By I. Berek. Belmont University.
Niacin 200mg viagra extra dosage amex, also known as nicotinic acid or vita- also lower total cholesterol and triglycerides purchase 150mg viagra extra dosage visa. Low min B, has been shown to reduce LDL levels by 10-20%, 3 glycemic foods include certain fruits, vegetables, beans, and raise HDL levels by 15-35%. Niacin also can cause consist of 20-30 minutes of vigorous aerobic exercise at flushing when taken in high doses. Exercises that cause the heart to levels of isoflavones also have been shown to reduce bad beat faster include fast walking, bicycling, jogging, cholesterol by up to 10%. There of isoflavones in soy protein is recommended, and can be also are a wide selection of aerobic programs available at incorporated into other diet regimens, including vegetari- gyms or on videocassette. In 2003, research revealed that policosanol, a substance made from sugar cane wax or beeswax, lowered LDL cholesterol nearly 27% in study subjects in a Cuban study. A number of clinical studies have indicated that gar- lic can offer modest reductions in cholesterol. A 1997 study by researchers at Pennsylvania State University found men who took garlic capsules for five A wide variety of prescription medicines are avail- months reduced their total cholesterol by 7% and LDL able to treat cholesterol problems. Another study showed that seven cloves of fresh such as Mevacor (lovastatin), Lescol (fluvastatin), Prava- garlic a day significantly reduced LDL, as did a daily chol (pravastatin), Zocor (simvastatin), Baycol (cervas- dose of four garlic extract pills. However, two more re- drugs called fibric acid derivatives are used to lower cent studies have questioned the effectiveness of garlic in triglycerides and raise HDL. A new class of drugs was identified late in 2001 that work differently from the statin drugs. These drugs rely Cholestin hit the over-the-counter market in 1997 as on compounds that bind to a sterol that regulates protein a cholesterol-lowering dietary supplement. It is a (called SCAP) and speds up removal of cholesterol from processed form of red yeast fermented with rice, a tradi- the plasma (the fluid part of the blood. Although the supple- ment contains hundreds of compounds, the major active LDL-lowering ingredient is lovastatin, a chemical also High cholesterol is one of the key risk factors for found in the prescription drug Mevacor. Left untreated, too much bad cholesterol banned Cholestin in early 1998 but a federal district can clog the blood vessels, leading to chest ( court judge lifted the ban a year later, ruling the product ),, and heart attacks. It is not fully un- number one killer of men and women in the United derstood how the substance works and patients may want States. By reducing LDL, people with heart disease may to consult with their physician before taking Cholestin. The Arthritis Cure Better Nutrition Oral Chondroitin Sulfate and Glucosamine Therapy of Arthritis. News Online Unexplained fatigue Persistent low-grade fever Muscle aches and weakness Insomnia or oversleeping Swollen lymph nodes Forgetfulness, confusion Lack of concentration Recurrent sore throat Headaches Joint pain Long-lasting symptoms that continue for six months or longer feverfew pancreatitis amino acids gas digestive enzymes stress tra- ditional Chinese medicine fever rashes conjunctivitis cataracts common cold influenza laryngi- tis headache eczema measles per meal for diabetic patients may help to regulate their food stores: fresh or dried bulk, pill, tincture, and as an blood sugar levels. Other conditions in which cinnamon bark may be helpful include fevers and colds, coughs and, infection and wound healing, some forms of asthma, and • Cinnamon bark may cause an allergic reaction in some blood pressure reduction. More recently, cinnamon bark has been shown to be • Cinnamon bark is not recommended for pregnant or an effective natural snake repellent that is safer to use nursing women. Cinnamon bark is available in several forms from • Essential oil of cinnamon bark is one of the most haz- Chinese pharmacists, Asian grocery stores, and health ardous and should not be used on the Diagnosis Treatment GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 495 Clap Clinical ecology nausea vomiting systemic lupus erythematosus water edemapain diarrhea warts appendicitis cancer traditional Chinese medicine Glycyrrhiza glabra Qing Dai San Yin Huang Kou Fu Yi Yin Qiao Jie Du Pian Huang Lian Shang Qing Wan Melissa officinalis KEY TERMS. Antimicrobial Epstein-Barr In vitro Origins Benefits Side effects Interactions Resources BOOKS OTHER Colonic irrigation Definition Description 514 GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 (Custom Medical Stock Photo. Soluble fibers include medication used to relieve spasms and dilate the pupils pectin, flax, and gums. Fresh fruits and vegetables contain both soluble and insoluble fibers, and • beta blockers (medications used to stabilize irregular since constipation is aggravated by folate, calcium, and heartbeat, lower high blood pressure, reduce chest pain) deficiencies, sources of these nutrients, such as • blood pressure medications asparagus, spinach,, and other dark green leafy vegetables, should be part of the daily diet. Various fruit • calcium channel blockers (medication prescribed to treat juices can also help maintain normal bowel function; sor- high blood pressure, chest pain, some types of irregular bitol, the natural sugar found in apple juice has known laxa- heartbeat and, some non-cardiac diseases) tive properties. For babies, about 1 tablespoon of corn syrup mixed with warm water might help relieve constipation. After nesses) lying down, patients close their eyes and take deep An adult who is constipated may feel bloated, have breaths. For two minutes, the practitioner applies gentle a, swollen abdomen, pass rock-like feces, or fingertip pressure to a point about two inches below the strain, bleed, or feel pain during bowel movements. Everyone becomes constipated once in a while, but Six drops of () and a doctor should be notified if significant changes in six drops of () diluted by one ounce bowel patterns last for more than a week or if symptoms of almond oil, olive oil, or another carrier oil can relieve continue more than three weeks after increasing activity constipation when used to massage the abdomen. Massaging the leg from knee to hip in a primary care physician diagnose constipation. The doc- the morning, at night, and before trying to move the tor uses his fingers to see if there is a hardened mass in bowels is said to relieve constipation. Other diagnostic procedures include a barium enema, which reveals blockage inside the intestine; laboratory analysis of blood and stool samples for internal bleeding A variety of herbal therapies can be useful in the or other symptoms of systemic disease; and a sigmoi- treatment of constipation. Several herbs, including cholesterol zinc diets heart disease nausea vomiting pain diarrhea dizziness headache KEY TERMS. Decoction OTHER Tincture Yang Heart disease Yin Heart attack Corydalis Description Precautions Side effects Interactions Resources BOOKS General use ORGANIZATIONS GALE ENCYCLOPEDIA OF ALTERNATIVE MEDICINE 2 551 While people can generally cough on purpose, a cough is usually a reflex triggered when an irritant stimu- lates one or more of the cough receptors found at differ- ent points in the respiratory system. These receptors then send a message to the cough center in the brain, which in turn tells the body to cough. A cough begins with a deep breath in, at which point the opening between the vocal cords at the upper part of the larynx (glottis) shuts, trap- ping the air in the lungs. As the diaphragm and other muscles involved in breathing press against the lungs, the In addition, gossypol is a chemical found in cottonseed glottis suddenly opens, producing an explosive outflow of oil that is believed to immobilize sperm. In normal situations, most people cough once or twice an hour during the day to clear the airway of irri- tants. However, when the level of irritants in the air is high or when the respiratory system becomes infected, Cotton root bark has not been identified as produc- coughing may become frequent and prolonged.
Only drugs that have a high can be approximately 100 times that found in lipid–water partition coefﬁcient can penetrate the the liver discount 120 mg viagra extra dosage free shipping. Drugs with extremely high lipid–water Drugs that are partially ionized and only moderately partition coefﬁcients have a tendency to accu- lipid soluble will penetrate at considerably slower rates buy viagra extra dosage 130 mg line. However, since blood ﬂow Lipid-insoluble or highly ionized drugs will fail to enter to adipose tissue is low (about 3 mL/100 the brain in signiﬁcant amounts. In addition, because only the unbound form of tion or in prolonged activity when only low a drug is available for diffusion, extensive plasma pro- levels of the drug are needed to produce ther- tein binding also can have dramatic effects on the ex- apeutic effects. Should body fat be seriously re- or encephalitis, may increase the permeability of the duced, as during starvation, stored compounds blood-brain barrier, permitting the passage of ionized 3 Drug Absorption and Distribution 31 lipid-insoluble compounds (e. The ﬂow of cerebrospinal ﬂuid is essentially unidirec- In general, substances that are lipid soluble cross the tional; that is, it ﬂows from its site of formation in the placenta with relative ease in accordance with their choroid plexus through the ventricles to its site of exit at lipid–water partition coefﬁcient and degree of ioniza- the arachnoid villi. Highly polar or ionized drugs do not cross the pla- brain tissue or be returned to the venous circulation in centa readily. However, most drugs used in labor and the bulk ﬂow of cerebrospinal ﬂuid carried through the delivery are not highly ionized and will cross. Some drugs, such as penicillin, will not generally weak bases with pKa values of about 8 and leave the cerebrospinal ﬂuid compartment by bulk ﬂow tend to be more ionized in the fetal bloodstream, since but will be actively transported by the choroid plexus out the pH of fetal blood is around 7. As