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81.
A complex translocation [t(2;10;11)(q34;q11;q13)], an extra chromosome #8, and a duplication of 17q were the major findings in blast cells found in the bone marrow of a 5-yr-old boy with AML-M2 both before treatment and during relapse. The child died 8.5 mo after diagnosis, despite intensive combination chemotherapy. 相似文献
82.
Transmission electron microscopy (TEM) of peripheral nerve in rats receiving 6% lead carbonate for 4-10 weeks provided evidence of a specific Schwann cell injury, associated with demyelination. Intranuclear inclusions in Schwann cells appeared within 2 weeks of administration of a lead-containing diet. Swelling of Schwann cells and disintegration of their cytoplasm was evident at 4 weeks. Distinctive electron-dense inclusions appeared in both Schwann and endothelial cells during the period of intoxication and were ultrastructurally identical to pathognomonic inclusions of lead poisoning seen in renal tubular epithelial cells. Scanning microscopy (SEM) with electron-probe microanalysis was used to identify the lead-containing deposits. In addition to Schwann cell changes, vessels revealed endothelial cell injury and alteread permeability to macromolecules. Since morphologic changes of Schwann cells precede the development of altered vascular permeability and endoneurial edema, it appears that lead gains access to the endoneurium prior to the development of altered vascular permeability, suggesting that edema and altered endoneurial fluid pressure are epiphenomena that supervene after demyelination occurs. Remyelination, Schwann cell proliferation and formation of onion bulbs are manifestations of persistent toxic injury to myelin-sustaining cells, resulting in chronic demyelination. 相似文献
83.
We report observations on the behavior of Sertoli cells in sparse culture during the period from the time of plating to the time of initial confluence (the transitional remodeling phase). Changes in shape, structure, and polarity of cells, as well as changes in migration patterns and cell-cell association patterns, have been followed during the transitional remodeling phase with the aid of topographical markers. These markers are based upon differences between ultrastructural features of the basolateral and apicolateral surfaces. The basolateral surface is characterized by plasmalemmal blebs, whereas the apicolateral surface is characterized by filopodial extensions. Structural differences observed in situ remain evident in Sertoli cells isolated by sequential enzymatic treatments that are described. Another marker is provided by laminin-binding sites, which are detected exclusively on the blebbed, basolateral surfaces of freshly prepared Sertoli cell aggregates. The orientation described is sustained during the initial radial migration of Sertoli cells explanted on uncoated glass coverslips. Under these conditions, blebs are detected only on the dorsal surfaces, and filopodial extensions are evident only on the ventral surfaces. In contrast, Sertoli cells sparsely plated on a reconstituted basement membrane (air-dried Matrigel) migrate rapidly, display an extraordinary capacity to form elaborate cytoplasmic extensions for cell-cell and cell-substratum contacts, and readily retract blebs and filopodial extensions. These cells do not form mosaic borders, whereas cells plated on uncoated glass do form a monolayer with mosaic-like borders. Cells sparsely seeded on gelated Matrigel migrate preferentially at gaps between adjacent cell explants, and develop a compact cell-cell association pattern. These cells display few, if any, cytoplasmic extensions. We compare the behavior of Sertoli cells sparsely plated on Matrigel with the behavior of Sertoli cells in situ during different stages of development. 相似文献
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Fritz H. Bach M.D. Charles E. Morrow M.D. David E. R. Sutherland M.D. Ph.D. 《World journal of surgery》1984,8(2):204-206
As demonstrated by Faustman et al., islets that are pretreated with Ia antibodies and complement show markedly prolonged survival as compared with islets, with the same immunogenetic disparity, without antibody pretreatment. In order to test whether it is simply the absence of an allo-Ia disparity that accounts for this finding, we have transplanted islets across class I disparities alone; in certain cases, such islets are rapidly rejected. Yet, even though there is no allo-Ia difference on such islets, pretreatment of the islets with anti-Ia monoclonal antibody also results in markedly prolonged survival. We suggest that the presence of Ia antigens may serve as a differentiation marker for cells that can present class I antigens in an immunogenic manner; further, allo-Ia antigens can lead to a stronger anti-class I rejection response. 相似文献
86.
