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101.
用EBV LMP2A重组痘苗病毒 (rVV LMP2A )转染人树突状细胞 (DC ) ,转染后的DC分别在第 1、 7、 14天刺激相同MHC背景的T细胞 ,在IL 2作用下诱导LMP2A特异性CTL。用LDH释放法检测CTL杀伤活性 ;流式细胞术 (FACS )检测CTL诱导分化过程中CD3+ 、CD4 + 、CD8+ 、CD5 6 + 等细胞的分群变化 ;RT PCR检测细胞分化过程中FasLmRNA表达 ;生物活性法检测功能性细胞因子IFN γ的分泌。结果显示本法诱导的CTL对靶细胞有特异性杀伤活性 ,第 2次和第 3次DC刺激后杀伤活性有所上升 ;在CTL诱导分化的第 7、 14、 2 1天细胞分群以CD4 + 、CD8+ 细胞为主 ;RT PCR证实所诱导的细胞内有FasLmRNA的表达 ;随细胞培养天数的增加IFN γ分泌增加 ,在第 14天达到较高水平。研究表明重组痘苗病毒载体rVV LMP2A转染的DC刺激T细胞可诱导出EBV LMP2A特异性CTL。  相似文献   
102.
Serum levels of circulating immune complexes (CIC) assayed by the Raji cell radioimmunoassay, total haemolytic complement (TCH50), Clq and C3 were correlated with clinical stage, histological type, age, sex and treatment of eighty-six children with Hodgkin's disease over a period of 4 years. Most significant findings were the changes of levels of CIC, TCH50, Clq and C3 during disease activity and following treatment. Significant perturbations were also seen in association with relapse. Levels of C and CIC were significantly elevated (P less than 0.001) at the time of diagnosis prior to splenectomy and/or any treatment. In the group before treatment, 81 percent of CIC levels were above 16 micrograms/ml with a maximum value of 1120 micrograms/ml. During treatment 33 percent were still above normal with a maximum of 320 micrograms/ml. Within 1 year after cessation of treatment, 37 percent also remained above normal levels with a maximum of 240 micrograms/ml. At relapse prior to treatment, 63 percent were again elevated with a maximum of 1280 micrograms/ml. The most significant difference on TCH50 levels relates to treatment periods. Sera of patients with active disease who are previously untreated show elevation of TCH50 levels (P less than 0.001) (average 127 CH50 mu/ml. During and after treatment eht TCH50 levels drop to 96 and 102 CH50 mu/ml, as compared to normal control of 100 CH50 mu/ml. In sera of patients at the first, second or third relapse, the combined TCH50 levels are significantly different from controls and across treatment periods (P less than 0.005).  相似文献   
103.
BACKGROUND AND OBJECTIVES: The use of the manual hexadimethrine bromide (polybrene) test in routine cross-matching after accurately detecting cell grouping and irregular antibodies is prevalent in China. This article reports the importance of serum protein mediums in the performance of the manual hexadimethrine bromide test. MATERIALS AND METHODS: Blood group O red blood cells and Blood group AB and Rh positive serum were collected at random from healthy blood donators, IgG anti-D serum separated from pregnant woman, then tested with each other by the manual hexadimethrine bromide methods in routine tests and some designed corresponding tests with IgG, IgM anti-D monoclonal diagnostic reagents and some serum protein components. RESULTS: Red blood cells that were adjusted to 3-5% suspension by normal saline then only added in 0.7 ml low ionic medium (LIM) and two drops of polybrene solution adhere to the surface of test tubes' bottom when centrifuged, so it was difficult to perform the next approach, but the adherence disappeared when red blood cells' concentrations exceeded 20-30%. Rh positive red blood cells coated by anti-D have the same phenomenon. This adherence can be prevented by serum medium diluted from 1:128 to 1:1024 times by normal saline and hemoglobin medium diluted from 1:32 to 1:128 times, but not by albumin or immunoglobulin medium. The denary logarithm values of the greatest inhibited dilutions of serum and hemoglobin elution between antibody sensitizing red blood cells and the same pre-sensitizing red blood cells tests were no significant difference (P value > 0.05). CONCLUSIONS: The whole serum or serum protein mediums are important factors that can influence successfully performance of the manual hexadimethrine bromide test. So appliance of the manual hexadimethrine bromide test to immunohematology laboratory, such as when performing titrations of serum or plasma, or when testing eluates for antibody activity, this adherence must be considered.  相似文献   
104.
