Located in Kamijōjō, Kai City, Yamanashi Prefecture, Ōkubo Clinic is an internal medicine clinic offering English language services, parking facilities, and barrier-free accessibility. Situated approximately a 5-minute drive from JR Ryūō Station, this clinic provides consultations on a first-come, first-served basis, with its medical services primarily focused on internal medicine. In general internal medicine, the clinic addresses a wide range of symptoms and conditions including colds, tonsillitis, fever, fatigue and lethargy, weight loss, dizziness upon standing, loss of appetite, hay fever, hives, diabetes, lifestyle-related diseases, and stroke. In pediatrics, in addition to treating children's fever, colds, diarrhea, loss of appetite, and allergic symptoms, the clinic also administers vaccinations. Furthermore, the clinic handles gastrointestinal disorders, treating diseases of the esophagus, stomach, duodenum, liver, gallbladder, bile duct, pancreas, and large intestine. For patients with fever and cold symptoms, consultations are generally conducted by car, and examinations proceed in order among those with reservations. Closed days include Thursdays, Sundays, and holidays, as well as January 1st to 3rd, August 13th to 16th, and December 29th to 31st. The clinic maintains close medical collaboration with multiple healthcare institutions including Yamanashi Prefectural Central Hospital, University of Yamanashi Hospital, JCHO Yamanashi Hospital, National Kōfu Hospital, Kōfu Kyōritsu Hospital, Kōfu Neurosurgical Hospital, and Tokyo Medical University Hospital, enabling timely referrals when hospitalization or detailed examinations are necessary.