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101.
A solid-phase enzyme immunoassay using both mouse monoclonal and goat polyclonal antibodies against carcinoembryonic antigen (CEA) was developed. The assay detects 0.6 to 1.2 ng of CEA per ml of serum and has 3 incubation steps which can be performed in 1 day. Polystyrene balls coated with polyclonal goat anti-CEA antibodies are first incubated with heat-extracted serum samples. Bound CEA is then detected by addition of mouse monoclonal antibodies, followed by goat IgG anti-mouse IgG1 coupled to alkaline phosphatase. Results with this enzyme immunoassay using monoclonal antibodiies (M-EIA) have been compared with those obtained by the conventional inhibition radioimmunoassay (RIA) using goat antiserum. Three hundred and eighty serum samples from 167 patients with malignant or non-malignant diseases and from 134 normal individuals with or without heavy smoking habits were analyzed by the 2 assays. Excellent correlation between the results of the 2 assays was obtained, but the M-EIA, using monoclonal antibodies from a single hybridoma, did not discriminate better than the conventional RIA between CEA produced by different types of carcinoma and between CEA associated with malignant or non-malignant diseases. Follow-up studies of several patients by sequential CEA determinations with the 2 assays showed that the M-EIA was as accurate as the RIA for the detection of tumor recurrences.  相似文献   
102.
IgG4-related disease is a recently established systemic condition. Tubulointerstitial nephritis is the most common renal manifestation. Glomerular lesions, particularly membranous glomerulonephritis, can develop simultaneously. Some patients present with serological renal dysfunction associated with elevated IgG or IgE levels and hypocomplementemia, while others are incidentally found to have abnormalities in kidneys on imaging. A majority of patients with IgG4-related kidney disease have similar lesions at other anatomical sites, which help us to suspect this condition. Serum IgG4 elevation (>135 mg/dL) is the most, although not entirely, specific marker for the diagnosis. Imaging findings varies from small nodules to bilateral diffuse abnormalities. In addition to the renal parenchyma, the renal pelvis and perirenal adipose tissue can be affected. Histological features include dense lymphoplasmacytic infiltration, storiform or “bird’s eye” fibrosis (highlighted by PAM stain), and IgG4-positive plasma cell infiltration (>10 cells/high-power field and IgG4/IgG-positive cell ratio >40%). Immune complex deposition is detectable in the tubular basement membrane by immunofluorescence and/or electron microscopy. Patients usually respond well to corticosteroids, but highly active diseases may require other immunosuppressive therapies. Further investigations will be required to fully understand pathophysiology underlying this emerging condition.  相似文献   
103.
背景:随着生物人工肝在临床上的应用,需要有一种方便、有效、实用的保护生物反应器装载细胞活力及功能的方法,设计有自主知识产权的生物人工肝用肝细胞的低温保护液迫在眉梢。 目的:验证海藻糖作为低温保护剂在4 ℃低温保存肝细胞的作用。 方法:采用C3A人永生化肝细胞系在不同低温保存液(DMEM培养液,乳酸钠林格氏液,加有不同浓度海藻糖的乳酸钠林格氏液,UW液)4 ℃保存24,48,72 h。复苏后行细胞活力、细胞损伤指标、氧自由基代谢相关指标等检测,并通过荧光双染法观察细胞凋亡情况。 结果与结论:不同低温保存液保存不同时间C3A细胞的活力、细胞损伤及细胞凋亡表现均有所不同,其中同时间点不同浓度海藻糖组均优于单用乳酸钠林格氏液组,但不如UW液组(P < 0.01)。而保存24 h的不同浓度海藻糖组及UW液组与乳酸钠林格氏液组相比差异无显著性意义(P > 0.05),提示海藻糖能有效减轻低温对肝细胞凋亡及缺血再灌注损伤的程度,可成为低温保存液中有效及重要的保护剂组分。  相似文献   
104.
BACKGROUND: Bacterial signals play an important role in the maturation of the immune system. Polymorphisms in genes coding for receptors to bacterial components can alter the immune responsiveness of the host to microbial agents and may indicate the development of aberrant immune responses that are associated with immune-mediated diseases such as atopic diseases. OBJECTIVE: The study's objective was to investigate the relationship between TLR4 and CD14 gene polymorphisms, the LPS responsiveness of PBMCs, and the presence of asthma and allergic rhinoconjunctivitis in children. METHODS: The TLR4 (Asp299Gly) and CD14/-159 polymorphisms were determined in 115 Swedish children aged 8 and 14 years. LPS-induced IL-12(p70), IL-10, and IFN-gamma responses of PBMCs from 69 of the children were analyzed by means of ELISA. The levels of soluble CD14 in serum samples were analyzed by means of ELISA, and the total IgE levels were analyzed by means of UniCAP Total IgE (Pharmacia Diagnostics, Uppsala, Sweden). RESULTS: Decreased LPS-induced IL-12(p70) and IL-10 responses were associated with the TLR4 (Asp299Gly) polymorphism and independently with asthma, especially atopic asthma. The TLR4 (Asp299Gly) polymorphism was associated with a 4-fold higher prevalence of asthma in school-aged children (adjusted odds ratio 4.5, 95% CI 1.1-17.4) but not to allergic rhinoconjunctivitis. CONCLUSION: A TLR4 polymorphism modifies innate immune responses in children and may be an important determinant for the development of asthma. This may influence the outcome of intervention studies that use microbial stimuli as immune modulators.  相似文献   
105.
