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For example order cheap malegra dxt plus line, cervical screening may detect precancer- ous cells which place the individual at risk of cervical cancer purchase malegra dxt plus without a prescription, genetic screening for cystic ﬁbrosis would give the person an estimate of risk of producing children with cystic ﬁbrosis and cholesterol screening could place an individual at high risk of developing coronary heart disease order malegra dxt plus 160 mg with amex. For example, a mammogram may discover breast cancer, genetic testing may discover the gene for Huntington’s disease and blood pressure assessment may discover hypertension. The drive to detect an illness at an asymptomatic stage of its develop- ment (secondary prevention) can be seen throughout both secondary and primary care across the Western world. In Britain, the inter-war years saw the development of the Pioneer Health Centre in Peckham, south London, which provided both a social and health nucleus for the community and enabled the health of the local community to be surveyed and monitored with ease (Williamson and Pearse 1938; Pearse and Crocker 1943). Sweden mounted a large-scale multiphasic screening programme that was completed in 1969 and similar programmes were set up in the former West Germany and Japan in 1970. In London, in 1973, the Medical Centre at King’s Cross organized a computerized automated unit that could screen 15,000 individuals a year. General practice also promoted the use of screening to evaluate what Last (1963) called the ‘iceberg of disease’. In the 1960s and 1970s, primary care developed screening programmes for disorders such as anaemia (Ashworth 1963), diabetes (Redhead 1960), bronchitis (Gregg 1966), cervical cancer (Freeling 1965) and breast cancer (Holleb et al. Recent screening programmes Enthusiasm for screening has continued into recent years. The report (Forrest 1986) concluded that the evidence of the eﬃcacy of screening was suﬃcient to establish a screening programme with three-year intervals. Furthermore, in the late 1980s, Family Practitioner Committees began computer-assisted calls of patients for cervical screening, and in 1993 a report from the Professional Advisory Committee for the British Diabetic Association suggested implementing a national screening programme for non-insulin-dependent diabetes for individuals aged 40–75 years (Patterson 1993). Likewise, practice nurses routinely measure weight and blood pressure to screen for obesity and hypertension. Recent screening programmes have also focused on self-screening in terms of breast and testicu- lar self-examination and over-the-counter tests to measure blood sugar levels, blood pressure and blood cholesterol. In addition, with the development of genetic testing, genetic counselling is now oﬀered for genetic disorders such as cystic ﬁbrosis, Down’s syndrome, Alzheimer’s disease, Huntington’s disease and forms of muscular dystrophy, though many of these programmes are still in the early stages of development. Morris (1964), in his book Uses of Epidemiology, stressed the importance of penetrating to the ‘early minor stages’, then back to the precursors of disease and then back to its pre- dispositions. In 1968, Butterﬁeld, in a Rock Carling Lecture on priorities in medicine, advocated a new emphasis on screening in health-care delivery. Wilson (1965) outlined the following set of screening criteria: s The disease An important problem Recognizable at the latent or early symptomatic stage Natural history must be understood (including development from latent to symptomatic stage) s The screen Suitable test or examination (of reasonable sensitivity and speciﬁcity) Test should be acceptable by the population being screened Screening must be a continuous process s Follow-up Facilities must exist for assessment and treatment Accepted form of eﬀective treatment Agreed policy on whom to treat s Economy Cost must be economically balanced in relation to possible expenditure on medical care as a whole. More recently, the criteria have been developed as follows: s The disease must be suﬃciently prevalent and/or suﬃciently serious to make early detection appropriate. For example, uptake for neonatal screening for phenyl- ketonuria is almost 100 per cent. Marteau (1993) suggested that there are three main factors that inﬂuence uptake of screening: patient factors, health professional factors and organizational factors. Patient factors Several studies have been carried out to examine which factors predict the uptake of screening. These have included demographic factors, beliefs, emotional factors and con- textual factors. Health beliefs: Health beliefs have also been linked to uptake and have been measured using models (see Chapter 2). Emotional factors: Emotional factors such as anxiety, fear, uncertainty and feeling indecent have also been shown to relate to uptake. However, they also argued