The lungs are small and occupy only the dorsal portion of the thoracic cavity.
bancrofti is known to live in the lymphatic glands, and its embryos Microfilaria sanguinis hominis nocturna, passing by the thoracic duct, reach the blood-vessels and circulate in the blood.
The newly hatched insect closely resembles the parent, and the wing-rudiments appear externally on the second and third thoracic segments; but before the final moult the nymph remains quiescent, taking no food.
(2) Dorsals, those which begin with the first thoracic rib, and end at the last that is not fused with the ilium.
When first sucked up by the insect from an infected man it passes into its stomach, and thence makes its way into the thoracic muscles, and there for some time it grows.
Dorsal vertebrae frequently have a ventral outgrowth of the centrum; these hypapophyses may be simple vertical blades, I-shaped, or paired knobs; they serve for the attachment of the thoracic origin of the longus collianticus muscle, reaching their greatest development in Sphenisci and Colymbidae.
In many birds some of the thoracic vertebrae are more or less coOssified, in most pigeons for instance the 15th to 17th; in most Galli the last cervical and the next three or four thoracics are coalesced, &c. The pelvic vertebrae include of course the sacrum.
The most anterior part of the ilium often overlaps one or more short lumbar ribs and fuses with them, or even a long, complete thoracic rib.
In the region of the neck lateral strands pass through the transverse canal of the cervical vertebrae; but from the thoracic region onwards, where the cardiac branch to the heart is given off, each strand is double and the basal ganglia are successively connected with the next by a branch which runs ventrally over the capitulum of the rib, and by another which passes directly through the foramen or space formed between capitulum and tuberculum.
There are five pairs of larger sacs belonging to the pulmonary system: - (1) prebronchial or cervical, extending sometimes far up the neck, even into the cranial cavities; the throat-bags of the prairie fowls (Cupidonia and Pedioecetes) are a further development; (2) subbronchial or interclavicular; (3 and 4) anterior and posterior thoracic or intermediate; (5) abdominal sacs.
The ventral region of the thoracic skeleton is complex, each segment usually possessing a median sternum with paired episterna (in front) and epimera (behind).
The nervous system is remarkably concentrated in some beetles, the abdominal ganglia showing a tendency to become shifted forward and crowded together, and in certain chafers all the thoracic and abdominal ganglia are fused into a single nervecentre situated in the thorax, - a degree of specialization only matched in the insectan class among the Hemiptera and some muscid flies.
The head - carrying feelers, mandibles and two pairs of maxillae - is succeeded by the three thoracic segments, each bearing a pair of strong five-segmented legs, whose feet, like those of the adult, carry two claws.
For the appreciation of the sounds made by these stridulators, the ants are furnished with delicate organs of hearing (chordotonal organs) in the head, in the three thoracic and two of the abdominal segments and in the shins of the legs.
From these three pairs of thoracic legs comes the name - Hexapoda - which distinguishes the class.
- Legs and Ventral Thoracic Sclerites of Female Cockroach (Blatta).
The legs, wings and other organs of the trunk receive their nerves from the thoracic and abdominal ganglia, and the fusion of several pairs of these ganglia may be regarded as corresponding to a centralization of individuality.
ing the dorsal with the ventral sclerites of the Lateral thoracic abdomen, lessens t he capacity of the abdo ternal femoral minal region, while the contraction of the power Longit.
tergal ful muscles arising from the thoracic walls, and inserted into the proximal ends of the thighs, N.
From these facts it appears that the anterior three divisions of the head differ strongly from the posterior three, which greatly resemble thoracic segments; hence it has been thought possible that the anterior divisions may represent a primitive head, to which three segments and their leg-like appendages were subsequently added to form the head as it now exists.
Though the T hx, thoracic segments bear the wings, no trace of these appendages exists till the close of the embryonic life, 8 `' nor even, in many cases, till much later.
The thoracic segments, as seen in an early stage of the ventral plate, display in a well-marked manner the essential elements of the insect segment.
In the embryos of many insects there are projections from the segments of the abdomen similar, to a considerable extent, to the rudimentary thoracic legs.
The nervous system of the embryonic head exhibits three ganglionic masses, anterior to the thoracic ganglionic masses; these three masses subsequently amalgamate and form the sub-oesophageal ganglion, which supplies the trophal segments.
22) of the two hinder thoracic segments and are visible externally throughout the life-history, becoming larger after each moult or casting of the cuticle.
