instruction:
Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
question:
Abstract: Nucleated cells can resist lysis by and recover from complement attack even after formation of the potentially cytolytic membrane attack complex on the cell surface. We have found that human neutrophils resist complement lysis by the physical removal of membrane attack complexes by both endocytic and exocytic process. The latter mechanism predominates, vesiculation being detectable within 60 sec of initiating the complement cascade. Sixty-five percent of the formed complexes are removed on plasma membrane vesicles, although only 2% of the cell surface is lost. Ultrastructural examination revealed that these vesicles were covered with ring-like "classical" complement lesions. Analysis of these vesicles by gel electrophoresis indicated that C9 was present exclusively in the form of a sodium dodecyl sulfate-resistant, high m.w. complex. In contrast, the 35% of C9 that remained associated with the cells was found to be inaccessible to a C9-specific monoclonal antibody, and was partly degraded, suggesting internalization of the membrane attack complex and proteolysis of some C9 molecules. The molar ratio of C9 to C8 was 12 to 1 on shed vesicles and on recovered cells.
answer:
Cell Membrane

question:
Abstract: Despite the clear-cut result of the Australian Therapeutic Trial in Mild Hypertension, which demonstrated prospectively the benefit of treatment of diastolic blood pressure in the range of 95 to 109 mm Hg, a retrospective analysis that classified subjects by the average diastolic pressure level attained during the trial purported to show an absence of treatment benefit at lower average diastolic pressures and a negative treatment effect at higher levels. However, the method of classification by average attained diastolic pressure introduced substantial selection bias, invalidating the retrospective analysis and rendering as spurious both the deleterious treatment effect and its lack of efficacy at lower diastolic levels.
answer:
Australia

question:
Abstract: Hand injuries in children are seen frequently in the office and the emergency room. Basic principles determine which fractures, tendon injuries, dislocations, nerve injuries, fingertip injuries, infections, and amputations can be treated by the primary physician and which should be referred to a specialist.
answer:
Amputation, Traumatic