public void SetValuesInDoctorSpecialtyComboBoxForAppointmentSearch()
        {
            DoctorService       doctorService        = new DoctorService();
            List <SpecialtyDTO> allDoctorSpecialties = doctorService.GetAllSpecialties();

            AppointmentDoctorSpecializationComboBox.ItemsSource = allDoctorSpecialties;
        }