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.
- B-cellsAlso B-lymphocytes.
B-cells belong to the white blood cells. They are formed in bone marrow, lymph nodes, thymus and spleen. They have the function of producing antibodies during the immune response of the human body. They are the precursors of plasma cells.
- B-LymphocytesCf. B-cells.
- BacteriaBacteria are living creatures with a single cell which has no real nucleus. They may be shaped like balls (cocci), rods (bacilli) or screws (spirochaetes). Bacteria reproduce by cell division, which gives two identical cells. In unfavourable conditions, some bacteria can produce so-called spores (permanent stages), which makes them resistant to, for example, extreme temperatures. Many bacteria cause infections, while others are important components of the flora in the human skin and intestine.
- BasaliomaAlso basaloma or basal cell carcinoma
Semimalignant skin tumour. The basilioma grows slowly into the surrounding tissue, but does not form daughter tumours (metastases). It mostly occurs in parts of the body which are exposed to light (face, hands).
Forms: Many different forms, e.g.
1. Nodular, solid basalioma: transparent, waxy yellow to grey red, hemispherical tumours, covered with small dilated skin blood vessels (telangiectasia) and surrounded by rows of small nodules like beads; sometimes dead tissue in the centre.
2. Superficial basilioma: reddened surface which is covered with scales and a fine nodular border. Can occur in young patients on the trunk or from contact with arsenic.
3. Pigmented basilioma: basilioma with a high proportion of dark skin pigment, nodular or superficial. Can be confused with a malignant tumour of the pigment cells (malignant melanoma)
4. Sclerogenically growing basalioma: centre like a scar with small nodules at the edge, frequently recurs after removal.
5. Ulcerating basilioma: superficial basilioma which forms ulcers when it grows
6. Destructively growing basilioma: basilioma which grows downwards and which can destroy bone, cartilage or cerebral membranes
7. Pinkus tumour: special form of the basilioma
Therapy: Surgical removal, the edge of the cut should be in healthy tissue, possible X-radiation.
- Basealso known as alkalis
Chemical compounds which react basically or as alkalis. In aqueous solution they produce negatively charged OH ions. With acids they form salts and water. Bases stain red litmus paper blue and phenolphthalein solution red. The latter is the alkaline reaction when the pH is above 7. The term bases is also used collectively for purine and pyrimidine bases. These are components of the nucleosides and thus of the nucleic acids DNA and RNA.
- Bayliss effectRetraction of the smooth muscle of the blood vessel wall as a reaction to an increase in pressure in the vessel.
- BEDAbbreviation for binge eating disorder
Form of psychogenic eating disorder, in which subjectively uncontrollable attacks of eating occur at least twice a week over six months. A great deal is eaten randomly over a short period, until there is an unpleasant feeling of fullness, which is accompanied by feelings of guilt and shame. BED often occurs in combination with overweight and depression.
- Beet sugarsee saccharose
- Beta-blockerssee beta-receptor blockers
- Beta-receptor blockersalso known as beta-blockers, beta-sympatholytic drugs or beta-adrenolytic drugs
Drugs which inhibit the binding of noradrenalin and adrenalin to the (beta) receptors on the target organ.
1. In the heart, they inhibit the contractility of heart muscle, reduce heart rate and decrease the excitability of heart muscle tissue; 2. In the kidney, they reduce the release of the enzyme rennin; 3. In smooth muscle, they increase tension; 4. In the liver and skeletal muscle, they reduce glycogenolysis, which means the availability of glucose for energy extraction; 5. In fat, they inhibit lipolysis, the breakdown of fat to extract energy.
Particularly in arterial high blood pressure (hypertension), coronary heart disease, chronic heart failure (weakness of the heart muscle), also for cardiac arrythmias when the heart rate is increased, excessive thyroid function, to prevent migraine and locally for glaucoma.
Include decreased heart rate, tiredness and gastrointestinal problems. With diabetic patients there is increased risk of low sugar levels (hypoglycaemia),
Include very slow heart rate, low blood pressure and severe heart failure.
- BiguanidesDrugs for the oral treatment of type 2 diabetes (oral antidiabetic drugs).
Biguanides delay the intestinal uptake of glucose from food. They also inhibit the formation of glucose in the liver (gluconeogenesis) and stimulate the breakdown of glucose (glycolysis). In addition, they decrease the rate of other biochemical steps in the breakdown of glucose (in the respiratory chain). This can lead to an increase in the concentration of lactic acid. The resulting increase in blood acidity may be life threatening (lactate acidosis, cf. acidosis). The detailed mechanisms of action are unclear. If tissue supply with oxygen is deficient, biguanides may not be used.
Undesired drug side-effects
Include gastrointestinal problems
- BileAlso gallbladder fluid.