that although beliefs and emotions predict screening uptake, the nature of these beliefs and emotions is very much dependent upon the screening programme being considered. Some research has also focused on patients need to reduce their uncertainty and to ﬁnd ‘cognitive closure’. For example, Eiser and Cole (2002) used a quantitative method based upon the stages of change model and explored diﬀerences between individuals at diﬀerent stages of attending for a cervical smear in terms of ‘cognitive closure’ and barriers to screening. The results showed that the precontemplators reported most barriers and the least need for closure and to reduce uncertainty. One qualitative study further highlighted the role of emotional factors in the form of feeling indecent. Borrayo and Jenkins (2001) interviewed 34 women of Mexican descent in ﬁve focus groups about their beliefs about breast cancer screening and their decision whether or not to take part. The analyses showed that the women reported a fundamental problem with breast screening as it violates a basic cultural standard. Breast screening requires women to touch their own breasts and to expose their breasts to health professionals. Within the cultural norms of respectable female behaviour for these women, this was seen as ‘indecent’. Contextual factors: Finally contextual factors have also been shown to predict uptake. The results showed that the women often showed complex and sometimes contradictory beliefs about their risk status for the disease which related to factors such as prevalence in the family, family size, attempts to make the numbers ‘add up’ and beliefs about transmission. The results also showed that uptake of the test related not only to the individual’s risk perception but also to contextual factors such as family discussion or a key triggering event. For example, one woman described how she had shouted at the cats for going onto the new stair carpet which had been paid for from her father’s insurance money after he had died from Huntington’s disease. Health professional factors Marteau and Johnston (1990) argued that it is important to assess health professionals’ beliefs and behaviour alongside those of the patients. In a study of general practitioners’ attitudes and screening behaviour, a belief in the eﬀectiveness of screening was associ- ated with an organized approach to screening and time spent on screening (Havelock et al. These rates may well be related to the way in which these tests were oﬀered by the health professional, which in turn may reﬂect the health professional’s own beliefs about the test. Some research has used qualitative methods to further analyse health professional factors. The analyses showed that the interviewees described the consultations in terms of four main themes which were often contradictory. These were providing information that is both objective and full and tailored to the needs of the individual; dealing with emotion by both eliciting it and containing it; communicating both directively and non direc- tively; and performing sophisticated skills whilst having only minimal training. These themes and their contradictions suggest that consultations would vary enormously between patients and between clinicians. For example, whilst a clinician may oﬀer full information for one patient the same clinician might limit the information for another. Similarly, whilst one clinician might tend to be more directive another might be less so. Such variation in health professional beliefs about the consultation and their subsequent behaviour could inﬂuence the patient’s decision about whether or not to have a particular test (see Chapter 4 for more details on communication). This study examines the role of three social psychological models in predicting breast self-examination and cervical screening behaviour. The study illustrates how theories can be empirically tested and how research results can be used to develop interventions to promote screening behaviour. Background It is generally believed that early detection of both breast and cervical cancer may reduce mortality from these illnesses. Therefore, screening programmes aim to help the detection of these diseases at the earliest possible stages.
