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21.
Diffuse type of senile plaques in the cerebellum of Alzheimer-type dementia demonstrated byβ protein immunostain 总被引:5,自引:0,他引:5
Summary We studied senile plaques (SP) in the cerebella of six autopsied subjects with Alzheimer-type dementia (ATD) and ten non-ATD autopsied subjects between the ages of 78 and 90. Neither SP nor amyloid angiopathy (AA) was observed in any of the non-ATD subjects. In the four of the six ATD subjects, diffuse plaques in the molecular layer were seen as ill-defined areas of fine fibrillar materials by protein immunostaining with formic acid pretreatment, the modified Bielschowsky stain, and periodic acid-methenamine silver (PAM) stain. The plaques were not visible with Bodian, Congo red, or periodic acid-Schiff stains. Compact plaques in the Purkinje cell or in the granular cell layers were found in three of the six subjects. Their amyloid core was often surrounded by areolar amyloid deposits. AA was observed in three of the six subjects. The argyrophilia of the diffuse and compact plaques, demonstrated by the modified Bielschowsky and PAM stains, became undetectable when the sections were first treated with formic acid. Such treatment made the plaques immunoreactive with protein antiserum. The findings suggested that cerebellar diffuse plaques and compact plaques consist mainly of an amyloid component, and are characteristic of ATD. 相似文献
22.
目的:探讨nm23—H1基因mRNA在乳腺患组织中的表达及其与临床的关系.方法:采用半定量RT—PCR方法,检测30例乳腺患组织nm23—H1的表达.结果:①淋巴结阳性的原发灶组织nm23—H1 mRNAA表达明显低于淋巴结阴性的原发灶组织,Ⅲ期乳腺患组织nm23—H1 mRNA水平较Ⅰ、Ⅱ期的明显低.②多因素分析发现淋巴结转移与nm23—H1 mRNA的表达有显著性相关.结论nm23—H1基因mRNA表达强度与淋巴结转移呈负相关.在乳胰患转移过程中,nm23—H1 mRNA起重要的作用。 相似文献
23.
24.
小鼠第一次卵裂周期中线粒体分布的变化 总被引:2,自引:0,他引:2
用线粒体专一性活体荧光染色剂罗丹明123显示小鼠受精卵在第一次卵裂周期中M的分布变化,雌原核和雄原核在汇合之前,M在细胞质中呈弥散状随机分布,两原核汇合后,M在核周围略显聚集,第一次卵裂后期,M沿纺锤体微管和2个子核周围集中,但在赤道区域内明显稀少,预示出细胞分裂面的定位,这说明细胞质分裂是收综环收缩和细胞结构调整共同作用的结果。2-细胞阶段,M在细胞核周围明显聚集。2-细胞胚受秋水仙素作用后,M 相似文献
25.
浸润和转移是恶性肿瘤的重要特征,也给肿瘤的治疗带来困难,是预后不良的重要因素.转移抑制因子23(non-metastasis,NM23)基因是最早发现的抗肿瘤转移基因之一.现在已经发现NM23是一个基因家族,包括NM23-H1、NM23-H2等重要的基因家族成员.研究表明NM23基因表达与实体瘤转移抑制有关,在很多实体瘤中可以作为进展和预后的分子标记.随着对NM23基因调控肿瘤转移的分子机制的研究的进一步开展,已经发现了一些NM23肿瘤转移抑制通路上下游的相关调控分子,为进一步的信号通路研究创造了条件.本文概述了近年来对NM23基因转移抑制通路研究的新近展,提出了以后可能的研究方向和需要解决的关键问题. 相似文献
26.
Chromosome aberrations in B-cell chronic lymphocytic leukemia: reassessment based on molecular cytogenetic analysis 总被引:13,自引:0,他引:13
Döhner H Stilgenbauer S Döhner K Bentz M Lichter P 《Journal of molecular medicine (Berlin, Germany)》1999,77(2):266-281
In B-cell chronic lymphocytic leukemia (B-CLL) clonal chromosome aberrations are detected in approximately 40–50% of tumors
when using conventional chromosome banding analysis. Most studies find trisomy 12 to be the most frequent chromosome aberration,
followed by structural aberrations of the long arm of chromosomes 13 and 14. Trisomy 12 and the ”14q+” marker are associated
with shorter survival times, while the patients with 13q abnormalities have a favorable outcome, similar to those with a normal
karyotype. The development of molecular cytogenetic techniques has greatly improved our ability to detect chromosome aberrations
in tumor cells. Using fluorescence in situ hybridization, chromosome aberrations can be detected not only in dividing cells
but also in interphase nuclei, an approach referred to as interphase cytogenetics. The prevalence of specific aberrations in B-CLL is currently being reassessed by interphase cytogenetics. By far the most
frequent abnormality are deletions involving chromosome band 13q14, followed by deletions of the genomic region 11q22.3-q23.1,
trisomy 12, deletions of 6q21-q23, and deletions/mutations of the TP53 tumor suppressor gene at 17p13. The evaluation of the true incidence of these aberrations now provides the basis for more
accurate correlations with clinical characteristics and outcome. Deletions/mutations of the TP53 gene have been shown to be associated with resistance to treatment and to be an independent marker for poor survival. 11q
deletions have been associated with extensive nodal involvement, rapid disease progression, and short survival times. Whether
trisomy 12, 13q14, and 6q deletions have a prognostic impact awaits further study. The application of these molecular cytogenetic
techniques will also contribute to the identification of the pathogenetically relevant genes that are affected by the chromosome
aberrations in B-CLL.
