Recurrent respiratory infections are often associated with B cell deficiencies, leading to inadequate antibody production.

Streptococcus pyogenes is the most common cause of pharyngitis and is detected by rapid strep tests.

Escherichia coli is the most common cause of urinary tract infections.

SLE is characterized by a humoral immune response, particularly the production of autoantibodies.

The cavitary lesion in the right upper lobe is characteristic of pulmonary tuberculosis, which is caused by Mycobacterium tuberculosis.

Granulomas in the lymph nodes are characteristic of tuberculosis, which is caused by Mycobacterium tuberculosis.

The MMR vaccine (measles, mumps, rubella) is effective in preventing measles.

The measles vaccine provides active immunity by stimulating the immune system to produce antibodies.

To find the original concentration, multiply the number of colonies by the dilution factor: 1,200 colonies * 100 = 120,000 CFU/mL.

Post-exposure prophylaxis for hepatitis B includes administering the hepatitis B vaccine.

An 80% reduction means that 20% of the original viral load remains. 20% of 5,000 copies/mL is 1,000 copies/mL.

Allergic reactions are primarily mediated by humoral immunity, specifically IgE antibodies.

If 25% of the bacteria are resistant, then 75% are susceptible to the antibiotic.

The meningococcal vaccine is the most effective preventive measure against Neisseria meningitidis infection.

Clostridium difficile is known for causing antibiotic-associated diarrhea and produces toxins that lead to severe gastrointestinal symptoms.

Oral thrush in an immunocompromised patient is most commonly caused by Candida albicans.

Yellow fever virus is endemic in tropical regions and can cause fever, jaundice, and abdominal pain.

HIV primarily targets and destroys CD4+ helper T cells, leading to immunodeficiency.

Items should be exposed to ethylene oxide gas for at least 8 hours for effective sterilization.

The primary immune response usually peaks around 10-14 days after the initial exposure to an antigen.

Humans have five different classes of antibodies: IgA, IgD, IgE, IgG, and IgM.

Sterilization at 160°C dry heat typically requires 60 minutes of exposure.

If the contact time is 10 minutes, it can be used 6 times in an hour.

In 3 hours (180 minutes), there are 6 doubling periods (180/30). Starting from 1 bacterium, after 6 doublings, there will be 2^6 = 64 bacteria.

The ID50 is the dose required to infect 50% of the population. Therefore, 500 organisms are needed to infect 50% of the population.

A reduction of 99.9% means that 0.1% of the original load remains. 0.1% of 1,000,000 CFU/mL is 1,000 CFU/mL.

The dilution factor is 1:10, as the concentration is reduced by a factor of 10.

At 134°C, the sterilization time can be reduced to approximately 20 minutes due to the increased temperature.

With a 90% success rate, 10% will remain unprotected. 10% of 500 is 50 individuals.

Septic shock is primarily driven by the innate immune response, which leads to systemic inflammation and shock.