New York: those who have good vocabularies or above-average read- Oxford University Press order malegra dxt plus 160 mg free shipping, 1964 malegra dxt plus 160mg visa. In order for reliable macist David Ackerman and Bertha (Greenberg) Acker- comparisons to be made discount 160mg malegra dxt plus with mastercard, all standardized tests, including man. They came to the United States in 1912, and were achievement tests, must be given under similar conditions naturalized in 1920. He was married to Gwendolyn Hill and with similar time limitations and scoring procedures. They had two daughters, Jeanne The difficulty of maintaining consistency in these admin- and Deborah. After a short spell (1933–34) as an intern at test form the difference between aptitude—innate abili- the Montefiore Hospital in New York, he interned at the ty—and achievement—learned knowledge or skills—the Menninger Clinic and Sanitorium in Topeka, Kansas. He results of tests that purport to measure achievement joined their psychiatric staff in 1935. Also, some He assumed the post of chief psychiatrist at the children attain knowledge through their experiences, Menninger Child Guidance Clinic in 1937. During frequent topic of discussion among educators, psycholo- this period, he had numerous positions at a variety of in- gists, and the public at large. After the war, Ackerman comes from critics who contend that teachers frequently assumed the post of clinical professor of psychiatry at plan their lessons and teaching techniques to foster suc- Columbia University, and later lectured at the New York cess on such tests. This “teaching to the test” technique School of Social Work, a part of Columbia University. Test In addition to his active career in New York City, anxiety may also create unreliable results. Students who Ackerman served as visiting professor of psychiatry for experience excessive anxiety when taking tests may per- a number of universities, including Tulane University form below their level of achievement. In 1952 Ackerman achievement tests may prove little more than their aver- served as a member of the White House Conference on sion to test-taking. Ackerman published The Unity of the Family and Wallace, Betty, and William Graves. Poisoned Apple: The Bell- Family Diagnosis: An Approach to the Preschool Child in Curve Crisis and How Schools Create Mediocrity and 1938, both of which contributed to the initial promotion Failure. In 1950 Ackerman wrote a book on anti-Semitism in collaboration with Marie Jahoda. Sponsored by the American Jewish Com- mittee, Anti-Semitism and Emotional Disorder, a Psycho- analytic Interpretation examines and analyzes the phe- Nathan Ward Ackerman nomenon and offers possible solutions. He went on to 1908-1971 write many books during his career, including The Psy- Psychologist and educator noted for his work as a chodynamics of Family Life (1958) and Treating the Trou- family therapist, particularly for his ability to look bled Family (1966). He coauthored several books, includ- beyond the traditional assessment of families and to accurately assess the way that family members ing Exploring the Base for Family Therapy and published relate to each other. Ackerman is widely acknowledged as a pioneer in Nathan Ward Ackerman was born in Bessarabia, his field and credited with developing the concept of Russia on November 22, 1908. He believed that the mental or physical disposition of one family member would affect other family mem- A progressive, degenerative disease involving sev- bers, and that often the best way to treat the individual eral major organ systems, including the immune system and central nervous system. He received the Rudolph Meyer award from and conditions, it has been difficult to arrive at a formal the Association for Improvement to Mental Health in definition. Eventually, In 1960, Ackerman opened the Institute for Family similar symptoms were found among intravenous drug Studies and Treatment, a nonprofit organization devoted users, hemophiliacs, and other recipients of blood trans- to promoting family mental health. Ackerman developed a program for research that greatly furthered the effectiveness of the Institute. This journal remains a principal reference for other since 1985 has drastically reduced the risk of transfu- professionals in the field. Children may be infected in utero or is considered perhaps the finest facility for family psy- by exposure to blood and vaginal secretions during chology in the world. The child of an infected mother has a 25 to 35 percent chance of acquiring the virus. Within three to six weeks after infection they may tion of Psychoanalytic Medicine, as well as a member of exhibit flu-like symptoms that last up to three weeks and the Academy of Child Psychiatry, the American Psy- resolve spontaneously. New York: Avon Books, illness is challenging for friends, family, and others 1994. Originally thought of as a “gay men’s dis- as a wave of changing electrical charge. If the test is posi- During an action potential, there is a change in voltage tive, a more specific test, the Western blot assay, is ad- across the nerve cell membrane of about 120 millivolts, ministered. This is followed by progression of the disease, particularly the suppression the movement of potassium ions, which also carry a pos- of the immune system. New York: Mc- nence (especially among young people) and the use of Graw-Hill, 1993. Adaptation is crucial to the trol disorders, such as overeating, constitute a specific process of natural selection. Ethologists, scientists who type of compulsive behavior that provides short-term study the behavior of animals in their natural