The maxillary body emerge four major
processes; the palatine process, zygomatic and alveolar we have already described
and frontal process (ascending process). The frontal process is a bony plate,
with two faces, lateral and medial, which continues superiorly to the edge maxillary
anterior up to the frontal bone. The side face is covered by a vertical ridge, anterior
lacrimal crest, which extends up the ridge orbital. The ridge divides this face
on a part above, arranged under the skin, and a rear portion, orbital. In the
latter is a groove which is continuous below the nasolacrimal duct. The medial
part of the outer wall nostrils and presents a small transverse ridge where the
front end of the articulated means turbinate ethmoid (ethmoid crest) and lower
other similar (crest conchal) for the inferior turbinate. Bordes. By its
forward edge the frontal process articulates with the nasal bone. The trailing
edge (edge tear) It articulates with the lacrimal bone. The upper edge is articulated
the nasal edge of the front.
domingo, 28 de febrero de 2016
viernes, 26 de febrero de 2016
MUSCLE CONTRACTION
The concept of shrinkage is
different considering the isolated muscle fiber or the whole muscle belly. In
the case of muscle fiber contraction is It is shortening its active and depends
on the stimulation of the contractile machinery of the muscle fiber by the
action the nerve stimulation. However, the contraction of a muscle belly in
full does not necessarily mean that is shortened, and even if it is subjected
to resistance forces, the muscle belly can be extended. This is because the
muscles are divided into functional units, called motor units, which they are
formed by all muscle fibers which they are innervated by the same motor neuron.
Importantly, the distribution of fibers motor unit does not match the set
fascicles by intramuscular connective tissue. When a motor neuron fires all
fibers contract innervated by its axon, but not others. Thus, in the muscles
contract synchronously different units motor, that is, that, at a given moment,
in a muscle there is a variable number of motor units in contraction and
relaxation other. The amount of contraction of a muscle it depends on the
number of units motor are activated and frequency of stimuli motor neuron
emitting fibers. The action of Muscle considered as a whole (shortened,
lengthened or maintain their size) will depend on the number of units motor
which are contracting at all times, regarding the resistance to which is
subjected the whole muscle belly.
VASCULARIZATION OF MUSCLES
Each muscle belly receives one or
more own arteries accompanying veins, lymphatics and nerves. Typically, an
artery is larger caliber and called the main artery. Point vessel access is
usually the central or belly ends, and usually by the deep surface of the
muscle. Knowledge of the pattern of vascular pedicle input to the muscles of
considerable importance plastic surgery, because it is a key factor in
performing muscle grafts. Inside the muscle belly arteries accompanied veins
branch into tissue thickness intramuscular connective (perimysium) and arranged
with Under the direction of muscle fibers, establishing numerous anastomosis.
Capillary ramifications arteries are arranged at the level of endomysium and
around muscle fibers forming a capillary frame is more abundant in red muscle
fibers. Vascularity of tendons is much scarcer the muscle belly. The vessels
entering the tendon from the muscle belly and direct branches that address tendon.
Within the tendon, vascular ramifications They are arranged aligned with the
fiber material extracellular.
The lymphatic drainage of the
muscles begins in perimysium and accompanying blood vessels. An important
aspect of capillary blood and irrigation Muscle is its great adaptability to functional
needs. During the activity of a muscle, can increase its capillary
vascularization fibers up to 700 times in relation to the situation rest. This
regulatory effect of blood flow It seems to be enhanced by the existence of
anastomosis arteriovenous that, at rest, facilitate flow into the veins without
passing through the capillary bed. The irrigation deficiency causes fatigue and
muscle cramps (Painful spasms).
INNERVATION OF THE JOINTS
The joints are innervated so finely
branches Sensory peripheral nerves, such as nerve vegetative. The sensory
innervation of the joints of the peripheral nerves and tension and collects
information on stretching the fibrous capsule and ligaments. In Generally, the
origin of the sensory nerves of each joint It corresponds to nerve trunks that
innervate the muscles acting on the joint. Has been noted, in addition, the
areas of the joint being tightened under the action of muscles is innervated by
branches from trunks innervating antagonistic muscles of that action. This
peculiar topographic distribution of sensory and motor nerves it is very
suggestive the establishment of local reflex arcs adapt the muscle activity to
tension caused in the joint. Innervation of joints by vegetative nerves reaches
the joint accompanying vessels blood. The role of this innervation is not fully
clarified, but within its functions may include as follows: 1) collect some
information afferent Overvoltage and pain information; 2) regulate synovial
fluid production through its action on the vessels; and 3) have a trophic
effect on tissues joint. Vegetative nerve joint use a variety of neurotransmitters, among them They
include various neuropeptides such as neurokinin A (NKA), substance P (SP),
neuropeptide Y (NPY), and related neuropeptide calcitonin gene (CGRP).