Bile is a green-brown fluid which is produced by the liver and stored and concentrated in the gallbladder. It consists of bile acids and special fats (phospholipids) which support the digestion of fats. Gallstones may form when the bile is highly concentrated or when there is inflammation.
- Bile acidsBile substances are formed in liver cells from cholesterol. The bile acids are re-used many times in the body; only a small proportion is excreted daily in the faeces. Bile acids are involved in the formation of emulsions during fat digestion. By displacing the pH they activate digestive enzymes in the intestine. They stimulate the digestive movements in the large intestine and inhibit those in the small intestine. Cf. lipid metabolism, digestion of neutral fats.
- Bile Duct CarcinomaRare and malignant tumour which originates in the bile ducts. Occurs most frequently in men and predominantly in patients of over 60. The tumour may lie within or outside the liver or be localised in the bile ducts. Metastases arise relatively late, as a result of spreading of the cancer cells through the blood or lymph.
Symptoms: Increasing jaundice, frequently accompanied by painless swelling in the right upper abdomen. Pain may develop in the pit of the stomach and weight may be lost.
Therapy: Treatment is surgical. Complete removal of the tumour (radical operation) is possible in only 10% of cases. Liver transplantation may be considered for isolated tumours.
Prognosis: The average life expectancy after radical operation is 12 months and ca. 2-6 months after operative palliative treatment.
- Bile DuctsThe bile ducts are a network of small vessels in which the bile is transported within the liver. The bile ducts come together outside the liver to form the right and left hepatic duct, which then form the common hepatic duct.
- BilirubinBreakdown product of a component of the red blood pigment (haemoglobin). Bilirubin is bound to a carrier in the liver and excreted in the bile into the intestine. In some liver diseases (e.g. acute hepatitis, chronic hepatitis and liver cirrhosis), excretion of bilirubin is disturbed and the levels are raised in the blood, in the skin and in the conjunctiva of the eye (see Icterus).
- BiologicsBiologics, or biopharmaceuticals are much more complex than the chemically clearly defined small molecules that still make up the majority of medicines. Biologics can be proteins (especially antibodies), DNA or RNA and are derived from living material using biotechnological processes.
- BiomarkerBiomarkers are measurable biological indicators that can be used to evaluate normal biologic and/or disease processes or responses to a drug or treatment.
This broad definition includes all diagnostic tests, imaging technologies and any other objective measure of a persons health status. Thus, biomarkers are not new, but because of a large number of new tools such as proteomics and genomics, researchers are discovering many novel markers that may have great applicability to improving drug development and healthcare.
- biopsythe removal and examination of tissues and cells from the living body
- BiosimilarsBiosimilars or follow-on biologics (FOBs).
A biosimilar is a new biological medicinal product claimed to be similar to a reference medicinal product which is submitted for marketing approval by an independent applicant after the patent for the originator product has expired.
While it is relatively easy to copy small chemical molecules, it is more of a challenge to copy biological products because the manufacturing processes, which involve living cells, are extremely complex and difficult to reproduce.
For this reason these second-wave products or second-entry biologics cannot be classified as generics. For this reason, the regulatory authorities are naming them similar biological medicinal products or biosimilars(Europe), and follow-on bioligics/proteins (USA).
- BiosynthesisSynthesis of organic compounds by living cells with the aim of maintaining the physiological function of the whole organism. Cf. metabolism
- BisphosphonatesBisphosphonates are drugs which regulate calcium metabolism (see calcium) and which are used therapeutically.
Bisphosphonates inhibit both the breakdown of bone by osteoclasts and the formation of new osteoclasts.
In tumours of the bone, when there are symptoms of raised calcium levels in the blood (hypercalcaemia syndrome), osteodystrophia deformans or osteoporosis.
- Blood lossReduced blood cell count and plasma volume in the circulation. The resulting signs and symptoms depend on the degree and rate of blood loss.
- Blood Poisoningsee sepsis
- Blood pressurePressure in the blood vessels and heart chambers. Strictly speaking, blood pressure is the arterial blood pressure measured in or on a peripheral artery in mm Hg (mm mercury) or kPa (Kilopascal, 1 mm Hg = 133.322 Pa) and which causes blood circulation. Blood pressure depends on the power of the heart and the resistance of the blood vessels and is subject to blood pressure regulation.
Systolic blood pressure
Blood pressure when the heart muscle contracts and develops tension. The heart systole is the highest point of the pressure curve during direct measurement of blood pressure.
Diastolic blood pressure
Blood pressure during relaxation and reduction in tension of cardiac muscle. The heart diastole is the lowest point in the pressure curve.
