Research "recover from illness defense complex" helper T cell immune mechanisms based on the "Fuxie" theory clearing away heat evil thoroughly nourishing kidney treatment of recurrent blood-heat syndrome Psoriasis

INTERVENTION: Healthy control group:No intervention;Treatment Group:Modified cooling Xiaofeng powder;Control Group:Avium A capsule; CONDITION: Psoriasis vulgaris PRIMARY OUTCOME: Detection and screening of downstream cytokines(IFN‐?\IL‐4\IL‐17A\IL‐17F\IL‐22\TGF‐ß\IL‐10 \IL‐ 9);Itching degree score;The quantities and distribution of Th1, Th2, Th17, Treg, Th22 and Th9 cells in peripheral blood;Genes and proteins levels of transcription factors(T‐bet\GATA3\ROR?t\Foxp3);Psoriasis area and severity index; INCLUSION CRITERIA: Patients INCLUSION CRITERIA: 1.Complies with the diagnostic criteria for psoriasis vulgaris in dermatovenerology 8th Edition; 2. Complies with the diagnostic criteria for blood‐heat syndrome in Guidelines for the Clinical Research of Chinese Medicine New Drugs and New Dermatology of Traditional Chinese Medicine; 3. Aged 18 to 70 years; 4. Patients signed informed consent; 5. Recurrent psoriasis patients must belong to the types of recurrenceIV, V, VI. Health volunteers INCLUSION CRITERIA: 1. Aged 18 to 65 years; 2. No family history of psoriasis; 3. People who used corticosteroids or immune agents within a month. 4. People without serious systemic diseases, tumors, immunodeficiency or mental disorders.