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  • 案例研究结论:需要放松

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    Case Study Conclusion: Needing to Relax
    ::案例研究结论:需要放松

    As you learned in the beginning of this chapter, botulinum toxin — one form of which is sold under the brand name Botox — does much more than smooth out wrinkles. It can be used to treat a number of disorders involving excessive muscle contraction, including cervical dystonia. You also learned that cervical dystonia, which Edward suffers from, causes abnormal, involuntary muscle contractions of the neck. This results in jerky movements of the head and neck, and/or a sustained abnormal tilt to the head. It is often painful and can significantly interfere with a person’s life.
    ::正如你在本章开头学到的,肉毒杆菌毒素是一种以品牌 " 肉毒杆菌 " 出售的一种形式,其作用远不止是滑动皱纹,还可以用来治疗包括宫颈溃疡在内的肌肉过度收缩引起的一系列疾病。你还了解到,爱德华患有的宫颈痢疾导致颈部肌肉不自然、非自愿收缩,导致头部和颈部的干燥动作和/或头部持续不正常的倾斜。它常常令人痛苦,而且会大大干扰一个人的生活。

    How could a toxin actually help treat a muscular disorder? The botulinum toxin is produced by the soil bacterium, Clostridium botulinum , and it is the cause of the potentially deadly disease called botulism. Botulism is often a foodborne illness, commonly caused by foods that are improperly canned. Other forms of botulism are caused by wound infections, or occur when infants consume spores of the bacteria from soil or honey.
    ::一种毒素如何能真正帮助治疗肌肉疾病?肉毒杆菌毒素是由土壤细菌(Clostridium botulinum)生成的,并且是可能致命的疾病(叫做肉毒杆菌)的根源。 肉毒杆菌往往是由食物传染的疾病,通常由不适当的罐头食物造成。 其他形式的肉毒杆菌则由伤口感染造成,或者当婴儿食用土壤或蜂蜜中的细菌颗粒时发生。

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    These pickles are jokingly labeled "botulism," but actual botulism is really no joke.
    ::这些泡菜是开玩笑的 被贴上"博生主义"的标签, 但实际的博生主义真的不是笑话。

    Botulism can be life-threatening, because it paralyzes muscles throughout the body, including those involved in breathing. When a very small amount of botulinum toxin is injected carefully into specific muscles by a trained medical professional, however, it can be useful in inhibiting unwanted muscle contractions.
    ::肉毒杆菌可能会危及生命,因为它会瘫痪整个身体的肌肉,包括参与呼吸的肌肉。 但是,当一个训练有素的医学专业人员小心地将少量肉毒杆菌毒素注入特定的肌肉时,它会有助于抑制不必要的肌肉收缩。

    For cosmetic purposes, botulinum toxin injected into the facial muscles relaxes them to reduce the appearance of wrinkles. When used to treat cervical dystonia, it is injected into the muscles of the neck to inhibit excessive muscle contractions. For many patients, this helps relieve the abnormal positioning, movements, and pain associated with the disorder. The effect is temporary, so the injections must be repeated every three to four months to keep the symptoms under control.
    ::为了化妆目的,将肉毒杆菌毒素注入面部肌肉会放松它们,以减少皱纹的外观。当用来治疗宫颈痢疾时,会将它注入颈部肌肉以抑制过度肌肉收缩。对许多病人来说,这有助于缓解与病理有关的异常定位、运动和疼痛。效果是暂时的,因此必须每三至四个月重复注射一次,以控制症状。

    How does botulinum toxin inhibit muscle contraction? First, recall how skeletal muscle contraction works. A motor neuron instructs skeletal muscle fibers to contract at a synapse between them called the neuromuscular junction. A nerve impulse called an action potential travels down to the axon terminal of the motor neuron, where it causes the release of the neurotransmitter acetylcholine (ACh) from synaptic vesicles. The ACh travels across the synaptic cleft and binds to ACh receptors on the muscle fiber, signaling the muscle fiber to contract. According to the sliding filament theory, the contraction of the muscle fiber occurs due to the sliding of myosin and actin filaments across each other. This causes the Z discs of the sacromeres to move closer together, shortening the sacromeres and causing the muscle fiber to contract.
    ::肉毒毒素是如何抑制肌肉收缩的? 首先,记得骨骼肌肉收缩是如何起作用的。一个运动神经神经元指示骨骼肌肉纤维在它们之间的神经肌肉交叉点发生突触时缩缩。一个神经冲动称行动可能进入运动神经元的轴终端,这导致神经分泌剂乙酰胆碱(ACh)从合成卵蛋白释放出来。ACH穿梭于神经分泌裂口,在肌肉纤维上粘结于ACH受体,信号肌肉纤维收缩。根据滑动纤维理论,肌肉纤维的收缩是由于肌素的滑动和相互穿透而发生。这导致细胞细胞细胞的Z盘相距更近,缩短了细胞细胞细胞,并导致肌肉纤维收缩。

