The distinction which he draws between the sensory andtrophic layers on the one hand, and the motor-germinative layer on the other, is entirely a histological one.
Now between the upper or sensory layer and the lower or trophic layer there exists, in spite of their very different functions, a close histological likeness, for both are essentially epithelial layers.
Then at a somewhat higher level, self-differentiation, and the trophicreaction to functional stimuli.
All the trophic (nutritive) processes, without exception, are subject to the law of substance.
There is also a trophic differentiation, the fibres undertaking special functions of nutrition (the conduction of the sap).
According to Crocker in some cases they can be shown to be a part of trophic changes.
This makes the cause, according to Eyles, an inflammatory and trophic phenomenon due mainly to changes following pressure on the vasomotor nerves.
The trophic causes of inflammation are those whose action is supposed to take place through the influence of nerves.
Some physiologists actually talk of there being {244} trophic fibers in the nerves, though it would seem more reasonable to think that the nerve trophic effect comes from the modification of the circulation to the part.
It is probable that the nerves themselves have a trophic or nutritional--that is, vitalizing--influence upon muscles.
Other trophic centres, governing nerve tracts in the spinal cord itself, are in the various regions of the brain.
Certain cells of the anterior part of the spinal cord, for example, are the trophic centres of the spinal motor nerves.
This condition is due to trophicdisorders of the nails.
In such cases, the trophic state of the muscles and their contractibility being unequal, there is a resultant asymmetry, especially evident in the play of facial expression.
Pressure sores and perforating ulcer of the foot are the most important trophic phenomena.
A nerve also exerts a trophicinfluence on the tissues in which it is distributed.
In addition to vasomotor and trophic changes, there is often severe pain of a burning kind (causalgia or thermalgia) which comes on about a fortnight after the injury and causes intense and continuous suffering which may last for months.
In course of time the foot becomes inverted and the toes are pointed--pes equino-varus--and trophic sores are liable to form.
The acute bed-sore is a rapidly progressing form of ulceration, often amounting to gangrene, of portions of skin exposed to pressure when theirtrophic nerve-supply has been interfered with.
There may also develop trophic changes such as blisters, superficial ulcers, and clubbing of the tips of the fingers.
It is most pronounced in lesions of the motor nerve-trunks, probably because vaso-motor and trophic fibres are involved as well as those that are purely motor in function.
There then follows an improvement or disappearance of any trophic disturbances that may be present.
It is to be attributed partly to want of use, but chiefly to reflex interference with the trophic innervation of the muscles.
In the distal end, it extends throughout the entire peripheral distribution of the nerve, and appears to be due to the cutting off of the fibres from their trophic nerve cells in the spinal medulla.
Bed-sores and other trophic changes are common, and there is the usual risk of complications in relation to the urinary tract.
In most cases, however, there are paralytic symptoms referable to the lower extremities, the bladder, and the rectum, and there may also be trophic disturbances in the parts below.
Interference with the trophic nerve supply may play a part, as cases are recorded by Bognaud in which union of fractures of the leg failed to take place after injuries of the spinal medulla causing paraplegia.
Great care in nursing is necessary to prevent trophic sores occurring over parts subjected to pressure, such as the sacrum, the scapulæ, the heels, and the elbows.
As the bladder is unable to empty itself, and its trophic nerve supply is interfered with, the use of the catheter involves considerable risk of infection, unless the most rigid precautions are adopted.
It is of course in cases of spasm and other convulsive phenomena dependent on structural disease of nerve centres or conductors that such trophic disturbances are most liable to occur.
They are unaccompanied by any alteration in sensation, in the reflexes, or in the trophic functions.
Forms in which schizogonic reproduction is of general occurrence during the extra-cellular, trophic phase.
Leger thinks that this partition most likely owes its origin to trophic considerations, i.
This elimination of a part of the nuclear material (to be distinguished as trophic or somatic, from the functional or germinal portion, which forms the sexual nuclei) may occur at widely-different periods.
I do not believe that we can wait for detailed knowledge of population sizes, or ecology, or demography, or trophic importance, or any other biological attribute of these birds before we start conservation and management.
Another comparison is shown in Table 17, where the species in each community are categorized according to the number feeding at each trophic level.
Second, no study has considered the trophic relationships of an entire seabird community, i.
The trophic roles played by seabirds must be studied in detail at the community level year-round before those analyses can be properly refined.
Finally, few investigators have attempted to fit birds into an entire ecosystem, including lower trophic level origins as well as fish, marine mammals, and man.
Number of species feeding at different trophic levels within seabird communities and habitats of the northeastern North Pacific Ocean and Bering Sea.
Wayne Campbell 73 The Biology and Ecology of Marine Birds in the North 93 Trophic Relations of Seabirds in the Northeastern Pacific Ocean and Bering Sea, by David G.
Information contained in Tables 11-15 can be summarized to show characteristics of seabird trophic relations.
These sorts of studies will serve to bring the role of seabirds into perspective with other upper trophic level feeders.
