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991.
C. ÖRNDAL B. CARLÉN† M. ÅKERMAN† H. WILLÉN† N. MANDAHL S. HEIM§ A. RYDHOLM‡ F. MITELMAN 《Cytopathology》1991,2(5):261-270
A multidisciplinary approach was taken to characterize a soft tissue tumour. In smears prepared from aspirated material, uniform tumour cells, embedded in a myxoid matrix and partly arranged in a lace-like pattern, were found. Histopathology showed a lace-like pattern of cells in a matrix of hyaluronidase-stable mucins. Cytoplasmic positivity for S-100 protein was found in some tumour cells. Electron microscopic analysis revealed intracisternal aggregates of microtubules. All these features are consistent with the diagnosis of extraskeletal myxoid chondrosarcoma (EMC). DNA flow cytometry showed a diploid DNA content. Cytogenetic examination revealed the tumour karyotype 45, XY, t(2;11)(q31;p15), t(9;22)(q22.3;q12), dic(13;22)(p11;p13). Because similar 9;22-translocations have been described in two other cases of EMC, we conclude that t(9;22)(q22–31;q11–12) is a specific rearrangement in this tumour type. Cytogenetic analysis may thus be of diagnostic value in the examination of tumours with this and similar histologies. 相似文献
992.
Summary The workerless, inquiline ant,Doronomyrmex kutteri has isolated populations with a haploid chromosome number ofn=23 both in the Alps (Swiss and South Tyrolean Alps) and in Sweden, and a population withn=25 in southern Germany. Crossbreeding of sexuals from all populations proved successful. Backcrosses of F1-females with males from the parental populations produced F2-females, and hybrid males withn=23, 24, or 25 chromosomes. The chromosome polymorphism is not due to B-chromosomes. Probably then=25 karyotype originated from then=23 karyotype by two Robertsonian fissions (2 ¯M 4 ¯A), since then=25 karyotype was found in only one of the populations. Diploid males occurred frequently in colonies from four out of five sites investigated. 相似文献
993.
本文描述了改进的简单、快捷、效果好的植物花粉母细胞分裂时期染色体致畸研究的制片技术程序,及其在环境生物研究中的重要意义。它比其它技术节省时间达24~30小时。 相似文献
994.
Although it has been known that there is an X-chromosome imprinting effect during early embryogenesis in female mammals, it remains unknown if parental origin of the X chromosome has an effect in males. Furthermore, it has not been possible to produce animals with normal sex chromosomes of uniparental origin to further evaluate such imprinting effects. We have devised a breeding scheme to produce male mice, designated XPYP males, in which both the X and Y chromosomes are paternally inherited. To our knowledge, these are the first mammals produced that have a normal sex chromosome constitution but with both sex chromosomes derived from one parent. Development and reproduction in these XPYP males and the sex ratio and chromosome constitution of their offspring appeared normal; thus there is no apparent effect in males of having both sex chromosomes derive from one parent or of having the X chromosome derived from an inappropriate parent. Although we have detected no X-chromosome imprinting effect in these males, evidence from other sources suggest that the X chromosome is parentally imprinted. Thus detection and definition of an imprint can depend on the assay used. 相似文献
995.
The influence of electrochemical gradients of Na+ and K+ upon the membrane binding and pore forming activity of the terminal complement proteins 总被引:2,自引:0,他引:2
Summary The hemolytic activity of the terminal complement proteins (C5b-9) towards erythrocytes containing high potassium concentration has been reported to be dramatically increased when extracellular Na+ is substituted isotonically by K+ (Dalmasso, A.P., et al., 1975,J. Immunol.
