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91.
92.
IL-3对小鼠骨髓来源树突状细胞分化发育的影响 总被引:3,自引:0,他引:3
比较 GM- CSF IL- 4与 IL- 3 IL- 4两种方法培养制备的树突状细胞 (Dendritic cell,DC)在形态、产量、免疫表型和抗原摄取能力方面的差异。用 GM- CSF IL- 4和 IL- 3 IL- 4分别诱导小鼠骨髓来源的前体细胞分化为成熟树突状细胞 ,通过相差显微镜、扫描电镜、激光共聚焦扫描显微镜进行形态观察 ,流式细胞术分析细胞免疫表型和摄取抗原能力。结果表明 ,IL- 3 IL- 4诱导的 DC产量高 ,细胞纯度好 ,形态上与 GM- CSF IL- 4诱导的DC类似 ;细胞免疫表型显示高表达 MHC 类分子 ,但低表达或不表达 CD80、CD86 ;IL- 3 IL- 4诱导的 DC具有强大的摄取抗原能力。 IL- 3替代 GM- CSF可诱导低表达共刺激分子的耐受型 DC 相似文献
93.
患者男,5 5岁。因“发现右上腹包块5年,疼痛30d”于2 0 0 2年12月2 4日入院。查体:腹平软,右肋下约10cm处可扪及一包块,无压痛及反跳痛,肝肾区无叩痛,肠鸣音正常。于2 0 0 2年12月30日行右侧腹壁肿瘤切除术,术中见右侧腹壁有一约15cm×10cm×12cm大小灰红色肿物,累及腹膜浅层及肌层,部分区域与大网膜粘连,肿瘤未侵及皮下,压迫右肝前叶,余腹内脏器无异常。肿瘤质硬,边界尚清楚,肿物切面质脆,呈鱼肉状,中央部分坏死。病理检查:灰白灰红色组织1个,大小为15cm×10cm×8cm ,表面有一层纤维包膜,切面淡黄色,鱼肉状,部分区域呈黏液样,可见一8cm×6c… 相似文献
94.
95.
S. Cruchaga D'Harcourt A. Buño Soto V. Cascante Burgos D. Lozano Calero R. Martínez-Zapico 《European journal of clinical microbiology & infectious diseases》1996,15(9):749-752
To evaluate enzyme immunoassay (EIA) as an alternative to indirect immunofluorescence assay (IFA) to screen for Q fever in humans, 157 serum samples from patients suspected of having the disease were tested for immunoglobulin G antibodies toCoxiella burnetii. The agreement between the tests and the sensitivity of EIA were excellent (96.8% and 98.4%, respectively) when an IFAtiter of > 1/160 was considered positive. All serum samples with a titer of > 1/320 in the IFA were also positive by the EIA. The EIA seems to be an acceptable alternative to IFA for screening for Q fever. 相似文献
96.
Anti-inflammation Effects of Corn Silk in a Rat Model of Carrageenin-Induced Pleurisy 总被引:2,自引:0,他引:2
Pleurisy is an inflammation of the pleural layers that surround the lungs. Despite much research into inflammatory diseases,
no drugs with favorable safety profiles are available yet for their treatment. Corn silk has been used in many parts of the
world for the treatment of edema, cystitis, gout, kidney stones nephritis, and prostitutes. However, no scientific reports
on the anti-inflammatory effects of corn silk were so far available. To test the anti-inflammatory efficacy of corn silk extract
(CSEX) in a rat model of carrageenin (Cg)-induced pleurisy, exudate formation, and cellular infiltration, tumor necrosis factor
alpha (TNF-α), interleukin 1 beta (IL-1β), vascular endothelial growth factor alpha (VEGF-α), interleukin-17 (IL-17), C3 and
C4 complement protein levels, adhesion molecule (ICAM-1) and inducible nitric oxide synthase (iNOS) levels, nuclear factor
kappa B (NF-κB) activation, and total antioxidant activity were studied, respectively. Pretreatment with CSEX reduced Cg-induced
pleurisy exudate, number of leukocytes, oxidative stress, C3 protein level, and O2− levels at the inflammatory site. Pretreatment with CSEX also inhibited TNF-α, IL-1β, VEGF-α, and IL-17A and blocked inflammation-related
events (ICAM-1 and iNOS) by activation of NF-κB. Supplementation with CSEX may be a promising treatment for inflammatory diseases
that involve oxidative stress. 相似文献
97.
