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排序方式: 共有5354条查询结果,搜索用时 15 毫秒
71.
72.
Sonja Loges Gerhard Heil Melanie Bruweleit Volker Schoder Martin Butzal Uta Fischer Ursula M Gehling Gunter Schuch Dieter K Hossfeld Walter Fiedler 《Journal of clinical oncology》2005,23(6):1109-1117
PURPOSE: Bone marrow neoangiogenesis plays an important pathogenetic and possible prognostic role in acute myeloid leukemia (AML). Members of the vascular endothelial growth factor (VEGF) and angiopoietin family represent the most specific inducers of angiogenesis secreted by AML blasts. We therefore correlated expression of angiogenic factors with clinical variables. PATIENTS AND METHODS: We investigated the expression of VEGF-A, VEGF-C, angiopoietin-1 (Ang1), angiopoietin-2 (Ang2), and the receptor Tie2 by quantitative polymerase chain reaction in a cohort of 90 patients younger than 61 years with de novo AML entered into the German AML Süddeutsche H?moblastose Gruppe Hannover 95 trial. Uni- and multivariate analyses were performed using clinical and gene expression variables. RESULTS: Univariate analysis of overall survival indicated the following variables as prognostic factors: good response on a day-15 bone marrow examination after initiation of induction chemotherapy, karyotype, and high Ang2 expression. In multivariate analysis, only bad response and log Ang2 expression remained of statistical significance, with a hazard ratio of 3.51 (95% CI, 1.91 to 6.47) and 0.75 (95% CI, 0.61 to 0.91), respectively. Subgroup analysis suggested that the prognostic impact of Ang2 expression was especially evident in cohorts with low VEGF-C and Ang1 mRNA levels. CONCLUSION: These results show that expression of Ang2 represents an independent prognostic factor in AML. Additional research into interactions of angiogenic cytokines in the pathogenesis of bone marrow angiogenesis in AML is warranted. 相似文献
73.
Tarja Anttila Leena Tenkanen Sonja Lumme Maija Leinonen Randi Elin Gislefoss G?ran Hallmans Steinar Thoresen Timo Hakulinen Tapio Luostarinen P?r Stattin Pekka Saikku Joakim Dillner Matti Lehtinen Matti Hakama 《Cancer epidemiology, biomarkers & prevention》2005,14(2):385-389
OBJECTIVE: We assessed the risk of prostate cancer by exposure to Chlamydia trachomatis. METHOD: Seven hundred thirty eight cases of prostate cancer and 2,271 matched controls were identified from three serum sample banks in Finland, Norway, and Sweden by linkage to the population based cancer registries. RESULTS: A statistically significant inverse association (odds ratio, 0.69; 95% confidence interval, 0.51-0.94) was found. It was consistent by different serotypes and there was a consistent dose-response relationship. CONCLUSION: C. trachomatis infection is not likely to increase the risk of prostate cancer. Whether the inverse relationship is true or due to difficulties in measuring the true exposure in prostatic tissue by serology, confounders or other sources of error remain open. 相似文献
74.
Aman U Buzdar Nuhad K Ibrahim Deborah Francis Daniel J Booser Eva S Thomas Richard L Theriault Lajos Pusztai Marjorie C Green Banu K Arun Sharon H Giordano Massimo Cristofanilli Debra K Frye Terry L Smith Kelly K Hunt Sonja E Singletary Aysegul A Sahin Michael S Ewer Thomas A Buchholz Donald Berry Gabriel N Hortobagyi 《Journal of clinical oncology》2005,23(16):3676-3685
PURPOSE: The objective of this study was to determine whether the addition of trastuzumab to chemotherapy in the neoadjuvant setting could increase pathologic complete response (pCR) rate in patients with human epidermal growth factor receptor 2 (HER2) -positive disease. PATIENTS AND METHODS: Forty-two patients with HER2-positive disease with operable breast cancer were randomly assigned to either four cycles of paclitaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide or to the same chemotherapy with simultaneous weekly trastuzumab for 24 weeks. The primary objective was to demonstrate a 20% improvement in pCR (assumed 21% to 41%) with the addition of trastuzumab to chemotherapy. The planned sample size was 164 patients. RESULTS: Prognostic factors were similar in the two groups. After 34 patients had completed therapy, the trial's Data Monitoring Committee stopped the trial because of superiority of trastuzumab plus chemotherapy. pCR rates were 25% and 66.7% for chemotherapy (n = 16) and trastuzumab plus chemotherapy (n = 18), respectively (P = .02). The decision was based on the calculation that, if study continued to 164 patients, there was a 95% probability that trastuzumab plus chemotherapy would be superior. Of the 42 randomized patients, 26% in the chemotherapy arm achieved pCR compared with 65.2% in the trastuzumab plus chemotherapy arm (P = .016). The safety of this approach is not established, although no clinical congestive heart failure was observed. A more than 10% decrease in the cardiac ejection fraction was observed in five and seven patients in the chemotherapy and trastuzumab plus chemotherapy arms, respectively. CONCLUSION: Despite the small sample size, these data indicate that adding trastuzumab to chemotherapy, as used in this trial, significantly increased pCR without clinical congestive heart failure. 相似文献
75.
