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101.
Thies A Schachner M Berger J Moll I Schulze HJ Brunner G Schumacher U 《The Journal of pathology》2004,203(4):933-939
Aberrant glycosylation is a common feature of metastatic sub-clones of malignant tumours and in uveal melanoma in particular, the HNK-1 glycotope has been positively correlated with poor prognosis. So far, no such correlation has been investigated in cutaneous melanoma. In order to do so, HNK-1 expression was evaluated immunohistochemically in 100 primary cutaneous melanomas and correlated with metastasis after up to 10-years' follow-up. Furthermore, HNK-1 expression was analysed in metastatic deposits (19 distant cutaneous metastases and six sentinel lymph node metastases), as well as in benign nevi. Kaplan-Meier analysis revealed a positive association between HNK-1 expression and metastasis (p < 0.005) and multivariate Cox regression analysis adjusted for the standard prognostic markers ulceration and vertical tumour thickness confirmed HNK-1 expression as an independent prognostic marker. HNK-1 expression was preserved in 42% of the distant cutaneous metastases, but metastatic cells in lymph nodes were devoid of HNK-1 immunoreactivity. None of the benign pigmented lesions exhibited HNK-1 immunoreactivity. Expression of the HNK-1 glycotope in cutaneous malignant melanoma is an independent prognostic marker of metastasis. Differential HNK-1 expression at the metastatic sites implies that its expression is modulated by the surrounding environment. As HNK-1 is also transiently expressed during migration of melanocyte precursor cells derived from the neural crest, recapitulation of this transient expression might occur during metastatic spread of cutaneous malignant melanoma. 相似文献
102.
John Hopkins Ian McConnell Robert G. Dalziel Bernadette M. Dutia 《European journal of immunology》1993,23(11):2889-2896
This study characterizes antigen-induced phenotypic and functional aspects of major histocompatibility complex (MHC) class II expression on recirculating T cells in efferent lymph. In vivo secondary, but not primary challenge is associated with both kinetic and phenotypic alterations in class II expression by T cells. All three major T cell subsets, CD4+, CD8+ and T19+ (γδ T cell receptor), show an approximate four fold increase in the level of MHC class II expression during secondary responses. No changes in B cell expression of class II were seen. Resting efferent lymph T cells are predominantly either class II? or DR+DQ? but this changes to DR+DQ+ after antigenic challenge. The antigen-presenting function of these class II+ T cells was investigated at daily intervals after in vivo antigenic challenge. T cells from non-activated lymph nodes could not induce proliferation of antigen-specific T cells with soluble antigen but were weakly stimulatory in allo-mixed lymphocyte reaction (MLR) at high (> 2:1) stimulator cell ratios. Activated T cells isolated during secondary in vivo responses, and expressing increased quantities of MHC class II, were positive stimulator cells in the MLR. In contrast these cells could not present soluble antigen or trypsin-digested antigen to the T cell lines. In the MLR assays, the relative stimulation by class II+ T cells correlates with the levels of class II expression. We conclude from these experiments that both quantitative and qualitative changes in MHC class II, induced on T cells under physiological conditions, play a role in the regulation of the immune response in vivo but that that role is not simply one of presentation of soluble antigen. 相似文献
103.
目的:研究大鼠淋巴结淋巴滤泡的生后发育.方法:采用常规组织学、免疫细胞化学及三维重建技术研究了大鼠腘窝淋巴结内淋巴滤泡的发生.结果:生后18天始,淋巴结浅层皮质内sIgM阳性B淋巴细胞聚集形成初级淋巴滤泡.生后3周ED-5阳性滤泡树突状细胞出现.随着鼠龄及体重的增长,初级淋巴滤泡不断扩大,每个淋巴结内淋巴滤泡数亦增多.生后13周滤泡数达高峰,平均每个淋巴结86个,13周以后体重缓慢增长,淋巴滤泡数逐渐下降.生后8周时,次级淋巴滤泡出现,ED-5阳性滤泡树突状细胞主要分布于亮区.结论:初级淋巴滤泡形成过程中B淋巴细胞聚集可能诱导局部网状细胞分化成滤泡树突状细胞;发育期间淋巴滤泡数随体重增长而增加可能与某些决定机体生长的因素作用有关. 相似文献
104.
