1Gastrointestinal Tract (GI tract) Hepatobiliary System
2GI Tract Hepatobiliary GI tract liver Esophagus gall bladder Stomach Small and large intestineHepatobiliarylivergall bladderpancreasThe digestive system is a series of hollow organs joined in a long, twisting tube from themouth to the anus (see figure). Inside this tube is a lining called the mucosa. In themouth, stomach, and small intestine, the mucosa contains tiny glands that produce juicesto help digest food. Two solid organs, the liver and the pancreas, produce digestive juices that reach theintestine through small tubes. In addition, parts of other organ systems (for instance,nerves and blood) play a major role in the digestive system.Why is digestion important?When we eat such things as bread, meat, and vegetables, they are not in a form that thebody can use as nourishment. Our food and drink must be changed into smallermolecules of nutrients before they can be absorbed into the blood and carried to cellsthroughout the body. Digestion is the process by which food and drink are broken downinto their smallest parts so that the body can use them to build and nourish cells and toprovide energy.Functions of the Digestive SystemThe functions of the digestive system are to do the following:1. Ingest the food2. Break it down into small molecules that can cross plasma membranes3. Absorb these nutrient molecules4. Eliminate nondigestible wastesGeneral Anatomy and PhysiologyThe gastrointestinal tract is approximately 30 feet long and extends from the mouth to the anus. It is made up of the oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine. The gastrointestinal tract's function is to transfer nutrients and water from the external environment to the internal environment, where the circulatory system delivers them to cells. The process of digestion begins with chewing. Chewing breaks up food into smaller pieces that can be swallowed without choking. The salivary glands secrete a mucous solution into the mouth that moistens and lubricates food particles. Saliva contains an enzyme that begins to digest carbohydrates. As food particles begin to dissolve, they react with the chemoreceptors in the mouth, giving rise to the sensation of taste.The pharynx and esophagus provide the pathway by which ingested food and drink reach the stomach. Peristalsis (wavelike muscular contraction) moves food down the esophagus into the stomach. Primary peristalsis occurs with swallowing, and usually travels the full length of the esophagus. Secondary peristalsis occurs in response to esophageal distention or irritation caused by gastric reflux, spreading from the point of irritation in the esophagus to the stomach.Once food reaches the stomach, it is stored, dissolved, and partially digested into a solution of hydrochloric acid, enzymes, and food particles that is called chyme. The gastric acid kills most of the bacteria that enter along with the food. Then the stomach pushes the fluid and partially digested food into the duodenum and small intestine to be further digested and absorbed. The large intestine stores the material undigested by the small intestine, and concentrates it by absorbing water.
3Oropharynx Salivary gland Parotid Submanibular gland Sublingual gland MouthThe mouth reveives th efood in its oral cavity. Most people enjoy eating because of the combined sensations of smelling and tasting food. The olfactory receptors, located in the nose, are responsible for smelling, while the taste buds, located on the tongue in elevations called papillae, are responsible for tasting.The roof of the mouth has two parts: an anterior hard palate separates the oral cavity from the nasal passages, and a posterior soft palate separates the oral cavity from the nasopharynx. The hard palate contains several skull bones; namely, portions of the maxillae and palatine bones. The soft palate is merely muscular and ends in the uvula, a cone-shaped process.The tongue is made up of skeletal muscle covered by a mucous membrane. Intrinsic muscles that have their origin outside the tongue, such as on a skull bone. The extrinsic muscles move the tongue about and account for its maneuverability. A fold of mucous membrane on the underside of the tongue attaches the tongue to the floor of the mouth. If the frenulum is too short, the individual cannot speak clearly and is said to be tongue-tied. The floor of the oral cavity and underside