Strong, persistent impressions or suggestions made on the reflex organic consciousness of the inferior centers may modify their functional disposition, induce trophic changes, and even change organic structures.
Sollier is said to have been the first to remark trophic bone disorders in cases of neuropathic contracture.
True trophic disorders of the skin, hair, and bones observed in the reflex cases are also said to have no place in the illustrations of pithiatism.
There were marked trophic disturbances of the right foot and of the lower third of the lower leg.
The X-ray showed a decalcification of all the bones of the hand and wrist; trophic disturbance of the small carpal bones although the trauma had affected only the second interosseous space.
Right leg entirely anesthetic; left leg and both arms showed a diminution of sensibility; suggestion of glove and stocking anesthesia; trophic changes absent.
There were no trophicvasomotor or secretory disturbances.
In short, we return to the old doctrine of reflex paralysis, conceiving that a stimulus passing from the periphery influences the gray matter in its trophic functions.
Re bone changes, Babinski enumerates trophic changes in the tissue of bones and joints amongst objective signs that permit us to distinguish the reflex or physiopathic disorders from the hysterical or pithiatic disorders.
Bed-sores in sacral region developed during the first two days, and seventeen days later well-developed serpiginous trophic sores developed on the outer side of each leg and continued to increase slowly until death.
In a few instances large blebs rose on the back of the hand, or patches of vesicles appeared over the terminal distribution of the nerve, pointing to early trophic changes.
Again, the peroneal nerve symptoms were more obstinate and prolonged, and instances of ascending neuritis were more common than in the case of any other nerve of the lower extremity, and the trophic wasting of muscles was more marked.
A largetrophic sacral bed-sore steadily increased in depth and size.
No wasting of the interossei, skin normal except for a large trophic blister on the dorsum of the hand.
Early trophic sacral bed-sores developed and steadily increased in depth and extent, slighter ones developed on the heels.
Trophic sores were both early to develop, and extensive; primary decubitus occurred in all the cases I saw, and steady extension followed.
In the smaller sensory trunks it was often evidenced by the occurrence of neuralgic pain, especially liable to be influenced by climatic changes; in the larger, by signs of more or less severe motor, sensory, and trophic disturbance.
The nature of the nervous influence (whether ordinary vaso-motor only, or a special trophic function) has been greatly disputed.
This was remarkably exemplified in a case which was under my care some years ago, and in which both eyes were greatly damaged by vaso-motor and trophic changes; partial insanity also supervened with hallucinations of sight and hearing.
The patient, a man sixty-five years old at the time of his death, had suffered for several years from the most violent and intractable epileptiform trigeminal neuralgia, complicated with interesting trophic changes of the tissues.
It may produce trophic changes, either in the direction of simple atrophy or of subacute inflammation with proliferation of lowly-vitalized tissue (e.
As a consequence of the persistent hyperemia, too many trophic impulses are sent down.
Nervous people are, most occupied with those parts of the brain which have something to do with the omission and transmission of trophic influence to particular parts of the body.
Such impressional changes as we have referred to, if produced after this, must be in the nature of backward growth or an inversion of trophic influences or a great perversion of embryonic life.
Just as soon as the mind's inhibitory action was taken off them by the persuasion that there was nothing the matter with them the patient proceeded to get well, gradually progressive use bringing back the normal trophic condition.
In these, the early symptoms were pains or aches in the arm followed by some weakness of muscles and even some trophic disturbances.
The Nerve+ theory, which is the one most commonly accepted, is that perforating ulcer is always of trophic origin and depends upon a chronic peripheral neuritis.
This explains the various trophic disturbances which are very often observed, such as epithelial growth, not only in the vicinity of the ulcer, but occasionally over the entire foot and leg; also eczema, erythema and excessive perspiration.
Vasomotor nerves supply the coats of most blood vessels of the skin, and trophic nerves are everywhere controlling the nutrition of each part.
According to present physiological doctrine, the exciting cause of rheumatism, cold, either acts directly upon the vaso-motor or the trophic (?
Some refer the origin to the secretion of an excessively acid gastric juice under abnormal nervous influence (Gunsburg), others to vaso-motor disturbances, and others to trophic disturbances.
If this occurs all trophic and schizogonic phases are forthwith digested, and the survival of the sexual phases depends entirely upon whether the insect is a gnat or mosquito.
With the lapse of time all trophic and schizogonic (asexual) phases of the parasite in the blood die off.
They are invariably blood parasites, and for part or all of the trophic period come into intimate relation with the cellular elements in the blood.
In this manner they explain burns through suggestion, stigmata, trophic changes of a miraculous appearance, etc.
In the higher animals and in primitive man, according to them, all trophicactions entered consciousness and were regulated by it.
Arrest of development occurs between the fourth and fifth month, owing to the trophic nerve centres being affected by the malnutrition of the mother.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "trophic" in a variety of sentences. We hope that you will now be able to make sentences using this word.
