The process that cells and their tissues and organs can survive under the stimulation of various harmful factors in the internal and external environment is called adaptation. Morphological manifestations are atrophy, hypertrophy, proliferation and metaplasia.
1. atrophy: refers to the reduction of the volume of parenchymal cells, tissues and organs that have developed normally.
1. Physiological atrophy: Many tissues and organs of the human body naturally undergo physiological atrophy with age.
2. Pathological atrophy:
(1) Malnutrition atrophy: It can be divided into local malnutrition atrophy and systemic malnutrition atrophy, and the latter is hunger and malignant tumor cachexia.
(2) Compressive atrophy: for example, renal atrophy caused by hydronephrosis.
(3) disuse atrophy: that is, atrophy caused by long-term workload reduction.
(4) Nerve atrophy: for example, muscle atrophy caused by nerve injury.
(5) Endocrine atrophy: for example, adrenal atrophy caused by pituitary adenoma.
2. Hypertrophy: the increase in the volume of cells, tissues and organs.
1, compensatory hypertrophy: cell hypertrophy has the significance of functional compensation.
2, endocrine hypertrophy: hormone-induced hypertrophy is called endocrine hypertrophy.
Hyperplasia: the increase of parenchymal cells can lead to the increase of tissues and organs.
1, physiological hyperplasia: hyperplasia under physiological conditions.
2. Pathological hyperplasia: hyperplasia in pathological state.
Metaplasia: the process of transforming a differentiated and mature cell into another cell.
1, epithelium: gastric gland epithelium → intestinal metaplasia
Columnar epithelium (trachea, cervix, gallbladder) → squamous metaplasia
2. Interstitial: fibrous connective tissue → bone and cartilage
Skeletal muscle → skeleton
Cell and tissue damage in the second quarter
I. Causes and mechanisms
Second, morphological changes.
(1) Degeneration: refers to some reversible morphological changes caused by metabolic disorder after cell or interstitial injury. The abnormal substance or normal substance in cytoplasm or stroma is abnormally increased.
1, cell edema: the increase of intracellular water.
Naked eye: the organs are swollen and pale.
Microscopically, according to the severity of the lesion, it showed granular degeneration, loose degeneration and balloon degeneration respectively.
2. Fatty degeneration: the accumulation of triglycerides in cells.
(1) The most common sites: liver cells, myocardial fibers and renal tubular epithelium.
(2) Pathological changes: fatty liver degeneration (severe fatty liver)
Myocardial steatosis → tiger-spotted heart
3. Vitreous transformation: also known as hyalinization.