of the tongue are richly supplied with blood vessels, and soluble medications will enter the circulation directly if placed beneath the tongue.There are three pairs of salivary glands called the parotid, sublingual, and the submandibular glands. The parotid glands are located in front of and below the ears. Each parotid gland has a duct that opens on the inner surface of the cheek, just at the location of the second upper molar. The sublingual glands lie beneath the tongue proper, and their ducts open into the floor of the oral cavity. The submandibular glands lie in the posterior floor of the oral cavity beneath the base of the tongue. The ducts from the submandibular glands open on either side of the lingual frenulum.The salivary glands produce about one liter of saliva a day, which enters the mouth by way of their ducts. Saliva contains mucus and a digestive enzyme called salivary amylase. Mucus lubricates food so it is easier to swallow, and salivary amylase begins the proces of digesting the food by breaking down starch.The teeth carry out mastication, or chewing of food. The tongue assists in mastication by moving the food between the teeth. Mastication breaks the food up into small portions, making the work of the digestive enzymes more efficient. The tongue forms the chewed food into a small mass called a bolus in preparation for swallowing.How is food digested?Digestion involves the mixing of food, its movement through the digestive tract, and thechemical breakdown of the large molecules of food into smaller molecules. Digestion begins in the mouth, when we chew and swallow, and is completed in the small intestine. The chemical process varies somewhat for different kinds of food.Movement of Food Through the SystemThe large, hollow organs of the digestive system contain muscle that enables their walls to move. The movement of organ walls can propel food and liquid and also can mix the contents within each organ. Typical movement of the esophagus, stomach, and intestine is called peristalsis. The action of peristalsis looks like an ocean wave moving through the muscle. The muscle of the organ produces a narrowing and then propels the narrowed portion slowly down the length of the organ. These waves of narrowing push the food and fluid in front of them through each hollow organ. The first major muscle movement occurs when food or liquid is swallowed. Although we are able to start swallowing by choice, once the swallow begins, it becomes involuntary and proceeds under the control of the nerves.Salivary glands: The glands that act first are in the mouth—the salivary glands. Saliva produced by these glands contains an enzyme that begins to digest the starch from food into smaller molecules.A = NasopharynxB = UvulaC = HypopharynxD = LarynxE = TongueF = Oropharynx
4การเคี้ยว(Chewing or Mastigation) รู้ตัว/ไม่รู้ตัว (หลับตื้น)หน้าที่บดอาหารให้เล็กลง (5-15มล)หล่อลื่นน้ำย่อยแป้ง (amylase)แรงบดเคี้ยว 50-80กก./ฟันกราม!
5การกลืน Swallowing เส้นประสาทรับความรู้สึกในคอหอย (afferent) ศูนย์การกลืนในก้านสมอง medulla & lower ponsเส้นประสาทส่งออก (efferent)เส้นหลัก ไปที่คอหอยและหลอดอาหารส่วนต้นเส้นประสาทสมองคู่ที่ 10 (vagus) ไปที่หลอดอาหารไปที่ศูนย์หายใจPharynxSwallowing, a reflex action which moves food into the esophagus, occurs in the pharynx, a region that opens into the ose, mouth, and larynx. During swallowing, food normally enters only the esophagus, a long, muscular tube that extends to the stomach, because the nasal and laryngeal passages are blocked. The nasopharyngeal openings are covered when the soft palate moves back. The opening to the larynx at the top of the trachea, called the glottis, is covered when the trachea moves up under a flap of tissue, called the epiglottis. Therefore, breathing does not occur when swallowing. This process is easy to observe in the up-and-down movement of the Adam's apple, the ventral cartilage of the larynx, when a person eats.
7หลอดอาหาร (Esophagus) upper esophageal sphincter (UES)กล้ามเนื้อส่วนบนกล้ามเนื้อส่วนล่างเยื่อบุ(mucosa)peristalsis lower esophageal sphincter (LES)The esophagus is the organ into which the swallowed food is pushed. It connects the throat above with the stomach below. At the junction of the esophagus and stomach, there is a ringlike valve closing the passage between the two organs. However, as the food approaches the closed ring, the surrounding muscles relax and allow the food to pass.