I., II., III., vomitories) the imaginal disks are to all the three thoracic segments appearance completely separated from of the larva; I, 2, 3, buds the hypodermis, with which they are, of the legs of the imago; la, however, really organically connected bud of head-lobes; f, of by strings or pedicels.
boring grub of a longhorn-beetle or of the saw-fly Sires, with its stumpy vestiges of thoracic legs; the large-headed but entirely legless, fleshy grub of a weevil; and the legless larva, with greatly reduced head, of a bee.
But the pupa hangs from the surface by means of paired respiratory trumpets on the prothorax, the dorsal thoracic surface, where the cuticle splits to allow the emergence of the fly, being thus directed towards the upper air.
Young resembling parents, but aquatic in habit, breathing dissolved air by thoracic tracheal gills.
Larvae eruciform without thoracic legs, or vermiform without head-capsule.
Insect wings are specialized outgrowths of certain thoracic segments, and are quite unrepresented in any other class of Arthropods.
The origin of insect wings remains, therefore, a mystery, deepened by the difficulty of imagining any probable use for thoracic outgrowths, comparable to the wingrudiments of the Exopterygota, in the early stages of their evolution.
As shown by the number and variety of species, the Orthoptera are the most dominant order of this group. Eminently terrestrial in habit, the differentiation of their fore-wings and hindwings can be traced from Carboniferous, isopteroid ancestors through intermediate Mesozoic forms. The Plecoptera resemble the Ephemeroptera and Odonata in the aquatic habits of their larvae, and by the occasional presence of tufted thoracic gills in the imago exhibit an aquatic character unknown in any other winged insects.
There are three distinct and large thoracic segments, whereof the prothorax is narrower than the others; the legs are much shorter and stouter than in the winged insect, with monomerous tarsi terminated by a single claw.
a, Restored thoracic limbs in transverse section of the animal; b, section across a posterior somite; c, section across one of the sub-terminal somites.
- Deiphon Forbesii, Dorsal view of second thoracic leg Barr.
st, Thoracic tracheal aperture.
His results, so far, have been confirmed by Starling, who finds that the amount of lymph-flow from the thoracic duct is dependent upon difference in pressure.
In the treatment of effusions into the pleura and, though with less advantage, of pericardial effusions, direct mechanical interference was practised by one physician and another, till these means of attaining rapid and complete cure took their places as indispensable, and were extended from thoracic diseases to those of the abdominal and other inner parts formerly beyond the reach of direct therapeutics.
The discovery of the Rntgen rays has also extended the physician's power of vision, as in cases of aortic aneurysm, and other thoracic diseases.
H, Head; 1, 2, 3, the thoracic segments; i., ii., the first and second abdominal segments; i., being the propodeum.
But the most natural division is obtained by the separation of the saw-flies as a primitive sub-order, characterized by the imperfect union of the first abdominal segment with the thorax, and by the broad base of the abdomen, so that there is no median constriction or " waist," and by the presence of thoracic legs - usually also of abdominal pro-legs - in the larva.
The soft, white larvae have the thoracic legs very small and feed in the stems of various plants.
The Tenthredinidae, or true saw-flies, are distinguished by two spines on each fore-shin, while the larvae are usually caterpillars, with three pairs of thoracic legs, and from six to eight pairs of abdominal prolegs, the latter not possessing the hooks found on the pro-legs of lepidopterous caterpillars.
In the adult there is a pair of such glands opening ventrally on the hindmost thoracic segment, or at the base of the abdomen; but in the young insect the glands are situated dorsally and open to the exterior on a variable number of the abdominal terga.
The Notonectidae breathe mostly through the thoracic spiracles; the air is conveyed to these from the tail-end, which is brought to the surface, along a kind of tunnel formed by overlapping hairs.
The name of shrimps is sometimes given to members of the order Schizopoda, which differ from most of the Macrura in having swimming branches or exopodites on the thoracic legs.
It may be objected that hereby the term pleon is used in two different senses, first applying to the abdomen alone and then to the abdomen plus the last thoracic segment.
To the left of the vena cava is the Spigelian lobe, which lies in front of the bodies of the tenth and eleventh thoracic vertebrae, the lesser sac of peritoneum, diaphragm and thoracic aorta intervening.
The cyst should be treated like a liver-abscess, by incision through the abdominal or thoracic wall, by circumferential suturing and by exploration and drainage.