    If you wanted to inhibit muscle contraction, at what points could you theoretically interfere with this process? Inhibiting the action potential in the motor neuron, the release of ACh, the activity of ACh receptors, or the sliding filament process in the muscle fiber would all theoretically impair this process and inhibit muscle contraction. For example, in the disease myasthenia gravis, the function of the ACh receptors is impaired, causing a lack of sufficient muscle contraction. As you have learned, this results in muscle weakness that can eventually become life-threatening. Botulinum toxin works by inhibiting the release of ACh from the motor neurons, thereby removing the signal instructing the muscles to contract. The illustration depicts how this occurs.
    ::如果您想抑制肌肉收缩, 理论上您可以在哪一点干预这个过程? 抑制运动神经的动作潜力, 释放ACH, ACH 受体的活动, 肌肉纤维的滑动丝化过程, 都会在理论上损害这个过程, 抑制肌肉收缩。 比如, 在脑膜炎的疾病中, ACH 受体的功能受损, 导致缺乏足够的肌肉收缩。 正如您所知道的, 这导致肌肉虚弱, 最终会危及生命。 Botulinum毒素工作阻止了运动神经的ACH 释放, 从而消除了指示肌肉收缩的信号。 插图说明了这种情况是如何发生的。

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    Botulinum toxins cleave (break down) proteins (depicted here as red, blue, and green lines) that normally allow synaptic vesicles bind to the membrane of the motor neuron’s axon terminal in order to release the neurotransmitter ACh. Cleavage of these proteins prevents the synaptic vesicles from fusing to the membrane, and therefore ACh release is inhibited. In this illustration, BTX A-G refers to different subtypes of botulinum toxins.
    ::Butulinum毒素(碎裂)蛋白质(此处称为红色、蓝色和绿线)通常允许合成卵蛋与运动神经神经元轴终端的膜结合,以释放神经传感器ACH。 这些蛋白质的裂变阻止了合成卵蛋白向膜的熔化,因此ACH的释放受到抑制。 在这个示例中, BTX A-G 指不同的肉毒毒素亚型。

    Fortunately, Edward’s excessive muscle contractions and associated pain improved significantly thanks to botulinum toxin injections. Although cervical dystonia cannot currently be cured, botulinum toxin injections have improved the quality of life for many patients with this and other disorders involving excessive involuntary muscle contractions.
    ::幸运的是,由于肉毒杆菌毒素的注射,爱德华过度肌肉萎缩和相关疼痛显著改善。 尽管目前宫颈溃疡无法治愈,但肉毒杆菌毒素的注射改善了许多患有这种疾病和其他过度非自愿肌肉萎缩症的患者的生活质量。

    As you have learned in this chapter, our muscular system allows us to do things like make voluntary movements, digest our food, and pump blood through our bodies. Whether they are in your arm, heart, stomach, or blood vessels, muscle tissue works by contracting. But as you have seen here, too much contraction can be a very bad thing. Fortunately, scientists and physicians have found a way to put a potentially deadly toxin — and wrinkle-reducing treatment — to excellent use as a medical treatment for some muscular system disorders. 
    ::正如你们在本章中所学到的,我们的肌肉系统使我们能够做一些事情,比如自愿运动、消化食物和通过我们的身体抽血,不管它们是否在你的手臂、心脏、胃或血管中,肌肉组织通过收缩而起作用。但是正如你们在这里所看到的,太多的收缩可能是一件非常糟糕的事情。幸运的是,科学家和医生找到了一种方法,将一种潜在的致命毒素——以及减少皱纹的治疗——作为治疗某种肌肉系统紊乱的极佳方法。

    Chapter Summary
    ::章次摘要

    In this chapter, you learned about the muscular system. Specifically, you learned that:
    ::在本章中,你学到了肌肉系统。具体地说,你学到了:

