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61.
Tripeptide PGP in a dose of 1 mg/kg had a correcting effect on behavioral disorders in rats induced by stress exposure (forced swimming). PGP prevented the increase in anxiety and decrease in orientation and exploratory activity. Our results suggest that the effect of this peptide is realized via central nervous structures involved in organism’s response to stress factors. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 7, pp. 9–11, July, 2004  相似文献   
62.
It has been suggested for many years that the regulation of the immune system for the maintenance of peripheral tolerance may involve regulatory/suppressor T cells. In the past few years, several investigators have demonstrated that these cells can be generated in vitro. It has also been shown that they can inhibit the progression of various autoimmune disease models when infused into susceptible mice. We have generated two murine T cell lines in the presence of KLH-specific T cell clones from BALB/c or DBA2 mice. The lines are characterized by a low proliferative response to mitogens, the capacity to secrete high amounts of IL-10 and TGF-beta, and small amounts of IFN-gamma. Interestingly, these cells are unable to produce IL-2, IL-4 or IL-5. The study of the surface phenotype of both lines revealed CD4+, CD25high, CD44low and CTLA-4- cells. When injected intravenously in (CBy.D2) F1 mice, these cells were able to inhibit 50-100% of the TNP-specific antibody production, when the hapten was coupled to KLH. In the present study we offer another evidence for the existence of regulatory T cells in the T lymphocyte repertoire, suggesting that they can also regulate immune responses to foreign antigens. Furthermore, we demonstrate an alternative pathway to generate these cells different from approaches used thus far.  相似文献   
63.
CD4+CD25+调节性T细胞(Tr)是体内自然发生的调节性T细胞的重要亚群,具有无反应性和免疫抑制两大特性,主要通过与靶细胞的直接接触而起作用,其在体内不仅参与自身免疫性疾病、移植排斥反应等,还在肿瘤的发生、发展及免疫治疗中发挥重要作用.近几年来,Tr在肿瘤免疫中的作用倍受关注.  相似文献   
64.
65.
低收入大学生一般自我效能感、主观幸福感研究   总被引:31,自引:7,他引:31  
近年来 ,低收入大学生作为高校中的一个特殊群体逐渐受到研究者和教育者的关注。目前对低收入大学生的一般自我效能感 (generalself -efficacy)和主观幸福感的研究还不多见。一般自我效能感是指个体对各种挑战或新情境的应对能力的总体信心[1] 。一般自我效能感描述的是个体有效地应对各种紧张情境的广义而稳定的个人能力感 ,它与身心健康存在一定的关系[1- 2 ] 。主观幸福感 (subjectivewell-being)是指人们对于自己是否幸福的主观感受 ,是反应心理健康水平的重要指标之一。研究低收入大学生的一般自我效能感和幸福感的特点及其关系对于揭…  相似文献   
66.
Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture. Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells. The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut.  相似文献   
67.
BACKGROUND: Specific subgroups of people planning IVF might be at risk of having more psychological or health-related problems. Identification of subgroups at risk may better enable allocation of appropriate counselling. METHODS: A group of 425 men and 447 women planning to undergo IVF treatment filled out a questionnaire. Four domains of health-related quality of life were measured, namely perceived emotional, physical, cognitive and social functioning. RESULTS: Young men and women (aged 21-30 years) planning IVF had more short-term social and emotional problems than people of the same age group in the general population. No substantial differences were found in cognitive and physical functioning for all age groups of men nor women planning IVF compared with the general population. A high level of irrational parenthood cognitions substantially accounted for a less optimal score on all the different domains of quality of life. These cognitions ('needing a child in order to live a happy life') were especially prevalent among younger women. CONCLUSIONS: Patients with high levels of irrational parenthood cognitions are at risk of a less optimal quality of life. A short cognitive counselling therapy is advised for patients with high levels of these cognitions.  相似文献   
68.
One cDNA clone was purified from an adult Clonorchis sinensis cDNA library, and its deduced polypeptide sequence was found to be homologous with myosin regulatory light chain (MRLC) of invertebrates and vertebrates. Two amino-acid residues, Thr and Ser, were conserved at the phosphorylation sites that regulate the function of MRLCs. Recombinant C. sinensis MRLC (rCsMRLC) protein was produced and purified from Escherichia coli, and mouse anti-CsMRLC immune sera recognized a protein of molecular weight 24 kDa from a soluble protein preparation of C. sinensis. The CsMRLC protein was immunohistochemically localized to the muscle fibers of the subtegumental muscle layer and to the muscles of oral and ventral suckers. However, the rCsMRLC protein proved to be less useful antigen for the serodiagnosis of human clonorchiasis.The nucleotide sequence reported herein was submitted to GenBank and assigned accession number AY519356.  相似文献   
69.
70.
Summary Background: A link between violence and depression has been shown, but not a link between violence and postpartum depression. This study sought to determine if there is an association between a history of abuse (physical, sexual, emotional as a child or adult) and postpartum depression (PPD). Method: 200 postpartum women were recruited from 6 hospitals. At 8–10 weeks postpartum, a telephone interviewer asked women about physical, emotional or sexual abuse as an adult or child and sociodemographic, obstetrical and personal medical history. PPD was assessed using the Edinburgh Postnatal Depression Scale (EPDS, score of ≥12). Abuse was determined by the Conflict Tactics Scale or the Abuse Assessment Screen. Chi-square and logistic regression were used to determine the relationship between violence and PPD. Results: 11% of women had EPDS scores of ≥12. Rates of childhood (6.5%), or adult (6.5%) physical abuse; and childhood (13%) or adult (14%) sexual abuse were reported by respondents. Emotional abuse in the current relationship (29.6%) exceeded that of childhood abuse (3.5%). Overall 43.2% of respondents had at least one form of abuse. Having a history of depression (OR = 3.3 (95% CI, 1.3–8.7)), panic attack during pregnancy (OR = 5.4 (1.6–19.0)), maternal complications (OR = 5.0 (1.7–15.1)), low social support (OR = 3.3 (1.3–8.7)) and emotional abuse (OR = 2.8 (1.1–7.4) were associated with PPD. Conclusion: Emotional abuse but not physical or sexual abuse was found to be associated with PPD. A possible explanation for this relationship may be that being in an abusive situation puts one at risk for depression and in turn, postpartum depression.  相似文献   
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