Müller Alejandro Cornejo Wachtler Benjamin Lampert Thomas 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(8):1026-1026
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Ein Erratum zu dieser Publikation wurde veröffentlicht: https://doi.org/10.1007/s00103-019-03081-y 相似文献
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Biology
New treatment selection criteria will arise from molecular biology parameters of growth and treatment response, most probably coupled with the increasing use of initial chemotherapy and repeated minimally invasive surgery.Prevention
Secondary and hopefully also primary prevention of breast cancer will become more and more successful in the era of molecular genetics, and such interventions will be more directed to individuals and groups at defined higher risk.Surgery
Surgery will increasingly tend towards “minimally invasive surgery,” which favors not only cosmetics and quality of life, but also more appropriate imaging follow-up.Chemotherapy
Primary (preoperative) chemo- and endocrine therapy will become the standard initial form of breast cancer treatment, with the intent of down-staging of the tumors to allow later breast-conserving procedures, but also to use the tumor as a biological response parameter and hopefully also for better clinical outcome.Cost — Effectiveness
Economical parameters might become more and more decisive, as we will have to live with much more “evidence based medicine” and with much more restricted allocation of resources in the future. This might mean, that we will have to diligently develop more simple and cheaper, but not prognostically worse treatment strategies in years to come. More specifically: Do we still need all of the traditional steps in diagnosis and treatment of breast cancer in order to achieve the same results?Gain of Life
Finally in all of this, we have to make clearcut assumptions, supported also by society and people involved: How do we value “gained years of life” in breast cancer adjuvant and prevention trials? This certainly is not predominantly a medical or economical, but rather an ethical, social and political problem, which has to be finally answered by our socio-cultural environment, and not by doctors alone. 相似文献90.
Lampert Fritz Christiansen Holger Berner Frank Terpe Hans-Joachim Berthold Frank 《Journal of neuro-oncology》1997,31(1-2):181-184
Tumor specimens of 203 infants with neuroblastomas of different clinical stages — registered in successive multicenter clinical trials of the German Society of Pediatric Oncology — could be examined for N-myc amplification, chromosome 1-ploidy and — structure, CD44 std. expression (in tumor tissue, and also in patients sera).Eightyseven (= 43%) of these infants had a non-localized, disseminated neuroblastoma, mainly involving sympathetic nerve tissue, lymphnodes, liver, skin, bone marrow and bones (46 patients were classified into the 4s group, 41 patients in the true 4 group).If the clinical classification between stage 4 and stage 4swas neglected, then 17 of these infants (= 20%) had N-myc amplification (4—64 copies) with 16 already dead. Seven of 9 examined patients with true stage 4 had chromosome 1p aberrations (with N-myc amplification in 5), and among the dead there were 2 with CD44 negative expression.In another series, serum CD44 std. was measured by ELISA, and the highest (significantly different) Kruskal-Wallis mean rank values (147.8) were found in infants (n = 6) with stage 4s compared to the low mean-rank-value of 71.9 in patients with stage 4 (n = 65). Stage 1—3 patients (n = 42) had values of 99.8—88.6.Thus, infants with disseminated neuroblastomas, showing non-diploidy, normal chromosome 1p structure, non-N-myc amplification and high CD44 std. expression in tumor tissue, and also high CD44 std. values in serum, will have the highest chance of survival due to tumor-non-progression.On the other hand, N-myc amplification in the tumor cells was found to be characteristic for stage 4s neuroblastoma patients with tumor progression (n=6). Therefore, 4s neuroblastoma-patients with N-myc amplified tumors should be aggressively treated like true stage 4 tumor patients! 相似文献