Starting with A for "ACE inhibitor" and continuing through to Y for "Yolk Sac Tumour", we give you succinct explanations for scientific and medical terms in clear and simple words.
- SaccharinSaccharin is one of the artificially produced sweeteners, which is about 300 times as sweet as cane sugar (saccharose). Sodium saccharin is used as a sugar substitute for diabetics and is excreted unchanged in the urine. It is possible that it causes cancer.
- Saccharosealso known as sucrose
Saccharose is a disaccharide which is composed of glucose and fructose. It occurs in sap as a transport form of soluble carbohydrates. Saccharose is split by enzymes (disaccharidases) in the organism into glucose and fructose.
- SarcomaMalignant tumour of supportive or connective tissue, striated muscles, almost all smooth muscles cells, heart muscles, the cells which coat blood vessels and of blood cells. Sarcomas form metastases in other organs along the bloodstream at an early stage in the disease, mostly before diagnosis.
- ScintigraphyNuclear medical imaging procedure for recording the spatial distribution of radioactive substances in the body or organs, if required at different times. After uptake of the radioactive substance, it is either enriched relatively selectively in the organs or tissues to be examined, or is not stored. With the help of special detectors and computer-based analysis the spatial distribution of the radiation emitted from the body can be registered as a two- or (more rarely) three-dimensional scintigram.
1. Static scintigraphy: static single image or image of the whole body, particularly for the localisation of so-called frozen functional or metabolic states without altering the time of the image (e.g. thyroid or skeleton scintigram). 2. Sequence or dynamic scintigraphy: Series of scintigrams to record changes in activity within a functionally specific time, with the possibility of setting up functional curves.
- SclerosisPathological hardening of tissues, organ parts or organs. Cf. arteriosclerosis, coronary sclerosis, osteosclerosis.
- Sclerosis of the aortaArteriosclerosis of the aorta. In ca. 15 % of cases this is in the curve of the aorta and in about 85 % of cases in the abdominal aorta.
- Screening testalso know as pretest, search test or sieve test
Sieve test which saves both time and money, for instance for the first identification of dangerous substances or characteristics. A particular use of such a test is for the early recognition and registration of a stage of a disease which is as yet free of symptoms. Examples of the use of such tests include studies of series of patients for type 2 diabetes and the screening of new-born babies for the early diagnosis of diseases which are readily treated but which have a severe course (e.g. hip dysplasia and metabolic anomalies).
- Seasonal affective disorderDepressive disease which occurs regularly, mostly between autumn and spring. Seasonal affective disorder by loss of energy, excessive sleep requirement and increase in weight (cf. overweight).
Antidepressives, also light therapy.
- secondary hyperparathyroidisma disorder characterised by overactivity of the parathyroid glands with excessive secretion of parathyroid hormone; it results from altered calcium, phosphorus and vitamin D metabolism in chronic kidney disease
- seizureabnormal electrical discharge of brain tissue, often resulting in uncontrolled body movements or behaviour
- Sepsisalso known as septicaemia or blood poisoning
General infection with symptoms of illness, in which microorganisms (mostly bacteria, more rarely fungi, viruses or parasites) reach the circulation from a so-called focus. Possible focuses of infection include the navel (for new born babies), often the urogenital tract (e.g. infections of the urinary tract or infections after birth), the skin (e.g. infections from wounds), ENT (e.g. inflammation of the tonsils, of the frontal sinuses or of the middle ear), the lungs (e.g. pneumonia) or the intestine (e.g. inflammation of the diaphragm).
Include treatment which suppresses the immune response, preceding operation, implant or indwelling catheter (e.g. in bladder or vein), diabetes mellitus.
Typically, high fever, chills, clearly impaired general feeling of wellbeing, which may extend to confusion, often grey-pale skin, later (soft) spleen and liver enlargement and infectious and toxic damage to internal organs (kidneys, lungs, heart). Pathogens established in the body can cause inflammation of the cerebral membrane (meningitis), brain abscess, lung abscess, arthritis or inflammation of the bone marrow.
Immediate treatment with antibiotics.
In spite of intensive medical care, the prognosis is serious (mortality ca. 50%), and is particularly unfavourable if the treatment starts late, if the focus of infection cannot be localised, in cancer patients, or if there is multiorgan failure in the course of the treatment.
- Septicaemiasee sepsis
- serinean amino acid (C3H7NO2S) that occurs especially as a structural part of many proteins and is a precursor in the synthesis of the amino acid glycine; can be synthesised in the body
- SerogroupA closely related group of microorganisms, identified with a specific antiserum, which reacts with common structural elements in the antigens of the serogroup.