    • The muscular system consists of all the muscles of the body. There are three types of muscle: skeletal muscle (which is attached to bones by tendons and enables voluntary body movements), cardiac muscle (which makes up the walls of the heart and makes it beat) and smooth muscle (which is found in the walls of internal organs and other internal structures and controls their movements).
      ::肌肉系统由身体的所有肌肉组成。肌肉有三种类型:骨骼肌肉(骨骼肌肉通过管子附在骨骼上,并能够使身体自愿运动)、心脏肌肉(构成心脏的墙壁并使其跳动)和光滑肌肉(在内部器官和其他内部结构的墙壁中发现,并控制其运动)。
    • Muscles are organs composed mainly of muscle cells, which may also be called muscle fibers or myocytes. Muscle cells are specialized for the function of contracting, which occurs when protein filaments inside the cells slide over one another using energy from ATP. Muscle tissue is the only type of tissue that has cells with the ability to contract.
      ::肌肉是主要由肌肉细胞构成的器官,也可以称为肌肉纤维或细胞。肌肉细胞是专门用于包扎功能的。 当细胞内蛋白丝利用ATP的能量滑向对方时,肌肉组织就会出现这种情况。肌肉组织是唯一一类组织,其细胞有能力包扎。
    • Muscles can grow larger, or hypertrophy. This generally occurs through increased use, although hormonal or other influences can also play a role. Muscles can also grow smaller, or atrophy. This may occur through lack of use, starvation, certain diseases, or aging. In both hypertrophy and atrophy, the size — but not the number — of muscle fibers changes. The size of muscles is the main determinant of muscle strength.
      ::肌肉会变大或变肥,这通常通过增加使用而发生,尽管荷尔蒙或其他影响也可以发挥作用。肌肉也可能变小或变小,也可能变小,也可能变衰老,可能因为缺乏使用、饥饿、某些疾病或衰老而发生。在肥壮和萎缩中,肌肉纤维变化的大小——而不是数量。肌肉的大小是肌肉力量的主要决定因素。
    • Skeletal muscles need the stimulus of motor neurons to contract, and to move the body, they need the skeletal system to act upon.
      ::骨骼肌肉需要电动神经元的刺激 以收缩, 并移动身体, 他们需要骨骼系统 来采取行动。
    • Skeletal muscle is the most common type of muscle tissue in the human body.  T o move bones in opposite directions, skeletal muscles often consist of pairs of muscles that work in opposition to one another to move bones in different directions at joints.
      ::骨骼肌肉是人体最常见的肌肉组织类型。 要将骨骼向相反方向移动,骨骼肌肉通常由两对肌肉组成,它们相互对立,在关节上将骨骼向不同方向移动。
    • Skeletal muscle fibers are bundled together in units called muscle fascicles, which are bundled together to form individual skeletal muscles. Skeletal muscles also have connective tissue supporting and protecting the muscle tissue.
      ::骨骼肌肉纤维以称为肌肉分册的单元捆绑在一起,这些单元被捆绑在一起形成个体骨骼肌肉,骨骼肌肉也有连接组织支持和保护肌肉组织。
      • Each skeletal muscle fiber consists of a bundle of myofibrils, which are bundles of protein filaments. The filaments are arranged in repeating units called sarcomeres, which are the basic functional units of skeletal muscles. Skeletal muscle tissue is striated, because of the pattern of sarcomeres in its fibers.
        ::每根骨骼肌肉纤维都由一捆骨髓纤维组成,它们是蛋白丝的捆包。丝丝被安排在称为沙红的重复单元中,这些单元是骨骼肌肉的基本功能单位。骨骼肌肉组织由于纤维中的沙红的形态而被撕裂。
      • Skeletal muscle fibers can be divided into two types, called slow-twitch and fast-twitch fibers. Slow-twitch fibers are used mainly in aerobic endurance activities (such as long-distance running). Fast-twitch fibers are used mainly for non-aerobic, strenuous activities (such as sprinting). Proportions of the two types of fibers vary from muscle to muscle and person to person.
        ::骨骼肌肉纤维可分为两类,称为慢动和快动纤维,慢动纤维主要用于有氧耐力活动(如长距离运行),快动纤维主要用于无氧、艰苦的活动(如冲刺),两种纤维的比例因肌肉和人而异。

      ::每根骨骼肌肉纤维都由一捆骨骼肌纤维组成,它们是蛋白丝的捆包。丝状纤维被安排在称为沙红菌的重复单元中,这是骨骼肌肉的基本功能单元。骨骼肌肉组织由于纤维中的沙红菌的形态而被撕裂。骨骼肌肉纤维可以分为两类,即慢电动和快电动纤维。慢电动纤维主要用于有氧耐力活动(如长距离运行);快速电动纤维主要用于非氧、艰苦的活动(如冲刺)。两种纤维的比例因肌肉和肌肉而异,因人而异。
    • Smooth muscle tissue is found in the walls of internal organs and vessels. When smooth muscles contract, they help the organs and vessels carry out their functions. Contractions of smooth muscles are involuntary and controlled by the autonomic nervous system, hormones, and other substances.
      ::在内脏器官和容器的墙壁上发现了肌肉组织,在肌肉组织松动时,它们会帮助器官和容器发挥功能,肌肉肌肉的腐蚀是非自愿的,由自主神经系统、荷尔蒙和其他物质控制。
      • Cells of smooth muscle tissue are not striated because they lack sarcomeres, but the cells contract in the same basic way as striated muscle cells. Unlike striated muscle, smooth muscle can sustain very long-term contractions and maintain its contractile function, even when stretched.
        ::光滑肌肉组织细胞不会因为缺乏正丙烯而减缩,而是细胞以与减速肌肉细胞相同的基本方式收缩。 与减速肌肉不同的是,光滑肌肉可以保持非常长期的收缩并保持其内脏功能,即使拉伸时也是如此。

