private void comboBox6_SelectedIndexChanged(object sender, EventArgs e)
        {
            comboBox7.Items.Clear();
            if (System.IO.File.Exists("horariosatencion.xml"))
            {
                XmlReader reader = XmlReader.Create("horariosatencion.xml");
                while (reader.Read())
                {
                    if (string.Compare(reader.Name, "rutmedico") == 0)
                    {
                        reader.Read();

                        if (string.Compare(reader.Value, comboBox5.SelectedItem.ToString()) == 0)
                        {
                            reader.Read();
                            reader.Read();
                            if (string.Compare(reader.Name, "fecha") == 0)
                            {
                                reader.Read();
                                if (string.Compare(reader.Value, comboBox6.SelectedItem.ToString()) == 0)
                                {
                                    reader.Read();
                                    reader.Read();

                                    while (reader.Read())
                                    {
                                        if (string.Compare(reader.Name, "hora") == 0)
                                        {
                                            reader.Read();
                                            comboBox7.Items.Add(reader.Value);
                                            reader.Read();
                                        }
                                    }
                                }

                            }
                        }


                    }
                }
                reader.Close();
            }
        }