- SerotypeMicroorganisms which belong to a serogroupand which are identifiable by a certain pattern of antigens with the help of a specific antiserum.
- serum creatinineconcentration of creatinine in blood serum
- sialic acida negatively charged sugar molecule found in human erythropoietin
- sickle cell diseasean inherited disorder that occurs primarily in people of African descent and causes defects in the structure of hemoglobin, resulting in abnormal structure and function of red blood cells
- sideroblastic anemiasa group of anemias that are all characterised by the accumulation of iron deposits in immature red blood cells; these cells do not mature normally and many are destroyed in the bone marrow before reaching the circulation
- SinusitisParanasal sinus inflammation
Acute or chronic inflammation of one or several paranasal sinuses (maxillary sinus, frontal sinus, sphenoid sinus, ethmoid cells). In adults the maxillary sinuses are most often affected.
Infections transmitted from the nasal cavity, particularly viruses (e.g. the influenza virus) or bacteria (e.g. Haemophilus influenzae, streptococci, staphylococci).
General feeling of being washed out, pain in the face and head, problems with breathing through the nose. Chronic sinusitis often exhibits few symptoms.
Nose drops to reduce swelling, camomile steam bath, warmth, possibly antibiotics, rinsing of the paranasal sinuses, possibly operation.
Very rare rupture into the external soft tissue, into the eyes or cranial cavity, causing for example meningitis.
- Sitosterolsee lipid sinkers
- Sleep apnoea syndromeDisturbance in breathing during sleep, with occasional interruption to respiration. Sleep apnoea syndrome leads to remove oxygen deficiency (hypoxaemia) and excess of carbon dioxide (hypercapnia) in the blood. This is accompanied by waking reactions from the central nervous system and periodic fluctuations in blood pressure, sleeping cardiac output and heart rate, waking high blood pressure (hypertension) and increased risk of stroke or myocardial infarct.
Abnormal tiredness during the day, irregular and loud snoring, disturbances in concentration and memory, changes in personality, morning headache, disturbance in potency.
For mild forms of the syndrome, drugs to expand the bronchi. Possibly operative correction of a restriction of the respiratory tract or continuous hyperbaric ventilation. Possibly long term treatment with oxygen.
- Small intestineThe small intestine is 4-5 m long and is subdivided into the duodenum, jejunum and ileum. The ileum lies in the right upper abdomen at the exit from the stomach and receives the efferent ducts from the pancreas and the gall bladder (see bile acids) The whole mucous membrane of the small intestine has a large number of protrusions (folds and villi), which increase the absorption area for the uptake of nutrients from chyme. The final section of the small intestine, the ileum, opens into the large intestine. Cf. digestion.
- Small vessel diseaseName for the disease of the small branches of the coronary arteries (microangiopathy) inside heart tissue which leads to coronary insufficiency. The larger coronary vessels, which lie on the heart, are not constricted. A frequent cause of this condition is diabetes mellitus (type 2 diabetes mellitus, type 1 diabetes). Cf. coronary heart disease.
- Sodium fluorideNaF; chemical substance; uses include the prevention of caries or in osteoporosis.
- Soft Tissue SarcomaA malignant soft tissue tumour which can exhibit very great biological and tissue variability and which spreads metastases through the blood vessels at a very early stage.
Localisation: 50% in the arms and legs.
Symptoms: Often no symptoms, pain from pressure on the nerves.
Diagnosis: Computer tomography, nuclear spin tomography, X-ray investigation of the blood vessels, taking of tissue samples by surgery (biopsy)
Therapy: Surgical removal, also tumour irradiation before or during the operation also chemotherapy, which may be restricted to the site of growth of the tumour.
Prognosis: With regular aftercare, the 5-year survival rate is 70-75%, with local relapses 35-50%, with distant metastases less than 5%.
- Soft Tissue TumoursAll tumours which originate in tissues which is not part of the skeleton or epithelium
A distinction is made between benign soft tissue tumours (such as fibromas, leiomyomas, rhabdomyomas, neurofibromas, mesenchyomas) and malignant soft tissue tumours (see soft tissue sarcoma).
- Softening of the bonessee osteomalacia, rickets
- SomatostatinAbbreviated as SIH, "somatotropin release inhibiting hormone"
Hormone which has been detected in one part of the midbrain (hypothalamus) and in the D-cells of the islets of Langerhans. It inhibits the release of other hormones, including growth hormone, STH, ACTH, insulin and glucagon.