The acceleration of nephritis in SNF(1) mice by CD4(+) T-cell clones reactive with a nephritogenic idiotype, Id(LN)F(1) [1], as well as the ability of anti-Id(LN)F(1) antisera to down-regulate the production of Id(LN)F(+)(1) immunoglobulin (Ig) in vivo and delay nephritis [2], suggests that dysregulation of this idiotype may contribute to the development of SNF(1) nephritis. Herein, we show that a monoclonal Id(LN)F(1)-expressing antibody, 540, significantly (P< or = 0.01) stimulated Id(LN)F(1)-reactive T-cell clones B6 and D2 to proliferate, while other Id(LN)F+1 antibodies did not. Further, injection of 540-producing hybridoma cells into nonautoimmune (SWRxBalb/c)F(1) mice resulted in the deposition of Id(LN)F(+)(1) Ig in the kidneys, in a pattern indicative of early nephritis. To identify the pathogenetic Id(LN)F(1) epitope(s) at the molecular level, we compared the deduced amino acid sequences of the heavy and light chain variable regions of pathogenetic and non-pathogenetic Id(LN)F(1)-expressing Igs 540, 317, and 533. Two overlapping peptides derived from the V(H) sequence of 540 (aa 54-66 and 62-73), which both contain the triple basic amino acid motif K(X)K(X)K, stimulated SNF(1) T cells and T-cell clones B6 and D2. These results further support the involvement of a subset of Id(LN)F(1)-expressing Ig in SNF(1) nephritis.  相似文献   
105.
In a community sample of 2,327 Caucasians, we tested the hypotheses that polymorphisms in the COMT and DRD3 genes are associated with personality traits conferring vulnerability to anxiety, depression, or alcohol misuse, or with current symptoms of these; and that the association is stronger in persons who also have been exposed to stressor experiences. To conserve resources and to allow replication, the genetic analysis was undertaken in two stages. For the COMT polymorphism, no statistically significant associations were found in the first sample of 862 persons. The remainder of the sample was therefore not analysed for that gene. For the DRD3 polymorphism, those in the first sample with at least one of the Ser(9) alleles had significantly higher scores in neuroticism (p=0.006) and behavioral inhibition (p=0.003). There was a trend, failing to meet the 1% significance criterion, for those with this genotype also to have higher depression and anxiety. The groups did not differ in alcohol use. In persons with the Ser(9) allele who were also exposed to stressors, there was a higher level of depression at the 5% level; and the depression level was higher in homozygotes. But when the remainder of the sample (1,465) was analysed, none of the associations reached statistical significance. We conclude that neither the COMT nor DRD3 polymorphisms are associated with anxiety, depression, or alcohol abuse. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:102-107, 2000 Copyright 2000 Wiley-Liss, Inc.  相似文献   
106.
Summary 1. In the alert, pigmented rabbit, eye movements were recorded during optokinetic nystagmus (OKN) and during optokinetic afternystagmus (OKAN). These responses were elicited by steps in surround-velocity ranging from 5–110°/s during binocular as well as monocular viewing. 2. In the baseline condition, OKN showed an approximately linear build-up of eye velocity to a steady-state, followed by a linear decay of eye velocity during OKAN after the lights were turned off. Build-up during binocular viewing was characterized by a constant, maximum eye-acceleration (about 1°/s2) for stimulus velocities up to 60°/s. OKAN, instead, was characterized by a fixed duration (about 10 s) for stimulus velocities up to 20°/s. Steady-state eye velocity saturated at about 50°/s. 3. Monocular stimulation in the preferred (nasal) direction elicited a build-up that was on average twice as slow as during binocular stimulation. Steady-state velocity during monocular stimulation saturated at about 20°/s. OKAN was of equal duration as during binocular stimulation. In the non-preferred direction, a very irregular nystagmus was elicited without velocity build-up. The stronger response to binocular stimulation, compared to the responses under monocular viewing condition in either nasal and temporal direction suggests potentiation of the signals of either eye during binocular viewing. 4. OKN and OKAN were re-assessed after intra-floccular microinjection of the nonselective cholinergic agonist carbachol. In the binocular viewing condition, eye-acceleration during build-up was strongly enhanced from 1°/s2 before to 2.5°/s2 after injection. The saturation level of steady-state eye velocity was also increased, from 50°/s before to more than 60°/s after carbachol. The duration of OKAN, however, was shortened from 10 s before to 6 s after injection. The response to monocular stimulation in the preferred direction revealed similar changes. 5. The flocculus appears to be involved in the control of the dynamics of OKN in the rabbit. Cholinergic mechanisms affect the floccular control of the rate at which slow-phase velocity can be built up and the rate of decay of eye velocity during OKAN. Cholinergic stimulation of the flocculus enhances the dynamics of OKN, while velocity storage is shortened.  相似文献   
107.