in the gut, the Pgp transporter sys- Pgp, multidrug resistance–associated protein (MRP), tem is the primary active transporter in the blood-brain and breast cancer resistance protein (BCRP). This ATP-dependent trans- transport proteins are located in many tissues but also porter system picks up substrates that have crossed the appear to be expressed in the placenta. Though the sub- capillary endothelial cells and transports them back to strate speciﬁcities of these proteins have not been com- the systemic circulation, limiting their penetration into pletely described, they appear to function as efﬂux the CNS. Thus, not only are the physicochemical prop- transporters, moving endogenous and exogenous chem- erties of the drug a determinant for penetration into the icals from the placental cells back to the systemic circu- CNS but penetration also depends on whether the drug lation. An important consequence of the existence of a va- riety of routes of drug removal from the brain is that Blood-Testis Barrier drugs that slowly penetrate the CNS may never achieve adequate therapeutic brain concentrations. Penicillin, The existence of a barrier between the blood and testes for example, is a less effective antibiotic centrally than it is indicated by the absence of staining in testicular tissue is peripherally. Morphological studies indicate that the barrier lies beyond the capillary endothelial cells and is most likely to be found at the Placental Barrier specialized Sertoli–Sertoli cell junction. It appears that The blood vessels of the fetus and mother are separated Pgp, the efﬂux transporter protein, also plays a role in by a number of tissue layers that collectively constitute forming this blood-testis barrier. Drugs that traverse this barrier plays a role in preventing certain chemotherapeutic will reach the fetal circulation. The placental barrier, agents from reaching speciﬁc areas of the testis and thus like the blood-brain barrier, does not prevent transport hinders treatment of the neoplasm. Alterations in gastric reduce the amount of foreign chemicals, such as motility may affect the amount of time a drug drugs, that enter the body. One of the more promi- spends in the region of the gastrointestinal tract, nent of these mechanisms is an efﬂux transport sys- where it undergoes the most extensive absorption. Finally, system is: changes in drug formulation can alter absorption by (A) Facilitated diffusion changing dissolution rates. P-glycoprotein transporters in the intestinal lu- (C) Cytochrome P450 3A men serve as an efﬂux transporter for many drugs. All of the following statements concerning the into which they were absorbed and back into the in- blood-brain barrier and the passage of drugs from testinal lumen, reducing absorption. Facilitated dif- the systemic circulation into the cerebrospinal ﬂuid fusion and pinocytosis generally result in drug inﬂux are TRUE EXCEPT: (absorption). The cytochrome P450 3A enzymes (A) Ionized drugs are more likely to cross into the metabolize drugs; therefore, even though they may CSF than un-ionized drugs. Un-ionized drugs cross into the cerebrospinal likelihood that drugs will cross the blood-brain bar- ﬂuid more readily than ionized drugs. Lead can substitute for calcium in the bone crys- (D) P glycoprotein serves to pump drugs back into tal lattice, resulting in bone brittleness. Bone may the systemic circulation from endothelial cells lining become a reservoir for other substances as well. Drugs with extremely high lipid– tial site for drug accumulation of lead that has been water partition coefﬁcients tend to accumulate in fat, ingested? The primary site of absorption is the small intes- Multidrug transporters in prokaryotic and eukary- tine. Because of its large surface area and high otic cells: physiological functions and transport blood perfusion rate, the small intestine is optimal mechanisms. The as the primary cause for the low amounts of orally physician also prescribed diltiazem, a calcium administered cyclosporine reaching the systemic channel blocker used for the treatment of circulation. Since he did not have hypertension, increases the bioavailability of cyclosporine, the patient wondered why this additional drug was reducing the dose of drug needed. Finally, a ANSWER: Cyclosporine is an immunosuppressant drug common adverse effect of cyclosporine therapy is used to prevent transplant rejections. Though an the development of hypertension, and the diltiazem oral formulation is available, it has low somewhat protects the patient from this adverse bioavailability (very little reaches the systemic effect. Tracy Both metabolism and excretion can be viewed as Cytochrome P450 Enzymes processes responsible for elimination of drug (parent The cytochrome P450 (CYP450) enzyme superfamily is and metabolite) from the body. Drug metabolism the primary phase I enzyme system involved in the ox- changes the chemical structure of a drug to produce a idative metabolism of drugs and other chemicals. These drug metabolite, which is frequently but not universally enzymes also are responsible for all or part of the me- less pharmacologically active.