Blood pressure is given in the sequence systolic /diastolic blood pressure. Blood pressure is very different in different sections of the circulation. The pulsed fluctuations in pressure which are produced by the left heart ventricle (ca. 16/1.6 kPa or 120/12 mm Hg) are damped by the elastic so-called windkessel function of the aorta (ca. 16/10.7 kPa or 120/80 mm Hg). In the peripheral arteries, the amplitude of the pulses is large, as the systolic pressure rises as a result of wave reflection. When the arteries divide to form arterioles (arteries of small diameter) there is an increase in total cross-section, which results in a sharp drop in pressure, which continues in the capillaries, the so-called hair vessels. There is a further reduction in blood pressure in the large veins. In the right atrium there is the so-called central venous pressure. The pressure in the right heart ventricle is ca. 2.9/0.7 kPa or 22/5 mm Hg. The contraction of the right heart drives the blood through the pulmonary artery. This is the main artery of the lung and the pressure here is ca. 2.9/1.3 kPa or 22/10 mm Hg. The blood then passes through the vascular bed of the lungs into the left atrium, where the filling pressure for the left ventricle (the main chamber of the left heart) is ca. 1.1 kPa or 8 mm Hg. Cf. circulation of the blood.
- Blood Replacementalso haemotherapy
Therapeutic transmission (transfusion) of whole blood or certain components of the blood (red or white blood cells, clotting factors, blood plasma). Blood replacement is necessary for acute blood loss or when there is a deficiency in certain blood components.
Complications: During the transfusion of blood or blood components, infective agents such as hepatitis viruses or HI viruses can be transmitted. In addition, the recipient may develop an immune reaction or there may be increased deposition of iron from the transfused red blood cells.
- Blood sugarThe term blood sugar means the concentration of glucose in venous whole blood, capillary blood, blood plasma or blood serum. Glucose is transported by blood to the cells, in which it is broken down to produce energy (cf. glycolysis). Blood sugar concentration is regulated by the hormones insulin, glucagon, adrenalin, cortisol and STH. Blood sugar concentration normally lies between 3.6 and 5.6 mmol/l. Disease can lead to decreases (hypoglycaemia) or increases (hyperglycaemia) in blood sugar. Cf. type 2 diabetes, type 1 diabetes, glucose tolerance test.
- blood urea nitrogen (BUN)a test that measures the amount of nitrogen in the blood that comes from urea; it is used to assess the metabolic function of the liver and the excretory function of the kidneys
- BMIAbbreviation for body-mass index
- Body weightWeight which depends on height, age, nutrition and hormonal factors. The measured or actual body weight can be compared in tables with the desirable or normal weight for the age, sex and height. Individual deviations from the average values are frequent and may be pathological, as in marked overweight or anorexia. Cf. weight age, body-mass index, Broca formula.
- Body-mass-IndexAbbreviation BMI
Body mass number which is used for the evaluation of the body weight with respect to the maximum life expectancy or as a way of establishing overweight. The BMI is calculated from the body weight (kg) divided by the square of the height (m2). Alternatively, it can be read off from a nomogram (graphical scale system).The evaluation is influenced by age and sex. Cf. waist-hip ratio.
Classification of the BMI by the World Health Organisation WHO:
18.5 to 24.9 kg/m2: normal weight
25.0 to 29.9 kg/m2: overweight (Class I)
30.0 to 39.9 kg/m2. obesity or marked overweight (Class 2)
more than 40.0 kg/m2: morbid obesity or extreme overweight (Class 3)
- Bone MarrowBlood cells are produced in the bone marrow. Not only the red and the white blood cells (cf. phagocytes, T-lymphocytes, B-cells) are produced here, but also the blood platelets, which are involved in the coagulation of blood.
- Bone tissueApart from the teeth, the hardest structural component of the body (resistance to tension 10 kg/mm2, resistance to pressure 15 kg/mm2). Bone formation occurs as the result of so-called ossification.
The skeleton is the scaffolding for the body and consists of long, short and flat bones. The joints function as levers for the connected muscles. Bones, ligaments and skeletal musculature together form the so-called locomotor apparatus. In addition, the bones provide mechanical protection for the brain, spinal chord, sensory organs and bone marrow.
1. On the outside of the bone lies the periosteum ("bone skin"); 2. The bone substance consists of a solid outer zone (Substantia corticalis, Substantia compacta or Os compactum) and a spongy internal scaffolding of fine bars of bone, known as trabeculae. This spongy layer is known as the Substantia spongiosa or Os spongiosum; 3. The bone marrow (Medulla ossium) lies in the marrow cavity between the trabeculae. At birth, only bone marrow which forms red blood is present. In the course of life, this is gradually replaced by yellow fatty marrow and is only kept in a few bones, such as the ribs, breastbone, vertebral bodies, wrist and elbow bones, the flat bones in the skull and the ileal crest.
The intracellular substance lies between the bone cells (osteocytes) and consists of collagen fibres and calcified ground substance. The intracellular substance is either arranged in lamellae (plates) (lamellar bone tissue) or is disordered (woven bone).