J A Cairns  G R Guy    Y H Tan 《Immunology》1992,75(4):669-673
In this study, we demonstrate that low but not high concentrations of interleukin-6 (IL-6) potentiate the cytotoxic effect of tumour necrosis factor-alpha (TNF-alpha) on U937 cells, in a dose-dependent manner. Killing of U937 cells by 100 U/ml of TNF-alpha, was maximally potentiated by 50 U/ml of IL-6. No potentiation of cell killing was observed when the concentration of IL-6 was increased to 4000 U/ml. At a concentration of 50 U/ml, IL-6 up-regulated TNF receptor expression but no change in TNF receptor number was observed when the concentration of IL-6 was increased to 4000 U/ml. Low concentrations of IL-6 can also induce sub-cytotoxic doses of TNF-alpha (0.1 and 0.33 U/ml) to kill U937 cells. Up-regulation of TNF receptors by IL-6 is dependent on de novo protein synthesis since receptor induction is abolished in the presence of cycloheximide. Taken together the data suggest that the potentiation of cell killing observed by a combination of these lymphokines is mediated in part by IL-6-induced changes in TNF receptor expression.  相似文献   
108.
Patients with severe group A streptococcal infections have abnormalities in the Vbeta repertoire of peripheral blood T cells that are consistent with superantigen stimulation by cytoplasmic membrane proteins. The purpose of this study was to determine whether similar changes in Vbeta repertoire could be found for patients with acute rheumatic fever (ARF). The mean Vbeta repertoire of peripheral blood T cells in nine hospitalized ARF patients was similar to that of 34 controls and did not change during 6 months of follow-up in 6 of the ARF subjects. We were unable to detect changes in the Vbeta repertoire of peripheral blood T cells from patients with ARF that could be attributed to the influence of a superantigen.  相似文献   
109.
The patient presented with the typical features of Down syndrome: hypotonia, brachycephaly, flattened occiput, bilateral prominent medical epican-thic folds, flat nasal bridge, protruding tongue, low-set dysplastic ears, short broad hands, bilateral clinodactyly and simian crease. The karyotype of this child was originally reported as normal. High-resolution chromosomes revealed extra material on the long arm of chromosome 18. The mother's karyotype showed a reciprocal translocation between the long arm of 18 and the long arm of 21 at band q23 and q22.1, respectively. FISH performed separately with two different 21q cosmid probes gave two signals on the mother's metaphases and three signals on the prob-and. These findings confirmed that the proband is trisomic for the long arm of chromosome 21 at loci D21S65 and D21S19.  相似文献   
110.
KOCH三角的解剖   总被引:6,自引:0,他引:6  
本实验解剖了110例人心标本(成人70、儿童40)的Koch三角区,观察和测量了房室结的形态、大小、毗邻和标志。房间隔及冠状窦口上、下方均有肌束连于房室结。Todaro腱在儿童多全部为腱性;在成人,其后部为肌性。三角区的深面为左、右心房壁和室间隔顶所构成的锥形间隙,其内为进入房室结区的血管和神经。根据构成不同,可将三角区分为5个区,即前上角的纤维支架区和房室结区,其余部分自上向下分别为房间隔区、右房壁区和室间隔区。本文还讨论了这些形态结构的功能及外科意义。  相似文献   
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