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71.
Sam68 has been initially described as a substrate of src kinases during mitosis in fibroblasts. Recent evidence suggests that in T lymphocytes Sam68 may act as an adaptor protein and participate in the early biochemical cascade triggered after CD3 stimulation. A direct interaction between Sam68 and the two src kinases involved in T cell activation, p59fyn and p56lck, as well as a partnership of Sam68 with various key downstream signaling molecules, like phospholipase Cγ-1 and Grb2, has been shown. In this study we analyze the contribution of p56lck, as well as the role of ZAP-70, the second class of protein tyrosine kinase involved in T cell activation, in Sam68 tyrosine phosphorylation in the human Jurkat T cell line. Using the src inhibitor PP1 [4-amino-5-(4-methylphenyl)7-(t-butyl) pyrazolo [3,4-d] pyrymidine] and cell variants with defective expression of p56lck or expressing a dominant negative form of ZAP-70, we demonstrate that, while both p56lck and ZAP-70 are dispensable for the low constitutive phosphorylation of Sam68 observed in Jurkat cells, a cooperation between the two kinases is required to increase its rapid phosphorylation observed in vivo after CD3 stimulation. We also show that recombinant forms of both p56lck and ZAP-70 phosphorylate Sam68 in vitro. However, using CD2 stimulated cells, we observe that p56lck activation by itself does not induce Sam68 tyrosine phosphorylation. We conclude that p59lck and p56lck differently participate in regulating the phosphorylation state of Sam68 in T cells and that ZAP-70 may contribute to Sam68 tyrosine phosphorylation and to the specific recruitment of this molecule after CD3 stimulation.  相似文献   
72.
Predominance of Ehrlichia ewingii in Missouri dogs   总被引:3,自引:0,他引:3       下载免费PDF全文
To investigate the species distribution of Ehrlichia present in Missouri dogs, we tested 78 dogs suspected of having acute ehrlichiosis and 10 healthy dogs. Blood from each dog was screened with a broad-range 16S rRNA gene PCR assay that detects known pathogenic species of Ehrlichia and ANAPLASMA: The species was determined by using species-specific PCR assays and nucleotide sequencing. Ehrlichia antibody testing was performed by using an indirect immunofluorescence assay with Ehrlichia chaffeensis as the antigenic substrate. The broad-range assay detected Ehrlichia or Anaplasma DNA in 20 (26%) of the symptomatic dogs and 2 (20%) of the asymptomatic dogs. E. ewingii accounted for 20 (91%), and E. chaffeensis accounted for 1 (5%) of the positives. Anaplasma phagocytophilum DNA was detected in one dog, and the sequences of regions of the 16S rRNA gene and the groESL operon amplified from the blood of this dog matched the published sequences of this organism. Antibodies reactive with E. chaffeensis were detected in 14 (67%) of the 21 PCR-positive dogs and in 12 (19%) of the 64 PCR-negative dogs. Combining the results of PCR and serology indicated that 33 (39%) of 85 evaluable dogs had evidence of past or current Ehrlichia infection. We conclude that E. ewingii is the predominant etiologic agent of canine ehrlichiosis in the areas of Missouri included in this survey. E. canis, a widely recognized agent of canine ehrlichiosis, was not detected in any animal. The finding of E. ewingii in asymptomatic dogs suggests that dogs could be a reservoir for this Ehrlichia species.  相似文献   
73.
A series of substances (designated CTQ compounds) with a guanidine group have been synthesized and tested for their ability to promote neuronal survival and neurite outgrowth. Mouse neuroblastoma clonal cell lines grown in serum-containing medium for 10 days as well as primary cultures of embryonic chicken ganglion neurons grown in serum-free defined medium for 1 or 2 days have been used for the experiments. Among the various CTQ compounds (CTQ1–CTQ20) tested, only CTQ8 exerted positive neurotrophic effects on these peripheral neuronal cells. At a concentration of 10−4 M, CTQ8 enhanced neuritogenesis of neuroblastoma cells. However, the most striking influence of CTQ8 was its promoting effect (6- to 10-fold) on the survival of chicken ciliary and dorsal root ganglionic neurons at concentrations ranging from 10−3 M to 5×10−4 M.  相似文献   
74.
The lipoxygenase product hydroperoxyeicosatetraenoic acid (HPETE) has immunosuppressive properties in vitro and in vivo. It was observed that 15-HPETE inhibit the sheep red blood cell rosette formation and the concanavalin A-induced blast transformation of human lymphocytes. This inhibition was HLA-linked. HLA-B12 subjects were less sensitive than non-B12 subjects. It is likely that HPETE acids are macrophage mediators which inhibit some lymphocyte functions.  相似文献   
75.
BackgroundSelf-management is critical to optimizing the health of individuals with a chronic condition or disability and is, therefore, a central concept in individual and family-centered healthcare delivery. The purpose of this review is to report the state of the science of self-management for individuals with spina bifida (SB) from a lifespan perspective.ObjectiveThis review will summarize the (a) development and use of self-management skills and behaviors across the life span, (b) factors related to self-management behaviors, (c) development of generic or condition-specific measures of self-management used with a spina bifida population, and (d) development and/or outcomes of interventions to improve self-management in SB.MethodsThe search strategy was limited to primary research articles published between 2003 and 2019 and followed PRISMA guidelines. The databases searched included: PubMed, CINAHL, PsycINFO, Web of Science, Cochrane, and Google Scholar. Studies that addressed self-management concepts in individuals throughout the life span and published in English were included.ResultsThe search yielded 108 citations and 56 articles met inclusion/exclusion criteria. A systematic narrative synthesis was reported. The level of evidence identified was primarily Level III articles of good quality. Multiple demographic, environmental, condition and process factors were related to self-management behaviors. SB self-management instruments and intervention development and testing studies were identified.ConclusionsThis review provides a synthesis of the state of the science of self-management including factors related to self-management behaviors, preliminary evidence of instruments for use in SB, factors important to consider in the development and testing of future interventions, and gaps in the literature.  相似文献   
76.
Medicine, Health Care and Philosophy - As individuals grow older, they usually require assistance with the daily tasks of self-care. This type of assistance, ancillary care, is essential to...  相似文献   
77.
Journal of Occupational Rehabilitation - Purpose This study aimed to understand age differences in wage-replacement duration by focusing on variations in the relationship across different periods...  相似文献   
78.
79.

The Fast Friends Procedure (FFP) is a widely used experimental paradigm to induce emotional intimacy. Besides exploring the validity of a German translation of the paradigm (n?=?46), we developed an extension of the FFP that induces sexual intimacy and assessed heart rate, high-frequency heart rate variability, and electrodermal activity responses to the FFP and its extension. Furthermore, we examined its applicability to individuals with childhood maltreatment (n?=?56), who frequently suffer from intimacy-related difficulties. Intimacy, positive affect, liking, and attraction increased during the FFP and partly during the sexual intimacy extension in both study groups. Moreover, both groups showed physiological responses consistent with positive social interactions. The use of the German FFP and its sexual intimacy extension can thus be recommended for research in the general population and in individuals with childhood maltreatment, although more studies are needed to further validate the paradigms.

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80.
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