Some of the families - the stone-flies, for example - have the young insect much like the adult, growing its wings visibly outside the thoracic segments, and active at all stages of its life.
A remarkable point in the Plecoptera is the presence in some forms (Pteronarcys) of small branching gills on the three thoracic and the front abdominal segments.
There are generally nineteen dorso-lumbar vertebrae (thirteen thoracic and six lumbar), the form of which varies in different genera; in the cursorial and leaping species the lumbar transverse processes are generally very long, and in the hares there are large compressed inferior spines, or hypapophyses.
The second thoracic ring is humped, and there is a spine-like horn or protuberance at the tail.
Io -r I cervical, 12-11 thoracic, 2 lumbar, 5-6 sacral, and 20 or 21 caudal, with a total caudal length of the Berlin specimen of 7 in.
The cervical and thoracic vertebrae seem to be biconcave; the cervical ribs are much reduced and were apparently still movable; the thoracic ribs are devoid of uncinate processes.
(Only seven of the The numbers appended to the eight thoracic somites are somites do not correspond to the visible, the first being fused enumeration adopted in the text.
10, sixth thoracic limb (second walking-leg) of female.
last thoracic limb of male.
13, sterna of the thoracic somites, from within.
3), this coalescence affects only the dorsal region of the thoracic somites, and the lateral portions of the carapace overhang on each side, enclosing a pair of chambers within which lie the gills.
7), except that the coalescence does not usually involve the posterior thoracic somites, several of which remain free, though they may be overlapped by the carapace.
Thus, in the thoracic limbs of the Malacostraca, the endopodite generally forms a walking-leg while the exopodite becomes a swimmingbranch or may disappear altogether.
- Squilla mantis bases tends to show that the primitive (Stomatopoda), showing the type of appendage was more complex last four thoracic (leg-bearthan the simple biramous limb, and ing) somites free from the some authorities have regarded the carapace.
It is highly characteristic of the Malacostraca, however, that the trunk-limbs are divided into two sharply defined tagmata corresponding to the thoracic and abdominal regions respectively, the limit between the two being marked by the position of the male genital openings.
The thoracic limbs have the endopodites converted, as a rule, into more or less efficient walking-legs, and the exopodites are often lost, while the abdominal limbs more generally preserve the biramous form and are, in the more primitive types, natatory.
In the thoracic series it is usual for one or more of the anterior pairs to be pressed into the service of the mouth, forming " foot-jaws " or maxillipeds.
In the primitive Malacostraca the gills were probably, as in the Phyllopoda and in Nebalia, the modified epipodites of the thoracic limbs, and this is the condition found in some Schizopoda.
In the Amphipoda, the gills though arising from the inner side of the bases of the thoracic legs are probably also epipodial in nature.
The gills are inserted at the base of the thoracic limbs, and lie within a pair of branchial chambers covered by the carapace.
These may be formed by the modification of almost any of the appendages, often the antennules or antennae or some of the thoracic limbs, or even the mandibular palps (some Ostracoda).
They are farthest forward in the case of the female organs of the Cirripedia, where the openings are on the first thoracic (fourth postoral) somite.
It is characteristic of the Malacostraca that the position of the genital apertures is constantly different in the two sexes, the female openings being on the sixth, and those of the male on the eighth thoracic somite.
In some Phyllopoda (A pus) egg-sacs are formed by modification of certain of the thoracic feet.
14), the posterior five or six thoracic somites have their development greatly retarded, and are still represented by a short unsegmented region of the body at a time when the abdominal somites are fully formed and even carry appendages.
t, Buds of thoracic s, Dorsal spine.
At the same time, the tendency to a retardation in the development of the posterior thoracic somites is very general in Malacostracan larvae, and may perhaps be correlated with the f
We need only mention the Mysis-stage (better termed Schizopodstage) found in many Macrura (as, for example, the lobster), which differs from the adult in having large natatory exopodites on the thoracic legs.