Anna van Rhenen Nicole Feller Angèle Kelder August H Westra Elwin Rombouts Sonja Zweegman Marjolein A van der Pol Quinten Waisfisz Gert J Ossenkoppele Gerrit Jan Schuurhuis 《Clinical cancer research》2005,11(18):6520-6527
PURPOSE: In CD34-positive acute myeloid leukemia (AML), the leukemia-initiating event originates from the CD34(+)CD38(-) stem cell compartment. Survival of these cells after chemotherapy may lead to minimal residual disease (MRD) and subsequently to relapse. Therefore, the prognostic impact of stem cell frequency in CD34-positive AML was investigated. EXPERIMENTAL DESIGN: First, the leukemogenic potential of unpurified CD34(+)CD38(-) cells, present among other cells, was investigated in vivo using nonobese diabetic/severe combined immunodeficient mice transplantation experiments. Second, we analyzed whether the CD34(+)CD38(-) compartment at diagnosis correlates with MRD frequency after chemotherapy and clinical outcome in 92 AML patients. RESULTS: In vivo data showed that engraftment of AML blasts in nonobese diabetic/severe combined immunodeficient mice directly correlated with stem cell frequency of the graft. In patients, a high percentage of CD34(+)CD38(-) stem cells at diagnosis significantly correlated with a high MRD frequency, especially after the third course of chemotherapy. Also, it directly correlated with poor survival. In contrast, total CD34(+) percentage showed no such correlations. CONCLUSIONS: Both in vivo data, as well as the correlation studies, show that AML stem cell frequency at diagnosis offers a new prognostic factor. From our data, it is tempting to hypothesize that a large CD34(+)CD38(-) population at diagnosis reflects a higher percentage of chemotherapy-resistant cells that will lead to the outgrowth of MRD, thereby affecting clinical outcome. Ultimately, future therapies should be directed toward malignant stem cells. 相似文献
76.
Christoph Seger Harald R?mpp Sonja Sturm Ernst Haslinger Peter C Schmidt Franz Hadacek 《European journal of pharmaceutical sciences》2004,21(4):453-463
Supercritical fluid extracts (carbon dioxide without modifiers) of St. John's Wort (Hypericum perforatum L., Clusiaceae) were analyzed by GC-MS, HPLC-DAD and HPLC-DAD-MS. Besides the dominating phloroglucinols hyperforin (36.5 +/- 1.1%) and adhyperforin (4.6 +/- 0.1%), the extracts mainly contained alkanes (predominantly nonacosane), fatty acids and wax esters. The apolar components tended to accumulate in a waxy phase resting a top of the hyperforin-enriched phase. No components of higher polarity like naphthodianthrones were found. A set of hyperforin oxidation products was detected and tentatively assigned using HPLC-MS. 相似文献
77.
Prof. Dr. med. Uwe Janssens Prof. Dr. med. Hilmar Burchardi Univ.-Prof. Dr. med. Gunnar Duttge Renate Erchinger Dr. med. Peter Gretenkort Prof. Dr. med. Michael Mohr Univ.-Prof. Dr. med. Friedemann Nauck Sonja Roth?rmel Prof. Dr. med. Fred Salomon Univ.-Prof. Dr. med. P. Schmucker PD Dr. phil. Alfred Simon Prof. Dr. med. Herwig Stopfkuchen Prof. Dr. med. Andreas Valentin Univ.-Prof. Dr. med. Norbert Weiler Dr. med. Gerald Neitzke 《MedR Medizinrecht》2012,30(10):647-650
78.
