Flashcards in MOD Deck (186)
How does the cns 'regenerate'
Origional tissue not restored but plasticity allows for new pathways to form.
Why might the cns not regenerate?
It may disrupt memory formation
Give examples of physiological and pathological hyperplasia
Physiological - endometrial proliferation,
Pathological - goitre, eczema
Give some physiological and pathological examples of hypertrophy
Phys - muscle bulk
Pth - cardiac hypertrophy, prostatic hypertrophy
At what point does atrophy become irreversable?
When a large number of functional cells are lost
Give some examples of atrophy
Thin skin in pvd
How does metaplasia occur.
One differentiated cell type replaced from stem cells by another of the same germ layer
What is a neoplasm?
An abnormal growth of cells that persists after the initial stimulus is removed
What is a malignant neoplasm?
A neoplasm that invades surrounding tissues and has the potential to spread to distant sites
What is a tumour?
A clinically detectable lump or swelling
What is cancer?
A malignant neoplasm
What is dysplasia?
Disordered but reversible cell organisation. Pre neoplastic
How do benign neoplasms appear macroscopically?
A growing mass with a smooth capsule of compressed tissues
What are macroscopic features of malignant neoplasm?
Infiltration of surrounding tissues, irregular outer margin, ulceration, necrosis
What are microscopic features of benign and malignant neoplasms?
Progression from highly differentiated cells to poorly differentiated. More likely to be malignant if poorly differentiated.
What cellular cells can be seen in malignant neoplasms?
Increased nucleus size
Pleomorphism (variation in cell size and shape)
When are cellular changes very important in malignacy diagnosis?
On a needle biopsy.
What makes the majority of ca. Risk? Interinsic or extrinsic factors?
What is the initiator promotor model of cancer?
Initiators are mutagens that result in a primary mutation. Promotors then cause replication of the cell creating many monoclonal copies.
What is the evidence that neoplasms are monoclonal?
In a female (xx) look at 2 isoenzymes for g6p dehydroginase (x linked) some cells produce one, some the other. Stain. All neoplasms create just one isoenzyme.
What are malignant epilthilial neoplasms called?
What are malignant mesenchymal neoplasms called?
What is a leukemia?
A malignacy of blood forming bone marrow
What is a malignancy of lymph nodes?
What is a germ cell neoplasm?
A malignancy of pluripotent cells
What is a blastoma?
A neoplasm of imature precusor cells
What is a tumour of smooth muscle?
What is a glioma?
A benign tumour of glial cells
What is a malignant neoplasm of glial cells?