Knowledge points of Pathology

2021-04-30 23:00:33  作者:Photography

Three laws of disease occurrence : Damage and anti damage ; Cause effect transformation ; Local and global .

Five indicators of brain death : Autonomous breathing stops ; Irreversible deep coma , No response to external stimuli ; The brainstem reflex disappeared ; The electroencephalogram showed a continuous flat waveform ; Autonomic muscle activity completely disappeared .( Spontaneous breathing and brainstem reflexes are still there — Vegetative state )

atrophy : Systemic —— Chronic wasting disease and advanced cancer

Locality —— Malnutrition, atrophy ; Atherosclerosis causes heart and kidney atrophy ;

Compression atrophy ; Hydronephrosis causes renal parenchyma atrophy for a long time ;

Disuse atrophy ; Long term immobility of limbs after fracture causes muscle atrophy ;

Denervation atrophy ; The nerves in the brain and spinal cord cause muscle atrophy ;

Endocrine atrophy ; Sheehan syndrome ( Decreased endocrine function , The target organ lacks normal stimulation )

Metaplasia type : It only occurs in homologous tissues , That is, between epithelial tissue and mesenchymal tissue 、

① Squamous metaplasia : Columnar epithelium ( Bronchial epithelium )、 The transitional epithelium is transformed into squamous epithelium ;

② Intestinal metaplasia : Chronic atrophic gastritis , Intestinal metaplasia occurs in the epithelium of gastric mucosa ;

③ Metaplasia of mesenchymal tissue : Fibrous tissue metaplasia into cartilage or bone tissue ( Myositis ossificans )

Physiological significance :① Enhance local resistance to stimulation ;

② Reduce the intrinsic function of local tissue ;

③ If the cause of metaplasia persists, it will lead to malignant transformation .

Cell edema : Liver, kidney and heart ; With the naked eye : The larger the volume, the more the mass , The color is pale , The edge is round and blunt .

Under the mirror : Early stage of the disease , There are red stained granules in the cytoplasm , These are swollen mitochondria and endoplasmic reticulum , Therefore, it is called granular metamorphosis ;

Serious times , The cells swell , The cytoplasm is loose and transparent , The nucleus swells , It's called balloon like change or water like change , Like viral hepatitis .

Vitreous degeneration : Three types :① connective tissue ( Scar tissue ; Atherosclerotic fibrous plaques ; Necrotic tissue )

② The wall of the arteriole ( Benign hypertension , Small arteries in the kidney, brain and spleen of diabetes )

③ Intracellular ( Tubular epithelial cells ; Alcoholic liver disease is liver cells )

Pathological changes of necrotic nuclei : Nuclear condensation ; Nuclear fragmentation ; Nuclear dissolution .

The type of necrosis :① Coagulation necrosis - Heart, liver, kidney, spleen and other parenchymal organs ;

- With the naked eye - Gray, gray, yellow , It's tough , The boundaries are clear , Hyperemia and bleeding ;

- Under the mirror - The cell microstructure disappeared , The tissue profile exists for a certain period of time .

② Liquefying necrosis - Tissue rich in water and phospholipids ; An abscess caused by encephalomalacia or bacterial infection ;

③ Celluloid necrosis - Microscopically, it's filamentous 、 Granular ;

- rheumatism 、 Malignant hypertension ;

④ Caseous necrosis - Tuberculosis , There is more lipid in the lesion ;

- With the naked eye - Light yellow , It looks like cheese , Soft ; The original structure disappears .

⑤ Gangrene - Name explanation : Extensive tissue necrosis accompanied by putrefactive bacteria infection , Make necrotic tissue dark brown ;

type :1. Dryness - The end of a limb with blocked arteries but still unobstructed venous return ; The necrotic area is dry and black , The boundaries are clear , The infection of spoilage bacteria is mild ;

2. Wettability - Organs connected with the outside world ( Lung, intestine, uterus, appendix ) Or limbs with blocked arteries and blocked venous return ; There is more water in the necrotic area , The swelling is obvious , It's dark green , The boundaries are not clear , Spoilage bacteria reproduce .

3. Gas nature - Open wounds deep into the muscles ; Clostridium perfringens .

The ending : Dissolution absorption ; Separate and discharge ; Mechanization ; The parcel 、 calcification .

The ability of tissue cells to regenerate :1. Unstable cells : Epidermis 、 lymph 、 Hematopoiesis 、 Mucous membrane 、 Epithelial cells of glands ;

Stable cells : Gland ( Liver, kidney, pancreas, sweat gland, sebaceous gland ) The parenchymal cells and the mesenchymal tissue cells of ( Fibroblasts 、 Osteoma 、 Chondroma 、 Smooth muscle 、 Endothelium );

Permanent cells : Nerve cells 、 Skeletal muscle and cardiomyocytes .