8กระเพาะอาหาร (Stomach) reservoirgrindingmixing with digestive fluidcontinuous intestine fillingLower EG sphincterFundusCardiaPylorusBodyThe food then enters the stomach, which has three mechanical tasks to do. First, the stomach must store the swallowed food and liquid. This requires the muscle of the upper part of the stomach to relax and accept large volumes of swallowed material. The second job is to mix up the food, liquid, and digestive juice produced by the stomach. The lower part of the stomach mixes these materials by its muscle action. The third task of the stomach is to empty its contents slowly into the small intestine. Several factors affect emptying of the stomach, including the nature of the food (mainly its fat and protein content) and he degree of muscle action of the emptying stomach and the next organ to receive the contents (the small intestine).AntrumDuodenumnerve control vago-vagus
9Stomach: Reservoir empty vol 50 ml- max vol 4L chyme settle to layers according to densitylarge pieces leave lastlipid... digest lastfluid... bypass
10Stomach: Ginding and mixing Filling the gut Antrum peristalsis RetropulsisFilling the gutcontinuous processing by duodenumprevent duodenal injury by acidprevent bile refluxEmptying time~3 hr
11Stomach: Secretion กรดไฮโดรคลอริก (HCl) 2L/d หลั่งเมือก (mucous) หลั่งน้ำย่อย pepsinogen ย่อยโปรตีนหลั่งปัจจัยในการดูดซึมวิตามินบี 12ฮอร์โมนบางชนิด (gut hormone)ดูดซึมวิตามินบางชนิดStomach:The stomach stores, dissolves, and partially digests the contents of a meal, then delivers this partially digested food to the small intestine in amounts optimal for maximal digestion and absorption. Parietal cells within gastric glands in the folds of the stomach lumen secrete hydrochloric acid (HCl), which makes gastric juice acidic, with a pH less than 2. During a meal, the rate of HCl production increases markedly—seeing, smelling, tasting, and chewing food sends information through the vagus nerves to the parietal cells, causing them to increase acid production. Stomach distention, hydrogen ion concentration, and peptides send messages through long and short neural reflexes to increase gastrin release, which increases HCl production. On average, the stomach produces 2 liters of HCl daily.Microscopic View: Gastric MucosaThe lining of the stomach contains deep collections of cells organized into gastric glands. These gastric glands secrete various substances into the stomach. The openings of the gastric glands into the surface of the stomach are called gastric pits. Mucous cells in the gastric pits secrete mucus. In the deeper part of the gland, parietal cells secrete hydrochloric acid. G cells, which are present predominantly only in the antrum of the stomach, secrete gastrin. ECL cells secrete histamine, and chief cells secrete pepsinogen (an inactive form of the pepsin-digesting enzyme pepsin). Intrinsic factor, needed for the absorption of vitamin B12, is also secreted by the gastric mucosa (most likely the parietal cells).The next set of digestive glands is in the stomach lining. They produce stomach acid and an enzyme that digests protein. One of the unsolved puzzles of the digestive system is why the acid juice of the stomach does not dissolve the tissue of the stomach itself. In most people, the stomach mucosa is able to resist the juice, although food and other tissues of the body cannot.
12ลำไส้เล็ก (Small intestine) duodenum 5% ~25cm.jejunum 40% 1-1.5ileum 55% 2-2.5การย่อยเกิดที่ duodenum และ jejunumหลั่งน้ำย่อยDisaccharidase ย่อย disaccharide เป็น monosaccharideAmino peptidase และ carboxypeptidase's ย่อยเปบไทด์ให้เป็นกรดอะมิโนtwo other digestive organs mix with the food to continue the process of digestion. One of these organs is the pancreas. It produces a juice that contains a wide array of enzymes to breakdown down the carbohydrate, fat, and protein in food. Other enzymes that are active in the process come from glands in the wall of the intestine or even a part of that wall. The liver produces yet another digestive juice—bile. The bile is stored between meals in the gallbladder. At mealtime, it is squeezed out of the gallbladder into the bile ducts to reach the intestine and mix with the fat in our food. The bile acids dissolve the fat into the watery contents of the intestine, much like detergents that dissolve grease from a frying pan. After the fat is dissolved, it is digested by enzymes from the pancreas and the lining of the intestine.he wall of the small intestine is thrown into circular folds with fingerlike projections, called villi. The epithelial cells of each villus have extensions called microvilli. A large number of villi with their microvilli increase the small intestine's surface area for nutrient absorption and give the intestinal wall a soft, velvety appearance.
