局部解剖学讲义英文版Word文档下载推荐.docx

1、INTRODUCTION. The Basic Structures of the Human Body The human body is essentially constructed in layers. Form outside inwards, the structures met with a dissector are as follows:） The skin It covers the body surface and is composed of an epithelial layer of ectodermal origin, the epidermis, and a l

2、ayer of connective tissue of mesodermal origin, the dermis. It varies greatly in its thickness. As a rule, the skin is thin on the ventral （flectional） side and thick on the dorsal （extensional） side, but on the contrary, it is thicker on the palm and sole.） The superficial fascia It is a fibrous, f

3、atty covering that underlies the skin, so it is also called the subcutaneous tissue or subcutaneous fat. The fat is absent from the parts of the nipple and areola of the breast and some parts of the external genital organs. It is usually thick enough in women as secondary sex-character. The superfic

4、ial artery, vein, lymphatic vessel and cutaneous nerve are situated in this layer. In the head, neck, axilla and inguinal region, it also contains a number of superficial lymph nodes.） The deep fascia It is also called the proper fascia that lies under cover of the superficial fascia. It is thin but

5、 dense and strong collagenous membrane, forming sheaths for the muscles and affording them broad surfaces for attachment. In the limbs, it invests the entire limb, and gives off the septa which separates the various muscles and forms the intermuscular septa to separate the muscles in groups. It also

6、 forms the neurovascular sheaths to bound the nerves and vessels together along their courses. At the wrist and ankle, the investing fascia is thickened and is attached to the periosteum, forming the retinaculum, which hold the tendons in position. The deep fascia, intermuscular septa, bone together

7、 with the periosteum form the osteofascial compartment, which has an important clinical significance in the spread of infection in certain conditions.） The muscle Most of muscles met with in the dissection are the skeletal muscles. Their flesh part is called the belly, it is the active agent that pr

8、oduce movement. Each muscle has at least two attachments, the attachment that usually remains fixed is called the origin, the other one that moves is its insertion. The attachment of the muscle to bone （or other tissue ） is usually by a long cordlike tendon, or by a broad, relatively thin aponeurosi

9、s. Each muscle has its own blood supply, coming from the adjacent artery and has at least one nerve that contains the motor, sensory and autonomic fibers. The site of the nerve and artery entering the muscle is called the neurovascular hilus, it is important in the pediculate muscle grafting.） The i

10、nnermost layer The innermost layer of the limbs is the bones and joints, while in the dissection of the trunk, the innermost structures are the organs or viscera of the thorax, abdomen and pelvis. ） The following three kinds of structures may be found anywhere beneath the skin. 1. The blood vessels

11、The arteries are thick-walled elastic tubes. They were injected with coloured material beforehand. This procedure makes them more apparent and easily to be recognized. The veins are wider and thinner than their accompanying arteries. They usually retain the blood clots in their lumen, and are theref

12、ore bluish or purple in colour. In the superficial fascia, they do not accompany the arteries and are more numerous. All the middle sized deep arteries （e. g., the ulnar artery ） have two veins, one on each side, called the accompanying veins.2. The lymphatic vessels and lymph nodes The lymphatic ve

13、ssels are so thin and slender, so that, they are not detected during dissection, except for the main lymphatic trunks or ducts and some of the larger afferent or efferent lymph vessels of the principal groups of lymph nodes. The lymph nodes are small round or oval shaped bodies alongside the greater

14、 blood vessels （e. g., the jugular veins and the abdominal aorta）. Only a few lymph nodes are found in the superficial fascia. 3. The nerves They are white cords and branched like the arteries （but their branches often unite with each other）. With the exception of cutaneous nerves, they usually trav

15、el together with the blood vessels in a neurovascular bundle. The autonomic nerves in the thoracic or abdominal cavities are often running along the arteries and form a plexus around them to innervate the place where the artery supplies. The Cadaver and the Dissecting Laboratory） No one can deny tha

16、t the only way really to learn the anatomy of the human body is by dissection of the cadaver. A medical student should regard the opportunity to dissect the human body as a rare privilege. There is a great tendency for the different parts to dry out by evaporation, change colour, and become hard. If a part dries out, it can never be restored by wetting down, and dissection is impossible. The following methods fo