a silent period in the knocking sounds heard with a stethoscope over an artery, between the systolic and diastolic blood pressures, when the blood pressure is measured with a *sphygmomanometer.
Habitat: Wild as well as cultivated as an ornamental.
English: St. John's Lily, Poison Bulb.Ayurvedic: Naagadamani, Naa- gapatra, Sudarshana (var.). C. defixum Ker.-Gawl, is equated with Sukhadarshana.Siddha/Tamil: Vishamoongil.Action: Bulb—laxative (a substitute for ipecacuanha), expectorant. Used in biliousness, and in strangury and other urinary affections. Also used for the treatment of burns, whitlow and carbuncle. Fresh root—diaphoretic, emetic. Leaves— expectorant; externally, anti- inflammatory (used in skin diseases and for reducing inflammations). Seed—emmenagogue, diuretic.
The bark gave sterols and triter- penoids. Seeds contain alkaloids— lycorine, crinamine and crinasiatine.... crinum asiaticumThe only certain sign of death, however, is that the heart has stopped beating. To ensure that this is permanent, it is necessary to listen over the heart with a stethoscope, or directly with the ear, for at least ?ve minutes. Permanent stoppage of breathing should also be con?rmed by observing that a mirror held before the mouth shows no haze, or that a feather placed on the upper lip does not ?utter.
In the vast majority of cases there is no dif?culty in ensuring that death has occurred. The introduction of organ transplantation, however, and of more e?ective mechanical means of resuscitation, such as ventilators, whereby an individual’s heart can be kept beating almost inde?nitely, has raised diffculties in a minority of cases. To solve the problem in these cases the concept of ‘brain death’ has been introduced. In this context it has to be borne in mind that there is no legal de?nition of death. Death has traditionally been diagnosed by the irreversible cessation of respiration and heartbeat. In the Code of Practice drawn up in 1983 by a Working Party of the Health Departments of Great Britain and Northern Ireland, however, it is stated that ‘death can also be diagnosed by the irreversible cessation of brain-stem function’. This is described as ‘brain death’. The brain stem consists of the mid-brain, pons and medulla oblongata which contain the centres controlling the vital processes of the body such as consciousness, breathing and the beating of the heart (see BRAIN). This new concept of death, which has been widely accepted in medical and legal circles throughout the world, means that it is now legitimate to equate brain death with death; that the essential component of brain death is death of the brain stem; and that a dead brain stem can be reliably diagnosed at the bedside. (See GLASGOW COMA SCALE.)
Four points are important in determining the time that has elapsed since death. HYPOSTASIS, or congestion, begins to appear as livid spots on the back, often mistaken for bruises, three hours or more after death. This is due to the blood running into the vessels in the lowest parts. Loss of heat begins at once after death, and the body has become as cold as the surrounding air after 12 hours – although this is delayed by hot weather, death from ASPHYXIA, and some other causes. Rigidity, or rigor mortis, begins in six hours, takes another six to become fully established, remains for 12 hours and passes o? during the succeeding 12 hours. It comes on quickly when extreme exertion has been indulged in immediately before death; conversely it is slow in onset and slight in death from wasting diseases, and slight or absent in children. It begins in the small muscles of the eyelid and jaw and then spreads over the body. PUTREFACTION is variable in time of onset, but usually begins in 2–3 days, as a greenish tint over the abdomen.... death, signs of
Habitat: The rain forests of South India.
Folk: Gapasundi (Maharashtra), Boogri (Karnataka).Action: Stem-bark—antibacterial, antifungal.... pittosporum dasycaulon
The phenomenon occurs most commonly in chronic alcoholics suffering from Wernicke–Korsakoff syndrome.
It may also occur with head injuries.... confabulation
Disc prolapse may lead to pressure on a spinal nerve, causing pain. Injury to a nerve may lead to loss of sensation or movement in the area supplied by the nerve. (See also nerve injury; neuropathy.)... spinal nerves
The embryo develops upon one side of the ovum, its ?rst appearance consisting of a groove, the edges of which grow up and join to form a tube, which in turn develops into the brain and spinal cord. At the same time, a part of the ovum beneath this is becoming pinched o? to form the body, and within this the endoderm forms a second tube, which in time is changed in shape and lengthened to form the digestive canal. From the gut there grows out very early a process called the allantois, which attaches itself to the wall of the uterus, developing into the PLACENTA (afterbirth), a structure well supplied with blood vessels which draws nourishment from the mother’s circulation via the wall of the womb.
The remainder of the ovum – which within two weeks of conception has increased to about 2 mm (1/12 inch) in size – splits into an outer and inner shell, from the outer of which are developed two covering membranes, the chorion and amnion; while the inner constitutes the yolk sac, attached by a pedicle to the developing gut of the embryo. From two weeks after conception onwards, the various organs and limbs appear and grow. The human embryo at this stage is almost indistinguishable in appearance from the embryo of other animals. After around the middle of the second month, it begins to show a distinctly human form and then is called the fetus. The property of ‘life’ is present from the very beginning, although the movements of the fetus are not usually felt by the mother until the ?fth month.
During the ?rst few days after conception the eye begins to be formed, beginning as a cup-shaped outgrowth from the mid-brain, its lens being formed as a thickening in the skin. It is very soon followed by the beginnings of the nose and ear, both of which arise as pits on the surface, which increase in complexity and are joined by nerves that grow outward from the brain. These three organs of sense have practically their ?nal appearance as early as the beginning of the second month.