- Somogyi effectPhenomenon named after the American biochemist Michael Somogyi (1883-1971). This describes how an excessively high dose of the hormone insulin leads first to low blood sugar concentrations (hypoglycaemia), followed by reactive development of excessively high blood sugar concentrations (hyperglycaemia). Occurs in patients with badly controlled diabetes mellitus (mostly type 1). If the evening dose of insulin is too high, this causes hypoglycaemia during the night (ca. 3-4 hours) and hyperglycaemia in the morning. Cf. diabetic counterregulation.
- SonographySee Ultrasound
- Sorbitolalso known as sorbit
Hexavalent sugar alcohol which is formed in the organism as an intermediate product in the conversion of fructose to glucose. Sorbitol can be made technically. One of its uses is as starting material for the production of ascorbic acid (vitamin C). In the liver fructose can be enzymatically converted into fructose and in this way can enter fructose metabolism, which is independent of insulin. Sorbitol can be used to alter taste. It is suitable for diabetics as a sugar substitute (see sweeteners). At high doses, sorbitol acts as a laxative. Cf. type 2 diabetes.
- SpleenThe spleen lies in the left upper abdomen near the diaphragm. A healthy spleen cannot be felt through the abdominal wall. The spleen is connected to the blood circulation and is part of the lymphatic system. Aged or damaged blood cells, microorganisms and other products of the immune system are broken down by macrophages in the spleen. The spleen also participates in the development of the specific properties of the B- and T-cells.
- Spontaneous deformationAcute or insidious deformation of the vertebral bodies and the arm or leg bones, as a result of structural changes without force having been applied.
Metabolic disturbances as a result of poor nutrition or changes in hormone levels from glandular dysfunction (e.g. osteoporosis, rickets, osteodystrophia deformans), cancer metastases (e.g. prostatic cancer, plasma cytoma) or drug action (e.g. after long-term treatment with glucocorticoids).
Cf. osteomalacia, fracture, pathological.
Starch is a very long chain polysaccharide derived from glucose, which consists to 20% of water soluble amylose (unbranched glucose chains) and to 80 % of water insoluble amylopectin (branched glucose chains). Starch is only produced by plants, where it is the most important carbohydrate reserve, together with inulin. The organs in the plant which store starch include the tuber, seeds and roots. Starch covers most animal requirements for carbohydrates. The breakdown of starch in the organism is carried out by enzymes, which are known as amylases. Cf. digestion of carbohydrates.
- Stenocardiasee angina pectoris
- StenosisIn-born or acquired constriction of hollow organs or vessels.
- Stentsee PTCA
- Steroid diabetesDevelopment of glucose in the urine (glucosuria) or diabetes mellitus during therapeutic treatment with glucocorticoids (steroid hormones). Liver disease encourages this development.
- Steroid hormonesSteroids are organic compounds with 18-30 carbon atoms which function as hormones. Human steroid hormones include sex hormones, adrenal hormones (glucocorticoids, mineral corticoids) and calciferols.
- Steroid osteoporosisOsteoporosis after high dose and long-term treatment with glucocorticoids, with severe changes in the skeleton, particularly in the backbone, ribs, thigh bones, pelvis and skull. Steroid osteoporosis is the most frequent of the so-called secondary forms of osteoporosis.
- STHAbbreviation for somatotropic hormone, also known as somatotropin or growth hormone
Hormone formed in the frontal lobe of the pituitary. Its formation and release are controlled by the superior hormones ("releasing factors") SRH (for somatotropin releasing hormone) and somatostatin. Its release is increased by low blood sugar concentrations (hypoglycaemia), raised concentrations of aminoacids and glucagons and in sleep. glucose and cortisol reduce release.
The main actions are the increase in the biosynthesis of DNA (growth impulse), stimulation of the production of proteins, increase in blood sugar concentrations by opposition to the action of insulin and increase in gluconeogenesis (production of glucose) in the liver.
- StrainMicrobiology is the branch of science which deals with the conditions in which microorganisms live, including bacteria and viruses. Within microbiology, the strain is the systematic subunit of the species.
- Strokealso known as apoplexy or apoplectic insult
1. Ischaemic or dry cerebral infarction as a result of marked impairment or disappearance of arterial perfusion of areas of the brain. These make up about 80 % of strokes and are fatal in ca. 20 % of cases. Causes: Mostly embolism, initiated by arteriosclerotic changes (cf. arteriosclerosis) or from the heart (cardiac embolism). Rare causes include thrombosis which develops at the site of the cerebral infarct. Symptoms: Acute, depend on the vessels affects. The most frequent type of infarct is in the area served by the middle brain artery with paralysis on one side, loss of feeling and sometimes speech problems. 2. Primary wet stroke (ca. 20 % of cases, fatal in ca. 50 % of cases). This occurs after a cerebral artery has been torn open. Causes: Mostly vessel disease from arterial hypertension or hypertension. Rarer causes include abnormal coagulation with a tendency to bleed or malformation of the arteries. Symptoms: Mostly sudden, as in the ischaemic stroke, particularly loss of consciousness and headache. The two types of stroke may only be distinguished by computer tomography.