13Duodenum 25 cm Bunner’s gland: หลั่งด่าง สำหรับน้ำย่อยจากตับอ่อน มีทางเปิดรับน้ำดีจากตับและน้ำย่อยจากตับอ่อนมีน้ำย่อยDisaccharidase ย่อย disaccharide เป็น monosaccharideAminopeptidase ย่อย peptide เป็นกรดอะมิโนDuodenum--The first 25 centimeters contain distinctive glands that secrete mucus and also receive the pancreatic secretions and the bile from the liver through a common duct. Folds and villi are more numerous at the end than at the beginningDUODENUMThe main distinguishing feature of the duodenum is the presence of glands in the submucosa. These duodenal or Brunner's glands produce alkaline secretions to counteract the effects of gastric acids that reach the duodenum. They also provide the necessary alkaline environment for the functioning of the exocrine pancreatic secretions.
14Jejunum 1-1.5 m มีการย่อยและการดูดซึมสารอาหาร ดูดซึมน้ำและเกลือแร่ หลั่ง secretionJejunum--The next meter contains folds and villi, more at the beginning than at the end.JEJUNUMThe main distinguishing feature of the jejunum is the presence of prominent Valves of Kerckring (plicae circulares).
15Ileum 2-2.5 m ดูดซึมสารอาหาร น้ำและเกลือแร่ หลั่ง secreation The last 2 meters contain fewer folds and villi than the jejunum. The ileum wall contains Peyer's patches, aggregates of lymph nodules.ILEUMThe ileum is almost devoid of Valves of Kerckring, however large accumulations of lymphatic tissue, both nodular and dense, are found in the lamina propria. These can often be seen macroscopically as large white patches and are commonly known as Peyer's Patches.
16Large IntestinePartsดูดซึมน้ำและเกลือแร่ที่ลงมาลำไส่ใหญ่ (1L) เหลือ <200 mlสารที่ย่อยไม่ได้จะถูกขับออกมาเป็นอุจจาระtransverse colonAscending colonDescending colonLARGE INTESTINEThe large intestine lacks folds or villi. It is characterized by many tubular intestinal glands with large numbers of goblet cells. This is sometimes described as a glandular epithelium.The large intestine is the site of water absorption (via columnar absorptive cells) and is also the site of formation of the feces. The secretions of the goblet cells provide lubrication for the luminal surfaces. Abundant lymphatic tissue is common in the lamina propria (owing to the large bacterial population in the lumen of the large intestine).Whereas the circular smooth muscle layer is continuous, the longitudinal smooth muscle of the muscularis is in the form of three thick bands, known as teniae coli.The anal region, unlike the rest of the large intestine, has a series of longitudinal folds and the epithelium becomes a stratified squamous epithelium. The large intestine, which includes the cecum, colon, rectum, and anal canal, is larger in diameter than the small intestine. It begins in the lower right quadrant of the peritoneal cavity. The cecum, which lies inferior to this point, has a small projection called the vermiform appendix. Superior to this point, the large intestine is termed the ascending colon. At the level of the liver, the large intestine bends sharply and becomes the transverse colon. At the let abdominal wall, the large intestine bends again to become the descending colon. In the pelvic region, the large intestine turns medially to form an S-shaped bend known as the sigmoid colon. The last 20 centimeters of the large intestine, the rectum, ends in the anal canal, which opens at the anus.The large intestine absorbs water and electolytes. It also prepares and stores nondigestible material (feces) for defecation at the anus. In addition to nondigestible remains, feces also contain bile pigments, which give them color, and large quantities of bacteria, particularly E. coli.The E. coli live off any substances that were not digested earlier. When they break down this material, they emit odorous molecules that cause the characteristic fecal odor. Some of the vitamins, amino acids, and other growth factors produced by these bacteria are absorbed y the intestinal lining. In this way, E. coli and other bacteria perform a service for the human body.sigmoid coloncaecumRectum
17Accessory Organ ต่อมน้ำลาย (Salivary gland) ตับอ่อน (pancreas) ตับ (liver)The salivary glands, the pancreas, liver, and gallbladder are accessory organs of digestion.
