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21.
M Oosterveld S Suciu G Verhoef B Labar A Belhabri C Aul D Selleslag A Ferrant P Wijermans F Mandelli S Amadori U Jehn P Muus R Zittoun U Hess O Anak F Beeldens R Willemze T de Witte 《Leukemia》2003,17(5):859-868
This report used the framework of a large European study to investigate the outcome of patients with and without an HLA-identical sibling donor on an intention-to-treat basis. After a common remission-induction and consolidation course, patients with an HLA-identical sibling donor were scheduled for allogeneic transplantation and patients lacking a donor for autologous transplantation. In all, 159 patients alive at 8 weeks from the start of treatment were included in the present analysis. In total, 52 patients had a donor, 65 patients did not have a donor and in 42 patients the availability of a donor was not assessed. Out of 52 patients, 36 (69%) with a donor underwent allogeneic transplantation (28 in CR1). Out of 65 patients, 33 (49%) received an autograft (27 in CR1). The actuarial survival rates at 4 years were 33.3% (s.e. = 6.7%) for patients with a donor and 39.0% (s.e. = 6.5%) for patients without a donor (P = 0.18). Event-free survival rates were 23.1% (s.e. = 6.2%) and 21.5% (s.e. = 5.3%), respectively (P = 0.66). Correction for alternative donor transplants did not substantially alter the survival of the group without a donor. Also, the survival in the various cytogenetic risk groups was not significantly different when comparing the donor vs the no-donor group. This analysis shows that patients with high-risk myelodysplastic syndrome and secondary acute myeloid leukemia may benefit from both allogeneic and autologous transplantation. We were unable to demonstrate a survival advantage for patients with a donor compared to patients without a donor. 相似文献
22.
Chy-3 mice are Vegfc haploinsufficient and exhibit defective dermal superficial to deep lymphatic transition and dermal lymphatic hypoplasia. 总被引:1,自引:0,他引:1
Michael T Dellinger Robert J Hunter Michael J Bernas Marlys H Witte Robert P Erickson 《Developmental dynamics》2007,236(8):2346-2355
Recent advances in molecular lymphology and lymphatic phenotyping techniques in small animals offer new opportunities to delineate mutant mouse models. Chy-3 mutant mice were originally named for their chylous ascites, but the underlying lymphatic disorder was not defined. We now re-examined these mice and applied advanced genotyping and lymphatic phenotyping techniques to pinpoint the specific lymphatic defect in this mouse model. We demonstrated that Chy-3 mice carry a large chromosomal deletion that includes Vegfc and narrowed this region by monitoring the heterozygosity of genetic markers. We found that Chy-3 mice not only exhibited chylous ascites but also lymphedema of the hind paws and, in approximately half of the males, lymphedema of the penis. Visual lymphangiography and immunofluorescence staining showed a hypoplastic dermal lymphatic network, whereas the blood vasculature appeared unaffected. This hypoplastic lymphatic network was functional, and all adult Chy-3 mice exhibited a lateral lymphatic pathway directly connecting the inguinal to the axillary lymph node. The dermal superficial to deep lymphatic connections in upper limbs and in all cervical regions were intact and functionally drained the upper body. Lymphatic tracer was not transported from the dermal to the deep truncal lymphatic system in the lower limbs, even though the deep lymphatic vessels and nodes were present and patent. These findings further delineate the lymphatic phenotype of Chy-3 mice, identify a collateral lymph drainage pathway previously undescribed in other genetic models of lymphedema, and demonstrate a predilection for lymphatic abnormalities of the lower limbs. 相似文献
23.
BACKGROUND: The Study Centre of the German Surgical Society (SDGC) designs, conducts, and analyses multicentre randomised controlled surgical trials. The aim of this paper is to present the decision-making process and responsibilities of the SDGC from submission of a study idea to full protocol development in order to achieve transparency in trial selection. METHODS: The process is divided into four steps. Study ideas can be submitted electronically by members of the German Surgical Society using a form via the homepage of the institution. Firstly, ideas are screened by staff members within 4 weeks for methodological and clinical relevance. Feasible and novel ideas are then converted to trial outlines in cooperation with the submitting surgeon. As a third step, the Steering Committee of the SDGC decides whether to accept the project using a list of defined criteria. Finally, the SDGC draws up a full protocol together with the submitting surgeon. All ideas and decisions are accessible via the SDGC homepage. CONCLUSIONS: The process described should help in the selection of relevant projects, acquisition of grants, and maintenance of transparency in trial selection and the protocol development process. 相似文献
24.
25.
Summary Fourteen patients with Ph'-chromosome positive chronic myelogenous leukemia (CML) in first chronic phase were treated with recombinant interferon-2c. Interferon-2c 5 to 10×106 units s.c. was given for 12 weeks as an induction therapy. Maintenance treatment consisted of interferon-2c 5 × 106 units twice weekly s.c.. Two patients (14%) attained a complete clinical remission and 6 (43%) a partial remission, 3 of whom developed progressive disease during maintenance therapy. A complete disappearance of Ph'-chromosome was achieved in 1 patient. All patients had a more than 45% initial decline of the leukocyte count. Four out of ten patients with an initially enlarged spleen demonstrated reduction in spleen size. Influenza-like symptoms, anorexia, nausea, weight loss and fatigue were common side effects. Interferon-alpha is active in CML but additional clinical investigations are warranted to assess more precisely the therapeutic value of the interferons in this disease. 相似文献
26.
New methods for the detection of ECG and EOG artefacts in the EEG are introduced, which can also be used for the evaluation
of the quality of the elimination procedure. These algorithms are based on the estimation of the power or coherence spectrum
by means of FFT. The advantage of this method is that the EEG spectrum is monitored by the test algorithm. The spectrum will
be plotted if no influence of the ECG and EOG can be found. On the other hand, if artefacts are detected the correction of
the EEG time series will be carried out and the spectrum of the corrected EEG time series will be plotted after repeated monitoring
by the test algorithm. 相似文献
27.