Granulation tissue : Definition - Refers to the immature connective tissue composed of new capillaries and fibroblasts

composition : New capillaries ; Fibroblasts ; Inflammatory cells ;

effect :1. Anti infection , Protect the wound ;

2. Filling wounds and other tissue defects ;

3. Planning or wrapping up necrotic tissue 、 Blood clots 、 Inflammatory exudates and other foreign bodies ;

The ending : Scar tissue

The third chapter Local blood circulation disorder

The consequences of congestion : Congestion edema ; Congestion bleeding ; Parenchymal cell damage ; Congestive sclerosis .

Pulmonary congestion : Left heart failure is , Left ventricular output is reduced , Left intracardiac blood volume increased , The pulmonary venous return is blocked , Cause pulmonary congestion ;

Acute pulmonary congestion : Lung volume increases , The color is dark red , And it starts with red foam liquid outflow ; Under the light microscope : Bronchiectasis and congestion of alveolar septum , It may be accompanied by alveolar septal edema , Part of the alveolar cavity is filled with edematous fluid and leaked red blood cells ;

Chronic pulmonary congestion : Increase in volume , Weight gain , The color is dark red , The texture hardens ;

In the mirror : Alveolar wall thickening and fibrosis , There is light red edematous fluid in alveolar cavity , There are also a lot of macrophages containing hemosiderin granules, namely heart failure cells , The capillaries in the alveolar wall dilate and congest .

Congestion of liver : Right heart failure , Right ventricular output decreased , Blood volume in the right ventricle increased , Hepatic venous reflux is blocked , Cause liver congestion

Acute liver congestion : Increase in volume , It's dark red ; Under the light microscope : The central lobular vein and hepatic sinuses were dilated and congested , In severe cases, central lobular necrosis can be seen , Hepatic steatosis occurs in the portal area ;

Chronic liver congestion : Increase in volume , Weight gain , It's dark red , The texture becomes solid . There are red and yellow patterns on the section , It looks like a section of areca nut , So it's called areca liver .

In the mirror : The central vein of hepatic lobule and the hepatic sinuses nearby were highly dilated and congestion 、 Hemorrhage . Hepatocytes in the central area of hepatic lobule atrophy or even disappear due to hypoxia and compression , Steatosis of hepatocytes around lobules .

The conditions for thrombosis : Cardiovascular endothelial cell damage ; Changes in blood flow ; The hypercoagulable state of the blood .

The type of thrombus : Platelet aggregation is the first step in thrombosis .

① White thrombus : Platelets adhere to the damaged endocardium , And growing .( Acute rheumatic endocarditis )

Naked eye : Grey white , Rough surface , Hard , It adheres closely to the wall of the blood vessel ;

Light mirror : It's made up of platelets and a small amount of cellulose , It's usually located in the heart valve with faster blood flow 、 In the heart cavity and arteries . In the vein , The white thrombus is located at the beginning of the thrombus , It's the head that forms the persistent thrombus .

② Mixed thrombi : A thrombus formed by the interlacing of pale platelets, cellulose layer and dark red red red blood cell layer ; It's the body part of a venous persistent thrombus .( aneurysm 、 Mural thrombus of ventricular aneurysm )

Naked eye : Rough 、 Dry cylindrical , Adhesion to vessel wall , Sometimes gray and reddish brown stripes can be seen ;

Light mirror : Platelet trabeculae are coral , There are many neutrophils on the surface , The fibers between the trabeculae form a network , The mesh contains a lot of red blood cells and a little white blood cells .

③ Red thrombus : With the prolongation of the mixed thrombus, it increases , Blocking the lumen , The blood flow downstream stops , It coagulates rapidly to form a red thrombus , The tail that makes up the persistent thrombus .

Naked eye : It's dark red , Fresh red thrombus moist , bouncy ; Old red clots are absorbed by water , Become dry and brittle , Lose elasticity , Easy to fall off , Cause thrombosis .

Light mirror : It's a lot of red blood cells , A small amount of cellulose and platelets dispersed in it can be seen .

④ Clear thrombus : It occurs in capillaries and small veins of microcirculation , It's mainly made of cellulose , Seen in disseminated intravascular coagulation .

embolism : Name explanation : Abnormal substances insoluble in blood appear in circulating blood , The phenomenon of blocking the lumen of blood vessels with blood flow .

type :① Thromboembolism -

1. Pulmonary embolism :

The source of embolization : Deep veins of the lower extremities , Especially the popliteal vein 、 Femoral vein and iliac vein .

The site and result of embolization :a. Small branches of the pulmonary artery : Generally, there are no symptoms , Collateral circulation compensation ; If there is pulmonary congestion before embolization , It can cause hemorrhagic infarction of lung tissue ; If small pulmonary embolism occurs for a long time , It can cause pulmonary hypertension 、 Right heart failure .

The color of the main pulmonary artery or the big sense , The patient has difficulty breathing 、 Cyanosis 、 Shock can lead to sudden death from acute respiratory and circulatory failure ;

The emboli are small but numerous , Can cause right heart failure ( Acute pulmonary heart disease ) And sudden death

2. Systemic arterial embolism :

The source of embolization : Mural thrombus in the left heart 、 Atherosclerotic ulcers and mural thrombi in aneurysms .