      ::光滑肌肉组织细胞不会因为缺乏正丙烯而减缩,而是细胞以与减速肌肉细胞相同的基本方式收缩。 与减速肌肉不同的是,光滑肌肉可以保持非常长期的收缩并保持其内脏功能,即使拉伸时也是如此。
    • Cardiac muscle tissue is found only in the wall of the heart. When cardiac muscle contracts, the heart beats and pumps blood. Contractions of cardiac muscle are involuntary, like those of smooth muscles. They are controlled by electrical impulses from specialized cardiac cells.
      ::心肌组织只能在心脏的墙壁中找到。当心脏肌肉收缩时,心脏会跳动,抽动血液。心肌的萎缩是非自愿的,就像光滑肌肉一样。它们受特殊心脏细胞的电脉冲控制。
      • Like skeletal muscle, cardiac muscle is striated because its filaments are arranged in sarcomeres. T he exact arrangement, however, differs, making cardiac and skeletal muscle tissues look different from one another.
        ::与骨骼肌肉一样,心脏肌肉也因为其丝状是用石墨排列而变形,但确切的排列方式不同,使心脏和骨骼肌肉组织看起来不同。
      • The heart is the muscle that performs the greatest amount of physical work in the course of a lifetime. Its cells contain a great many mitochondria to produce ATP for energy and to help the heart resist fatigue.
        ::心脏是肌肉,在一生中做着最大量的体力工作。细胞含有大量的细胞细胞,可以产生能量ATP,帮助心脏抵御疲劳。

      ::心脏肌肉与骨骼肌肉一样,因为其丝状是用石墨排列的,因此心脏肌肉变小。但是,确切的排列方式不同,使心脏和骨骼肌肉组织看起来彼此不同。心脏是一生中从事最大体力工作的肌肉。细胞中含有大量微积分,以产生能量ATP,帮助心脏抵抗疲劳。
    • A muscle contraction is an increase in the tension or a decrease in the length of a muscle. A muscle contraction is isometric if muscle tension changes, but muscle length remains the same. It is isotonic if muscle length changes, but muscle tension remains the same.
      ::肌肉收缩是肌肉张力的加剧或肌肉长度的缩短。肌肉收缩是肌肉张力变换时的等分法,但肌肉的长度保持不变。肌肉变换时是同位素,但肌肉张力却保持不变。
      • A skeletal muscle contraction begins with electrochemical stimulation of a muscle fiber by a motor neuron. This occurs at a chemical synapse called a neuromuscular junction. The neurotransmitter acetylcholine diffuses across the synaptic cleft and binds to receptors on the muscle fiber. This initiates a muscle contraction.
        ::骨骼肌肉收缩始于运动神经元对肌肉纤维的电化学刺激,发生在称为神经肌肉交叉口的化学突触中。神经分质乙酰胆碱在突触左裂处扩散,与肌肉纤维的受体捆绑在一起。这引发肌肉收缩。
      • Once stimulated, the protein filaments within the skeletal muscle fiber slide past each other to produce a contraction. The sliding filament theory is the most widely accepted explanation for how this occurs. According to this theory, thick myosin filaments repeatedly attach to and pull on thin actin filaments, thus shortening sarcomeres.
        ::一旦被刺激,骨骼肌肉纤维内的蛋白丝就会相互滑过,以产生收缩。 滑动丝理论是最广为人接受的如何发生这种情况的解释。 根据这一理论,厚厚的肌丝反复附着和拉扯薄的纤维,从而缩短了丝状。
      • Crossbridge cycling is a cycle of molecular events that underlies the sliding filament theory. Using energy in ATP, myosin heads repeatedly bind with and pull on actin filaments. This moves the actin filaments toward the center of a sarcomere, shortening the sarcomere and causing a muscle contraction.
        ::跨桥环绕是一个分子事件的循环,它支撑着滑动丝质理论。在 ATP 中,使用能量,肌肤头反复被活性丝状物捆绑并拉动。这把丝质的活性向弧线中心移动,缩短弧线并造成肌肉收缩。
      • The ATP needed for a muscle contraction comes first from ATP already available in the cell, and more is generated from creatine phosphate. These sources are quickly used up. Glucose and glycogen can be broken down to form ATP and pyruvate. Pyruvate can then be used to produce ATP in aerobic respiration if oxygen is available, or it can be used in anaerobic respiration if oxygen is not available.
        ::肌肉收缩所需的ATP首先来自细胞中已有的ATP,更多来自丙烯磷酸酯。这些来源很快用完。可以将葡萄糖和甘油分解为ATP 和 prevate。然后,若缺氧,可使用Pyruvate在有氧呼吸中生成ATP,或者在缺氧情况下可用于厌氧呼吸。

