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  • 胰腺

    lesson content

    A Shot in the Arm
    ::手臂中枪

    Giving yourself an injection can be difficult, but for someone with , it may be a matter of life or death. The person in the photo has diabetes and is injecting himself with insulin , the that helps control the level of glucose in the . Insulin is produced by the pancreas.
    ::给自己注射注射可能很困难,但对于有生命或死亡的人来说,这可能是个生死攸关的问题。 照片中的人患有糖尿病,并注射胰岛素,这有助于控制体内的葡萄糖水平。胰岛素是由胰岛素生产的。

    Introduction to the Pancreas
    ::潘克里亚斯会议介绍

    The pancreas is a large gland located in the upper left abdomen behind the stomach , as shown in the figure . The pancreas is about 15 cm (6 in) long, and it has a flat, oblong shape. Structurally, the pancreas is divided into a head, body, and tail. Functionally, the pancreas serves as both an endocrine gland and an exocrine gland.
    ::胰腺是一个大腺,位于腹部的左上方腹部,如图所示。胰腺长约15厘米(6英寸),长,具有平面、斜面形状。在结构上,胰腺分为头部、身体和尾部。在功能上,胰腺既是内分泌腺,又是排泄腺。

    • As an endocrine gland, the pancreas is part of the . As such, it releases hormones (such as insulin) directly into the bloodstream for transport to throughout the body.
      ::作为内分泌腺,胰腺是该物质的一部分。因此,它将荷尔蒙(如胰岛素)直接释放到血液中,以便输送到全身。
    • As an exocrine gland, the pancreas is part of the . As such, it releases digestive into ducts that carry the enzymes to the gastrointestinal tract , where they assist with digestion . In this concept, the focus is on the pancreas as an endocrine gland. You can read about the pancreas as an exocrine gland in the chapter Digestive System .
      ::作为分泌腺,胰腺是该物质的一部分。因此,它将消化剂释放到将酶携带到胃肠道的管道中,这些酶可以帮助消化。在这个概念中,重点是将胰腺作为内分泌腺。你可以在《消化系统》的章节中把胰腺看成是分泌腺。
    lesson content
    The pancreas is located behind the stomach and near the upper part of the small intestine (duodenum). Its ducts carry digestive enzymes into the small intestine. The endocrine hormones it produces are secreted into the blood.

    The Pancreas as an Endocrine Gland
    ::作为内分泌腺的潘克里亚

    The tissues within the pancreas that have an endocrine role exist as clusters of cells called pancreatic islets. They are also called the islets of Langerhans. You can see pancreatic tissue, including islets, in the figure . There are approximately three million pancreatic islets, and they are crisscrossed by a dense network of capillaries. The capillaries are lined by layers of islet cells that have direct contact with the , into which they secrete their endocrine hormones.
    ::具有内分泌作用的胰腺内部组织作为称为胰岛素的细胞群存在。它们也被称为兰格汉斯岛。您可以看到包括小岛在内的胰岛素组织。在图中,大约有300万个胰岛素小岛,它们被一个密集的辣椒网络环绕。卷心菜被与内分泌激素直接接触的多层小类小类细胞围住,它们将内分泌激素藏在其中。

    lesson content
    This figure shows the anatomy of the pancreas. The inset diagram in the figure shows pancreatic islet cells that produce endocrine hormones. It also shows the cells (called acinar cells) that secrete exocrine substances involved in digestion into pancreatic ducts.

    The pancreatic islets consist of four main types of cells, each of which secretes a different endocrine hormone. A ll of the hormones produced by the pancreatic islets, however, play crucial roles in glucose metabolism and the regulation of blood glucose levels, among other functions.
    ::胰岛素由四种主要细胞组成,每种细胞都分泌不同的内分泌激素,但是,除其它功能外,由胰岛素产生的所有荷尔蒙在葡萄糖新陈代谢和血糖水平调控方面起着关键作用。