Location and results :a. The legs , The absence of effective collateral circulation can lead to local infarction ;b. Branches of coronary or cerebral arteries , Can be life-threatening .

② Fat embolism

The source of embolization : Comminuted fracture of long bone and severe trauma of adipose tissue 、 Burns release free fat droplets ; Diabetes, hyperlipidemia 、 Alcoholism and chronic pancreatitis .

Location and results : The diameter is greater than 20μm Into the right heart to the lungs , Cause pulmonary artery branches 、 Embolization of small arteries and capillaries ; The diameter is less than 20μm The branch from the left heart to the systemic circulation , Cause organ embolism , Such as cerebral vascular embolism , Cause brain edema, etc .

A small amount of fat is OK , A lot of it goes into the pulmonary circulation , Cause right heart failure and pulmonary edema , Cause difficulty in breathing .

③ Gas embolism

Air embolism :

The source of embolization : The outside air has broken veins into the blood , Like surgery 、 infusion 、 pneumothorax 、 Childbirth, etc .

Location and results : Air and blood mix into foam , Blood circulation disorders , Difficulty in breathing 、 Cyanosis ;

Nitrogen embolism ( Decompression and / or caisson disease ):

The source of embolization : The human body enters the normal pressure or low pressure environment from the high pressure environment , A large amount of gas dissolved in blood and tissue fluid is released rapidly , Nitrogen dissolves slowly in liquid , It leads to the formation of numerous small bubbles or the fusion of them into big bubbles in the study and organization , Forming a gas embolism .

Location and results :a. Muscles, tendons or ligaments , Cause muscle and joint pain ;

Heart, brain, lung and intestine , Ischemia and infarction ;

bone , Especially, the tibia, femur and humerus with more fat have ischemic necrosis , Spasmodic pain .

④ Other emboli P34


inflammation : Name explanation The defensive response of living tissues with vascular system to injury factors ;

Three basic pathological changes : Deterioration - The degeneration and necrosis of local tissue ;

exudation - The fluid and cellular components in the blood vessels of the local inflammatory tissue enter into the interstitial space through the vascular wall 、 The surface of body cavity mucosa or body surface ;

Physiological significance : Advantageous :(1) Diluting bacterial toxins ;(2) Bring complement antibody to the local area ;(3) Cellulose web formation :a. Stop the spread of bacteria ;b. Become a repair scaffold ; adverse : Oppression 、 Organized adhesion


The type of inflammation :P46/47 The full text reading

① Metaplasia : Acute severe hepatitis ( Hepatocyte poisoning ); Epidemic encephalitis B ( Nerve cells )

② Exudative inflammation :1. Serous inflammation : Blisters 、 Joint effusion 、 Catarrhal symptoms

2. Cellulitis : What happens in mucous membrane is called pseudomembranous inflammation , Such as swallowing diphtheria ; Serosa and mucous membrane

- Trachea, diphtheria 、 bacterial dysentery ; Cellulose in the pericardium

Inflammatory disease , The exudate of cellulose is pulled into villi as the heart beats

Attached to the surface of the pericardium , It's called fluffy heart ; Lung disease , Lobar

Pneumonia .

3. Suppurative inflammation : Name explanation - A lot of neutrophils exudate , And accompanied by varying degrees of tissue necrosis and pus formation of inflammation ;

Cellulitis - Diffuse suppurative inflammation in loose connective tissue , It's mostly caused by hemolytic streptococcus , It often occurs under the skin 、 muscle 、 The appendix . Pathological findings : There is diffuse infiltration of big neutrophils in the tissue , The boundaries with health organizations are not clear ;

Fester : Localized suppurative inflammation with abscess cavity formation , It's mainly caused by Staphylococcus aureus , It's mostly subcutaneous 、 Lung, brain and liver . Pathological findings : There is a large amount of cellulose network in the exudate of inflammatory area , Cause inflammation , The necrotic tissue in the inflammatory area liquefies to form pus , Reactive proliferation of surrounding granulation tissue forms abscess wall , It's a purulent cavity

Surface purulence and empyema : Mucosal and serosal surfaces ; Mucosal suppuration - Purulent catarrh 、 Purulent bronchitis 、 urethritis 、 Meningitis ;

Hemorrhagic inflammation : Bacterial infection ;, The inflammation is intense , A lot of red blood cells ooze out ( Plague 、 Epidemic bleeding )

③ Proliferative inflammation :1. Nonspecific proliferative inflammation ;2. Specific proliferative inflammation ;

The three phases of fever : A period of rising temperature ; High temperature duration ; Hypothermia period .

According to the initiation of shock :1. Hypovolemic shock ;2. Cardiogenic shock ;3. Angiogenic shock ;

The shock process : In the early : Less irrigation and less flow , Irrigation is less than irrigation ;

Shock stage : More irrigation and less flow , Irrigation is more than irrigation ;

Late stage of shock : No irrigation, no flow , Perfusion stopped ;

Microcirculation is the compensatory significance of changes in shock :1. Maintain arterial blood pressure ;2. Ensure the blood pressure supply of heart, brain and other important organs ;