      ::骨骼肌肉收缩始于运动神经神经对肌肉纤维的电化学刺激。 这发生在一个称为神经肌肉交叉点的化学神经突触中。 神经分泌剂乙酰胆碱酯酶横跨突突裂, 并粘结到肌肉纤维的受体上。 这引发肌肉收缩。 一旦刺激, 骨骼肌肉纤维的蛋白丝会相互滚动, 从而产生一个缩缩缩。 滑动丝丝质理论是这种情况发生时最普遍接受的解释。 根据这一理论, 厚的肌丝丝会反复附着并拉动薄的动作丝状, 从而缩短丝质丝质。 跨桥循环循环循环是一个分子事件循环, 支撑着滑动的纤维纤维纤维的受体。 在ATP中, 骨质结层会反复粘结并拉动, 将纤维纤维的纤维化作用推向一个中心, 从而可以降低丝质浓度, 并导致肌肉萎缩。 骨质丝丝结的肌肉萎缩需要先从ATP 开始从ATP 开始粘结结结, 在使用过氧基的血液中产生。
    • Physical exercise is defined as any bodily activity that enhances or maintains physical fitness and overall health. Activities such as household chores may even count as physical exercise! Current recommendations for adults are 30 minutes of moderate exercise a day.
      ::体力锻炼是指任何加强或保持身体健康和整体健康的身体活动,如家务劳动等甚至可以算作身体锻炼,目前对成年人的建议是每天30分钟的中度锻炼。
    • Aerobic exercise is any physical activity that uses muscles at less than their maximum contraction strength, but for long periods of time. This type of exercise uses a relatively high percentage of slow-twitch muscle fibers that consume large amounts of oxygen. Aerobic exercises increase cardiovascular endurance, and include cycling and brisk walking.
      ::有氧锻炼是指使用肌肉的物理活动,其收缩强度低于其最大收缩强度,但需要很长时间。这种锻炼使用相当高比例的慢动抽动肌肉纤维,消耗大量氧气。有氧锻炼会增加心血管耐力,包括循环和快速行走。
    • Anaerobic exercise is any physical activity that uses muscles at close to their maximum contraction strength, but for short periods of time. This type of exercise uses a relatively high percentage of fast-twitch muscle fibers that consume small amounts of oxygen. Anaerobic exercises increase muscle and bone mass and strength, and they include push-ups and sprinting.
      ::抗氧锻炼是指在接近最大收缩强度但短期内使用肌肉的任何体育活动。 这种锻炼使用相当高比例的快速抽动肌肉纤维,消耗少量氧气。 抗氧锻炼会增加肌肉和骨质质量和强度,包括俯卧撑和冲刺。
    • Flexibility exercise is any physical activity that stretches and lengthens muscles, thereby improving range of motion and reducing risk of injury. Examples include stretching and yoga.
      ::灵活性运动是指任何伸展和延展肌肉的体育活动,从而扩大运动范围,减少受伤风险,例如伸展和瑜伽。
    • Many studies have shown that physical exercise is positively correlated with a diversity of physical, mental, and emotional health benefits. Physical exercise also increases quality of life and life expectancy.
      ::许多研究表明,身体锻炼与身体、精神和情感健康的各种好处有着积极的关联,身体锻炼也提高了生活质量和预期寿命。
      • Many of the benefits of exercise may come about because contracting muscles release hormones called myokines, which promote tissue repair and growth and have anti-inflammatory effects.
        ::锻炼的许多好处可能来自于肌肉萎缩释放了叫“近氧”的荷尔蒙,促进组织修复和生长,并产生抗炎效果。
      • Physical exercise can reduce risk factors for cardiovascular disease, including hypertension and excess body weight. Physical exercise can also increase factors associated with cardiovascular health, such as mechanical efficiency of the heart.
        ::身体锻炼可以减少心血管疾病的危险因素,包括高血压和体重超重,身体锻炼也可以增加与心血管健康有关的因素,例如心脏机械效率。
      • Physical exercise has been shown to offer protection from dementia and other cognitive problems, perhaps because it increases blood flow or neurotransmitters in the brain, among other potential effects.
        ::身体锻炼证明可以防止痴呆症和其他认知问题,也许因为它增加了大脑的血液流动或神经传导,以及其他潜在影响。
      • Numerous studies suggest that regular aerobic exercise works as well as pharmaceutical antidepressants in treating mild-to-moderate depression, possibly because it increases synthesis of natural euphoriants in the brain.
        ::许多研究表明,定期有氧锻炼和药物抗抑郁剂在治疗中低度低温抑郁症方面起作用,这可能是因为它增加了大脑中自然兴奋剂的合成。
      • Research shows that physical exercise generally improves sleep for most people, and helps sleep disorders, such as insomnia. Other health benefits of physical exercise include better immune system function and reduced risk of type 2 diabetes and obesity.
        ::研究表明,身体锻炼一般会改善大多数人的睡眠,有助于睡眠失调,如失眠,身体锻炼的其他健康好处包括免疫系统功能更好,2型糖尿病和肥胖的风险降低。