    1. Islet cells called alpha (α) cells secrete the hormone glucagon . The function of glucagon is to increase the level of glucose in the blood. It does this by stimulating the liver to convert stored glycogen into glucose, which is released into the bloodstream.
      ::被称为 Alpha (α) 的岛屿细胞将荷尔蒙凝胶分泌为甲状腺细胞。 glucagon 的作用是提高血液中的葡萄糖含量。 它通过刺激肝脏将储存的甘油转化为葡萄糖,并释放到血液中。
    2. Islets cells called beta (β) cells secrete the hormone insulin. The function of insulin is to decrease the level of glucose in the blood. It does this by promoting the absorption of glucose from the blood into fat, liver, and cells. In these tissues, the absorbed glucose is converted into glycogen, fats (triglycerides), or both.
      ::胰岛素的作用是降低血液中的葡萄糖含量。通过促进将血液中的葡萄糖吸收到脂肪、肝脏和细胞中来做到这一点。在这些组织中,吸收的葡萄糖被转化成甘油、脂肪(甘油脂)或两者兼而有之。
    3. Islet cells called delta (δ) cells secrete the hormone somatostatin. This hormone is also called growth hormone inhibiting hormone, because it inhibits the anterior lobe of the pituitary gland from producing growth hormone. Somatostatin also inhibits the secretion of pancreatic endocrine hormones and pancreatic exocrine enzymes.
      ::荷尔蒙也被称为抑制荷尔蒙的生长激素荷尔蒙,因为它抑制了低垂腺前额叶产生生长激素。 Somatostatatin也抑制了胰腺内分泌内分泌激素和胰腺外泌酶的分泌。
    4. Islet cells called gamma (γ) cells secrete the hormone pancreatic polypeptide . The function of pancreatic polypeptide is to help regulate the secretion of both endocrine and exocrine substances by the pancreas.
      ::被称为伽马(γ)细胞的马岛细胞将荷尔蒙胰腺聚虫化物分泌为分泌物,胰腺聚虫化物的作用是帮助调节胰腺分泌内分泌物和外泌物。

    Disorders of the Pancreas
    ::Pancreas病症

    There are a variety of disorders that affect the pancreas. They include pancreatitis, pancreatic , and diabetes mellitus.
    ::影响胰腺的疾病多种多样,包括胰腺炎、胰腺炎和糖尿病。

    Pancreatitis
    ::胰炎

    Pancreatitis is inflammation of the pancreas. It has a variety of possible causes, including gallstones, chronic alcohol use, infections (such as measles or mumps), and certain medications. Pancreatitis occurs when digestive enzymes produced by the pancreas damage the gland’s tissues, which causes problems with fat digestion. The disorder is usually associated with intense pain in the central abdomen, and the pain may radiate to the back. Yellowing of the skin and whites of the (see image ), which is called jaundice, is a common sign of pancreatitis. People with pancreatitis may also have pale stools and dark urine . Treatment of pancreatitis includes administering drugs to manage pain, and addressing the underlying cause of the disease, for example, by removing gallstones.
    ::胰腺炎是胰腺炎,有多种可能的原因,包括胆石、慢性酒精使用、感染(如麻疹或腮腺炎)和某些药物。胰腺炎发生在胰腺组织受到胰腺组织损伤的消化酶时,造成脂肪消化问题。这种病症通常与中腹部的剧烈疼痛有关,疼痛可能向背部辐射。皮肤和白皮肤(见图象)的黄化(见图象)是胰腺炎的常见症状。患有胰腺炎的人也可能有苍白的凳子和阴暗的尿。治疗胰腺炎包括使用药物来控制疼痛,以及解决疾病的根本原因,例如,通过去除石膏。

    lesson content
    Jaundice, or yellowing of the skin and whites of the eyes, is a common sign of pancreatitis.

    Pancreatic Cancer
    ::胰腺癌

    There are several different types of pancreatic cancer that may affect either the endocrine or the exocrine tissues of the gland. Cancers affecting the endocrine tissues are all relatively rare. However, their incidence has been rising sharply. It is unclear to what extent this reflects increased detection, especially through medical imaging techniques. Unfortunately, pancreatic cancer is usually diagnosed at a relatively late stage when it is too late for surgery, which is the only way to cure the disorder. In the United States, pancreatic cancer is the fourth most common cause of deaths due to cancer.
    ::有几种不同种类的胰腺癌可能影响到内分泌或腺的排泄物组织,影响内分泌组织的癌症都相对较少,但发病率却在急剧上升,这在多大程度上反映了检测的增加,特别是通过医学成像技术。 不幸的是,由于外科手术为时太晚,因此诊断出胰腺癌的时间通常较晚,而外科手术是治愈这种疾病的唯一办法。 在美国,胰腺癌是癌症导致死亡的第四大常见原因。

    Pancreatic cancer is rare before the age of 40, and occurs most often after the age of 60. Factors that increase the risk of developing pancreatic cancer include smoking, chronic pancreatitis, and diabetes. About one in four cases of pancreatic cancer are attributable to smoking. Certain rare genetic conditions are also risk factors for pancreatic cancer.
    ::40岁前患胰腺癌是罕见的,最经常发生在60岁之后,增加患胰腺癌风险的因素包括吸烟、慢性胰腺炎和糖尿病,大约四分之一的胰腺癌病例是吸烟造成的,某些罕见的遗传条件也是患胰腺癌的危险因素。