18ตับอ่อน (Pancreas) หลั่งน้ำและด่าง หลั่งน้ำย่อย Amylase ย่อยแป้งให้เป็นน้ำตาลโมเลกุลคู่Lipase ย่อยไขมัน ให้เป็น กรดไขมัน + glycerolEsterase ย่อย cholesteryl esterTrypsin + chymotrypsin ย่อยโปรตีนให้เป็นเป็บไทด์ย่อยThe pancreas lies deep in the peritoneal cavity, resting on the posterior abdominal wall. It is an elongated and somewhat flattened organ that has both an endocrine function and an exocrine function. Most of the pancreatic cells produce pancreatic juice, which contains sodium bicarbonate and digestive enzymes for carbohydrates, proteins, and fats. Pancreatic amylase digests starch, trypsin digests protein, and lipase digests fat. In other words, the pancreas secretes enzymes for the digestion of all major types of food. These enzymes travel by way of the pancreatic duct to the duodenum of the small intestine.
19Liver and Biliary system สร้างน้ำดีเก็บไว้ที่ถุงน้ำดีการกระตุ้นการหลั่งน้ำดีมีอาหารเข้าสู่ลำไส้น้ำดีกรดน้ำดีฟอสโฟลิปิดโคเลสเตอรอลLiverThe liver, which is the largest gland in the body, lies mainly in the right upper quadrant of the peritoneal cavity, under the diaphragm. There are two main lobes, the right lobe and the smaller left lobe, which crosses the midline and lies above the stomach. These two lobes are separated by the falciform ligament, which secures the liver to the anterior abdominal wall and the diaphragm. The liver contains about 100,000 lobules that serve as the structural and functional units of the liver.Triads consisting of the following structures are located between the lobules:1) a branch of the hepatic artery, which brings oxygenated blood to the liver,2) a branch of the hepatic portal vein, which brings nutrients from the intestines, and3) a bile duct, which takes bile away from the liver.In some ways, the liver acts as the gatekeeper to the blood. As blood from the intestines passes through the liver, the liver removes poisonous substances and works to keep the contents of the blood constant. It also removes and stores iron and the fat-soluble vitamins A, D, E, and K. The liver makes the plasma proteins from amino acids, and these have important fuctions within the blood itself.The liver maintains the blood glucose level at about 100 mg/100 mL, even though a person eats intermittenly. Any excess glucose in the hepatic portal vein is removed and stored by the liver as glycogen. Between eating periods, glycogen is broken down to glucose, which enters the hepatic portal vein; in this way, the glucose content of the blood remains constant.If, by chance, the supply of glycogen or glucose is depleted, the liver converts amino acids to glucose molecules. In this process, ammonia is given off and is converted to urea, the common nitrogenous waste product of humans. After its formation in the liver, urea is transported to the kidneys for excretion.The liver produces bile. Bile is a yellowish-green fluid because it contains the pigments bilirubin and biliverdin, which result from the breakdown of hemoglobin. Bile also contains bile salts that emulsify fats once bile reaches the duodenum of the small intestine. When fats are emulsified, they break up into droplets that can be acted upon by a digestive enzyme called lipase from the pancreas. Emulsification is a process that can be witnessed by adding oil to water in a test tube. The oil has no tendency to mix with the water, but if a liquid detergent is added and the contents of the tube are shaken, the oil breaks up and disperses into the water.GallbladderThe gallbladder is a pear-shaped, muscular sac attached to the ventral surface of the liver. The liver produces bile, which enters the many bile ducts associated with hepatic lobules. These bile ducts join to form the common bile duct that enters the duodenum. Any excess bile backs up through the cystic duct into the gallbladder where it is stored.Bile, which contains bile salts, bile pigments, cholesterol, and electrolytes, becomes concentrated in the gallbladder as water is reabsorbed. Normally, cholesterol stays in solution, but sometimes it may come out of solution and form crystals. This may happen if the liver secretes too much cholesterol and/or the bile becomes too concentrated in the gallbladder.