From both birds and reptiles the class is distinguished, so far at any rate as existing forms are concerned, by the following features: the absence of a nucleus in the red corpuscles of the blood, which are nearly always circular in outline; the free suspension of the lungs in a thoracic cavity, separated from the abdominal cavity by a muscular partition, or diaphragm, which is the chief agent in inflating the lungs in respiration; the aorta, or main artery, forming but a single arch after leaving the heart, which curves over the left terminal division of the windpipe, or bronchus; the presence of more or fewer hairs on the skin and the absence of feathers; the greater development of the bridge, or commissure, connecting the two halves of the brain, which usually forms a complete corpus callosum, or displays an unusually large size of its anterior portion; the presence of a fully developed larynx at the upper end of the trachea or windpipe, accompanied by the absence of a syrinx, or expansion, near the lower end of the same; the circumstance that each half of the lower jaw (except perhaps at a very early stage of development) consists of a single piece articulating posteriorly with the squamosal element of the skull without the intervention of a separate quadrate bone; the absence of prefrontal bones in the skull; the presence of a pair of lateral knobs, or condyles (in place of a single median one), on the occipital aspect of the skull for articulation with the first vertebra; and, lastly, the very obvious character of the female being provided with milk-glands, by the secretion of which the young (produced, except in the very lowest group, alive and not by means of externally hatched eggs) are nourished for some time after birth.
In Apus, as the figure shows, there are four of these " antenna-like " palps or filaments on the first thoracic limb.
- The second thoracic (fifth post-oral) appendage of the left side of Apus cancriformis, placed with its ventral or neural surface uppermost to compare with figs.
- The first thoracic (fourth post-oral) appendage of Apus cancriformis (right side).
The wings of Hexapoda are lateral expansions of the terga of the second and third thoracic somites.
Each consists in essence of a tightly stretched membrane or drum which is thrown into a state of rapid vibration by a powerful muscle attached to its inner surface and passing thence downwards to the floor of the thoracic cavity.
The spinous processes of the anterior thoracic region are high and compressed.
Aortic aneurysm or aortic dissection occurred in 18 %, usually in the thoracic aorta (about 60% ).
epidural catheters can be placed in either the cervical, thoracic or lumbar regions but lumbar epidural blockade is the most commonly used.
British Thoracic Society guidelines state that anyone who uses a bronchodilator three or more times a week should be treated with an anti-inflammatory drug.
Warde P, Payne D. Does thoracic irradiation improve survival and local control in limited-stage small-cell carcinoma of the lung?
Blood from the thoracic cavity may be used, provided the same precautions are taken.
cervical spine Spinal Causes Upper thoracic spine muscle spasm can often refer pain upwards to the neck region.
For CS, a block should extend from S4 to the upper thoracic dermatomes.
The tumor was located in the upper, middle and lower thoracic esophagus in four, 20 and 11 cases, respectively.
imaginal thoracic disks during Drosophila metamorphosis.
The region between these areas, the thoracic spine, is splinted by the rib cage and is relatively immobile.
Also work on the thoracic inlet to ease off the trapezius muscle.
For example:- Slouching for prolonged periods (see picture above) tends to encourage a round shouldered posture (exaggerated thoracic kyphosis ).
A small upper thoracic laminectomy is carried out and the anterolateral quadrant of the spinal cord is sectioned with specially designed blades.
activated lymphocytes pass into the blood stream via the thoracic duct.
spinal manipulation can be useful for the thoracic pain in the short term.
functional neuroanatomy of nitric oxide signaling in the thoracic nervous system of the locust L. Owens, Q.
Thoracic limbs lack pincers, branched and fringed with hairs, and mainly used for swimming.
The larvae or caterpillars have three pairs of thoracic (true) legs and several pairs of fleshy, abdominal prolegs.
The following 2 weeks will be focused on thoracic radiographs.
sacroiliac region, thoracic and cervical spine.
The first three morphological segments to appear are thoracic segments.
slouching in the upper thoracic area is the commonest cause of neck pain.
muscle spasm in the thoracic region can cause referred pain to radiate into the chest or abdomen.
It is usually better keeping the thoracic spine on the move.
A thoracic fracture is a break in the thoracic vertebrae.
thoracic aorta (about 60% ).
thoracic esophagus in four, 20 and 11 cases, respectively.
thoracic spine at about the end of August 1996.
thoracic aortic aneurysm is also always fatal.
Blood from the inferior thyroid, and internal thoracic arteries enters the thymus.
The treatment of lung cancer and other thoracic malignancies is one of the most complex and controversial topics in oncology.
tuberculosis of the thoracic spine: illustrated on a transverse section through the thorax.
Images concentrate on the bony landmarks and the major thoracic and abdominal viscera, the musculature and peripheral vasculature.
It currently includes brain, general neuro, thoracic viscera and the knee.
Ovi ositor gullet and a highly concentrated nervous 4' p system; in addition to the suboesophageal (side view) of Physo- ganglion, there are two thoracic ganglia pus.