habitats gratification but is harmful in the long run. In contrast to from an evolutionary perspective, have documented two these various types of potentially addictive behavior, main types of adaptive behavior. Some behaviors, known physical addiction involves dependence on a habit-form- as “closed programs,” transmit from one generation to the ing substance characterized by tolerance and well-de- next relatively unchanged. In spite of the variety of activities that can be con- Adaptation occurs in individual organisms as well as sidered addictive, people who engage in them tend to in species. Sensory adaptation consists of physical have certain attitudes and types of behavior in common. Examples include the adjustment eyes ety or blocking out other types of uncomfortable feel- make when going from broad daylight into a darkened ings. To a greater or lesser extent, people engaged in ad- room and the way bodies adjust to the temperature of dictive behavior tend to plan their lives around it; in ex- cold water after an initial plunge. Once a steady level of treme cases they will do almost anything to obtain the stimulation (such as light, sound, or odor) is established, substance or engage in the behavior. When confronted, dangers called the “fight or flight” syndrome (including they generally deny that they have a problem, although rapid breathing, increased heart rate, and sweating) can privately they regret their addictive behavior, which in also be considered a form of adaptation. The psychologi- many cases they have tried without success to discontin- cal responses involved in classical and operant condi- ue. They tend to rationalize engaging in the behavior and tioning, which involve learned behaviors motivated by tell themselves they can stop whenever they want. They either positive reinforcement or fear of punishment, may also blame others for their addiction and often expe- can also be considered adaptation. Substance abuse and dependence (substance-related Further Reading disorders) are among the psychological disorders in the Bateson, P. Perspectives in Ethology: Behavior and Evolu- list of major clinical syndromes (Axis I) found in the tion. The Beak of the Finch: A Story of Evolution is classified as a depressant, is probably the most fre- in Our Time. Alcohol abuse and dependence affects over 20 million Americans— about 13 percent of the adult population.
Drug-addicted behaviors are postulated to Malinski buy malegra dxt plus 160 mg fast delivery, 1986; Phillips purchase malegra dxt plus cheap online, 1989b; Watson buy generic malegra dxt plus 160 mg online, Barrett, be a painful means to experience an awareness of Hastings-Tolsma, Johnson, & Gueldner, 1997). During the pattern manifestation Rather than repeat the reviews of Rogerian re- knowing and appreciation process, clients are asked search, the following section describes current to name a painful experience, are encouraged to “be methodological trends within the Science of in the moment” in a safe place with the experi- Unitary Human Beings to assist researchers inter- ence/feeling, are asked to identify the choices they ested in Rogerian science in making methodologi- usually make during the painful experience, and are cal decisions. Nursing re- Barrett and Caroselli (1998), Barrett, Cowling, search must be grounded in a theoretical per- Carboni, and Butcher (1997), Cowling (1986), spective unique to nursing in order for the Smith & Reeder (1996), and Rawnsley (1994) have research to contribute to the advance of nursing all advocated for the appropriateness of multiple science. Irreducible human/environmental energy ﬁelds sistent with Rogers’ unitary ontology and participa- are the focus of Rogerian inquiry: Energy ﬁelds tory epistemology. Later, Fawcett (1996) also are postulated to constitute the fundamental questioned the congruency between the ontology unit of the living and nonliving. Both human and epistemology of Rogerian science and the as- beings and the environment are understood as sumptions embedded in quantitative research de- dynamic energy ﬁelds that cannot be reduced to signs; like Carboni (1995) and Butcher (1994), she parts. Pattern manifestations are indicators of change: may be more congruent with Rogers’ ontology and Pattern is the distinguishing characteristic of an epistemology. This chapter presents an inclusive view of Pattern manifestations are the source of infor- methodologies. Nevertheless, the researcher needs mation emerging from the human/environmen- to present an argument as to how the design of the tal mutual ﬁeld process and are the only valid study and interpretations of results are congruent reﬂections of the energy ﬁeld. Further- of concern in Rogerian inquiry is conceptualized more, nurses interested in engaging in Rogerian and understood as manifestations of human/ research are encouraged to use, test, and reﬁne the environmental energy mutual process. Pandimensional awareness: Rogerian inquiry sistent with the ontology and epistemology of the recognizes the pandimensional nature of reality. Human instrument is used for pattern knowing and modification of the Criteria of Rogerian and appreciation: The researchers use themselves Inquiry developed by Butcher (1994) and the as the primary pattern-apprehending instru- Characteristics of Operational Rogerian Inquiry ment. The criteria may be ment sensitive to, and which has the ability to a useful guide in designing research investigations interpret and understand, pandimensional po- guided by the Science of Unitary Human Beings. A priori nursing science: All research ﬂows from a appreciation is the process of apprehending in- theoretical perspective. Every step of the inquiry, formation or manifestations of patterning including the type of questions asked, the con- emerging from the human/environmental ﬁeld ceptualization of phenomena of concern, choice mutual process. The process of pattern knowing of research design, selection of participants, se- and appreciation is the same in the research en- lection of instruments, and interpretation of deavor as described earlier in the Rogerian prac- ﬁndings is guided by the science of unitary tice methodology. It is important to note that because of the aware of dynamic unpredictability and contin- incongruency between ontology and episte- uous change and is open to the idea that pat- mology of Rogerian science with assumptions terns in the inquiry process may change in the in quantitative designs, Carboni (1995b) ar- course of the study that may not have been en- gues that the researcher must select qualitative visioned in advance. It is essential that the researcher docu- ods with Rogerian science and argue that the ment and report any design changes. Pattern synthesis: Rogerian science emphasizes hence, both qualitative and quantitative meth- synthesis rather than analysis. The separation of parts is not consistent ence is reﬂected in the nature of questions with Rogers’ notion of integrality and irre- asked and their theoretical conceptualization ducible wholes. However, qualitative designs, the whole emerging from the human/environ- particularly those that have been derived from mental mutual ﬁeld process. Synthesis allows the postulates and principles of the science for creating and viewing a coherent whole. Shared description and shared understanding: the natural settings where the phenomenon of Mutual process is enhanced by including par- inquiry occurs naturally, because the human ticipants in the process of inquiry where possi- ﬁeld is inseparable and in mutual process with ble. Any “manipulation” of participants in the study enhances shared “variables” is inconsistent with mutual process, awareness, understanding, and knowing par- unpredictability, and irreducibility. The researcher and the researcher-into are inte- are the best judges of the authenticity and va- gral: The principle of integrality implies that lidity of their own experiences, perceptions, the researcher is inseparable and in mutual and expressions. Participatory action designs process with the environment and the partici- and focus groups conceptualized within pants in the study. Each evolves during the re- Rogerian science may be ways to enhance mu- search process. The researcher’s values are also tual exploration, discovery, and knowing par- inseparable from the inquiry. Evolutionary interpretation: The researcher in- and environmental ﬁeld are integral to each terprets all the ﬁndings within the perspective other. Purposive sampling: The researcher uses pur- the ﬁndings are understood and presented posive sampling to select participants who within the context of Rogers’ postulates of en- manifest the phenomenon of interest. Recogni- ergy ﬁelds, pandimensionality, openness, pat- tion of the integrality of all that is tells us that tern, and the principles of integrality, reso- information about the whole is available in in- nancy, and helicy. There is be explored is participatory action and cooperative strong support for the appropriateness of phenom- inquiry (Reason, 1994), because of their congru- enological methods in Rogerian science. Reeder ence with Rogers’ notions of knowing participation (1986) provided a convincing argument demon- in change, continuous mutual process, and inte- strating the congruence between Husserlian phe- grality. Cowling (1998) proposed that a case- nomenology and the Rogerian science of unitary oriented approach is useful in Rogerian research, human beings: because case inquiry allows the researcher to attend to the whole and strives to comprehend his or her [G]iven the congruency between Husserlian phenom- enology and the Rogerian conceptual system, a essence. Husserlian ﬂows from the postulates, principles, and concepts phenomenology as a rigorous science provides just relevant to the conceptual system. Creativity, mystical experiences, tran- the ﬁndings in a way