句
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In humans, other mammals and birds the heart is divided into four chambers: upper left and right atria; and lower left and rightventricles.[4][5] Commonly the right atrium and ventricle are referred together as theright heart and their left counterparts as theleft heart.[6] Fish in contrast have two chambers, an atrium and a ventricle, while reptiles have three chambers.[5] In a healthy heart blood flows one way through the heart due to heart valves, which preventbackflow.[3] The heart is enclosed in a protective sac, the pericardium, which also contains a small amount of fluid. The wall of the heart is made up of three layers:epicardium; myocardium; andendocardium.[7]
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人類、其他哺乳類、鳥類的心臟可分為四個[[腔室]]：左右[[心房]]（上半部）、左右[[心室]]（下半部）[4][5]。通常右心室以及右心房會被合稱為右心，而左邊的心房與心室則被合稱為左心[6]。另一方面，魚類則有兩個腔室——一個心房、一個心室；而爬蟲類則有三個腔室[5]。在健康的心臟中，血液是透過[[心瓣]]維持單一方向的流動，並藉此避免發生{{link-en|回流|Valvular heart disease]]的問題[3]。心臟被[[心膜]]的保護性袋狀物所圍繞，在心膜中有包含少量的[[液體|心包液]]。心臟是由三層所構成：[[心外膜]]、[[心肌層]]、以及[[心內膜]][7]。
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The heart pumps blood through both circulatory systems. Blood low in oxygen from the systemic circulation enters the right atrium from the superior and inferior vena cavae and passes to the right ventricle. From here it is pumped into the pulmonary circulation, through the lungs where it receives oxygen and gives off carbon dioxide. Oxygenated blood then returns to the left atrium, passes through the left ventricle and is pumped out through theaorta to the systemic circulation−where the oxygen is used and metabolized to carbon dioxide.[2] Normally with each heartbeat, the right ventricle pumps the same amount of blood into the lungs as the left ventricle pumps out into the body. Veins transport blood to the heart, while arteries transport blood away from the heart. Veins normally have lower pressures than arteries.[2][3] The heart contracts at a rate of around 72 beats per minute, at rest.[2] Exercise temporarily increases this rate, but lowers resting heart rate in the long term, and is good for heart health.[8]
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心臟透過雙向的循環系統輸送血液。由[[循環系統]]傳來心臟的缺氧血液從[[上腔|上腔靜脈]]以及[[下腔|下腔靜脈]][[靜脈]]進入右心房再經過右心室。從此血液將被輸送到[[肺部循環系統|肺循環]]，在[[肺臟]]中血液將得到氧氣同時也排出二氧化碳。接下來，有氧血會回到左心房，經過左心室後由[[主動脈]]輸送回身體的循環系統，氧氣將會被用來進行[[新陳代謝|代謝]]後成為[[二氧化碳]][2]。通常每一次{{link-en|心跳|Cardiac cycle}}，右心室會輸出到肺部與左心室輸出到主動脈相等的血液量。[[靜脈]]運輸血液到心臟，而[[動脈]]則運輸血液離開心臟。靜脈通常[[血壓]]會比動脈血壓來得低[2][3]。心臟壓縮的速率在人休息時，大約是每分鐘72次[2]。[[運動|體能鍛煉]]會短暫的增加心跳速度，但長期而言會降低{{link-en|靜止心率|Heart_rate#Resting_heart_rate}}，同時也對心臟健康有幫助[8]。
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Cardiovascular diseases (CVD) were the most common cause of death globally in 2008, accounting for 30% of cases.[9][10]Of these deaths more than three quarters were due to coronary artery disease andstroke.[9] Risk factors include: smoking, being overweight, not enough exercise, high cholesterol, high blood pressure, and poorly controlled diabetes among others.[11]Diagnosis of CVD is often done by listeningto the heart-sounds with a stethoscope,ECG or by ultrasound.[3] Diseases of the heart are primarily treated by cardiologists, although many specialties of medicine may be involved.[10]
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