    Diabetes Mellitus
    ::糖尿病

    By far the most common type of pancreatic disorder is diabetes mellitus, more commonly called simply diabetes. There are many different types of diabetes, but diabetes mellitus is the most common. It occurs in two major types, type 1 diabetes and type 2 diabetes . The two types have different causes and may also have different treatments, but they generally produce the same initial symptoms, which include excessive urination and thirst. These symptoms occur because the excrete more urine in an attempt to rid the blood of excess glucose. Loss of in urine stimulates greater thirst. Other signs and symptoms of diabetes are listed in the figure .
    ::最常见的胰腺紊乱类型是糖尿病,更常见地称为简单的糖尿病,有多种不同类型的糖尿病,但糖尿病最为常见,主要有两种类型,即1型糖尿病和2型糖尿病,两种类型有不同的原因,也可能有不同的治疗方法,但通常会产生相同的最初症状,包括过度的尿道和口渴。这些症状之所以出现,是因为尿液的排出量增加,是为了清除过多的葡萄糖的血液。尿液的流失刺激了更大的口渴。图中列出了糖尿病的其他症状和症状。

    lesson content
    This chart shows symptoms shared by both type 1 and type 2 diabetes in black and symptoms more common in type 1 diabetes in blue.

    When diabetes is not well controlled, it is likely to have several serious long-term consequences. Most of these consequences are due to damage to small blood vessels caused by high glucose levels in the blood. Damage to blood vessels, in turn, may lead to increased risk of coronary artery disease and stroke . Damage to blood vessels in the retina of the eye can result in gradual loss and blindness. Damage to blood vessels in the kidneys can lead to chronic kidney disease, sometimes requiring dialysis or kidney transplant. Long-term consequences of diabetes may also include damage to the nerves of the body, known as diabetic neuropathy. In fact, this is the most common complication of diabetes. Symptoms of diabetic neuropathy may include numbness, tingling, and pain in the extremities.
    ::当糖尿病没有得到很好的控制时,它可能产生若干严重的长期后果,这些后果大多是由于血液中高血糖含量对小血管造成的损害;对血管的损害反过来又可能导致冠状动脉疾病和中风的更大风险;对眼睛视网膜的血管损害可导致逐渐丧失和失明;对肾脏血管的损害可导致慢性肾脏疾病,有时需要透析或肾移植;糖尿病的长期后果还可能包括对身体神经的损害,被称为糖尿病神经病;事实上,这是糖尿病最常见的并发症;糖尿病神经病的症状可能包括麻痹、发痒和极端疼痛。

    Type 1 Diabetes
    ::1型1型糖尿病

    Type 1 diabetes is a chronic autoimmune disorder in which the immune system attacks the insulin-secreting beta cells of the pancreas. As a result, people with type 1 diabetes lack the insulin needed to keep blood glucose levels within the normal range. Type 1 diabetes may develop in people of any age, but is most often diagnosed before . For type 1 diabetics, insulin injections are critical for survival.
    ::1型糖尿病是一种慢性自动免疫紊乱,免疫系统在这种紊乱中攻击胰岛素保密的胰岛素乙型细胞,因此,1型糖尿病患者缺乏将血糖浓度保持在正常范围内所需的胰岛素。1型糖尿病可能在任何年龄的人中发作,但最常在1型糖尿病之前被诊断出来。对于1型糖尿病人来说,注射胰岛素对于生存至关重要。

    Type 2 Diabetes
    ::2型2型糖尿病

    Type 2 diabetes is the single most common form of diabetes. The cause of high blood glucose in this form of diabetes usually includes a combination of insulin resistance and impaired insulin secretion. Both genetic and environmental factors play roles in the of type 2 diabetes. Type 2 diabetes can be managed with  changes in diet and physical activity, which may increase insulin sensitivity and help reduce blood glucose levels to normal ranges. Medications may also be used as part of the treatment, as may insulin injections.
    ::2型糖尿病是最常见的单一糖尿病形式,这种形式的糖尿病的高血糖原因通常包括胰岛素抗药性和胰岛素分泌受损,遗传和环境因素在2型糖尿病中都起着作用,2型糖尿病可以通过饮食和体育活动的变化加以管理,这可能增加胰岛素的敏感性,帮助将血糖水平降低到正常范围,药物也可以作为治疗的一部分,如胰岛素注射。