Matthias Löhle Thomas Müller Carola Wicher Marcus Roedel Harald Schubert Otto W. Witte Peter W. Nathanielsz Matthias Schwab 《The Journal of physiology》2005,564(2):575-588
Synthetic glucocorticoids are administered to pregnant women in premature labour to accelerate fetal lung maturation at a time when fetal cerebrovascular and endocrine systems are maturing. Exposure to glucocorticoids at 0.8–0.9 of gestation increases peripheral and cerebrovascular resistance (CVR) in fetal sheep. We examined whether the increase of CVR and its adverse effect on cerebral blood flow (CBF) depend on the current level of maturation of the pituitary–adrenal axis and the cerebrovascular system. Using fluorescent microspheres, regional CBF was measured in 11 brain regions before and 24 h and 48 h after the start of 3.3 μg kg−1 h−1 betamethasone ( n = 8) or vehicle ( n = 7) infusions to fetal sheep at 0.73 of gestation. Hypercapnic challenges were performed before and 24 h after the onset of betamethasone exposure to examine betamethasone effects on cerebrovascular reactivity. Betamethasone exposure decreased CBF by approximately 40% in all brain regions after 24 h of infusion ( P < 0.05). The decline in CBF was mediated by a CVR increase of 111 ± 16% in the cerebral cortex and 129 ± 29% in subcortical regions ( P < 0.05). Hypercapnic cerebral vasodilatation and associated increase in CBF were blunted ( P < 0.05). Fetal CBF recovered after 48 h of betamethasone administration. There were no differences in glucocorticoid induced CBF and CVR changes compared with our previous findings at 0.87 of gestation. We conclude that the cerebrovascular effects of antenatal glucocorticoids are independent of cerebrovascular maturation and preparturient increase in activity of the fetal pituitary–adrenal axis. 相似文献
28.
In the identified neurons B1, B2 and B3 of Helix pomatia an intracellular injection of Na+ induced an outward current in 10% and an inward current in 90% of the experiments. The outward current was associated with an increase and the inward current with a decrease of the membrane conductance. Both currents reversed at membrane potentials of between -60 and -70 mV. Inward currents were also elicited by intracellular Li+ or tris-[hydroxymethyl]-aminomethane (Tris+) injection. All inward currents were reduced by extracellular administration of tetraethylammonium or quinine. It is suggested that the outward current represents a calcium-activated potassium current and that the inward current is due to a blockade of potassium channels from the intracellular side. 相似文献
29.
DNA microarray analysis reveals novel gene expression profiles in collagen-induced arthritis 总被引:4,自引:0,他引:4
Thornton S Sowders D Aronow B Witte DP Brunner HI Giannini EH Hirsch R 《Clinical immunology (Orlando, Fla.)》2002,105(2):155-168
Global gene expression was analyzed in early and late collagen-induced arthritis (CIA). Of 8734 cDNAs analyzed, 330 were induced and 55 downregulated greater than twofold in early or late disease. Hierarchical clustering of these 385 cDNAs demonstrated five distinct expression patterns differentiating early from late disease and correlating with histopathologic changes in the paw. Of the 385 cDNAs, 185 are known, characterized genes, the majority of which are not described as playing a role in arthritis. However, several of these genes are involved in pathological processes relating to arthritis, including apoptosis, inflammation, and cellular proliferation. One interesting gene, follistatin-like gene, is highly expressed along the margin of contact between inflammatory synovial pannus and eroding bone, suggesting a role in joint destruction. These results demonstrate that global gene expression profiles distinguish early and late CIA and reveal several genes novel to arthritis the further characterization of which will advance our understanding of arthritis. 相似文献
30.
Influence of transferable genetic determinants on the outcome of typing methods commonly used for Enterococcus faecium 总被引:4,自引:0,他引:4
Werner G Willems RJ Hildebrandt B Klare I Witte W 《Journal of clinical microbiology》2003,41(4):1499-1506
A variety of methods is used for a molecular typing of Enterococcus spp. and related gram-positive bacteria including macrorestriction analysis using pulsed-field gel electrophoresis (PFGE), ribotyping, rapid amplification of polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP). To test the influence of transferable determinants on the outcome of different typing methods commonly used for enterococci, we established a homogenous strain collection of 24 transconjugants resulting from filter matings with antibiotic-resistant Enterococcus faecium. As expected, AFLP, RAPD, and PFGE all identified our model bacteria as strongly related. However, distinct differences in the resolving and discriminatory power of the tested methods could be clearly addressed. In PFGE, 22 of 24 transconjugants possessed less than a three-band difference to the recipient pattern and would be regarded as strongly related. Three different RAPD PCRs were tested; in two reactions, identical patterns for all transconjugants and the recipient were produced. One RAPD PCR produced an identical pattern for 18 transconjugants and the recipient and a clearly different pattern for the remaining 6 transconjugants due to a newly appearing fragment resulting from acquisition of the tetL gene. AFLP clusters all transconjugants into a group of major relatedness. Percent similarities were highly dependent on the method used for calculating the similarity coefficient (curve-based versus band-based similarity coefficient). Fragment patterns of digested plasmids showed the possession of nonidentical plasmids in most transconjugants. PFGE still could be recommended as the method of choice. Nevertheless, the more-modern AFLP approach produces patterns of comparable discriminatory power while possessing some advantages over PFGE (less-time-consuming internal standards). Plasmid fingerprints can be included to subdifferentiate enterococcal isolates possessing identical macrorestriction and PCR typing patterns. 相似文献