U. Temmy. Rush University.
Appendixes include a variety of supplemen- the results we obtained are integrated into every feature of tary information that students will find useful as they this book 10mg haldol for sale. The text itself has been thoroughly revised and work with the text buy haldol 1.5 mg with mastercard, including answers to the Chapter updated to reflect the latest accepted scientific thought in Checkpoint questions and Zooming In illustration ques- each area of the book purchase haldol 1.5mg overnight delivery. Because visual learning devices are so tions (Appendix 6) that are found in every chapter buy haldol 5 mg free shipping. Last but not least, these designed with the health professions and nursing student features appear in an all-new design that makes the content in mind (the User’s Guide that follows the Preface pro- more user-friendly and accessible than ever. Features marked with an asterisk (*) appear ◗ Organization and Structure in every chapter: ◗ *Learning Outcomes: Chapter objectives on the Like previous editions, the tenth edition uses a body first page of every chapter help the student organize systems approach to the study of the normal human body and prioritize learning. Figure callouts appear in blue type, and table the student’s understanding of concepts depicted in callouts, in red. They are set in a second color to ◗ *Word Anatomy: Organized by chapter headings, this increase their visibility. This learning tool helps students build pronunciations are spelled out in the narrative, vocabulary and promotes recognition of even unfamil- appearing in parentheses directly following many iar terms based on a knowledge of common word parts. The book includes five chically into three NEW levels in this edition kinds of boxes altogether: (answers appear in the Instructor’s Manual): ◗ A Closer Look: Provide additional in-depth scien- ◗ Building Understanding: Includes fill-in-the-blank, tific detail on topics in or related to the chapter. Body in Health and Disease builds on the successes of the ◗ Health Maintenances: Offer supplementary infor- previous nine editions by offering clear, concise narrative mation on health and wellness issues. We have made every effort to respond gram includes full-color anatomic line art, both new thoughtfully and thoroughly to reviewers’ and instruc- and revised, with a level of detail that matches that tors’ comments, offering the ideal level of detail for stu- of the narrative. Also NEW to this edition are pho- dents preparing for a career in the health professions and tomicrographs, radiographs, and other scans, nursing, and the pedagogic features that best support it. User’s Guide In today’s health careers, a thorough understanding of ◗ “A Closer Look” boxes provide additional detail on human anatomy and physiology is more important than selected topics from the text—focusing in on the ever. Memmler’s The Human Body in Health and Disease not details of structure and function. This User’s Guide intro- issues—offering useful information about how to duces you to the features and tools that will enhance your keep the body healthy. We’ve woven that theme into the ◗ “Zooming In” questions ask you to focus in on the book’s design and approach. Take a few minutes to look illustration’s details and answer questions based on through the text and get acquainted with its organization. As with the different body systems, ◗ The “Word Anatomy” chart helps you learn to rec- specific topics build on each other from chapter to chap- ognize new terms based on your knowledge of word ter, with each supporting the ones that follow. We’ve ◗ Chapter summaries provide a quick review of key included some important tools to help you learn about points in outline form—helping you prepare for exams. The pronunciation glossary allows you to ◗ “Hot Topic” boxes provide cutting-edge content on hear the correct pronunciation of key terms from the text trends and research—giving a view to what is hap- and practice them yourself, helping to prepare you to pening in the larger scientific community. The ◗ “Clinical Perspective” boxes focus on physical disor- electronic image atlas, which contains the most important ders and related body processes as well as techniques illustrations from the text, is a convenient study tool that used in clinical settings—providing additional con- lets you review and test your understanding of key body tent on diseases and their treatments. A thorough background in medical termi- organize and manage these records, working closely with nology is essential when reading and interpreting medical physicians, nurses, and other health professionals to ensure records. Others work in medical clinics, Accurate medical records are also essential for administra- government agencies, insurance companies, and consulting tive purposes. Health information technicians assign acodeto firms. Job prospects are promising because of the growing each diagnosis and procedure a patient receives, and this need for healthcare. In fact, health information technology is information is used for accurate patient billing. In addition, projected to be one of the fastest growing careers in the United health information technicians analyze medical records to dis- States. For more information about this profession, contact cover trends in health and disease.