    Feature: Human Biology in the News
    ::特著:《新闻》中的人类生物学

    Some patients with type 1 diabetes have been given pancreatic islet cells transplants from other human donors. If the transplanted cells are not rejected by the recipient’s immune system, they can cure the patient of diabetes. However, because of a shortage of appropriate human donors , only about one thousand  such surgeries have been performed over the past ten years.
    ::一些1型糖尿病患者接受了其他人类捐赠者的胰岛素细胞移植手术。 如果移植的细胞不被接受者的免疫系统拒绝,他们就能治愈糖尿病患者。 但是,由于缺少合适的人脉捐赠者,过去十年来只有大约一千次这样的手术。

    In June of 2016, a research team led by Dr. David K.C. Cooper at the Thomas E. Starzl Transplantation Institute in Pittsburgh, Pennsylvania, reported on their work developing pig islet cells for transplant into human diabetes patients. The researchers genetically engineered the pig islet cells to be protected from the human immune response . As a result, patients receiving the transplanted cells would require only minimal suppression of their immune system after the surgery. The pig islet cells would also be less likely to transmit pathogenic agents, because the could be raised in a controlled environment.
    ::2016年6月,在宾夕法尼亚匹兹堡Thomas E. Starzl移植研究所由David K.C. Cooper博士率领的研究小组报告了他们开发猪胎细胞以便移植到人类糖尿病患者的工作情况。研究人员对猪胎细胞进行了基因改造,以保护其不受人类免疫反应的影响。因此,接受移植细胞的病人只需在手术后对其免疫系统进行最低限度的抑制。猪胎细胞也不太可能传播病原体,因为这种细胞可以在受控制的环境中生长。

    The researchers have successfully transplanted the pig islet cells into monkey models of type 1 diabetes. As of June 2016, the scientists were looking for funding to undertake clinical trials in humans with type 1 diabetes. Dr. Cooper predicted then that if the human trials go as well as expected, the pig islet cells could be available for curing patients in as little as two years.
    ::研究人员成功地将猪胎细胞移植到1型糖尿病的猴子模型中。 截至2016年6月,科学家们正在寻找资金,以便在1型糖尿病的人类中进行临床试验。 库珀博士预测,如果人类试验如预期的那样顺利进行,猪胎细胞可以在两年内用于治疗病人。

    Summary
    ::摘要

    • The pancreas is a gland located in the upper left abdomen behind the stomach that functions as both an endocrine gland and an exocrine gland. As an endocrine gland, the pancreas releases hormones (such as insulin) directly into the bloodstream. As an exocrine gland, the pancreas releases digestive enzymes into ducts that carry them to the gastrointestinal tract.
      ::胰腺是位于腹部上左下腹部的腺,既是内分泌腺,又是排泄腺。作为内分泌腺,胰腺将荷尔蒙(如胰岛素)直接释放到血液中。作为外分泌腺,胰腺将消化酶释放到将它们输送到胃肠道的管道中。
    • Tissues in the pancreas that have an endocrine role exist as clusters of cells called pancreatic islets. The islets consist of four main types of cells, each of which secretes a different endocrine hormone. Alpha (α) cells secrete glucagon, beta (β) cells secrete insulin, delta (δ) cells secrete somatostatin, and gamma (γ) cells secrete pancreatic polypeptide.
      ::具有内分泌作用的胰腺组织作为称为胰岛素的细胞群存在,由四大类细胞组成,其中每种细胞都分泌不同的内分泌激素。阿尔法(α)细胞秘密格鲁卡贡、贝塔(β)细胞秘密胰岛素、三角洲()细胞秘密索马托斯特丁和伽马(γ)细胞秘密聚苯酯。
    • The endocrine hormones secreted by the pancreatic islets all play a role, either directly or indirectly, in glucose metabolism and homeostasis of blood glucose levels. For example, insulin stimulates the uptake of glucose by cells and decreases the level of glucose in the blood, whereas glucagon stimulates the conversion of glycogen to glucose and increases the level of glucose in the blood.
      ::内分泌激素由胰岛素分泌小盘秘而不宣,在葡萄糖新陈代谢和血液葡萄糖水平的软体保持中,都直接或间接地起到作用,例如,胰岛素刺激细胞吸收葡萄糖,降低血液中的葡萄糖水平,而葡萄干激素则刺激将甘醇转化为葡萄糖,并提高血液中的葡萄糖水平。
    • Disorders of the pancreas include pancreatitis, pancreatic cancer, and diabetes mellitus. Pancreatitis is painful inflammation of the pancreas that has many possible causes. Pancreatic cancer of the endocrine tissues is rare, but increasing in frequency. It is generally discovered too late to cure surgically. Smoking is a major risk factor for pancreatic cancer.
      ::胰腺紊乱包括胰腺炎、胰腺癌和糖尿病。胰腺炎是造成许多可能原因的胰腺疼痛炎。内分泌组织中的胰腺癌非常罕见,但频率却在增加。一般发现手术治疗为时已晚。吸烟是胰腺癌的一个主要风险因素。
    • Diabetes mellitus is the most common type of pancreatic disorder. In diabetes, inadequate activity  of insulin results in high blood levels of glucose. Type 1 diabetes is a chronic autoimmune disorder in which the immune system attacks the insulin-secreting beta cells of the pancreas. Type 2 diabetes is usually caused by a combination of insulin resistance and impaired insulin secretion due to a variety of environmental and genetic factors.
      ::糖尿病是最常见的胰腺紊乱类型,在糖尿病中,胰岛素活性不足导致高血糖含量,1型糖尿病是一种慢性自动免疫性疾病,免疫系统在这种疾病中攻击胰岛素保密的胰岛素乙型细胞,2型糖尿病通常是由胰岛素抗药性和因各种环境和遗传因素导致的胰岛素分泌受损综合作用造成的。