运动训练对心力衰竭患者血浆肿瘤坏死因子的影响   总被引:4,自引:0,他引:4  
目的 观察CHF患者血浆肿瘤坏死因子和受体水平的变化及适量步行运动对其的影响,并探讨适量步行运动对慢性心力衰竭患者的治疗价值。方法 将142例心功能Ⅱ、Ⅲ级的(2H17患者随机分为运动组(常规+运动,86例)和对照组(常规,56例)。运动治疗方法:运动组入组后,上、下午各1次,每次6 min适量步行运动,总疗程8w;对照组仅在入组时和治疗8w结束时进行适量步行运动。两组均在入组前后和治疗8w后同时采集肘静脉血2ml测定血浆TNF-α及STNFR的水平。结果 142例心功能Ⅱ、Ⅲ级的CHF患者在入组后进行限定的运动时间和运动量后发现,运动后较运动前血浆TNF-α及STNFR水平均显著升高(P<0.01),而治疗8w后两组血浆TNF-α及STNFR水平均明显下降(P<0.05);治疗期间运动组较对照组血浆TNF-α及STNFR水平下降明显(P<0.05);治疗8w后运动组的运动距离较对照组增加更明显(P<0.05)。结论 每天适量的步行运动可以有效降低CHF患者血浆炎性细胞因子的含量,有利于CHF患者的康复。  相似文献   
106.
实时荧光PCR研究新进展   总被引:6,自引:1,他引:6  
  相似文献   
107.
目的 :trans- (± ) - 3,4 - dichloro- N- methyl- N - [2 - (1- pyrrolidinyl) cyclohexyl]- benzeneacetam ide (U 5 0 4 88H)是κ阿片受体的选择性激动剂。实验观察静脉注射 U 5 0 4 88H (10 mg/ kg) 2 4 h后对心脏的延迟性保护作用及其细胞内机制。方法 :1采用离体灌流的大鼠心脏模型 ,通过局部缺血 /再灌注 ,以心脏梗死面积作为心脏损伤的判定标准 ,观察 U 5 0 4 88H预处理 (U P)对心脏的延迟性保护作用。 2采用分离的大鼠心肌细胞模型 ,通过代谢抑制(metabolic inhibition,MI) ,观察 UP对心肌细胞内静息 Ca2 + 和电诱导 Ca2 + 瞬变的影响。结果 :1U P可显著降低心脏梗死面积 ;2 U P的大鼠心肌细胞在 MI时 ,心肌细胞内静息 Ca2 + 的升高程度较对照组显著降低 ;3U P的大鼠心肌细胞在 MI时 ,心肌细胞电诱导 Ca2 + 瞬变的降低程度较对照组显著减少。上述作用均可被 U P前 10 min腹腔注射κ阿片受体的选择性阻断剂 nor- binaltorphim ine (10 m g/ kg)阻断。结论 ::U 5 0 4 88H可通过刺激κ阿片受体产生延迟性的心脏保护作用 ,此作用与心肌细胞内的 Ca2 + 稳态的调节有关。  相似文献   
108.
The CD40/gp39 pathway is known to be an important feature of B/T cell collaboration leading to T cell-dependent activation, proliferation or differentiation of B cells. Additionally, CD40 is involved in the regulation of B cell survival and apoptosis. Recently, CD40 has been shown to be expressed functionally on non-hematopoietic cells, i.e. endothelial cells. Here, we demonstrate that human keratinocytes (KC) cultured in vitro express CD40 constitutively. The surface expression of CD40 is markedly up-regulated following stimulation with interferon (IFN)-γ, but not with tumor necrosis factor-α or interleukin (IL)-1β. This process is regulated at the CD40 mRNA level as demonstrated by Northern blot analysis. Furthermore, ligation of CD40 via soluble gp39, the CD40 ligand, enhances intercellular adhesion molecule (ICAM)-1 and Bcl-x up-regulation on IFN-γ-stimulated KC, but not lymphocyte function-associated antigen (LFA)-3, B7-2, HLA-DR, or Fas expression. The release of IL-8 is also induced following CD40 ligation on KC. In psoriasis, a T cell-mediated inflammatory skin disease, KC have a markedly enhanced expression of CD40. This expression co-localizes with the expression of ICAM-1, Bcl-x, and an influx of CD3+ T cells. These findings suggest a functional role of CD40 on KC in inflammatory skin disorders such as psoriasis and could make a therapeutic intervention by disrupting the CD40/gp39 pathway an approach to consider in these inflammatory skin diseases.  相似文献   
109.
110.
The present study evaluated the effect of various surface treatments for zirconia ceramics on shear bond strength between an indirect composite material and zirconia ceramics. In addition, we investigated the durability of shear bond strength by using artificial aging (20,000 thermocycles). A total of 176 Katana zirconia disks were randomly divided into eight groups according to surface treatment, as follows: group CON (as-milled); group GRD (wet-ground with 600-grit silicon carbide abrasive paper); groups 0.05, 0.1, 0.2, 0.4, and 0.6 MPa (airborne-particle abrasion at 0.05, 0.1, 0.2, 0.4, and 0.6 MPa, respectively); and group HF (9.5% hydrofluoric acid etching). Shear bond strength was measured at 0 thermocycles in half the specimens after 24-h immersion. The remaining specimens were subjected to 20,000 thermocycles before shear bond strength testing. Among the eight groups, the 0.1, 0.2, 0.4, and 0.6 MPa airborne-particle abraded groups had significantly higher bond strengths before and after thermocycling. The Mann-Whitney U-test revealed no significant difference in shear bond strength between 0 and 20,000 thermocycles, except in the 0.2 MPa group (P = 0.013). From the results of this study, use of airborne-particle abrasion at a pressure of 0.1 MPa or higher increases initial and durable bond strength between an indirect composite material and zirconia ceramics.  相似文献   
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