Donald D. Raymond Mary E. Piper Sonja R. Gerrard Georgios Skiniotis Janet L. Smith 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(47):19208-19213
Rift Valley fever and Toscana viruses are human pathogens for which no effective therapeutics exist. These and other phleboviruses have segmented negative-sense RNA genomes that are sequestered by a nucleocapsid protein (N) to form ribonucleoprotein (RNP) complexes of irregular, asymmetric structure, previously uncharacterized at high resolution. N binds nonspecifically to single-stranded RNA with nanomolar affinity. Crystal structures of Rift Valley fever virus N-RNA complexes reconstituted with defined RNAs of different length capture tetrameric, pentameric and hexameric N-RNA multimers. All N-N subunit contacts are mediated by a highly flexible α-helical arm. Arm movement gives rise to the three multimers in the crystal structures and also explains the asymmetric architecture of the RNP. Despite the flexible association of subunits, the crystal structures reveal an invariant, monomeric RNP building block, consisting of the core of one N subunit, the arm of a neighboring N, and four RNA nucleotides with the flanking phosphates. Up to three additional RNA nucleotides bind between subunits. The monomeric building block is matched in size to the repeating unit in viral RNP, as visualized by electron microscopy. N sequesters four RNA bases in a narrow hydrophobic binding slot and has polar contacts only with the sugar-phosphate backbone, which faces the solvent. All RNA bases, whether in the binding slot or in the subunit interface, face the protein in a manner that is incompatible with base pairing or with “reading” by the viral polymerase. 相似文献
79.
Paul Störchle Wolfram Müller Marietta Sengeis Helmut Ahammer Alfred Fürhapter-Rieger Norbert Bachl Sonja Lackner Sabrina Mörkl Sandra Holasek 《Ultrasound in medicine & biology》2017,43(2):427-438
A recently standardized ultrasound technique for measuring subcutaneous adipose tissue (SAT) was applied to normal-weight, overweight and obese persons. Eight measurement sites were used: upper abdomen, lower abdomen, erector spinae, distal triceps, brachioradialis, lateral thigh, front thigh and medial calf. Fat compression was avoided. Fat patterning in 38 participants (body mass index: 18.6–40.3 kgm?2; SAT thickness sums from eight sites: 12–245 mm) was evaluated using a software specifically designed for semi-automatic multiple thickness measurements in SAT (sound speed: 1450 m/s) that also quantifies embedded fibrous structures. With respect to ultrasound intra-observer results, the correlation coefficient ρ = 0.999 (p < 0.01), standard error of the estimate = 1.1 mm and 95% of measurements were within ±2.2 mm. For the normal-weight subgroup, the median measurement deviation was 0.43 mm (1.1% of mean thickness), and for the obese/overweight subgroup it was 0.89 mm (0.5%). The eight sites used here are suggested to represent inter-individual differences in SAT patterning. High measurement accuracy and reliability can be obtained in all groups, from lean to overweight and obese, provided that measurers are trained appropriately. 相似文献
80.
Sonja Wörner Hans-Konrad Mueller-Hermelink Hans-Ullrich Voelker 《Pathology, research and practice》2018,214(2):207-212
In the present study, 21 cases of adult/late-onset EBV-associated lymphoproliferative disease (AELPD) with an uncertain malignant potential were investigated with regard to their histomorphology, immunophenotype, clonal rearrangement of the heavy chain (IgH) and T-cell receptor (TCR) genes and clinical course.The cases were histomorphologically reevaluated and assigned to one of three morphological groups: mononucleosis-like, Hodgkin-like, or polymorphous. In addition, cases with or without detectable necrosis were investigated for differences in clinical outcome.Overall survival was highest in the group with Hodgkin-like morphology (4/4 patients), followed by patients with mononucleosis-like phenotype (4/5 patients surviving). Cases with polymorphous morphology showed the poorest survival rates with 7/12 patients dead of disease (58%). 4/6 patients with histologically detectable necrosis died (66%), but only 4/15 patients without necrosis (27%). 11/21 cases with AELPD showed clonal rearrangement for IgH (n?=?4), TCR (n?=?5) or IgH?+?TCR (n?=?2). 5/11 patients with clonal rearrangement died (45%), and this percentage was similar in all of the three subgroups.In conclusion, the present study shows that polymorphous morphology and detection of necrosis in AELPD are frequently linked to a fatal clinical course, whereas Hodgkin-like morphology seems to be associated with a more favourable prognosis. Clonal rearrangement of IgH or TCR is frequent in AELPD, but prognosis is unpredictable from this feature. 相似文献