They do not cause any prob- β-Alanine lems for the body order 5 mg haldol with mastercard, in contrast to urate purchase 5mg haldol free shipping, which is produced from the purines and can precipitate purchase haldol 5 mg on line, causing gout cheap 10mg haldol with visa. As with the purine degradation pathway, little energy can H + O be generated by pyrimidine degradation. H C C 3 2 – O CH3 β-Aminoisobutyrate CLINICAL COMMENTS Fig. Water-soluble end products of Hyperuricemia in Lotta Topaigne’s case arose as a consequence of over- pyrimidine degradation. Treatment with allopurinol not only inhibits xan- thine oxidase, lowering the formation of uric acid with an increase in the excretion of hypoxanthine and xanthine, but also decreases the overall synthesis of purine nucleotides. Hypoxanthine and xanthine produced by purine degradation are salvaged (i. PRPP is a substrate for the glutamine phosphoribosyl amidotransferase reaction that initiates purine biosynthesis. Because the normal cellular levels of PRPP and glutamine are below the Km of the enzyme, changes in the level of either substrate can accelerate or reduce the rate of the reaction. Therefore, decreased lev- els of PRPP cause decreased synthesis of purine nucleotides. BIOCHEMICAL COMMENTS A deficiency in adenosine deaminase activity leads to severe combined immunodeficiency disease, or SCID. In the severe form of combined Once nucleotide biosynthesis and immunodeficiency, both T cells (which provide cell-based immunity, see salvage was understood at the Chapter 44) and B-cells (which produce antibodies) are deficient, leaving the indi- pathway level, it was quickly real- vidual without a functional immune system. Children born with this disorder lack a ized that one way to inhibit cell proliferation thymus gland and suffer from many opportunistic infections because of the lack of would be to block purine or pyrimidine syn- a functional immune system. Death results if the child is not placed in a sterile envi- thesis. Administration of polyethylene glycol–modified adenosine deaminase has would interfere with a cell’s ability to gener- been successful in treating the disorder, and the ADA gene was the first to be used ate precursors for DNA synthesis, thereby in gene therapy in treating the disorder. The question that remains, however, is that inhibiting cell growth. This is particularly even though all cells of the body are lacking ADA activity, why are the immune important for cancer cells, which have lost their normal growth regulatory properties. Such drugs have been introduced previously The specific immune disorder is not caused by any defect in purine salvage path- with a number of different patients. Colin ways, as children with Lesch-Nyhan syndrome have a functional immune system, Tuma was treated with 5-fluorouracil, which although there are other major problems in those children. This suggests that per- inhibits thymidylate synthase (dUMP to TMP haps the accumulation of precursors to ADA lead to toxic effects. Arlyn Foma was treated with have been proposed and are outlined below. When deoxyadenosine accumulates, adenosine kinase can convert it to blocking the regeneration of tetrahydrofo- dAMP. Other kinases will allow dATP to then accumulate within the lymphocyte. The other cells of the body are secreting the thymidine synthesis. Mannie Weitzels was deoxyadenosine they cannot use, and it is accumulating in the circulation. As the treated with hydroxyurea to block ribonu- cleotide reductase activity, with the goal of lymphocytes are present in the circulation, they tend to accumulate this compound inhibiting DNA synthesis in the leukemic more so than cells not constantly present within the blood. Development of these drugs would not ribonucleotide reductase becomes inhibited, and the cells can no longer produce have been possible without an understand- deoxyribonucleotides for DNA synthesis. Thus, when cells are supposed to grow ing of the biochemistry of purine and pyrim- and differentiate in response to cytokines, they cannot, and they die. Such drugs also A second hypothesis suggests that the accumulation of deoxyadenosine in lym- affect rapidly dividing normal cells, which phocytes leads to an inhibition of S-adenosylhomocysteine hydrolase, the enzyme brings about a number of the side effects of that converts S-adenosylhomocysteine to homocysteine and adenosine.