SKIN INNERVATION
The skin is richly innervated by
sensory nerve fibers vegetative fibers and profusely branching through the
layers of the dermis (dermal nerve plexus). The sensory fibers (afferent) are
part of the and cutaneous nerves are peripheral extensions of the sensory
neurons of the dorsal root ganglia or some cranial ganglia. These fibers
originate from receivers skin as free nerve endings or specific sensory
corpuscles. Reflect the sensibility General skin (pressure, touch, pain,
temperature). also they originate, by nerve endings free, in hair follicles and
blood vessels. The fibers of the hair follicle and run along the surface inside
pods covering the hair root and contact with it on certain points. Vegetative
fibers are postganglionic sympathetic. They come from the chain ganglia latero vertebral
and reach the skin with cutaneous nerves or surrounding the cutaneous arteries.
Innervate blood vessels, glands sweat and erector muscles of hairs. In the
nerve terminal norepinephrine is released, except in the case of the sweat
glands, where neurotransmitter is acetylcholine. The sebaceous glands They are
not innervated; its activity is regulated by hormones androgenic, especially di
hydro testosterone.
NOMENCLATURE
Studying anatomy is learning a new
language with a very extensive vocabulary, and also learn to sort and relate
correctly the words of this vocabulary, Or, in other words, learn to "make
grammatical sentences and syntactically correct. " Most anatomical terms
come from Greek and Latin. As in other natural sciences, anatomical
nomenclature is written in Latin. Nevertheless, as national languages have
replaced Latin in the language of science, the terms Latinos anatomical
structures have been translated into the vernacular (Castilian, English,
German, French). The anatomical language requires clarity and precision, and be
as universal as possible. In the late nineteenth century there were more 30 000
anatomical terms to define structures body; Many of these words were repeats or
different names that were given the same structure in different countries, or
they were not properly verified data. The unification and clarifying the
anatomical language It required the development of a single nomenclature
(Payroll Anatomical). The first attempt at unification anatomical language was
held in 1895 in the city of Basel (Basel anatomical Payroll). Since then, Payroll
has always been in constant review and improvement. Payroll anatomical Jena (1935)
and anatomical Payroll Paris (1955) accounted Notable changes. In recent years,
the Federal Committee on Anatomical Terminology (FCAT), constituted in Rio de
Janeiro in 1989, he has made new adaptations of the nomenclature. In this work
we have used the Anglicized version 2001 of the Anatomical Payroll approved by
the FCAT. Without But we must be very aware that doctors not very interested in
these changes and continue to use past terms consecrated by use. Thus, in some
cases, it is important to include next to the name Official other terms
commonly used, we even eponyms.
jueves, 25 de febrero de 2016
ORGANIZATION OF THE HUMAN BODY
The human body, like any other
metazoan, It is made of cells. The cell is the structural unit essentials of
living organisms. In the human body more than 250 cell types are known which
represent a very small part of the millions of cell types that make up all
living beings planet. These structural elements are not isolated but closely to
build inter-agency alive. Between the cells and the whole organism no
intermediate levels of organization: tissues, organs and systems and devices. Tissues
are sets of cells which develop a particular function. There are four basic
types tissue: epithelial, connective, muscular and nervous; Y of them there are
specialized forms. Thus, within the tissue connective can be distinguished
adipose, cartilage, bone and blood. One feature of connective tissue cells is
well consists in largely by another structural element called extracellular
matrix. The extracellular matrix consists fibers and ground substance or
amorphous matrix. The fibers are composed of different proteins; stand including
several varieties of collagen (fibers collagen and reticulin fibers),
fibrillins (microfibrils) and elastin (elastic fibers). The amorphous matrix
contains liquid tissue (water, salts and small molecules) and, primarily,
glycosaminoglycans, proteoglycans and various glycoproteins. Bodies are formed
by different types of tissue. Are well defined anatomical units
exercising at least a function.