This ﬁnding generic 120mg viagra extra dosage with mastercard, together with an absence of ﬁring away from the resonance peak in mean ﬁring rate tuning curves buy viagra extra dosage 120 mg, led to the observation of tuning of the temporal following properties of trigeminal neurons. Examples of high frequency following and tuning of trigeminal single units are shown in Figure 2. Top Peri-stimulus time histograms (PSTHs) are plotted as a function of frequency of stimulation (ordinate) and time (abscissa). Resonance tuning can be seen in the selective band of increased ﬁring at ~135 Hz: Intrinsic frequency (velocity) sensitivity can be seen in the increased ﬁring above the threshold of ~ 350 Hz. Bottom Neural tuning curves showing mean ﬁring rate for four different epochs post-stimulus onset. Resonance driven activity was not observed in the ﬁrst epoch (0–25 msec post-stimulus onset) although robust high fre- quency responses were present. In later epochs, responses above the intrinsic high frequency threshold diminished in relative prominence while resonance driven neural activity increased. Top panel PSTH of activity evoked at the fundamental resonance frequency (red, 135 Hz) and at a frequency above the intrinsic high frequency threshold (black, 460 Hz). The slower rise time of resonance driven neural activity can be appreciated in this PSTH. Middle panels Traces of vibrissa motion driven by fundamental resonance frequency and high frequency stimuli. The fundamental resonance frequency driven motion shows a gradual increase in motion amplitude (red trace). Bottom panel Plots of the peak velocity of vibrissa motion for the fundamental (red) and high frequency stimuli (black). This time constant for the ampliﬁcation of vibrissa motion is likely a key factor in the delayed increase in resonance driven activity in this example (see also Figure 2. Vibrissae were stimulated with a 500 msec sinusoidal train during extracellular recording of trigeminal ganglion neurons (NV, green) or SI barrel recordings, including fast spiking units (FSU, blue), multi-unit activity (MUA, purple) and regular spiking units (RSU, red). Each bar plot shows the probability of observing a frequency tuned neural response (dark shading), a signiﬁcant evoked increase in mean ﬁring rate without frequency tuning (medium shading), or a neuron not driven by the stimulus (light shading). For all cortical response categories, the incidence of tuned responses and of driven neurons without tuning was increased for epochs >25 msec as compared to the epoch 0–25 msec. Average tuning curves are shown for each neural type for responses centered on the best frequency that drove the largest increase in neural ﬁring (BF), or on the vibrissa fundamental resonance frequency (FRF). The apparent velocity sensitivity of FSU and MUA responses, shown as a sensitivity to higher frequency input, can be seen in the FRF-centered tuning curves for the epochs 100–500 msec post-stimulus onset. Each plot is presented relative to the vibrissa frequency tuning bandwidth26 ( : see Figure 2. Examples are shown of the evolution of vibrissa resonance when stimuli were applied at the fundamental resonance frequency for vibrissae from the 1—4 arcs. Bar plots showing the time constant for the stimulator (black bars), for vibrissa ampli- ﬁcation (gray bars), and for the latency to onset in neural activity (RSU, red bars and FSU, blue bars). The vibrissa time constants and neural latencies shift as a systematic function of the arc of vibrissae stimulated, with longer time constants and neural latencies observed for more posterior vibrissae. These delays provide one cause for the delay in cortical frequency tuning (shown in the above panels and Figure 2. Active neural mechanisms including inhibition and thalamocortical depression likely also play a role. The systematic shift in time constants across vibrissae also generates a map of onset timing within SI that may provide relevant coding information for the behaving animal, and that could increase the efﬁcacy of input to an isofrequency column through enhanced neural synchrony. If temporal cod- ing and not place coding is the relevant mechanism for texture extraction, vibrissa resonance may still play an essential role in the perception of these small amplitude, high frequency stimuli because these inputs would not otherwise be represented by a temporal code, or in any fashion, without this ampliﬁcation. In these examples of ﬁne temporal tuning, only a subset of the amplitudes of stimulation that evoked a mean ﬁring rate increase, also showed high frequency following. The amplitude-dependence of temporal tuning can also be appreciated by examination of the inter-spike interval histograms in Figure 2. While higher amplitudes of stimulation evoked only intervals at the period of the stimulus, lower amplitudes of stimulation evoked intervals that were more likely to be multiples of the frequency period. This difference between the amplitudes necessary for mean ﬁring rate increases and those necessary for temporal following parallels differences observed during auditory