The overall transport rate is also determined by such factors as hepatic blood flow discount 10mg haldol with visa, plasma protein binding discount 1.5 mg haldol visa, and the rate of canalicular reabsorption generic haldol 5mg free shipping. The various aspects of the major metabolic processes performed by the liver have been dis- cussed in greater detail elsewhere in this text generic haldol 10 mg without prescription. These sources are referred to as the broad spectrum of the liver’s contributions to overall health and disease are described. She gradually withdrew from much of the 842 CHAPTER 46 / LIVER METABOLISM 843 social support system that her doctors and friends had attempted to build during her Liver lobule efforts for rehabilitation. Upper mid-abdominal pain became almost constant, and To central hepatic vein she noted an increasing girth and distention of her abdomen. Early one morning, she was awakened in excruciating pain in her upper abdomen. She vomited dark-brown “coffee ground” material followed by copious amounts of bright red blood. She Bile called a friend, who rushed her to the hospital emergency room. S canniculus i n Amy Biasis, a 23-year-old missionary, was brought to the hospital emer- u gency room complaining of the abrupt onset of fever, chills, and severe s Hepatocyte o pain in the right upper quadrant of her abdomen. The pain was constant in i nature and radiated to her right shoulder top. She vomited undigested food twice in d the hour before arriving at the emergency room. Her medical history indicated that, while serving as a missionary in western Bile duct Belise, Central America, 2 months earlier, she had a 3-day illness that included fever, Endothelial cells chills, and mild but persistent diarrhea. A friend of Amy’s there, a medical mission- Portal vein Hepatic artery ary, had given her an unidentified medication for 7 days. Amy’s diarrhea slowly resolved, and she felt well again until her current abdominal symptoms began. On physical examination, she appeared toxic and had a temperature of 101 F. Her inferior anterior liver margin was palpable three fingerbreadths below the right rib cage, suggestive of an enlarged liver. Gentle first percussion of the lower posterior right rib cage caused severe pain. Routine laboratory studies were ordered, and a computed tomogram (CT) of the upper abdomen was scheduled to be done immediately. LIVER ANATOMY The human liver consists of two lobes, each containing multiple lobules and sinu- soids. The liver receives 75% of its blood supply from the portal vein, which carries blood returning to the heart from the small intestine, stomach, pancreas and spleen. The remaining 25% of the liver’s blood supply is arterial, carried to the liver by the hepatic artery. Blood from both the portal vein and hepatic artery empty into a common con- duit, mixing their contents as they enter the liver sinusoids (Fig. The sinu- soids are expandable vascular channels that run through the hepatic lobules. They are lined with endothelial cells that have been described as “leaky” because, as blood flows through the sinusoids, the contents of the plasma have relatively free access to the hepatocytes, which are located on the other side of the endothelial cells. The liver is also an exocrine organ, secreting bile into the biliary drainage sys- tem. The hepatocytes secrete bile into the bile canniculus, whose contents flow par- allel to that in the sinusoids but in the opposite direction. The lumina of the bile ducts then fuse, forming the common bile duct.
