It is an essential substance for human growth and development, especially for fetuses and infants. It participates in calcium and phosphorus metabolism, promotes their absorption, and plays an important role in bone formation.

It plays an important role in the formation of human bones, reconstruction of bone tissue, muscle contraction, nerve transmission, coagulation mechanism and maintaining capillary permeability.

This product is the dried bacteria of brewer's yeast, which is rich in B vitamins and has an auxiliary therapeutic effect on indigestion.

This drug belongs to Class 2A, i.e., a β1-receptor blocker without partial agonist activity (cardioselective β-receptor blocker). It has a selective blocking effect on β1-receptors, no PAA (partial agonist activity), and no membrane stabilizing effect. Its effect on blocking β-receptors is approximately equal to that of propranolol (PP), and its selectivity for β1-receptors is slightly inferior to that of atenolol. Metoprolol's effects on the heart, such as slowing heart rate, inhibiting cardiac contractility, reducing automaticity, and delaying atrioventricular conduction time, are similar to those of propranolol and atenolol (AT). Its effect on reducing elevated blood pressure and heart rate during exercise testing is also similar to that of PP and AT. Its contraction effect on vascular and bronchial smooth muscle is weaker than that of PP, so its effect on the respiratory tract is also smaller, but still stronger than that of AT. Metoprolol can also reduce plasma renin activity.

This product is a fluoroquinolone antibacterial drug with a broad-spectrum antibacterial effect, especially high antibacterial activity against aerobic Gram-negative bacteria. It has good antibacterial activity against the following bacteria in vitro: most bacteria of the Enterobacteriaceae family, including Citrobacter, Enterobacter cloacae, Enterobacter aerogenes and other Enterobacter species, Escherichia coli, Klebsiella, Proteus, Salmonella, Shigella, Vibrio, Yersinia, etc. Norfloxacin also has antibacterial activity against multi-drug resistant bacteria in vitro. It also has good antibacterial effects on penicillin-resistant Neisseria gonorrhoeae, Haemophilus influenzae and Moraxella catarrhalis. Norfloxacin is a bactericide that acts on the A subunit of bacterial DNA helicase, inhibiting DNA synthesis and replication, leading to bacterial death.

This product has a broad-spectrum antibacterial effect and has antibacterial activity against most Enterobacteriaceae, Gram-positive bacteria, Mycoplasma pneumoniae, Chlamydia pneumoniae, etc., but has poor effects on anaerobic bacteria and enterococci. Its mechanism of action is to inhibit the activity of bacterial DNA gyrase, prevent the synthesis and replication of bacterial DNA, and cause bacterial death.