      ::锻炼的许多好处可能来自肌肉释放激素,即促进组织修补和生长并产生抗炎效果的肌激素,运动可以减少心血管疾病的危险因素,包括高血压和体重过重;身体锻炼也可以增加与心血管健康有关的因素,例如心脏机械效率;身体锻炼证明可以防止痴呆症和其他认知问题,也许因为它会增加大脑中的血液流动或神经传导器,以及其他潜在影响;许多研究表明,经常的厌食锻炼工作以及治疗轻度至中度抑郁症的药物抗抑郁剂,可能因为它会增加大脑天然兴奋剂的合成;研究表明,身体锻炼通常会改善大多数人的睡眠,有助于睡眠紊乱,例如失眠;身体锻炼的其他健康好处包括更好的免疫系统功能和减少2型糖尿病和肥胖症的风险。
    • There is great variation in individual responses to exercise, partly due to genetic differences in proportions of slow-twitch and fast-twitch muscle fibers. People with more slow-twitch fibers may be able to develop greater endurance from aerobic exercise, whereas people with more fast-twitch fibers may be able to develop greater muscle size and strength from anaerobic exercise.
      ::个人对锻炼的反应差异很大,部分原因是慢动和快动肌肉纤维比例的遗传差异。 较慢动纤维的人也许能从有氧锻炼中产生更大的耐力,而较快动纤维的人则能从厌氧锻炼中产生更大的肌肉体积和体力。
    • Some adverse effects may occur if exercise is extremely intense and the body is not given proper rest between exercise sessions. Many people who overwork their muscles develop delayed onset muscle soreness (DOMS), which may be caused by tiny tears in muscle fibers.
      ::如果锻炼极为紧张,身体在锻炼间隔期间得不到适当的休息,可能会产生一些不利影响。 许多肌肉过度劳累的人会产生迟发性肌肉疼痛(DOMS ) , 这可能是肌肉纤维微小的眼泪造成的。
    • Musculoskeletal disorders are injuries that occur in muscles or associated tissues (such as tendons) because of biomechanical stresses. The disorders may be caused by sudden exertion, over-exertion, repetitive motions, and similar stresses.
      ::肌肉骨骼紊乱是指由于生物机械压力而在肌肉或相关组织(如管)中发生的伤害,这种紊乱可能是由于突然施压、过度施用、重复运动和类似的压力造成的。
      • A muscle strain is an injury in which muscle fibers tear as a result of overstretching. First aid for a muscle strain includes the five steps represented by the acronym PRICE (protection, rest, ice, compression, and elevation). Medications for inflammation and pain (such as NSAIDs) may also be used.
        ::肌肉紧张是指肌肉损伤,肌肉纤维因过度伸展而撕裂;肌肉紧张的急救包括五步(保护、休息、冰、压缩和高压),也可以使用刺激和疼痛的药剂(如国家艾滋病基金)。
      • Tendinitis is inflammation of a tendon that occurs when it is over-extended or worked too hard without rest. Tendinitis may also be treated with PRICE and NSAIDs.
        ::丁丁基炎是当其过度扩展或工作过于艰苦而无休止时发生的一种趋势的炎症,十丁基炎也可以通过PRICE和全国艾滋病基金治疗。
      • Carpal tunnel syndrome is a biomechanical problem that occurs in the wrist when the median nerve becomes compressed between carpal bones. It may occur with repetitive use, a tumor, or trauma to the wrist. It may cause pain, numbness, and eventually — if untreated — muscle wasting in the thumb and first two fingers of the hand.
        ::卡尔帕隧道综合症是手腕中位神经在骨骼之间压缩时出现的一个生物机械问题,可能反复使用、肿瘤或手腕受创伤,可能造成疼痛、麻木,最后——如果未经治疗——肌肉在手拇指和手头两根手指中消瘦。