Zhang W Li H Bu H Chen H Tong H Liu D Guo H Lin SZ 《International journal of molecular medicine》2012,29(2):159-164
The aim of this study was to characterize the effects of emodin on dendritic cells (DCs) and CD4?CD25? regulatory T cells (Tregs). Myeloid DCs were prepared from peripheral blood mononuclear cells of healthy human donors and treated with emodin at different concentrations. The phenotype and T cell stimulatory capacity of these DCs were analyzed. The expression ratios of CD80 and CD83 in DCs in the presence of emodin (100 μg/ml) were significantly decreased compared with that in DCs without emodin treatment (P<0.05). IL-12p70 production of DCs decreased significantly with emodin treatment (P<0.05). Furthermore, an approximately 2-fold decrease was observed in the ability of DCs pre-treated with emodin to induce T-lymphocyte proliferation. In addition, we found that emodin treatment increased the number of Tregs, which expressed lower levels of human leukocyte antigen (HLA-DR), glucocorticoid-induced tumor necrosis factor receptor (GITR), and cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) as compared to cells without emodin treatment. Our results suggest that emodin inhibits the differentiation and maturation of DCs and induces Tregs, which may be helpful for the modulation of the immune rejection after liver transplantation. 相似文献
98.
目的探讨大学生人格变化与所处年级的关系。方法采用卡特尔人格问卷(16PF)对浙江农林大学健康管理专业大一至大三104名学生进行为期一学年前后测评。结果①具有统计学显著性变异的人格因子一年级有:C(t=2.079,P<0.05)、E(t=-3.606,P<0.01)、G(t=-2.456,P<0.05)、L(t=-4.86,P<0.01)、Q3(t=2.447,P<0.05)、Q4(t=-2.893,P<0.01);二年级有:E(t=-3.438,P<0.01)、I(t=3.369,P<0.01)、X3(t=-3.747,P<0.01)、Y2(t=-2.5277,P<0.05);三年级有:E((t=-2.832,P<0.01)、M(t=-3.092,P<0.01)、Q1(t=-2.361,P<0.05)、X4(t=-4.629,P<0.01)、Y2(t=-2.603,P<0.05);②不同年级相比,变异程度大的人格因子主要有C(t=-2.103,P<0.05)、I(t=2.321,P<0.05)、X1(t=2.25,P<0.05)、X3(t=-2.052,P<0.05);Q4(t=2.081,P<0.05)、X4(t=-2.322~-2.143,P<0.05)。结论大学生人格变异具有年级特点,一年级人格因子值提高的有C、Q3;降低的有E、G、L、Q4;二年级提高的有I,降低的有E、X3、Y2;三年级人格因子值降低的有E、M、Q1、X4、Y2。并且,情绪性因子变异程度较大。 相似文献
99.
Ai AL Peterson C Tice TN Huang B Rodgers W Bolling SF 《Journal of health psychology》2007,12(4):580-596
To address the inconsistent findings and based on Hegel's dialectic contradictive principle, this study tested a parallel mediation model that may underlie the association of using prayer for coping with cardiac surgery outcomes. Three sequential interviews were conducted with 310 patients who underwent open-heart surgery. A structural equation model demonstrated that optimism mediated the favorable effect of prayer coping. Prayer coping was also related to preoperative stress symptoms, which had a counterbalance effect on outcomes. Age was associated with better preoperative mental health, but age-related chronic conditions were associated with poor outcomes; both of these were mediated through the same mediators. 相似文献
100.
ABSTRACT: BACKGROUND: Severe acute respiratory syndrome (SARS) is an emerging infectious disease caused by the novel coronavirus SARS-CoV. The T cell epitopes of the SARS CoV spike protein are well known, but no systematic evaluation of the functional and structural roles of each residue has been reported for these antigenic epitopes. Analysis of the functional importance of side-chains by mutational study may exaggerate the effect by imposing a structural disturbance or an unusual steric, electrostatic or hydrophobic interaction. RESULTS: We demonstrated that N50 could induce significant IFN-gamma response from SARS-CoV S DNA immunized mice splenocytes by the means of ELISA, ELISPOT and FACS. Moreover, S366-374 was predicted to be an optimal epitope by bioinformatics tools: ANN, SMM, ARB and BIMAS, and confirmed by IFN-gamma response induced by a series of S358-374-derived peptides. Furthermore, each of S366-374 was replaced by alanine (A), lysine (K) or aspartic acid (D), respectively. ANN was used to estimate the binding affinity of single S366-374 mutants to H-2 Kd. Y367 and L374 were predicated to possess the most important role in peptide binding. Additionally, these one residue mutated peptides were synthesized, and IFN-gamma production induced by G368, V369, A371, T372 and K373 mutated S366-374 were decreased obviously. CONCLUSIONS: We demonstrated that S366-374 is an optimal H-2 Kd CTL epitope in the SARS CoV S protein. Moreover, Y367, S370, and L374 are anchors in the epitope, while C366, G368, V369, A371, T372, and K373 may directly interact with TCR on the surface of CD8-T cells. 相似文献