115:63–68). This phenomenon was now further investigated using resealed human erythrocyte ghosts (ghosts), which can be maintained at a nonlytic osmotic steady state subsequent to C5b-9 binding: (1) The functional state of C5b-9-treated ghosts was studied from their ability to retain trapped [14C]-sucrose or [3H]-inulin when suspended either in the presence of Na+ or K+. A dramatic increase in the permeability of the ghost membrane to both nonelectrolytes-in the absence of significant hemoglobin release-was observed for C5b-9 assembly in the presence of external K+. (2) The physical binding of the individual125I-labeled terminal complement proteins to ghost membranes was directly measured as a function of intra- and extracellular K+ and Na+. The uptake of125I-C7,125I-C8, and125I-C9 into membrane C5b-9 was unaltered by substitution of Na+ by K+. (3) The binding of the terminal complement proteins to ghosts subjected to a transient membrane potential generated by the K+-ionophore valinomycin (in the presence of K+ concentration gradients) was measured. No significant change in membrane binding of any of the C5b-9 proteins was detected under the influence of both depolarizing and hyperpolarizing membrane potentials. It can be concluded that the differential effect of Na+ versus K+ upon the erythrocyte membrane isnot due to an effect upon the binding of the complement proteins to the membraneper se, but upon the functional properties of the assembled C5b-9 pore site. 相似文献
996.
A famillialy inherited paracentric inversion of human chromosome 7 is described. The breakpoints are localized in the bands
q1 1.2 and q2 2.1. The similarity between the inverted chromosome 7 and the chromosome 6 of the gorilla characterizes this
inversion as a reverse chromosomal mutation. The parallels between human chromosome pathology and the chromosomal evolution
of Pongidae and man are discussed. 相似文献
997.
J M Ibson J J Waters P R Twentyman N M Bleehen P H Rabbitts 《Journal of cellular biochemistry》1987,33(4):267-288
Twelve cell lines isolated from patients with small cell lung cancer have been studied for amplification of the three characterised members of the myc proto-oncogene family (c-myc, N-myc, and L-myc) and for abnormalities of chromosome 3. Ten of these lines were being studied for the first time. Ten of the 12 small cell lung cancer cell lines had amplification of one member of the myc proto-oncogene family. Amplification of c-myc was observed in only one small cell lung line--a "morphological variant". One "classic" small cell lung cancer line expressed c-myc but had no obvious amplification of the gene. N-myc and L-myc were more commonly amplified than c-myc. Chromosomal abnormalities (mainly deletions) in chromosome 3 were observed in all small cell lung carcinoma cell lines examined. When the small cell lung carcinoma lines were grouped according to "classic" or "variant" characteristics, it was found that the "classics" had deletions of the short arm of chromosome 3, whereas the "biochemical variants" had deletions of the long arm of chromosome 3. The extent of the deletions varied between cell lines. For the deletion in the short arm of chromosome 3 the minimum common region of overlap was assigned to bands 3p23-3p24. 相似文献
998.
Porcine malignant hyperthermia carrier detection and chromosomal assignment using a linked probe 总被引:4,自引:0,他引:4
In pigs, the gene for glucosephosphate isomerase (GPI) is linked to the halothane (HAL) gene which is responsible for malignant hyperthermia (MH). A single copy DNA probe, designated GPI8R, has been isolated from a pig genomic library using a porcine GPI cDNA probe. This probe detects, as was the case for the cDNA probe, a five allele polymorphism in SacI and PvuII digested pig DNA. Family studies show that this polymorphism is linked to the HAL locus and hence can be used in carrier detection. In situ hybridization with GPI8R assigned the GPI locus to bands p12-q22 of chromosome 6. We conclude that the HAL linkage group resides on chromosome 6. 相似文献
999.
Hairy root cultures, obtained after transformation of seven plant species by A. rhizogenes, were examined cytologically to assess their chromosome number. All species had the correct 2n diploid number of chromosomes in root tip cells. Free cell suspensions of two of the species were also examined and were found to be variable with polyploids or aneuploids predominating. The DNA from the hairy root cultures was isolated and the presence of the Agrobacterium T-DNA confirmed by Southern blotting. The relevance of these observations to the use of hairy roots in the study of plant secondary metabolite production is discussed. 相似文献
1000.
Pancreatic and salivary amylase cDNA probes have been used to search for new DNA fragment length variation among a total of 43 inbred mouse strains. Fragment length differences found with three restriction endonucleases grouped the strains into two major classes. The segregation of these variant fragments has been analyzed among several sets of recombinant inbred strains and is presented here. Previously reported differences for strains YBR and CE have been confirmed. New segregation data for carbonic anhydrase, a locus near the proximal end of mouse chromosome 3, are presented. 相似文献