Jiqing Guo Kyoichi Ono Akinori Noma 《Pflügers Archiv : European journal of physiology》1996,433(1-2):209-211
Under the whole cell clamp, superfusion of the rabbit sinoatrial node cells with a Na+-free solution suppressed the sustained inward current (Ist), and the L-type Ca2+ current (ICa,L) could be recorded on depolarization less negative than –40 mV from the holding potential of –80 mV. On the other hand, replacement
of Ca2+ with Mg2+ in the external solution suppressed inward-going ICa,L and isolated Ist. Under this condition, Ist measured as a nicardipine-sensitive current showed an activation threshold between –60 and –70 mV. The conductance sequence
of Ist for monovalent ions was determined as Na+ > Li+ >> K+ @ Cs+ by replacing the external Na+ with these alkali metal ions. The contribution of Ist to the diastolic depolarization is discussed.
Received: 12 June 1996 / Received after revision: 31 July 1996 / Accepted: 7 August 1996 相似文献
105.
Won -Kyung Ho Hilary F. Brown Denis Noble 《Pflügers Archiv : European journal of physiology》1994,426(1-2):68-74
The ionic selectivity of the hyperpolarizationactivated inward current (i
f) channel to monovalent cations was investigated in single isolated sinoatrial node cells of the rabbit using the whole-cell patch-clamp technique. With a 140 mM K+ pipette, replacement of 90% external Na+ by Li+ caused a –24.5 mV shift of the fully activated current/voltage I/V curve without a significant decrease of the slope conductance. With a 140 mM Cs+ pipette, the i
f current decreased almost proportionally to the decrease in external [Na+]o as Li+ was substituted. These responses are practically the same as those observed with N-methyl glucamine (NMG+) substitution, suggesting that the relative permeability of Li+ compared with Na+ for the i
f channel is as low as that of NMG+. When Cs+ or Rb+ was substituted for internal K+, the fully activated I/V relationship for i
f showed strong inward rectification with a positive reversal potential, indicating low permeability of the i
f channel for Cs+ and Rb+. These results show that the i
f channel is highly selective for Na+ and K+ and will not pass the similar ions Li+ and Rb+. Such a high degree of selectivity is unique and may imply that the structure of the i
f channel differs greatly from that of other Na+ and K+ conducting channels. 相似文献
106.
107.
Pierre Marschall Ruicheng Wei Justine Segaud Wenjin Yao Pierre Hener Beatriz Falcon German Pierre Meyer Cecile Hugel Grace Ada Da Silva Reinhard Braun Daniel H. Kaplan Mei Li 《The Journal of allergy and clinical immunology》2021,147(5):1778-1794
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108.
109.
Christelle Faveeuw Marie-Claude Gagnerault Fran?oise Lepault 《Clinical & developmental immunology》1994,3(4):273-282
Subpopulations of lymphoid cells were compared with respect to their ability to migrate into
peripheral lymphoid organs of nonobese diabetic (NOD) mice and various strains of control
mice. In short-term, in vivo homing studies, no major differences in the pattern of homing
of B and T cells were observed among all mouse strains studied. On the other hand, CD4
cells localized consistently more efficiently than CD8 cells in both PP and LN of adult NOD
and BALB/c mice, whereas both populations migrated roughly equivalently in LN of adult
DBA/2, CBA, and C57BL/6 mice. No age-dependent differences in the homing of CD4 and
CD8 cells were observed in BALB/c mice. On the contrary, in 2-week-old NOD mice, CD4
and CD8 cells migrated equally well. The preferential entry of CD4 cells in adult NOD and
BALB/c did not result from increased blood transit time of CD8 cells. On the other hand,
the preferential migration of CD8 cells was observed in the liver, whereas the two T-cell
subsets migrated equally well in the lungs. The differences in the homing characteristics of
CD4 and CD8 cells among NOD, BALB/c, and C57BL/6 mice were not related to
modifications in the level of expression of adhesion molecules such as MEL-14, LFA-1, and
Pgp-1. 相似文献
110.
结核性淋巴结炎的组织细胞反应性增生变型 总被引:1,自引:0,他引:1
应用结核杆菌DNA123bp特异性序列片段为靶序列的多聚酶链反应(M·TB-PCR)技术、BCG免疫组化(BCG-IHC)技术和抗酸染色(AF)方法,对38例呈现组织细胞反应性增生-碎屑样坏死-嗜中性白细胞渗出病变的淋巴结石蜡包埋组织进行了分支杆菌/结核杆菌的回顾性检测。三种方法的综合阳性率为52.6%(20/38例)。AF、BCG-IHC和M·TB-PCR的各自阳性率分别为0.8%、26.3%和50%。研究结果表明:(1)在按本文标准选择的淋巴结“组织细胞反应性增生”病变中,有半数病例与结核杆菌的感染有关,即结核性淋巴结炎可呈现“组织细胞反应性增生”之类的变型;(2)PCR技术在结核性淋巴结炎的病原学诊断上具有重要价值。 相似文献