Thus, esophagus leads food into the stomach, kidney shaped urine but also it
produces substances that regulate the pressure blood and liver is an organ with
multiple functions metabolic. The organs are associated with appliances and
systems perform complex functions. An apparatus or system It can be defined as
a combination of parts to service a complex function, for example, digestion. There
is a tendency in the current anatomical terminology to exclude the term device.
However, in this work both terms are maintained. In the apparatus, organs They
are anatomically well defined, with limits accurate. In systems, the concept of
organ is more diffuse and macroscopic structures are hardly separable, for the
cellular and molecular elements that are no defined barriers or they overlap
throughout the body. Thus, it is easy delimit the urinary organs, but in the immune
system can not be separate bodies immune lymphoid cells isolated, and the
system nervous is, ultimately, a very complex cellular network that invades the
whole organism so diffuse. Equipment and systems that make up the human body They
are: 1) The skin and its annexes (integumentary system), 2) musculoskeletal
system, consisting of bones and cartilage (system Skeleton), joints (articular
system) muscles (muscular system), 3) the digestive system, 4) respiratory, 5)
urinary tract, 6) the device player or genital, 7) the endocrine system, 8) the
immune system, 9) the circulatory system, which encompasses the cardiovascular
system and the lymphatic system, 10) the nervous system. The organs do not
constitute a system or standalone device. They are receivers that capture and transform
information from the outside world form part of a continuum with the nervous
system. All systems work in a coordinated and structurally They can only be
separated as a method study to understand the overall unit is being alive. Underlying
these levels of organization of the body They are human molecules. The cells
are formed molecules, producing molecules and interact by molecules. Proteins
are the main molecules of which it depends on the structural organization and functional
living things. Themselves have their own and specific spatial organization
(anatomy). And the structure protein is specified by genes, which they are
fragments of the DNA molecule, whose organization space is essential for its
function again. The genes thus contain in coded form, the information the
structure of the organism, its cell types, their functions, their number and
spatial position of organization in tissues and organs, as well as signals for
development grow and die.
ANATOMY
The human anatomy is the science
that studies how and the structure of the human body. The term anatomy it's
very old. Derived from the Greek anatémnein (ana-volumes) hich means to cut through, meaning that assimilated
to dissect word (Latin dissecare, cut). In its origins and long, anatomy was
based only in dissecting the corpse. However, the Anatomy must face the living
subject, to the understanding of the forms and structures of the body alive.
Therefore, modern imaging techniques, which allow see inside the human body
without opening, are valuable tools for study of anatomy. According to the
method used, the anatomy can be descriptive, topographic, functional and
causal.Descriptive anatomy shows how the shape and structure of the parts of the
body. The topographic anatomy or regional divides the body into imaginary units
and conventional in order to establish relations space of structures. Anatomy seeks
functional correlation between forms the body and the functions they perform.
It is the intent to grasp the unity between the two modes with which the reality
of living matter is presented to our senses: form and function. Being
functional anatomy sets connecting links with other disciplines such as
physiology or molecular biology. The causal anatomy investigates how they
originated forms of organisms, studying individual development (developmental
anatomy) or species (phylogenetic evolutionary anatomy). Human anatomy that the
student must learn medicine and other health sciences, must be oriented
clinical practice. Clinical anatomy highlights anatomical data useful for
understanding the disease and to explore and properly treat patients. The
medical application of anatomy is extraordinarily importance. The objective is
achieved clinical anatomy when the student knows, for example, structures palpate
with his hands on a patient, where to put the stethoscope for listening to the
heart valves, recognize the interior of the larynx with a laryngoscope,
orientate properly on a radiograph, or deduct your imagination organs may be
injured when a subject has suffered a gunshot wound following a given path. But
also, and primordial form, when you know explain the consequences caused injury
to a particular anatomical structure (A nerve, an artery, etc.). One of the
essential features of life forms is the variability. No two individuals, not
two bodies, exactly equal. By the constitution, age, race and other factors,
human bodies offer variations like those of any other species. To describe the human
body, anatomy makes a morphological abstraction and defines an ideal human
type, a general pattern forms and structures. This human type considered the
norm, that is, the statistically most frequent. Deviations from the standard
forms are variations, anomalies and malformations.
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