First year of using logbook. You must keep a logbook during this income year. Using the car for less than 12 weeks before the end of the income year. You are able to continue to keep the logbook in the following income year so that your logbook covers the required 12 weeks. Keeping logbooks for two or more cars. The logbook for each car must cover the same period.
Natural killer cell: A cell that can react against and destroy another cell without prior sensitization to it. Abbreviated NK cell. NK cells are part of our first line of defense against cancer cells and virus-infected cells. NK cells are small lymphocytes that originate in the bone marrow and develop without the influence of the thymus. An NK cell attaches to a target cell, releases chemicals that breach its cell wall, and causes it to lyse (break up).
Lymphocytes are much more common in the lymphatic system, and include natural killer T-cells. The blood has three types of lymphocytes: B cells, T cells and natural killer cells (NK cells). B cells make antibodies that bind to pathogens to enable their destruction. CD4+ (helper) T cells co-ordinate the immune response (they are what becomes defective in an HIV infection). CD8+ (cytotoxic) T cells and natural killer cells are able to kill cells of the body that are infected by a virus.