(I) Amphicoelous; each end of the centrum is concave; this, the lowest condition, is embryonic, but was retained in Archaeopteryx and in the thoracic vertebrae of Ichthyornis.
The brachial plexus is formed by four or five of the lowest cervical nerves; the last nerve of this plexus often marks the boundary of the cervical and thoracic vertebrae.
Garrod, " Major Divisions of Passerine Birds (syrinx, &c.)," P.Z.S., 1876, pp. 506519; and " On the Conformation of the Thoracic Extremity of the Trachea in the Class A y es," P.Z.S., 18 79, pp. 357-3 80; Muller, Stimmorgane der Passerinen, Mailer's Arch.
It is a remarkable and newly-ascertained fact that in regeneration (in Potamilla) the thorax is not replaced by the growth of uninjured thoracic segments; but that the anterior segments of the abdomen take on the same characters, the setae dropping out and being replaced in accordance with the plan of the setae in the thorax of uninjured worms. Among the Oligochaeta the sexually mature worm is distinguished from the immature worm by the clitellum and by the development of genital setae.
A wing is an outgrowth from the dorsal and pleural regions of the thoracic segment that bears it, and microscopic examination shows it to consist of a double layer of cuticularized skin, the two layers being in contact except where they are thickened and folded to form the firm tubular nervures, which serve as a supporting framework for the wing membrane, enclose air-tubes, and convey blood.
A pair of ganglia in each thoracic segment is usual (fig.
21, e) or saw-fly, with its long cylindrical body, bearing the six shortened thoracic legs and a variable number of pairs of " pro-legs " on the abdomen (this being the eruciform type of larva); the soft, white, wood?
The discovery of the RÃ¶ntgen rays has also extended the physician's power of vision, as in cases of aortic aneurysm, and other thoracic diseases.
The nymphs of the Perlidae are closely like their parents and breathe dissolved air by means of tracheal gills on the thoracic segments, for they all live in the water of streams. They feed upon weaker aquatic creatures, such as the larvae of Mayflies.
In the Isopoda and Amphipoda, where, as a rule, all the thoracic somites except the first are distinct (fig.
8) and Cumacea (or Sympoda), however, leads to the conclusion that the coalescence of the first thoracic somite with the cephalon really involves a vestigial shell-fold, and, indeed, traces of this are said to be observed in the embryonic development of some Isopoda.
This modification is usually only found in the antennules and antennae, but it may exceptionally be found in the appendages of the trunk, as, for instance, in the thoracic legs of some Decapods (e.g.
In the Cumacea and Tanaidacea only the first thoracic limb has a branchial epipodite.
Among the Malacostraca some Schizopoda, the Cumacea, Tanaidacea, Isopoda and Amphipoda (sometimes grouped all together as Peracarida) have a marsupium or brood-pouch formed by overlapping plates attached to the bases of some of the thoracic legs.
Injections are commonly given in the lumbar region, sacroiliac region, thoracic and cervical spine.
Slouching in the upper thoracic area is the commonest cause of neck pain.
Muscle spasm in the thoracic region can cause referred pain to radiate into the chest or abdomen.
These nerves are derived from the coeliac plexus and the thoracic splanchnic nerves.
The claimant began to feel pain in his thoracic spine at about the end of August 1996.
An untreated ruptured thoracic aortic aneurysm is also always fatal.
Figure 2. CT scan features of tuberculosis of the thoracic spine: illustrated on a transverse section through the thorax.
Children with Marfan may develop kyphosis either in the upper (thoracic) spine or the lower (lumbar) spine.
The nerves of the brachial plexus are the fifth through the eighth cervical nerves (C5, C6, C7, and C8) and the first thoracic nerve (T1).
Klumpke's palsy or paralysis-A condition caused by an injury to the lower brachial plexus, involving the cervical nerves C7 and C8, and sometimes the thoracic nerve T1, causing weakness or paralysis in the hands and fingers.
American Thoracic Society. 1740 Broadway, New York, NY 10019.
Those in the thoracic or upper back region (T1 to T12) control signals to the torso and some parts of the arms.
It is a deformity of the thoracic spine (in the chest area, the vertebra to which ribs are attached) caused by abnormal centers of bone development at the intervertebral joints (physes).
(3) Opisthocoelous, or concave behind, only occasionally found in the thoracic region, e.g.
Larvae caterpillars with thoracic legs and abdominal prolegs.
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