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Anti-inflammatory activity and protective effect against CCl (4)-induced hepatotoxicity of alcoholic extract of leaves of WITHANIA SOMNIFERA have been assessed. The leaves were found to possess marked effects in subacute inflammation and hepatotoxicity. A comparison of the anti-inflammatory properties revealed the extract at 1 g/kg dose to be as active as 50 mg/kg of phenylbutazone and 10 mg/kg of hydrocortisone. The protective effect of the extract at 1 g/kg dose against CCl (4)-induced hepatotoxicity was comparable to 10 mg/kg of hydrocortisone.  相似文献   
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Milieu relationships provide the critical background presence to staff's attempts to motivate, regulate, and teach patients how to cope with stress. Forging a connection with hospitalized children and adolescents demands attention to how they respond to adults and engage with staff around milieu expectations. Assessment guides that deal with these issues are presented. Important aspects of children's relatedness are presented in the context of their working models of adults and the influence of these representations on their response to staff. Coping skills are explained with particular emphasis on behavioral coping strategies. Tied to the assessment process are interventions that emphasize staff's role in helping patients manage strong affects and avoid the use of nonproductive behavior regulation strategies.  相似文献   
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This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts.  相似文献   
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Summary: Aging is associated with progressive decline in immune functions and increased frequency of infections, autoimmunity, and cancer. Among immune functions, a decline in T‐cell functions during aging predominates. In this review, I discuss the molecular signaling of three distinct pathways of apoptosis, namely the death receptor pathway, the mitochondrial pathway, and the most recently described endoplasmic reticulum stress pathway, and the relative sensitivity of naïve, central memory, and effector memory CD8+ T‐cell subsets to apoptosis. In addition, I review apoptosis, especially via death receptor pathway, in naïve and various memory subsets of CD4+ and CD8+ T cells (with primary emphasis on CD8+ naïve and memory subsets) in human aging and discuss the role of apoptosis in immune senescence.  相似文献   
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Follistatin and activin A production by the male reproductive tract   总被引:1,自引:0,他引:1  
Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.   相似文献   
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