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891.
892.
Apollo Pronk Piet Leguit Arthur A. G. M. Hoynck van Papendrecht Edwin Hagelen Theo J. M. V. van Vroonhoven Henri A. Verbrugh 《In vitro cellular & developmental biology. Animal》1993,29(2):127-134
Summary Normal human mesothelial cells (NHMC) were isolated from pieces of human omentum. The cell yield was approximately one million
cells per square centimeter omentum. The mesothelial cells were identified by their positive staining with monoclonal antibodies
against cytokeratins 6 and 18. Transmission electronmicroscopy of cultured NHMC revealed many microvilli on the apical surface
and many mitochondria and pinocytotic vesicles in the cytoplasm, indicating active transmembrane transport. Growth of NHMC
was directly related to the concentration of human serum or of fetal bovine serum in the growth medium. Addition of epidermal
growth factor with or without hydrocortisone resulted in a significant increase of NHMC growth; when endothelial cell growth
factor, insulin, or hydrocortisone were added no such increase was observed. Seeding NHMC at densities less than 3000/cm2 did not result in monolayer formation. The mesothelial cells were serially passed in growth medium M199 with added 10% fetal
bovine serum up to 7 passages. However, after Passage 4 the cells changed into giant cells with an irregular pattern, and
a lack of intracellular cytokeratin expression was observed for most of the cells. 相似文献
893.
894.
Individuals of many species differ consistently in their behavioralreaction to mild novel challenges. Suites of these behaviorsare referred to as behavioral syndromes or personalities. Personalitytraits are often phenotypically and genetically correlated.Therefore, animal personalities are generally considered asbroad characteristics, with one underlying genetical and physiologicalmechanism that is expressed across situations and contexts.Because there are carryover effects between situations, animalsare not entirely flexible in their behavior in each situation.This may cause behaviors to seem nonadaptive in isolated situations.To test whether individuals with different personalities couldreact differently to changes in their environment, we studiedcontext dependence of personalities in the great tit (Parusmajor). We tested birds categorized as either fast or slow explorersfor their latency to come back to a feeding table after a mildstartle (risk-taking behavior) in a nonsocial followed by asocial context. We found that the relation between exploratorybehavior and risk-taking behavior depended on the social context.Females in general returned later in the social test, whilemale reaction to the presence of a conspecific was dependenton their behavioral type. Slow males thereby reacted to thebehavior of the companion and fast males did not. These resultsshow that although personalities have a rigid structure therelation between personality traits is context dependent. Theseresults are discussed in the perspective of the adaptive significanceand maintenance of personalities. 相似文献
895.
Reviews in Environmental Science and Bio/Technology - 相似文献