At the same time discount 5 mg haldol otc, synthesis charide portion of glycoproteins (The synthesis of glycoproteins is discussed in of blood coagulation proteins by the liver Chapter 30 haldol 1.5 mg lowest price. These include mannose discount haldol 1.5 mg otc, fructose generic haldol 1.5 mg fast delivery, galactose, and amino sugars. When the either dietary glucose or hepatic glucose to generate the precursor intermediates for esophageal varices rupture, massive bleed- these pathways. This is because the liver can generate carbohydrates from dietary ing into the thoracic or abdominal cavity as amino acids (which enter gluconeogenesis generally as pyruvate or an intermediate well as the stomach may occur. Much of the of the TCA cycle), lactate (generated from anaerobic glycolysis in other tissues), protein content of the blood entering the and glycerol (generated by the release of free fatty acids from the adipocyte). Of gastrointestinal tract is metabolized by intes- course, if dietary carbohydrate is available, the liver can use that source as well. Because hepa- attached to the protein at its anomeric carbon through a glucosidic link to the –OH tocellular function has been compromised, of a serine or a threonine residue. This is in contrast to the N-linked arrangement in the urea cycle capacity is inadequate, and which there is an N-glycosyl link to the amide nitrogen of an asparagine residue the ammonium ion enters the peripheral cir- (Fig. A particularly important O-linked sugar is N-acetylneuraminic acid culation, thereby contributing to hepatic encephalopathy (brain toxicity due to ele- (NANA or sialic acid), a nine-carbon sugar that is synthesized from fructose- vated ammonia levels). A Partial List of Proteins Synthesized in the Liver Type of Protein Examples Blood coagulation Blood coagulation factors: fibrinogen, prothrombin, Factors V, VII, IX and X. Metal-binding proteins Transferrin (iron), ceruloplasmin (copper), haptoglobin (heme), hemopexin (heme) Lipid transport Apoprotein B-100, apoprotein A-1 Protease inhibitor 1-Antitrypsin 852 SECTION EIGHT / TISSUE METABOLISM A. N-linked O CH2 HOCH2 O C O O O C O HO H H H H NH C CH2 CH O 2 CH NH H OH H O OH H H NH H NH H NH C O C O CH3 CH3 GalNAc Serine GlcNAc Asparagine Fig. The general configuration of O-linked and N-linked glycoproteins. NANA (sialic acid) residues are lost from the serum proteins. This change signals their removal from the circulation and their eventual degradation. An asialoglyco- protein receptor on the liver cell surface binds such proteins, and the receptor–- ligand complex is endocytosed and transported to the lysosomes. The amino acids from the degraded protein are then recycled within the liver. The Pentose Phosphate Pathway The major functions of the pentose phosphate pathway (see Chapter 29) are the gen- eration of NADPH and five-carbon sugars. All cell types, including the red blood cell, can carry out this pathway because they need to generate NADPH so that the activity of glutathione reductase, the enzyme that catalyzes the conversion of oxi- dized glutathione (GSSG) back to reduced glutathione (GSH) can be maintained. Without the activity of this enzyme, the protection against free radical injury is lost. All cells also need this pathway for the generation of ribose, especially those cells that are dividing rapidly or have high rates of protein synthesis. The liver has a much greater demand for NADPH than do most other organs. It uses NADPH for the biosynthesis of fatty acids and cholesterol, which the liver must make to produce phospholipids, and for the synthesis of VLDL and bile salts. It also uses NADPH for other biosynthetic reactions, such as that of proline syn- thesis. NADPH is also used by mixed-function oxidases such as cytochrome P450 that are involved in the metabolism of xenobiotics and of a variety of pharmaceuti- cals. Because the liver participates in so many reactions capable of generating free radicals, the liver uses more glutathione and NADPH to maintain glutathione reduc- tase and catalase activity than any other tissue. Consequently, the concentration of glucose-6-phosphate dehydrogenase (the rate-limiting and regulated enzyme in the pentose phosphate pathway) is high in the liver, and the rate of flux through this pathway may be as high as 30% of the rate of flux through glycolysis. FUELS FOR THE LIVER The reactions used to modify and inactivate dietary toxins and waste metabolites are energy requiring, as are the reactions used by anabolic (biosynthetic) pathways such as gluconeogenesis and fatty acid synthesis. Thus, the liver has a high energy requirement and consumes approximately 20% of the total oxygen used by the body.