Received: 2 February 1998 / Accepted: 31 March 1998 相似文献
27.
Brice Poreau Francis Ramond Radu Harbuz Véronique Satre Claire Barro Claire Vettier Véronique Adouard Julien Thevenon Pierre‐Simon Jouk Charles Coutton Klaus Dieterich 《American journal of medical genetics. Part A》2019,179(4):650-654
The AMME syndrome defined as the combination of Alport syndrome, intellectual disability, midface hypoplasia, and elliptocytosis (AMME) is known to be a contiguous gene syndrome associated with microdeletions in the region Xq22.3q23. Recently, using exome sequencing, missense pathogenic variants in AMMECR1 have been associated with intellectual disability, midface hypoplasia, and elliptocytosis. In these cases, AMMECR1 gene appears to be responsible for most of the clinical features of the AMME syndrome except for Alport syndrome. In this article, we present two unrelated male patients with short stature, mild intellectual disability or neurodevelopmental delay, sensorineural hearing loss, and elliptocytosis harboring small microdeletions identified by array‐CGH involving TMEM164 and AMMECR1 genes and SNORD96B small nucleolar RNA for one patient, inherited from their mothers. These original cases further confirm that most specific AMME features are ascribed to AMMECR1 haploinsufficiency. These cases reporting the smallest microdeletions encompassing AMMECR1 gene provide new evidence for involvement of AMMECR1 in the AMME phenotype and permit to discuss a phenotype related to AMMECR1 haploinsufficiency: developmental delay/intellectual deficiency, midface hypoplasia, midline defect, deafness, and short stature. 相似文献
28.
IL-12家族新成员及其在免疫应答中的重要调节作用 总被引:3,自引:0,他引:3
白细胞介素-12(Interleukin-12, IL-12)家族成员IL-12、 IL-23、 IL-27三者及其各自受体在结构上的相似性, 使得它们在发挥调节NK细胞活性、 T细胞增殖和细胞因子产生以及抗体类别转换等方面的功能相互重叠但又不完全相同.而2007年发现的该家族的另一新成员IL-35, 结构上虽与其他3个成员同源, 但却具有独特的生物学功能, 是一种主要由调节性T细胞(Treg)分泌的抑制性细胞因子.IL-12家族各成员以及同其他细胞因子之间存在着相互协同、相互拮抗的网络, 不仅在细胞内感染及炎症过程中起着重要的调节作用, 而且与银屑病、多发性硬化症、 Crohn' s病等多种临床疾病的发病密切相关.IL-12家族相关生物制品在自身免疫性疾病、感染性疾病以及肿瘤的治疗中有着广阔的应用前景. 相似文献
29.
30.
Pia Bjrck Carina Elenstrm-Magnusson Anders Rosn Eva Severinson Staffan Paulie 《European journal of immunology》1993,23(8):1771-1775
We have previously found that interleukin-4 and CD40 monoclonal antibodies (mAb) are strong potentiatiors of homotypic B cell aggregation which is dependent on LFA-1. We show here that CD23 mAb were also able to inhibit aggregation to a similar extent as LFA-1 antibodies. This inhibition was restricted to the MHM6 epitope of CD23 and antibodies to other epitopes [Epstein-Barr virus (EBV) CS-1, EBV CS-2, EBV CS-5 and mAb 25] or occupation of the Fc-binding site by IgE had no or a slightly enhancing effect on aggregation. When testing two antibodies to CD21, the recently defined ligand for CD23, one of these (BU32) was found to be inhibitory whereas the other (THB5) had no effect. By combining antibodies to LFA-1 and CD23, aggregation was often completely inhibited. These data suggest that LFA-1/ICAM-1 and CD23/CD21 are the major molecules involved in homotypic aggregation of human B cells. 相似文献