stimulation in the cat75 and vibratory stimulation of the monkey skin. They hypothesized that the larger amplitudes of stimu- lation required for primate frequency discrimination might, in contrast, reﬂect the larger amplitude of stimulation necessary to entrain neural ﬁring. Vibrissa Resonance and the Volley Principle As suggested throughout this chapter, several of the questions posed in attempting to understand high frequency encoding in the vibrissa sensory system mirror those traditionally posed in study of the auditory system. The central debate that shaped and continues to inﬂuence the attempt to understand neural mechanisms of auditory perception has been recapitulated here. Speciﬁcally, can high frequency encoding be understood as a place code where the frequency content of a stimulus is determined from a spatial map of frequency established by the biomechanical transduction properties of the peripheral sensors, or, can the ﬁne timing of neural activity, a temporal code, account for pitch perception? Most likely, these mech- anisms work in combination with predominance in different ranges of the percep- tual spectrum. As a solution to this challenge to temporal coding, Wever proposed the volley principle, suggesting that while any given neuron might not follow every cycle of a stimulus, different subpop- ulations within a group of neurons could ﬁre in a phase-locked manner to different © 2005 by Taylor & Francis Group. The top graph shows a frequency tuning curve for a trigeminal unit, constructed by counting all evoked inter-spike intervals (ISIs), a measure that is functionally equivalent to the mean ﬁring rate. The lower graph shows the count of ISIs at the driving period, indicating ﬁne temporal following of the neuron. Numbers adjacent to each curve indicate the amplitude of vibrissa stimulation applied.
Lymphadenopathy This widely distributed protective system has been Lymphadenopathy (lim-fad-en-OP-ah-the) is a term called by several other names order viagra extra dosage 200mg otc, including tissue meaning “disease of the lymph nodes generic 150 mg viagra extra dosage fast delivery. Infectious ◗ Disorders of the Lymphatic mononucleosis (mon-o-nu-kle-O-sis) is an acute viral in- System and Lymphoid Tissue fection, the hallmark of which is a marked enlargement of the cervical lymph nodes. If the lymph nodes are not able to stop the infection, Splenomegaly pathogens may enter the bloodstream, causing sep- ticemia (sep-tih-SE-me-ah), or blood poisoning. Hodgkin dis- ease appears as painless enlargement of a lymph node or thy), especially in the cervical (neck) region, is an early close group of nodes, often in the neck, but also in the sign in many cases. It may spread throughout the lymphatic system than Hodgkin disease and spreads more lymphatic system and eventually to other systems if not readily to other tissues, such as the liver. It appears mostly in older adults and pa- Checkpoint 16-9 What is lymphoma and what are two exam- tients with deficient immune systems, such as those with ples of malignant lymphoma? Chemical and Mechanical Barriers The poliovirus, for example, may be inhaled or swallowed Part of the first line of defense against invaders is the skin, in large numbers and therefore may come into direct con- which serves as a mechanical barrier as long as it remains tact with the mucous membranes lining the respiratory intact. A serious danger to burn victims, for example, is and digestive tracts, yet it causes no apparent disorder of the risk of infection as a result of skin destruction. In contrast, the viruses that cause influenza The mucous membranes that line the passageways and the common cold do attack these mucous mem- leading into the body also act as barriers, trapping foreign branes. Diges- tant avenues of entry include the digestive system and the tive juices destroy many ingested bacteria and their tox- tubes that open into the urinary and reproductive sys- ins. Virulence has two aspects: one may be Checkpoint 17-2 What tissues constitute the first line of de- thought of as “aggressiveness,” or invasive power; the fense against the invasion of pathogens? The virulence of a specific organism also can change; the influenza virus, for example, can be more Phagocytosis is part of the second line of defense against dangerous in some years than in others. In the process of phagocytosis, white blood cells gain virulence as they pass from one infected host to an- take in and destroy waste and foreign material (see Fig. NK cells can recognize body cells with ab- An increase in body temperature above the normal range normal membranes, such as tumor cells and cells infected can be a sign that body defenses are at work. This inflammatory reaction is accompanied by four virus, and it was called interferon because it “interferes” classic symptoms: heat, redness, swelling, and pain, as de- with multiplication and spread of the virus. Each is abbrevi- When tissues are injured, histamine (HIS-tah-mene) ated IFN with a Greek letter, alpha ( ), beta ( ), or and other substances are released from the damaged cells, gamma ( ) to indicate the category of interferon and ad- causing the small blood vessels to dilate (widen). Pure interferons are now available in adequate quan- With the increased blood flow come a vast number of tities for treatment because they are produced by genetic leukocytes. They have been used with varying tered walls and into the tissue, where they can reach the success to boost the immune response in the treatment of irritant directly. Interestingly, in- When this response occurs in a local area, it helps terferon is used to treat the autoimmune disorder mul- prevent the spread of the foreign agent. In a broader sense, the im- 348 ✦ CHAPTER SEVENTEEN mune system will recognize any foreign material and at- Some members of a given group have a more highly tempt to rid the body of it, as occurs in tissue transplan- developed individual immunity to specific diseases. Immunity is a se- example, some people are prone to cold sores (fever blis- lective process; that is, immunity to one disease does not ters) caused by herpes virus, whereas others have never necessarily cause immunity to another. Although cer- If the following description of the immune system tain diseases found in animals may be transmitted to hu- seems complex, bear in mind that from infancy on, your mans, many infections, such as chicken cholera, hog immune system is able to protect you from millions of cholera, distemper, and other animal diseases, do not af- foreign substances, even synthetic substances not found fect human beings. All the while, the system is kept in check, so ences that make human beings immune to these disorders that it does not usually overreact to produce allergies or also make them susceptible to others that do not affect mistakenly attack and damage your own body tissues. Such infections as measles, scarlet fever and diphtheria do not appear to affect animals who come Checkpoint 17-4 What is the difference between inborn and acquired immunity? Antigens Natural Artificial may be found on the surface of patho- genic organisms, on the surface of red blood cells and tissue cells, on pollens, in toxins, and in foods. The critical feature of any substance described as Active Passive Active Passive an antigen is that it stimulates the ac- tivity of certain lymphocytes classified Contact with Placenta Vaccine: Immune as T or B cells. The different types of T cells and some of their leukocyte antigens), because white blood cells are used in functions are as follows: testing tissues for compatibility. The activated Th then produces inter- There are several subtypes of these helper T cells, one leukins (ILs), which stimulate other leukocytes, such as of which is infected and destroyed by the AIDS virus B cells. They are produced by white cells and also by fi- ◗ Regulatory T cells (Treg) suppress the immune re- broblasts (cells in connective tissue that produce fibers) sponse in order to prevent overactivity. B Cells and Antibodies An antibody (Ab), also known as an immunoglobulin (Ig), is a substance pro- The Role of Macrophages Macrophages are phago- duced in response to an antigen. They ingest foreign proteins, such as mature in the fetal liver or in lymphoid tissue before be- disease organisms, and break them down within phago- coming active in the blood. Foreign antigen T cell receptor Helper T cell MHC protein Antigen fragment Activated helper Lysosome Phagocytic vesicle T cell Interleukin 1 Macrophage ingests 2 Macrophage presents 3 Activated T cell foreign antigen antigen fragment with produces interleukin, MHC proteins to which stimulates helper T cell other leukocytes Figure 17-2 Activation of a helper T cell by a macrophage (antigen-presenting cell). The Antigen–Antibody B Reaction memory The antibody that is produced in re- cells sponse to a specific antigen, such as a Plasma bacterial cell or a toxin, has a shape cells that matches some part of that antigen, much in the same way that the shape of a key matches the shape of its lock. Some of the actions of complement are: ulates the cells to multiply rapidly and produce large ◗ It coats foreign cells to help phagocytes recognize and numbers (clones) of plasma cells. BODY DEFENSES, IMMUNITY, AND VACCINES ✦ 351 Box 17-1 A Closer Look Antibodies: A Protein Army That Fights DiseaseAntibodies: A Protein Army That Fights Disease ntibodies are proteins secreted by plasma cells (activated immunoglobulins that vary in molecular size and in function AB cells) in response to specific antigens. Because the plasma contains other globulins as well, bodies, because they are the first to be produced in an immune antibodies have become known as immunoglobulins (Ig). Each time a person is invaded by disease organisms, his or her cells manufacture antibodies that provide im- Artificially Acquired Immunity munity against the infection. Because the host is ac- A person who has not been exposed to repeated small tively involved in the production of antibodies, this type doses of a particular organism has no antibodies against of immunity is called active immunity.
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