Myocarditis is caused by infectious (coxsackie A and B viruses, Chagas disease) andimmune causes. Clinically, the patient may be asymptomatic or may suffer from acute heart failure or even dilated cardiomyopathy.
Definitions The study of the essential nature of disease, including symptoms/signs, patho-genesis, complications, and morphologic consequences including structural and functional alterations in cells, tissues, and organs The study of all aspects of the disease process focusing on the pathogenesis leading to classical structural changes (gross and histopathology) and molecu-lar alterations The etiology (cause) of a disease may be genetic or environmental. The pathogen-esis of a disease defines the temporal sequence and the patterns of cellular injurythat lead to disease. Morphologic changes of the disease process include both gross changes and microscopic changes. The clinical significance of a disease relates to its signs and symptoms, disease course including complications, and prognosis. Methods Used Gross examination of organs on exam questions has 2 major components: identify-ing the organ and identifying the...
CARCINOGENESIS Carcinogenesis is a multistep process, and development of all human cancersappears to require the accumulation of multiple genetic changes. These changes can involve either inherited germline mutations or acquired mutations. Once a sin-gle severely mutated cell forms, monoclonal expansion of the cell’s line can cause a tumor. Most important mutations in tumorogenesis involve growth promoting genes (proto-oncogenes), growth inhibiting tumor suppressor genes, or the genes regulating apoptosis and senescence. Activation of growth promoting oncogenes. Proto-oncogenes are normal cellulargenes involved with growth and cellular differentiation. Oncogenes are derived from proto-oncogenes by either a change in the gene sequence, resulting in a new gene product (oncoprotein), or a loss of gene regulation resulting in overexpression of the normal gene product. Mechanisms of oncogene activation include point muta-tions, chromosomal translocations, gene amplification, and...
MALIGNANT NEOPLASMS Carcinoma of the breast is the most common cancer in women and affects 1 in 9 women in the United States. It is also the second most common cause of cancer death. The incidence is increasing and is higher in the United States than in Japan. Many risk factors have been identified. The incidence increases with the following factors: • Age • Unusually long/intense exposure to estrogens (long length of reproductive life, nulliparity, obesity, exogenous estrogens) • Presence of proliferative fibrocystic changes, especially atypical hyperplasia • First-degree relative with breast cancer Hereditary influences are thought to be involved in 5–10% of breast cancers, with important genes a...
Comments
Post a Comment