      ::肌肉紧张是一种损伤,肌肉纤维因过度伸展而撕裂。肌肉紧张的急救包括五步,缩写为PRICE(保护、休息、冰、压缩和高压)的五步,也可以使用刺激和疼痛的药剂(如国家营养指数),丁丁基炎是一种在过度扩展或工作太辛苦而无休止时发生的发炎。丁基炎也可以用PRICE和国家营养指数治疗。 皮肤隧道综合症是一个生物机械问题,在中位神经在骨骼之间压缩时,手腕出现,可能重复使用、肿瘤或手腕受创伤,可能造成疼痛、麻痹,如果未经治疗,最终会造成手拇和手掌头两根的肌肉消瘦。
    • Neuromuscular disorders are systemic disorders that occur because of problems with the nervous control of muscle contractions, or with the muscle cells themselves.
      ::神经肌肉紊乱是系统紊乱,因肌肉收缩的神经控制或肌肉细胞本身的问题而发生。
      • Muscular dystrophy is a genetic disorder caused by defective proteins in muscle cells. It is characterized by progressive skeletal muscle weakness and death of muscle tissues.
        ::肌肉萎缩是肌肉细胞中有缺陷的蛋白质造成的遗传障碍,其特点是骨骼肌肉逐渐衰弱,肌肉组织死亡。
      • Myasthenia gravis is a genetic neuromuscular disorder characterized by fluctuating muscle weakness and fatigue. More muscles are affected, and muscles become increasingly weakened as the disorder progresses. Myasthenia gravis most often occurs because immune system antibodies block acetylcholine receptors on muscle cells, and because of the actual loss of acetylcholine receptors.
        ::脊髓灰质炎是一种遗传性神经肌肉紊乱症,其特征是肌肉弱点和疲劳的波动。 更多的肌肉受到影响,肌肉随着紊乱的进化而变弱。 脊髓灰质炎最常见的原因是免疫系统抗体阻塞肌肉细胞的乙酰胆碱受体,以及乙酰胆碱受体的实际丧失。
      • Parkinson’s disease is a degenerative disorder of the central nervous system that mainly affects the muscular system and movement. It occurs because of the death of neurons in the midbrain. Characteristic signs of the disorder are muscle tremor, muscle rigidity, slowness of movement, and postural instability. Dementia and depression also often characterize advanced stages of the disease.
        ::帕金森病是中枢神经系统的退化性失调症,主要影响肌肉系统和运动。 之所以发生,是因为中脑神经元死亡。 肌肉震颤、肌肉僵硬、行动迟缓和后院不稳定是这种疾病典型的症状。 痴呆和抑郁也经常成为该疾病的晚期特征。

      ::肌肉萎缩是肌肉细胞有缺陷的蛋白质造成的遗传障碍,其特点是骨骼肌肉逐渐衰弱和肌肉组织死亡。 脑膜瘤是一种遗传性神经肌肉肌肉紊乱,其特征是肌肉疲软和疲劳。 肌肉受到更多影响,肌肉越来越弱。 肌肉萎缩最经常发生的原因是免疫系统抗体块状乙酰胆碱受体对肌肉细胞的免疫系统阻力,以及乙酰胆碱受体的实际丧失。 帕金森氏病是中枢神经系统的退化性紊乱,主要影响肌肉系统和运动。它之所以发生,是因为中脑神经死亡。 肌肉衰竭的特征迹象是肌肉干燥、肌肉僵硬性、运动缓慢和后脑不稳定。 痴呆症和抑郁症也经常是疾病晚期的特征。

    As you saw in this chapter, muscles need oxygen to provide enough ATP for most of their activities. In fact, all of the body’s systems require oxygen, and also need to remove waste products, such as carbon dioxide. In the next chapter, you will learn about how the respiratory system obtains and distributes oxygen throughout the body, as well as how it removes  wastes, such as carbon dioxide.  
    ::正如您在本章中所看到的那样,肌肉需要氧气来为其大部分活动提供足够的ATP。 事实上,所有身体系统都需要氧气,还需要清除二氧化碳等废品。 在下一章中,您将了解呼吸系统如何获得并在整个身体中分配氧气,以及它如何清除二氧化碳等废物。

    Chapter Summary Review
    ::" 概述 " 章次

    1. True or False:  Each motor neuron controls one muscle fiber.
    ::1. 真实或假:每个运动神经元控制一个肌肉纤维。

    2. True or False:  Peristalsis is a pattern of muscle contraction in smooth muscle tissue.
    ::2. 真实的或假的:持久性是肌肉在肌肉组织滑动中萎缩的一种模式。

    3. When muscles atrophy...
    ::3. 当肌肉萎缩时...

    a. muscle fibers become narrower
    ::a. 肌肉纤维变窄

    b. muscle fibers turn into fat cells
    ::b. 肌肉纤维变成脂肪细胞

    c. muscle fibers are lost
    ::c. 肌肉纤维丧失

    d. muscle fibers become shorter
    ::d. 肌肉纤维变短

    4. What are tendons?  Name  a muscular system disorder involving tendons.
    ::说明一个肌肉系统紊乱,其中涉及。

    5. Which main type of muscle tissue is used when you make a voluntary movement of one of your limbs?
    ::5. 肢体自愿移动时使用哪类主要肌肉组织?

    6. Which main types of muscle tissue function independently of the brain's conscious control?
    ::6. 何种主要的肌肉组织功能独立于大脑的自觉控制?

    7. Describe the relationship between muscles, muscle fibers, and fascicles.
    ::7. 说明肌肉、肌肉纤维和分册之间的关系。

    8. Is the  autonomic or somatic nervous system responsible for controlling the skeletal
    ::8. 控制骨骼的是由自主或体外神经系统负责的。

    muscles?
    ::肌肉?