20ถุงน้ำดี (Gall Bladder)และน้ำดี (Bile) เก็บน้ำดีที่สร้างจากตับและทำให้น้ำดีเข้มข้นน้ำดีเกลือน้ำดีBile pigment (bilirubin)Cholesterolเกลือแร่หน้าที่ของน้ำดีช่วยในการย่อยไขมันช่วยในการดูดซึมไขมัน วิตามินที่ละลายในไขมัน โคเลสเตอรอลGallbladderThe gallbladder is a pear-shaped, muscular sac attached to the ventral surface of the liver. The liver produces bile, which enters the many bile ducts associated with hepatic lobules. These bile ducts join to form the common bile duct that enters the duodenum. Any excess bile backs up through the cystic duct into the gallbladder where it is stored.Bile, which contains bile salts, bile pigments, cholesterol, and electrolytes, becomes concentrated in the gallbladder as water is reabsorbed. Normally, cholesterol stays in solution, but sometimes it may come out of solution and form crystals. This may happen if the liver secretes too much cholesterol and/or the bile becomes too concentrated in the gallbladder.
21What Does the Liver Do. The liver does >500 jobs What Does the Liver Do? The liver does >500 jobs. Some of the jobs include:StorageStoring energyStore vitamins A, D, E and KDetoxificationKilling germs, helping keep the body healthyKeeping pollutants from hurting the bodyFiltering toxic chemicals from the bodyRemove waste products of nutrient breakdownSynthesisStopping cuts from bleedingBreak down the major nutrients in foods (protein, fats and carbohydrates)Build proteinsHelping build musclesMake and secrete bile to help digest foodsIn some ways, the liver acts as the gatekeeper to the blood. As blood from the intestines passes through the liver, the liver removes poisonous substances and works to keep the contents of the blood constant. It also removes and stores iron and the fat-soluble vitamins A, D, E, and K. The liver makes the plasma proteins from amino acids, and these have important fuctions within the blood itself.The liver maintains the blood glucose level at about 100 mg/100 mL, even though a person eats intermittenly. Any excess glucose in the hepatic portal vein is removed and stored by the liver as glycogen. Between eating periods, glycogen is broken down to glucose, which enters the hepatic portal vein; in this way, the glucose content of the blood remains constant.If, by chance, the supply of glycogen or glucose is depleted, the liver converts amino acids to glucose molecules. In this process, ammonia is given off and is converted to urea, the common nitrogenous waste product of humans. After its formation in the liver, urea is transported to the kidneys for excretion.The liver produces bile. Bile is a yellowish-green fluid because it contains the pigments bilirubin and biliverdin, which result from the breakdown of hemoglobin. Bile also contains bile salts that emulsify fats once bile reaches the duodenum of the small intestine. When fats are emulsified, they break up into droplets that can be acted upon by a digestive enzyme called lipase from the pancreas. Emulsification is a process that can be witnessed by adding oil to water in a test tube. The oil has no tendency to mix with the water, but if a liquid detergent is added and the contents of the tube are shaken, the oil breaks up and disperses into the water.
22Nutrient Digestion and Absorption FatCarbohydrateProteinVitaminminerals
24Protein Absorption เริ่มถูกย่อยที่กระเพาะอาหาร โดย pepsin ย่อยอย่างสมบูรณ์เป็นกรดอะมิ โนที่ลำไส้เล็กด้วยน้ำย่อยจาก ตับอ่อนและจากลำไส้เล็กดูดซึมในรูปของกรดอะมิโน60-90 g/dProtein. Foods such as meat, eggs, and beans consist of giant molecules of protein thatmust be digested by enzymes before they can be used to build and repair body tissues.An enzyme in the juice of the stomach starts the digestion of swallowed protein. Furtherdigestion of the protein is completed in the small intestine. Here, several enzymes fromthe pancreatic juice and the lining of the intestine carry out the breakdown of hugeprotein molecules into small molecules called amino acids. These small molecules canbe absorbed from the hollow of the small intestine into the blood and then be carried toall parts of the body to build the walls and other parts of cells.