    Review
    ::回顾

    1. Describe the structure and location of the pancreas.
    ::1. 描述胰腺的结构和位置。

    2. Distinguish between the endocrine and exocrine functions of the pancreas.
    ::2. 区分胰腺的内分泌功能和排泄功能。

    3. Identify the four types of pancreatic islet cells, as well as the endocrine hormone that each type of cell produces.
    ::3. 确定四种类的胰岛素细胞,以及每种类细胞产生的内分泌激素。

    4. What is pancreatitis? What are possible causes and effects of pancreatitis?
    ::4. 什么是胰腺炎?什么是胰腺炎?什么是胰腺炎的可能原因和影响?

    5. Describe the incidence, prognosis, and risk factors of cancer of the endocrine tissues of the pancreas.
    ::5. 描述胰腺内分泌组织癌症的发病率、预测和风险因素。

    6. Compare and contrast type 1 and type 2 diabetes.
    ::6. 比较和对比1型糖尿病和2型糖尿病。

    7. If the alpha islet cells of the pancreas were damaged to the point that they no longer functioned, how would this affect blood glucose levels? Assume that no outside regulation of this system is occurring and explain your answer. Further, w ould administration of insulin be more likely to help or hurt this condition? Explain your answer.
    ::7. 如果胰腺的甲型小盘细胞损坏到不再起作用的程度,这将如何影响血糖水平?假设这个系统的外部管制没有发生,并解释你的答复;此外,胰岛素管理更可能帮助或伤害这种病情吗?解释你的回答。

    8. Explain how the pancreas is, to some extent, able to regulate the production of its own endocrine hormones.
    ::8. 解释胰腺如何在某种程度上能够调节其自身内分泌激素的生产。

    9. True or False:  There are two pancreases in the human body, one on the left side and one on the right.
    ::9. 真实或假:人体中有两个无脊椎动物,一个在左侧,一个在右侧。

    10. True or False:  The pancreas is part of both the digestive system and the endocrine system.
    ::10. 真实或假:胰腺是消化系统和内分泌系统的一部分。

    11. Give an example of how the pancreas can regulate the production of hormones from the pituitary gland.
    ::11. 举一个例子,说明胰腺可如何调节脊椎腺激素的生产。

    12. Which is the most common form of diabetes mellitus?
    ::12. 哪种是最常见的糖尿病形式?

    13. Explain why diabetes causes excessive thirst.
    ::13. 解释为何糖尿病导致过度口渴。

    14. Damage to __________  is the underlying cause of many of the long-term consequences of diabetes.
    ::14. 对...的损害是糖尿病许多长期后果的根本原因。

    a. the adrenal gland
    ::a. 肾上腺

    b. gamma islet cells
    ::b. 伽马同位素电池

    c. blood vessels
    ::c. 血管

    d. the pituitary gland
    ::d. 脑下腺

     Explore More
    ::探索更多

    You can learn more about pancreatic cancer by watching this video:  
    ::更多有关胰腺癌的知识,

    Check out this video to learn more about type 2 diabetes in children:
    ::校对:Portnoy