Neurological investigation, computer tomography of the brain (massive bleeding or cerebral infarct, site), ultrasound diagnosis (Doppler or duplex sonography) of the vessels serving the brain (constriction or occlusion)
Treatment should preferably in a clinic which specialises in stroke patients. Monitoring of breathing and circulation, early physiotherapy, in cases of ischaemic brain infarct, adjustment of the systolic blood pressure to more than 150 mm Hg, normalisation of blood sugar and reduction in fever, perhaps treatment of cerebral oedema, perhaps thrombolysis (dissolution by drugs of a blood clot) within the first 3-6 hours, perhaps operation if there is massive intracerebral bleeding or expanding infarct.
- subcutaneousbeneath the skin
- Sudden heart deathDeath within a few minutes as a result of sudden heart failure. The most frequent cause is coronary heart disease, with myocardial infarction and/or severe cardiac arrythmias.
- SulphonylureasSulphonylureas are oral antidiabetic drugs. They stimulate the B-cells of the islets of Langerhans in the pancreas and thus increase the release of insulin, the hormone which decreases blood sugar.
In non-insulin-dependent type 2 diabetes, when diet and weight loss are adequate to achieve metabolic control. Sulphonylureas however do not replace necessary dietetic measures or insulin treatment.
Undesired drug side-effects
Lowered concentrations of blood sugar (hypoglycaemia), problems in the digestive tract, rarely allergic reactions and changes in the development of blood cells.
- SweetenersNatural or synthetic compounds which are much sweeter than saccharose and which have no or negligible nutritional value (e.g. saccharin, acesulfam, cyclamate, aspartamate). Used particularly as sugar substitute in diets for diabetics and overweight subjects (see diabetes mellitus, overweight). Cf. sorbitol.
- Swelling of the Lymph NodesSee Lymphoma.
- Swelling of the Lymph Nodes in the NeckSwelling of the lymph nodes in the neck occurs in:
1. Inflammation of the lymph nodes in the area of the throat
2. Colonisation by tumour metastases (daughter growths) in the area of the throat or mouth
4. Infection with viruses (e.g. HIV, Epstein-Barr virus), bacteria or parasites (e.g. toxoplasmosis)
- Sympathetic nervous systemalso known as sympathicus
Sympathetic part of the vegetative (involuntary) nervous system, which consists of the sympathetic nervous trunk, which passes on both sides of the spinal column, and the corresponding sympathetic nerves and networks. The sympathetic nervous system includes nerve fibres for the transmission of pain from the intestine to the central nervous system. Stimulation of sympathetic nerves through fibres coming from the central nervous system leads to increases in blood pressure, heart rate and rate of respiration, widening of the pupils, erection of the hairs and sweating. The activity of the gastrointestinal muscles and the function of internal glands is decreased.
Drug actions on the sympathetic nervous system
1. Adrenalin, noradrenalin, ephedrine and other sympathomimetic drugs stimulate the sympathetic nervous system. 2. So-called sympatholytic drugs inhibit the activity of the sympathetic nervous system.
- Sympathomimetic drugsalso known as adrenoceptor agonists
Sympathomimetic drugs are drugs which imitate the action of the sympathetic nervous system.
1. Directly acting sympathomimetic drugs, such as adrenalin and noradrenalin, directly stimulate specific receptors . 2. Indirectly acting sympathomimetic drugs cause release of noradrenalin from the corresponding nerve cells. The released noradrenalin then stimulates the receptors of the sympathetic nervous system.
- Syndrome Xsee Syndrome, metabolic
- Syndrome, metabolicalso known as syndrome X
This occurs frequently in industrial countries and consists of a combination of 1. pathological overweight, 2. abnormalities in carbohydrate metabolism (e.g.type 2 diabetes), 3. raised blood fat values (see hypertriglyceridaemia) and 4. high blood pressure(hypertension). The combination of the four main symptoms is the so-called deadly quartet and brings a high risk of developing arteriosclerosis and other cardiovascular diseases.
- System, lymphaticName for cells (e.g. lymphocytes) which participate in the immune system. Lymphocytes are formed in the bone marrow and thymus; the reaction between lymphocytes and antigens takes place in the spleen and in the lymph nodes.
- Systolesee heart cycle
Glossary entries: Roche and Walter de Gruyter, Berlin