25Biliary Transport and Storage Fat DigestionLiverDuodenumBiliary Transport and StorageJejunumAs shown by the white box, fat digestion occurs in the lumen of the small intestine and is facilitated by these micellar particles.IleumColon
26Fatty Acids + Monoglycerides Fat DigestionDietary CholesterolTriglyceridesFatty Acids + MonoglyceridesFat in the diet consists of cholesterol as well as triglycerides. Dietary cholesterol is incorporated into micelles together with the biliary cholesterol that was already present. Dietary triglycerides are partially broken down by pancreatic lipases into fatty acids and monoglycerides, which are also incorporated into micellar particles.
27Biliary Transport and Storage Fat AbsorptionLiverDuodenumBiliary Transport and StorageJejunumAs shown by the white box, fat absorption occurs at the wall of the small intestine.Lymphatic SystemIleumColon
28Vitamin Absorption Water soluble vitamin Fat soluble vitamin B12 ดูดซึมเช่นเดียวกับกรดอะมิโนและน้ำตาลโดย active transport และ passive diffusion, ที่ Jejunum และ IleumFat soluble vitaminดูดซึมไปพร้อมไขมันB12ต้องอาศัย กรดในกระเพาะอาหาร intrincic factor ในกระเพาะอาหารน้ำย่อยตับอ่อนดูดซึมที่ terminal ileum
29เกลือแร่ Mineral Site Regulatory factors Iron Duodenum and proximal small intestineRelative absorption: Haem>Fe2+>Fe3+CalciumParathyroid hormonePhosphateProximal small intestine1,25 vit DMagnesiumJejunum and IleumCopper ZincComplex interaction
30น้ำและเกลือแร่ น้ำ~9L/d Reabsorption > 90% reabsorbed, only litres are discarded in the faecesUpper small intestine:4 to 5 litres reabsorbedIleum:active transport of NaCl3 to 4 litres reabsorbedColon:active transport of NaCl in exchange for K+ and HCO3-normally ml absorbed (up to 7 litres)regulated by mineracorticoidsSourceLitresDietary intake2Saliva1Gastric juicePanreatic secretionBileSmall intestinal secretion (esp. duodenum)Total9Water and electrolytes9 litres enter the GI tract each day:SourceLitresDietary intake2Saliva1Gastric juice2Panreatic secretion2Bile1Small intestinal secretion (esp. duodenum)1Total9Reabsorption > 90% reabsorbed, only litres are discarded in the faecesUpper small intestine:highly permeable to H2O and NaCl4 to 5 litres reabsorbedhyperosmolar until sugars and amino acids are absorbed, then isomolarIleum:active transport of NaCllower permeability to passive diffusion3 to 4 litres reabsorbedColon:active transport of NaCl in exchange for K+ and HCO3-normally ml absorbed (up to 7 litres)ion absorption is regulated by mineracorticoids
31ใยอาหาร (Dietary Fiber) เป็นกลุ่ม CHO ที่ไม่ถูกย่อยโดยทางเดินอาหารแบ่งเป็นละลายน้ำไม่ละลายน้ำพบมากใน all-natural cereals, whole-grain, beans, fruits, vegetables, nuts.จำเป็นต่อการทำงานของทางเดินอาหารควรได้รับ g/dควรค่อยๆเริ่ม และกินให้หลากหลายช่วยลดท้องผูก ริดสีดวง ควบคุมน้ำหนัก ป้องกันโรคเรื้อรังบางชนิดWhat Is Fiber?Fiber is a virtually indigestible substance that is found mainly in the outer layers of plants. Fiber is a special type of carbohydrate that passes through the human digestive system virtually unchanged, without being broken down into nutrients. Carbohydrates constitute the main source of energy for all body functions.Almost everyone hears about the need for enough fiber in the diet. But few people understand the importance of dietary fiber - or where to get it.Fiber is important because it has an influence on the digestion process from start to finish:Because it demands that food be more thoroughly chewed, fiber slows down the eating process and helps