According to the ideal gas law, pressure varies linearly with temperature and quantity, and inversely with volume:

  
    
      
        p
        =
        
          
            
              n
              R
              T
            
            V
          
        
        ,
      
    
    {\displaystyle p={\frac {nRT}{V}},}
  where:

p is the absolute pressure of the gas,
n is the amount of substance,
T is the absolute temperature,
V is the volume,
R is the ideal gas constant.Real gases exhibit a more complex dependence on the variables of state. Vapour pressure
Vapour pressure is the pressure of a vapour in thermodynamic equilibrium with its condensed phases in a closed system.
Pineoblastoma is a malignant tumor of the pineal gland. A pineoblastoma is a supratentorial midline primitive neuroectodermal tumor.Pineoblastoma may occur in patients with hereditary uni- or bilateral retinoblastoma. When retinoblastoma patients present with pineoblastoma this is characterized as "trilateral retinoblastoma". Up to 5% of patients with hereditary retinoblastoma are at risk of developing trilateral retinoblastoma. Prognosis of patients with trilateral retinoblastoma is dismal, only a few patients have survived more than 5 years after diagnosis; all survivors were diagnosed with small tumors in a subclinical stage. Recent advances in (high-dose) chemotherapy treatment regimens and early detection have improved survival of patients with trilateral retinoblastoma to up to 50%. References


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