that is consistent with Rogers’ scendence, sleeping-beyond-waking experiences, notions of unpredictability, integrality, and nonlin- time experience, and paranormal experiences as earity. Emerging interpretive evaluation methods, they relate to human health and well-being are also such as Guba and Lincoln’s (1989) Fourth of interest in this science. Feelings and experiences Generation Evaluation, offer an alternative means are a manifestation of human/environmental ﬁeld for testing for differences in the change process patterning and are a manifestation of the whole within and/or between groups more consistent (Rogers, 1970); thus, feelings and experiences rele- with the Science of Unitary Human Beings. Discrete stages of theory development, designs that generate particularistic biophysical phenomena are usually descriptive and explanatory knowledge are relevant not an appropriate focus for inquiry because to the Science of Unitary Human Beings. New concepts with power have been found with anxiety, chronic that describe unitary phenomena may be devel- pain, personal distress, and hopelessness (Caroselli oped through research. For example, the metaphor (Butcher, 2002b), caring (Smith, 1999), and energy “I feel at one with the universe” reﬂects a high de- (Leddy, 2003; Todaro-Franceschi, 1999) are exam- gree of awareness of integrality; “I feel like a worn- ples of concepts that have been reconceptualizied in out shoe” reﬂects a more restricted perception of one’s potential (Johnston, 1994; Watson et al. Future research may focus on developing an Researchers need to ensure that concepts understanding of how human ﬁeld image changes and measurement tools used in the inquiry in a variety of health-related situations or how are deﬁned and conceptualized within a human ﬁeld image changes in mutual process with unitary perspective. Diversity is inherent in the evolution of the a way congruent with Rogers’ principles and postu- human/environmental mutual ﬁeld process. Researchers need to ensure that concepts and evolution of the human energy ﬁeld is character- measurement tools used in the inquiry are deﬁned ized by the creation of more diverse patterns re- and conceptualized within a unitary perspective. Two major concepts— lected patterning modalities designed to foster har- “my motor is running” and “my ﬁeld expansion”— mony and well-being (Hastings-Tolsma, 1992; are rated using a semantic differential technique Watson et al. Examples of indicators of higher veloped within and unitary science perspective that human ﬁeld motion include feeling imaginative, vi- may be used in a wide variety of research studies sionary, transcendent, strong, sharp, bright, and ac- and in combination with other Rogerian measure- tive. Indicators of relative low human ﬁeld motion ments include: include feeling dull, weak, dragging, dark, prag- matic, and passive. The tool has been widely used in • Assessment of Dream Experience Scale, which numerous Rogerian studies. Together, the researcher and Carboni (1992), which is a creative qualitative the participants develop a shared understanding measure designed to capture the changing con- and awareness of the human/environmental ﬁeld ﬁgurations of energy ﬁeld pattern of the healing patterns manifested in diverse multiple conﬁgura- human/environmental ﬁeld relationship. Carboni encouraged to use methods developed speciﬁc to (1995b) also developed special criteria of trustwor- the Science of Unitary Human Beings.
Caffeine is sometimes called guaranine when found in guarana (Paullinia cupana) generic 160 mg malegra dxt plus with mastercard, mateine when found in mate (Ilex paraguariensis) and theine when found in tea cheap malegra dxt plus line. Caffeine is found in a number of other plants buy cheap malegra dxt plus online, where it acts as a natural pesticide. Apart from its presence in the tea and coffee that we drink regularly, caffeine is also an ingredient of a number of soft drinks. Caffeine is also used with ergotamine in the treatment of migraine and cluster headaches as well as to overcome the drowsiness caused by antihistamines. Aconitine is an extremely toxic substance obtained from the plants of the genus Aconitum (family Ranunculaceae), commonly known as ‘aconite’ or ‘monkshood’. Solanine is a poisonous steroidal alkaloid, also known as glycoalkaloid, found in the nightshades family (Solanaceae). Solanine has both fungicidal and pesticidal properties, and it is one of the plant’s natural defences. It has sedative and anticonvulsant properties, and has sometimes been used for the treatment of asthma, as well as for cough and common cold. However, gastrointestinal and neurological disorders result from solanine poisoning. Symptoms include nausea, diarrhoea, vomiting, stomach cramps, burning of the throat, headaches and dizziness. Other adverse reactions, in more severe cases, include hallucinations, loss of sensation, paralysis, fever, jaundice, dilated pupils