contribute to a feeling of being full, which in turn can help prevent obesity from overeating.Fiber makes food more satisfying, probably because the contents of the stomach are bulkier and stay there longer.Fiber slows digestion and absorption so that glucose (sugar) in food enters the bloodstream more slowly, which keeps blood sugar on a more even level.Fiber is broken down in the colon (the main part of the large intestine) by bacteria (a process called fermentation), and the simple organic acids produced by this breakdown helps to nourish the lining of the colon.These acids also provide fuel for the rest of the body, especially the liver, and may have an important role in metabolism.Substantial amounts of fiber can be found in foods such as:All-natural cerealsWhole-grain breadsBeansFruitsVegetablesNutsThere are two main types of fiber, and they have different effects on the body:Insoluble fiber is mainly made up of plant cell walls, and it cannot be dissolved in water. It has a good laxative action.Soluble fiber is made up of polysaccharides (carbohydrates that contain three or more molecules of simple carbohydrates), and it does dissolve in water. It has a beneficial effect on body chemistry, such as lowering blood cholesterol and blood sugar levels.
34บทบาทของใยอาหารต่อทางเดินอาหาร ปากเคี้ยวได้ช้า ใช้พลังงาน ขัดฟันกระเพาะอาหารอิ่มเร็ว อาหารค้างในกระเพาะนานขึ้นลำไส้เล็กอิ่มเร็ว ลดและชะลอการดูดซึมไขมัน น้ำตาลโคเลสเตอรอล เหล็ก แคลเซียมลำไส้ใหญ่ส่วนต้นเป็นอาหารของแบคทีเรีย สร้างกรดไขมันสั้น เป็นอาหารของเซลล์ลำไส้ เพิ่มเนื้ออุจจาระ ดูดซึมน้ำและเกลือ ลดการดูดซึมสารพิษลำไส้ใหญ่ส่วนปลายขับอุจจาระเร็วขึ้น อุจจาระนุ่มไส้ตรงและก้นอุจจาระนุ่ม ขับอุจจาระได้ง่ายFiber is attacked and broken down by the huge population of bacteria that live in the colon.The breakdown products are acids and gases. This process is called fermentation. Dietary fiber is only partly fermented, because some plant cell walls resist bacterial attack.The simple organic acids produced by fermentation are mostly absorbed, and in doing so they nourish the lining of the colon. They also provide fuel for the rest of the body, especially the liver. This may have important consequences for metabolism; half the calories in fiber are made available to the body.The gases arising from fermentation soften and enlarge the stool. They are also passed as wind (flatus) and can contribute to bloated feelings in some people.
36Choking Conscious Prevent is no accident Unconscious If cough, breath, speak, do not interfereIf not, Heimlich maneuver until FB is expelled or victim unconsciousPrevent is no accidentsmall pieces, chew slowly, avoid laughing, talking, heavy alcoholUnconscious
37Gastro esophageal Reflux Disease: GERD Symptoms of GERD include:HeartburnWater brash (reflex salivary hypersecretion in response to peptic esophagitis),LaryngitisAspiration (passage of gastric fluid up the esophagus and down into the lungs)Wheezing Night time awakening with choking
61Cirrhosisเป็นระยะท้ายของโรคตับที่มีพังผืดในตับ ทำให้มีการเปลี่ยนแปลงโครงสร้างอย่างถาวรของตับและทำให้การทำงานของตับเสียไปCirrhosis represents a late stage of progressive hepatic fibrosis characterized by distortion of the hepatic architecture and the formation of regenerative nodules. It is generally considered to be irreversible in its advanced stages at which point the only option may be liver transplantation. Patients with cirrhosis are susceptible to a variety of complications and their life expectancy is markedly reduced