Preksha Dhyana Human Body Part 2

Author(s): Jethalal S Zaveri
Publisher: Jain Vishva Bharati

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and fatigue after slight exertion are common symptoms. Later, breathing becomes more laboured. Silicosis and black lung are fibrosis of the lungs caused by inhalations of air laden with silicon dioxide or carbon particles in the mines.
Emphysema
Emphysema is one of the fastest growing diseases in the modern world. It is a disease of old age and results from the effects of smoking and air-pollution. In this disease, walls of the alveoli are atrophied and thinned; bronchioles are obstructed and total surface of the respiratory memberane is greatly reduced, sometimes to less than one quarter of the normal value. The capillary bed around the alveoli is also reduced. All these changes are irreversible and lead to increasing dysnea. The disease progresses over many years and the chronic straining to draw breath produces a barrel shaped chest and distended lungs.
Lung Cancer
The result of smoking that has most captured the public imagination is the development of carcinoma of the lung or lung cancer. This is a neoplastic growth, malignant and often fatal, which is more than 20 times as prevalent in smokers. As the malignant cells multiply, they suffocate the normal cells and destroy tissue. Removal of affected segments or of an entire lung by surgery is often resorted to as treatment.
Tuberculosis (T.B.)
Tuberculosis is sometimes called consumption. About half of us become infected with this disease at one time or another, but when the general health is good, the body's defences can usually contain the invading pathogens called tubercuse bacilli. They invade the lungs and the infected area becomes walled off by fibrous tissue forming "tubercle". Sometimes the bacilli spread producing tubercles in various sites.
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