and hypothermia. The toxicities of samandarin include muscle convulsions, raised blood pressure and hyperventilation. Betaine itself is used to treat high homocysteine levels, and sometimes as a mood enhancer. It causes profound activation of the peripheral parasympathetic nervous system, which may result in convulsions and death. Muscarine mimics the action of the neurotransmitter acetylcholine at the muscarinic acetylcholine receptors. Macrocyclic alkaloids This group of alkaloids possess a macrocycle, and in most cases nitrogen is a part of the ring system. Acanthaceae, Scrophulariaceae, Leguminosae, Ephedraceae and possess various biological properties, for example budmunchiamines L4 and L5, two antimalarial spermine alkaloids isolated from Albizia adinoce- phala (Leguminosae). In this test the alkaloids are mixed with a tiny amount of potassium chlorate and a drop of hydrochloric acid and evaporated to dryness, and the resulting residue is exposed to ammonia vapour. Eating a high carbohydrate diet will ensure maintenance of muscle and liver glyco- gen (storage forms of carbohydrate), improve performance and delay fatigue. Thus, carbohy- drates are a group of polyhydroxy aldehydes, ketones or acids or their derivatives, together with linear and cyclic polyols. Most of these com- pounds are in the form CnH2nOn or Cn(H2O)n, for example glucose, C6H12O6 or C6(H2O)6. Monosaccharides These carbohydrates, commonly referred to as ‘sugars’, contain from three to nine carbon atoms. Most common mono- saccharides in nature possess ﬁve (pentose,C 5H10O5) or six (hexose, C6H12O6) carbon atoms. For example, glucose, a six-carbon-containing sugar, is the most common monosaccharide that is metabolized in our body to provide energy, and fructose is also a hexose found in many fruits. Di-, tri- and tetrasaccharides These carbohydrates are dimers, trimers and tetramers of monosaccharides, and are formed from two, three or four monosaccharide molecules, with the elimination of one, two or three molecules of water. For example, sucrose is a disaccharide composed of two monosaccharides, glucose and fructose. Oligosaccharides The name ‘oligosaccharide’ refers to saccharides con- taining two to 10 monosaccharides. Polysaccharides Polysaccharides are composed of a huge number of monosaccharide units, and the number forming the molecule is often approximately known. For example, cellulose and starch are polysacchar- ides composed of hundreds of glucose units. Classification of monosaccharides according to functional groups and carbon numbers The two most common functional groups found in monosaccharides (in open chain form) are aldehyde and ketone. Sometimes, monosaccharides are classiﬁed more precisely to denote the functional group as well as the number of carbon atoms. For example, glucose can be classiﬁed as an aldohexose, as it contains six carbon atoms as well as an aldehyde group. If any monosaccharide lacks the usual numbers of hydroxyl groups, it is often called a deoxy sugar. For example, 2-amino-2- deoxy-D-glucose, also known as glucosamine, is an amino sugar, and glucuronic acid is a sugar acid. It can be noted that D- and L-notations have no relation to the direction in which a given sugar rotates the plane-polarized light i. In Fischer projections, most natural sugars have the hydroxyl group at the highest numbered chiral carbon pointing to the right. In Fischer projections, L-sugars have the hydroxyl group at the highest numbered chiral carbon pointing to the left. When a sample of either pure anomer is dissolved in water, its optical rotation slowly changes and ultimately reaches a constant value of þ 52. Both anomers, in solution, reach an equilibrium with ﬁxed amounts of a (35 per cent), b (64 per cent) and open chain ($1 per cent) forms. For example, the anomeric carbon (C-1) in glucose is a hemiacetal, and that in fructose is a hemiketal. Only hemi-acetals and hemiketals can exist in equilibrium with an open chain form. Acetals and ketals do not undergo mutarotation or show any of the reactions speciﬁc to the aldehyde or ketone groups. When glucose is treated with methanol containing hydrogen chloride, and prolonged heat is applied, acetals are formed. A sugar solution contains two cyclic anomers and the open chain form in an equilibrium. Once the aldehyde or ketone group of the open chain form is used up in a reaction, the cyclic forms open up to produce more open chain form to maintain the equilibrium. Although only a small amount of the open chain form is present at any given time, that small amount is reduced. Then more is produced by opening of the pyranose form, and that additional amount is reduced, and so on until the entire sample has undergone reaction. Reaction (reduction) with phenylhydrazine (osazone test) The open chain form of the sugar reacts with phenylhydrazine to produce a pheny- losazone. Three moles of phenylhydrazine are used, but only two moles taken up at C-1 and C-2.