99 lines
5.7 KiB
Plaintext
99 lines
5.7 KiB
Plaintext
ÜÜÜÜÜÜÜÜÜÜÜÜÜ ÜÜÜ ÜÜÜÜ
|
|
ÜÛÛÛÛÛÛÛÛßÛßßßßßÛÛÜ ÜÜßßßßÜÜÜÜ ÜÛÜ ÜÛÛÛÛÛÛÛÛÜÜÜÜÜÛßß ßÛÛ
|
|
ßÛÛÛÛÛÛÛÛÛÛÛÛÛÛÜ ßÛÛ ÜÛÛÛÜÛÛÜÜÜ ßÛÛÛÛÜ ßÛÛÛÛÛÛÛÜÛÛÜÜÜÛÛÝ Ûß
|
|
ßßßÛÛÛÛÛÛÛÛÛÛÜ ÞÝ ÛÛÛÛÛÛÛÛÛÛÛßßÛÜÞÛÛÛ ÛÛÛÛÛÜ ßßÛÛÛÞß
|
|
Mo.iMP ÜÛÛÜ ßÛÛÛÛÛÛÛÝÛ ÞÛÛÛÛÛÛÛÛÛ ÞÛÛÛÛ ÞÛÛÛÛÛÝ ßÛß
|
|
ÜÛÛÛÛÛÛÛ ÛÛÛÛÛÛÛÛÝ ÞÛÛÛÛÛÛÛÛÝ ÛÛÛ ÛÛÛÛÛÛ
|
|
ÜÛÛÛÛÛÛÛÝ ÞÛÛÛÛÛÛÛÛ ÞÛÛÛÛÛÛÛÛ ß ÞÛÛÛÛÛÛÜ ÜÛ
|
|
ÜÛÛÛÛÛÛÛÝ ÛÛÛÛÛÛÛÛ ÛÛÛÛÛÛÛÛÝ ÞÞÛÛÛÛÛÛÛÛÛß
|
|
ÜÛßÛÛÛÛÛÛ ÜÜ ÛÛÛÛÛÛÛÛÝ ÛÛÞÛÛÛÛÛÝ ÞÛÛÛÛÛÛßß
|
|
ÜÛßÛÛÛÛÛÛÜÛÛÛÛÜÞÛÛÛÛÛÛÛÛ ÞÛ ßÛÛÛÛÛ Ü ÛÝÛÛÛÛÛ Ü
|
|
ÜÛ ÞÛÛÛÛÛÛÛÛÛÛß ÛÛÛÛÛÛÛÛÛ ßÛÜ ßÛÛÛÜÜ ÜÜÛÛÛß ÞÛ ÞÛÛÛÝ ÜÜÛÛ
|
|
ÛÛ ÛÛÛÛÛÛÛÛß ÛÛÛÛÛÛÛÛÛÛÜ ßÛÜ ßßÛÛÛÛÛÛÛÛÛß ÜÜÜß ÛÛÛÛÜÜÜÜÜÜÜÛÛÛÛÛß
|
|
ßÛÜ ÜÛÛÛß ßÛÛÛÛÛÛÛÛÛÛÜ ßßÜÜ ßßÜÛÛßß ßÛÛÜ ßßßÛßÛÛÛÛÛÛÛßß
|
|
ßßßßß ßßÛÛß ßßßßß ßßßßßßßßßßßßß
|
|
ARRoGANT CoURiERS WiTH ESSaYS
|
|
|
|
Grade Level: Type of Work Subject/Topic is on:
|
|
[ ]6-8 [ ]Class Notes [Essay on Benign Tumours ]
|
|
[ ]9-10 [ ]Cliff Notes [& Maligment Tumours ]
|
|
[x]11-12 [ ]Essay/Report [ ]
|
|
[ ]College [ ]Misc [ ]
|
|
|
|
Dizzed: 12/94 # of Words:666 School: ? State: ?