The body closes in from behind forwards, the sides growing forwards from the spinal region. In the neck, the growth takes the form of ?ve arches, similar to those which bear gills in ?shes. From the ?rst of these the lower jaw is formed; from the second the hyoid bone, all the arches uniting, and the gaps between them closing up by the end of the second month. At this time the head and neck have assumed quite a human appearance.
The digestive canal begins as a simple tube running from end to end of the embryo, but it grows in length and becomes twisted in various directions to form the stomach and bowels. The lungs and the liver arise from this tube as two little buds, which quickly increase in size and complexity. The kidneys also appear very early, but go through several changes before their ?nal form is reached.
The genital organs appear late. The swellings, which form the ovary in the female and the testicle (or testis) in the male, are produced in the region of the loins, and gradually descend to their ?nal positions. The external genitals are similar in the two sexes till the end of the third month, and the sex is not clearly distinguishable till late in the fourth month.
The blood vessels appear in the ovum even before the embryo. The heart, originally double, forms as a dilatation upon the arteries which later produce the aorta. These two hearts later fuse into one.
The limbs appear at about the end of the third week, as buds which increase quickly in length and split at their ends into ?ve parts, for ?ngers or toes. The bones at ?rst are formed of cartilage, in which true bone begins to appear during the third month. The average period of human gestation is 266 days – or 280 days from the ?rst day of the last menstrual period. The average birth weight of an infant born of a healthy mother (in the UK) is 3,200 g (see table).
The following table gives the average size and weight of the fetus at di?erent periods:
(See also PREGNANCY AND LABOUR.)... fetus
Forming the ball of the thumb and that of the little ?nger, and ?lling up the gaps between the metacarpal bones, are other muscles, which act to separate and bring together the ?ngers, and to bend them at their ?rst joints (knuckles).... hand
The 2 trochlear nerves arise in the brainstem, 1 on each side of the midbrain, and enter the eye sockets through gaps in the skull bones.
Each trochlear nerve controls 1 of the 2 superior oblique muscles, which rotate the eyes downwards and outwards.... trochlear nerve
Maintaining an up-to-date evidence base of ‘what works’ in public health and health improvements.
Providing useful information to health practitioners.
Commissioning research to remedy the gaps in the evidence base for medical practice.
Improving health promotion and advising on the standards for (and implementation of) public-health activities.
(See APPENDIX 7: STATUTORY ORGANISATIONS.)... health development agency (hda)
Habitat: Eastern Himalayas, Assam, West Bengal, Western Ghats, Travancore and the Andaman Islands.
English: Iron-wood, Mesu.Ayurvedic: Naagakeshara, Naa- gapushpa, Chaampeya, Naaga, Naagakinjalika, Ahipushpa. (In Ayurvedic Formulary of India Part I, revised edn 2003, Keshara and Kesara are equated with Mesua ferrea, while Kumkuma is equated with Crocus sativus.)Unani: Naarmushk.Siddha/Tamil: Sirunagappo, Nagakesaram. Sirunagappo also consists of the tender fruits of Cinamonum wighti Meissn. Malabar Naagakeshar consists of the fruits of Dillenia pentagyna Roxb.Action: Flower bud—antidysenteric. Flowers—astringent, haemostatic, anti-inflammatory, stomachic. Used in cough, bleeding piles, metrorrhagia. Essential oil from stamens—antibacterial, antifungal.
The Ayurvedic Pharmacopoeia of India recommends the use of dry stamens in gout, haemorrhagic disorders and diseases of the urinary bladder.The heartwood gave xanthones— euxanthone, mesuaxanthones A and B, which exhibit anti-inflammatory, CNS depressant and antimicrobial activities.Theseedoil gave4-phenylcoumarin analogues—mesuol, mammeigin, me- suagin, mammeisin and mesuone. Phenol-containing fraction of seed oil is antiasthmatic and antianaphylaxis.Stamens gave alpha- and beta-amy- rin, beta-sitosterol, biflavonoids, me- suaferrones A and B, and mesuanic acid. Stamens constitute the drug Naa- gakeshar of Indian medicine, used as an astringent, haemostatic, particularly in uterine bleeding and renal diseases.Ethanolic extract of the plant showed diuretic and hypotensive activity.Dosage: Dried stamens—1-3 g powder. (API, Vol. II.)... mesua ferreaThe nervous system contains billions of neurons, of which there are 3 main types: sensory neurons, which carry signals from sense receptors into the central nervous system (CNS); motor neurons, which carry signals from the CNS to muscles or glands; and interneurons, which form all the complex electrical circuitry within the CNS itself.
When a neuron transmits (“fires”) an electrical impulse, a chemical called a neurotransmitter is released from the axon terminals at synapses (junctions with other neurons). This neurotransmitter may make a muscle cell contract, cause an endocrine gland to release a hormone, or affect an adjacent neuron.
Different stimuli excite different types of neurons to fire. Sensory neurons, for example, may be excited by physical stimuli, such as cold or pressure. The activity of most neurons is controlled by the effects of neurotransmitters released from adjacent neurons. Certain neurotransmitters generate a sudden change in the balance of electrical potential inside and outside the cell (an “action potential”), which occurs at one point on the cell’s membrane and flows at high speed along it. Others stabilize neuronal membranes, preventing an action potential. Thus, the firing pattern of a neuron depends on the balance of excitatory and inhibitory influences acting on it.
If the cell body of a neuron is damaged or degenerates, the cell dies and is never replaced. A baby starts life with the maximum number of neurons, which decreases continuously thereafter.... neuron
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