25（OH）-D is a prehormone that is produced in the liver by hydroxylation of vitamin D3 (cholecalciferol) by the enzyme cholecalciferol 25-hydroxylase. Physicians worldwide measure this metabolite to determine a patient's vitamin D status.
Ferr is a universal intracellular protein that stores iron and releases it in a controlled fashion. The protein is produced by almost all living organisms, including algae, bacteria, higher plants, and animals. In humans, it acts as a buffer against iron deficiency and iron overload. Ferritin is found in most tissues as a cytosolic protein, but small amounts are secreted into the serum functioning as an iron carrier. Plasma ferritin is also an indirect marker of the total amount of iron stored in the body. Hence serum ferritin is used as a diagnostic test for iron-deficiency anemia.
Hepatitis C is a liver disease caused by the hepatitis C virus (HCV): the virus can cause both acute and chronic hepatitis, ranging in severity from a mild illness lasting a few weeks to a serious, lifelong illness. Hepatitis C is a major cause of liver cancer.
HBsAg is the surface antigen of the hepatitis B virus (HBV). It indicates current hepatitis B infection. Biotime HBsAg Rapid Quantitative Test kit can detect the specimen of serum and plasma.
Human pepsinogens I (PGI) and II (PGII) are proenzymes of pepsin—an endoproteinase of gastric juice. PGI is secreted mainly by chief cells in the fundic mucosa, whereas PGII is also secreted by the pyloric glands and the proximal duodenal mucosa. Serum PGI and PGII concentrations and the ratio between PGI and PGII may be related to the histologic and functional status of the gastric mucosa.
Human Pepsinogens are aspartic proteases produced in the gastric mucosa and secreted into the gastric lumen that play a major role in the digestion of proteins after activation of acidic pH. It is synthesized as isoymogens and is classified into two groups (Pepsinogen I and Pepsinogen II).
Human Pepsinogens are aspartic proteases produced in the gastric mucosa and secreted into the gastric lumen that play a major role in the digestion of proteins after activation of acidic pH. It is synthesized as isoymogens and is classified into two groups (Pepsinogen I and Pepsinogen II).
PSA, a protein produced by prostate gland cells, circulates through the body in two ways: either bound to other proteins or on its own. PSA traveling alone is called free PSA. The free-PSA test measures the percentage of unbound PSA.
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