Clinical Research Directory

Inclusion Criteria: * Age: 18-75 years old; Healthy volunteers: males weighing ≥50 kg, females weighing ≥45 kg, with a body mass index (BMI = weight (kg)/height² (m²)) within the range of 19.0-28.0 kg/m² (including boundary values); Cognitive disorders diagnosed clinically according to guidelines include Alzheimer's disease (AD) and mild cognitive impairment (MCI). Diagnostic criteria are as follows: 1) Clinical manifestations include symptoms such as memory impairment, difficulty concentrating, slowed thinking, and poor language skills; 2) Neuropsychological tests show that functions such as memory, attention, thinking, and language are below the normal population level; 3) Blood or cerebrospinal fluid tests show elevated levels of human β-amyloid 1-42, human β-amyloid 1-40, and human phosphorylated tau protein. 4) Exclusion of other factors that may cause cognitive impairment, such as drug or substance abuse, environmental factors, etc.; Signing an informed consent form for PET/MR or PET/CT examinations and voluntarily participating in this study. Exclusion Criteria: * Minors, pregnant women, breastfeeding women, individuals with severe liver or kidney dysfunction, and those with a history of allergy to contrast agents or other medications; Diagnosed with viral encephalitis, acute myelitis, idiopathic epilepsy, or antibody-negative AIE; Diagnosed with any major illness; history of alcohol or drug abuse/dependence; History of cardiovascular disease, tumours, blood disorders, or poorly controlled chronic conditions; Contraindications for PET/MR imaging. History of head trauma or surgery; History of other neurological disorders.