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Non-Hodgkin lymphoma of the testis   总被引:2,自引:0,他引:2  
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A technique for simultaneous bilateral biplane arteriography of the abdomen, pelvis, and lower extremities is described. The biplane views provided clinically significant information in approximately 40% of cases.  相似文献   
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The specificity of T-cell helper factor in man   总被引:7,自引:3,他引:4       下载免费PDF全文
Supernates of human T cells stimulated with TT antigen contain a factor that induces mitogenesis and immunoglobulin synthesis in autologous as well as allogeneic B cells. A fraction of the IgG produced has specificity against TT. The T-cell-derived LMF-TT eluted after albumin on Sephadex G 200 and did not contain immunoglobulin heavy chain determinants. LMF-TT was active on B cells from TT immune as well as TT- nonimmune individuals but in the latter instance the IgG secreted had no specificity against TT. B cells incubated with LMF-TT in the presence of a second antigen (DT) made IgG with specifity to that antigen provided the B-cell donor was immune to that second antigen. LMF-TT-containing supernates were depleted of TT antigen by Sephadex G 200 chromatography followed by passage over anti-TT immunosorbent columns. The antigen-free supernates were able to induce mitogenesis and IgG synthesis in B cells but the IgG produced failed to exhibit specificity against TT unless the TT antigen was readded to the B-cell cultures. The optimal concentration of LMF-TT (50 percent) inducing B-cell mitogenesis was different from the optimal concentration (20 percent) causing IgG synthesis by B cells. At low LMF concentrations (less than or equal 10 percent) addition of a second antigen to which the cell donor was immune caused an increase in the degree of B-cell mitogenesis. Submitogenic concentrations of LMF-TT (less than or equal to 5 percent) were still capable of inducingimmunoglobulin synthesis in B cells At these low concentrations of LMF-TT the proportion of anti-TT IgG over total IgG increased sharply. B cells from TT immune donors were separated on TT immunosorbent columns. Cells that bound to the column were more sensitive to the mitogenic and IgG synthetic effects of LMF-TT than unfractionated B cells. Thus, LMF is a nonspecific human T-cell helper factor which behaves like a polyclonal B-cell activator. However, in the presence of specific antigen (TT) the antigen-specific B cell is preferentially triggered by LMF. The experimental design of the present study does not rule out the additional presence of an antigen-specific helper factor in the supernates of TT-stimulated human T cells.  相似文献   
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Death is present in the daily reality of nurses who work with children in ICU. This research aimed to comprehend nurses' experience while taking care of children and his/her family experiencing the death process. Symbolic Interactionism was adopted as a theoretical reference framework, while Interpretative Interactionism was used as a methodological reference framework to analyze the biographical narratives of seven nurses who took part in the research. The events that determined the nurses' history in this context were: FACING THE DEATH OF THE CHILD, PROJECTING YOURSELF IN THE MOTHER'S ROLE and PROMOTING FAREWELL. The analyzed data made it possible to understand the nurses' experience in care for children and their families during the death process.  相似文献   
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