基医专外学Urinary Sytem.pptVIP

* 16. an instrument for examining the inside of the bladder ： cystoscope 17. in front of (pre-) the bladder ： prevesical write a word * 泌尿系统是由过滤血液中过多液体和其他物质的器官组成，其主要功能是维持体液的容积和组成在正常范围内。 * 其功能的一方面是排除细胞代谢堆积产生的废物 * 另一方面是调节体液中各种电解质的浓度和维持血液的PH值。泌尿系统包括肾，输尿管，膀胱和尿道。 * 泌尿系统的主要功能之一是排泄，即排出代谢废物和无用物质的过程 * 泌尿系统通过调控随尿排出的液体量来维持适当的体液容积。 * 另一方面是调节体液中各种电解质的浓度和维持血液的PH值。 * 分泌secrete 肾脏是最重要的排泄器官，其主要功能是维持内环境的稳定为细胞和组织代谢提供最适环境。 * 它们通过从血液分离尿素，矿物盐，毒素和其他废物来完成这项功能。它们同时也保存一定的水盐和电解质。 * 至少一个肾脏必须发挥功能来维持正常的生命活动。 * 调节血浆离子组成。例如钠，钾，钙，镁，氯，碳酸氢盐和磷酸盐等离子就是通过肾脏排泄来调节它们的含量。 * 调节血浆渗透压。 肾脏之所以能调节血浆渗透压是因为它们能直接控制一个人排泄多少的离子和水。 * 调控血浆容积。 肾脏通过控制一个人的排水量来控制血浆容积。 血浆容积对血容量有直接的作用，后者直接影响血压。 NaCl会产生渗透作用，水就会扩散入血。 * 肾脏之所以有这样的功能是因为它们能控制对碳酸氢盐的排泄与持有量。肾脏通过排泄氢离子重吸收碳酸氢根离子来维持血液的PH值 * Purine creatine * 1,25-dihydroxy vitamin D * * calyx * 髓袢 loop of henle limb * 载体 * rugae * 噻嗪类 * FIGURE 3. A nephron and its blood supply. * (2) Reabsorption Within the peritubular capillary network, molecules and ions are reabsorbed back into the blood. Sodium chloride reabsorbed into the system increases the osmolarity of blood in comparison to the glomerular filtrate. * This reabsorption process allows water to pass from the glomerular filtrate back into the circulatory system. * Glucose and various amino acids also are reabsorbed into the circulatory system. These nutrients have carrier molecules that claim the glomerular molecule and release it back into the circulatory system. * If all of the carrier molecules are used up, excess glucose or amino acids are set free into the urine. * (3) Secretion Some substances are removed from blood through the peritubular capillary network into the distal convoluted tubule or collecting duct. These substances are hydrogen ions, creatinine, and drugs. * 2.2 Ureters The ureters are two tubes that drain urine from the kidneys to the bladder. Each ureter is a muscular tube about 25 cm long. Muscles in the walls of the ureters send the urine in small spurts into the bladder. * After the uri