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441.
This study focuses on patterns of communication and interaction for peer support, which develop among parents of screen-positive children in the socio-medical space created by the diagnostic uncertainty of newborn screening, the limitations of established patient support groups and the daily challenges of screen-positive care management. Based on semi-structured interviews conducted in 2015–2017 with 34 Israeli parents whose child is screen positive, we describe and analyze the spontaneous grouping of parents using the WhatsApp instant messaging service for smartphones. These self-help groups did not reflect an attempt to forge an alternative movement of de-medicalization but rather to provide satisfactory answers to shared problems of care management under diagnostic uncertainty. These self-help groups are further discussed as a form of biosociality and lay expertise where elements of communication such as simplicity, reciprocity, and deliberative democracy serve as a complementary mirror-image of the asymmetrical patient–doctor communication.  相似文献   
442.
Summary Plasma membranes, generated in vivo by actively growing YAC lymphoma cells, were isolated from cell-free ascites fluid of lymphoma-bearing mice. Partial purification of the ascites fluid (AF) by means of ultracentrifugation resulted in the identification of two main fractions: (a) membrane fragments (AFM s ) and (b) membrane vesicles (AFM p ). Electron microscopy studies, polyacrylamide gel electrophoresis, marker enzymes, and binding capacity of radioactive lectins, have indicated that these membranes are released from the cell surface of YAC lymphoma cells, presumably by a shedding-off mechanism.In vitro studies have demonstrated that the isolated membranes can specifically inhibit the association of normal macrophages and YAC lymphoma cells. In vivo studies have shown that these membranes can immunize against YAC tumors if injected intramuscularly or subcutaneously into adult mice. The results indicate that the ascites fluid membranes bear tumor-specific antigenic determinants.Our results suggest that in vivo shedding of plasma membrane fragments or of membrane vesicles by actively growing YAC lymphoma cells may induce a self-protection of ascites tumors from host immune rejection.Abbreviations YAC= Moloney-virus-induced lymphoma cells grown in A-strain mice - AF= ascites fluid of YAC lymphoma-bearing mice - AFMs and AFMp= membrane fragments and vesicles isolated from AF - PBS= phosphate-buffered saline - Con A= Concanavalin A  相似文献   
443.
In most cooperatively breeding birds, individuals do not breed with their natal group members. In order to breed, they have either to disperse into another group or wait for an opposite-sex individual to join their group. In most of these species, females disperse more than males. We develop a dynamic game-theoretic model to account for this asymmetry. When males are physically larger/heavier than females, this allows them to effectively welcome female immigrants into their natal group and overcome the local females' opposition more than vice versa. The model further assumes that the dispersal decision is not confined to a restricted time window, but is rather based on acquired information and responsive to opportunities. The model predicts that (i) females disperse more than males, and (ii) females are willing to tolerate more risks in dispersal than do males. The latter prediction is supported inter alia by the fact that in many cooperatively breeding birds, females disperse at a younger age, and further away from their natal group as compared to dispersing males.  相似文献   
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