    9. True or False:  Sacromeres are the cells of the muscular system.
    ::9. 真实或假:神圣物是肌肉系统的细胞。

    10. True or False:  Muscles contain connective tissue, as well as muscle tissue.
    ::10. 真实或假:肌肉含有连接组织以及肌肉组织。

     

     

    11. The biceps and triceps muscles are shown above. Answer the following questions about these arm muscles.
    ::11. 上文显示了二头肌和三头肌肌肉,回答以下关于这些手臂肌肉的问题。

    a. When the biceps contract and become shorter (as in the picture above), what kind of motion does this produce in the arm?
    ::a. 当二头肌收缩并变短(如上图所示)时,臂部会产生何种运动?

    b. Is the situation described in part (a) more likely to be an isometric or isotonic contraction? Explain your answer.
    ::b. (a) 部分所述情况是否更有可能是同位素收缩或同位素收缩?解释你的答复。

    c. If the triceps were to then contract, which way would the arm move?
    :sadc) 如果三分位采样机当时要订立合同,手臂会以什么方式移动?

    12. Put the following events in order of when they occur during the process of skeletal muscle contraction, from earliest to latest:
    ::12. 将以下事件按在骨骼肌肉收缩过程中发生的时间顺序排列,从最早到最晚:

    a. Acetylcholine binds to receptors on the muscle fiber.
    ::a. 乙酰胆碱与肌肉纤维受体结合。

    b. Actin filaments slide, shortening the sacromere.
    ::b. 细丝滑动滑动,缩短薄膜。

    c. An action potential is initiated in a motor neuron.
    ::c. 在运动神经元中启动行动潜力。

    d. Acetylcholine is released from synaptic vesicles.
    ::d. 乙酰胆碱从神经囊中释放出来。

    13. What are Z discs? What happens to them during muscle contraction?
    ::13. 什么是Z盘?它们在肌肉收缩时会怎样?

    14. True or False:  Synapses only exist between neurons.
    ::14. 真实或假:只有神经元之间存在合成。

    15. True or False:  Muscles can produce hormones.
    ::15. 真实或假:肌肉可产生荷尔蒙。

    16. Relative to the work they do, which muscles have been called the strongest in the human body?
    ::16. 相对于他们所从事的工作,哪些肌肉被称为人体中最强的肌肉?

    a. heart muscles
    ::a. 心脏肌肉

    b. hamstring muscles
    ::b. 刺断肌肉

    c. external eye muscles
    ::c. 外外眼肌肉

    d. stomach muscles
    ::d. 胃肌肉

    17. What is the function of mitochondria in muscle cells? Which type of muscle fiber has more mitochondria ­— slow-twitch or fast-twitch?
    ::17. 肌肉细胞中的米托乔因德里亚的功能是什么?哪种肌肉纤维具有更多的米托乔因德里亚 慢抽动或快抽动?

    18. Fast-twitch and slow-twitch are types of ___________ muscle fibers.
    ::18. 快速开关和慢开关是肌肉纤维的类型。

    a. skeletal
    ::a. 骨骼

    b. smooth
    ::b. 平滑

    c. cardiac
    ::c. 心脏心脏

    d. B and C
    ::d. B和C

    19. Myoglobin __________________________.
    ::19. Myoglobin 。

    a. stores oxygen for anaerobic respiration
    ::a. 储存供厌氧呼吸用的氧气

    b. stores oxygen for aerobic respiration
    ::b. 储存供有氧呼吸的氧气

    c. is present in higher amounts in fast-twitch fibers than slow-twitch fibers
    ::c. 快速抽动纤维的含量高于慢抽动纤维的含量。

    d. is where ATP is produced
    ::d. 生产ATP的所在地

    20. True or False:  All people have the same proportion of slow-twitch to fast-twitch muscle fibers.
    ::20. 真实或假:所有人都有与快速抽动肌肉纤维相同的慢抽动比例。

    21. True or False:  A sprain is a tear in the muscle fibers.
    ::21. 真实或假:扭伤是肌肉纤维的撕裂。

    22. Which condition directly damages neurons, not muscles?
    ::22. 哪个情况直接损害神经元,而不是肌肉?

    a. myasthenia gravis
    ::a. 脊髓灰质炎

    b. muscular dystrophy
    ::b. 肌肉萎缩

    c. musculoskeletal disorder
    ::c. 肌肉骨骼紊乱

    d. parkinson’s disease
    ::d. 帕金森病

    23. What is the difference between primary and secondary Parkinson’s disease?
    ::23. 帕金森病的初级病和二级帕金森病之间有什么区别?

    24. Why can carpal tunnel syndrome cause muscle weakness in the hands?
    ::24. 为什么掌掌中肌肉衰弱会引发掌中骨干隧道综合症?

    25. True or False:  The heart consists of smooth muscle tissue.
    ::25. 真实或假:心脏由光滑的肌肉组织组成。

    26. True or False:  Sprinting is considered an anaerobic exercise.
    ::26. 真实或假:冲刺被视为厌氧练习。