|
|
ÄÄÄÄÄÄÄÄÄ>ÄÄÄÄÄÄÄÄÄ>ÄÄÄÄÄÄÄÄÄ>Chop Here>ÄÄÄÄÄÄÄÄÄ>ÄÄÄÄÄÄÄÄÄ>ÄÄÄÄÄÄÄÄÄ>ÄÄÄÄÄÄÄÄÄ
|
|
TUMOURS
|
|
|
|
A tumour is a mass of new tissue growth that does not react to
|
|
normal controls or the organizing influence of other tissues, and it has no
|
|
useful function in the body. This applies to both types of tumours,
|
|
malignant and benign. Malignant, also known as, cancerous tumours, are
|
|
additionally defined by their invasion of local tissue and their ability to
|
|
spread to other parts of the body.
|
|
|
|
Benign Tumours
|
|
|
|
A benign tumour which is not cancerous, is less serious than
|
|
malignant tumours because they do not spread to other parts of the body,
|
|
but they may cause damage by local growth and pressure on other structures,
|
|
producing serious complications such as bleeding. Benign tumours generally
|
|
grow slowly and kill the host only if it occupies or attaches to an organ
|
|
so as to interfere with a critical function. The cells of benign tumours
|
|
closely resemble the cells of the tissue of origin. Surface benign tumours
|
|
include warts and moles.
|
|
|
|
Malignant Tumours
|
|
|
|
A malignant tumour always kills (unless treated) because of its
|
|
invasive and metastatic characteristics. The tumour grows locally by
|
|
spreading into surrounding tissues. Solid tumours, which develop in the
|
|
breast, colon, lung, and other organs, contain an inner core with high
|
|
pressure zones that compress and collapse blood vessels, often preventing
|
|
the penetration of blood-borne cancer treatments. It spreads to distant
|
|
sites by the breaking off of malignant cells, which move through the blood
|
|
and lymphatic systems, attach themselves, and begin to grow as new
|
|
colonies. Malignant tumours are diagnosed by examination of their
|
|
vascularity, shapes, forms of cells division, and differentiation. More
|
|
than a hundred different types have been identified in humans. In general,
|
|
those derived from epithelial tissue are carcinomas, and those from
|
|
connective tissue are sarcomas.
|
|
|
|
The most common form of malignant tumour of the respiratory tract
|
|
is lung cancer, which began increasing in frequency at an alarming rate
|
|
about 1940. In 1980 it was the leading cause of cancer deaths in men and
|
|
is also rapidly increasing in woman. It is attributed to cigarette smoking
|
|
and environmental pollution: cancer of the lung is rare in nonsmokers, and
|
|
exposure to materials such as asbestos, chromium, and radioactive
|
|
substances increases the probability of developing lung cancer.
|
|
|
|
Malignant tumours, also known as lymphomas, one of the main types
|
|
of lung cancer, arise in the lymph nodes related to the lungs and other
|
|
body tissue. the other main type of lung cancer is Sarcomas, it may
|
|
originate in the lungs or in some other structure such as a bone. Sarcomas
|
|
have a poor prognosis, but recent advances in the treatment of lymphomas
|
|
have increased the long term survival.
|
|
|
|
The factors controlling tumour growth are poorly understood,
|
|
although genetics seems to play a role Tumours in laboratory animals may
|
|
be transplanted to a second host using only a single tumour cell. This
|
|
suggests that only one normal cell needs to become cancerous for tumour
|
|
growth to begin. Tumours have been experimentally induced in animals by
|
|
chemical, physical, and viral agents, and by radiation.
|
|
|
|
Cancer researchers no longer believe that a single drug will be
|
|
able to cure cancer. Experts now believe that a combination of drugs will
|
|
be the best method to kill tumours. One route being researched utilizes
|
|
antibodies that bind to specific receptors on the tumour cell, thereby
|
|
inhibiting tumour growth by blocking certain tumour-growth factors from
|
|
entering the cell. Tumour necrosis factor (TFN), an immune-system protein,
|
|
has been found effective in cutting off the blood supply to tumours,
|
|
although too much TFN causes severe side effects.
|
|
|
|
The work of physician Francis Peyton Rous, gave rise to the virus
|
|
theory of the causes of cancer. In 1960, Rous found that he could transmit
|
|
a cancerous tumour (sarcoma) from one hen to another by using an injection
|
|
of tumour filtrate. The sarcoma virus was the first tumour virus
|
|
identified, and it opened up a whole new area of cancer research. Rous
|
|
shared the 1966 Nobel Prize for physiology or medicine for his work.
|
|
|