- Bone tissue remodellingName for the process of permanent bone restructuring, in which the osteoclasts, the cells which break bone down, form hollows in the inner surface of the bone, which are then filled in again by the osteoblasts, the cells which form bone. An imbalance between the formation and breakdown of bone is regarded as a cause of the development of osteoporosis (coupling hypothesis). Cf. ossification
- Bone tumoursBone tumours are growths in bone tissue. A distinction is made between primary bone tumours which originate in the bone itself and secondary bone tumours, which are bone metastases of other tumours, and tumour-like bone defects.
Primary bone tumours can be distinguished on the basis of their benign or malignant character
1) benign and slowly growing tumours (e.g. enchondroma, osteoidosteoma, osteochondroma)
2) semimalignant tumours, which destroy the surrounding tissue, but which do not tend to form metastases
3) malignant tumours which grow slowly and form metastases later
4) highly malignant tumours which metabolise early (e.g. Ewings sarcoma, osteosarcoma)
With secondary bone tumours, a distinction is made between so-called osteoplastic matastases, in which new bone mass is formed (e.g. in breast cancer and prostate carcinoma) and so-called osteoclastic or osteolytic metastases, in which bone is broken down (e.g. in bronchial carcinoma, renal carcinoma, thyroid carcinoma).
Symptoms: The symptoms of bone tumours are mostly unspecific. Pain, fever, increase in the count of white blood cells and other blood parameters (phosphatases) can occur. Spontaneous bone fractures can also occur.
Diagnosis: Diagnosis is carried out with the help of X-rays. Typical changes are found in the X-rays, such as bone defects with indistinct edges, changes in the periost. This is complemented by using image sectioning procedures, such as tomography, computer tomography, nuclear spin tomography and also scintigraphy (imaging of the whole skeleton) and angiography (imaging the blood vessels). Microscopic investigation of tumour tissue samples is also used.
- Borderline hypertensionName for slightly raised blood pressure (systolic 140-159 mm Hg, diastolic 90-94 mm Hg). Cf. hypertension.
- Bowman¿s capsulethe part of a nephron that surrounds the glomerulus and receives the glomerular filtrate
- Broca-FormulaFormula developed by the French surgeon Pierre P. Broca (1824-1880) to assess the normal body weight of adults. Within 10-20% in either direction, the normal weight corresponds to the height in cm minus 100.
- BronchiolesBronchioles are fine branches of the bronchi. They have a diameter of 0.7-1 mm. Their wall is free of cartilage and glands, but contains many elastic fibres and helically structured smooth musculature. Bronchioles are covered with ciliated epithelium, but without mucus-secreting beaker cells.
- Bronchitis, acuteAcute inflammatory infection of the lower respiratory tract (cf. bronchus), mostly as a consequence of viral infection. Bacterial bronchitis is relatively rare.
Cough, thick sputum, increase in body temperature, pain in the chest.
Fluid intake, measures to stop the mucous membranes from swelling, antiviral therapy (virostatic drugs) only in exceptional cases. Antibiotics only for bacterial infection (e.g. from haemophilus influenzae), perhaps drugs to lower temperature. Natural medicines include drugs to dissolve phlegm, for example as teas to protect the mucous membrane; ethereal oils increase secretion, dissolve phlegm and have antibacterial activity. They can be used externally as medicinal baths, embrocations or for inhalation. Moist chest compresses are thought to soothe, to inhibit cough and to alleviate pain.
- BronchusLower respiratory tracts; continuation of the trachea (windpipe). Before the 4th thoracic vertebra, the bronchus divides into the right and left main bronchi. The main bronchi then branch into the lobes of the lung, with three lobe bronchi on the right and two on the left. These then branch into segmental bronchi, corresponding to the number of lung segments.
The wall of the bronchi is covered with a ciliated epithelium. In the wall of the ciliated epithelium there are beaker cells which secrete mucus, which is transported in the direction of the throat by the cilia. In this way, foreign particles are transported out of the bronchi. Bronchial musculature is smooth and circular and forms helixes in the smaller bronchi. Cf. bronchioles.
- BSAbbreviation for blood sugar
- buffersubstances (such as bicarbonates and some proteins in biological fluids) that neutralise acids and bases to maintain a certain pH range
- BulimiaBulimia is the name of a psychogenic eating disorder, in which excessive quantities of food, which is often very rich in calories, are eaten in a short time (eating attack). After this measures are taken to keep the body weight in a normal or subnormal range. These may include periodic fasting, extreme physical activity, self-induced vomiting or misuse of laxatives and diuretics, with corresponding complications. The incidence is estimated to be 1-3 % in women and ca. 0.01 % in men between 18 and 35 years. The development of bulimia is frequently preceded by pathological overweight or anorexia.
Psychotherapy (e.g. behavioural therapy).
- Bulimia nervosasee bulimia
Glossary entries: Roche and Walter de Gruyter, Berlin