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41.
Thorvardur R Halfdanarson Nathan R Foster George P Kim Michael G Haddock Shaker R Dakhil Robert J Behrens Steven R Alberts 《The oncologist》2022,27(7):534
BackgroundThis North Central Cancer Treatment Group (NCCTG) N064A (Alliance) phase II trial evaluated upfront chemoradiotherapy incorporating the EGFR inhibitor panitumumab, followed by gemcitabine and panitumumab for unresectable, non-metastatic pancreatic cancer.MethodsThe treatment consisted of fluoropyrimidine and panitumumab given concurrently with radiotherapy followed by gemcitabine and panitumumab for 3 cycles followed by maintenance panitumumab. The primary endpoint was the 12-month overall survival (OS) rate and secondary endpoints included confirmed response rate (RR), OS, progression-free survival (PFS), and adverse events. Enrollment of 50 patients was planned and the study fully accrued.ResultsFifty-two patients were enrolled, but only 51 were treated and included in the analysis. The median age of patients was 65 years and 54.9% were women. Twenty-two patients received at least 1 cycle of systemic therapy following radiotherapy, but 29 patients received chemoradiotherapy only without receiving subsequent chemotherapy after completion of chemoradiotherapy. The overall RR was 5.9% (95% CI: 1.2%-16.2%). The 12-month OS rate was 50% (95% CI: 38%-67%) which fell short of the per-protocol goal for success (51.1%). The median PFS was 7.4 months (95% CI: 4.5-8.6) and the median OS was 12.1 months (95% CI 7.9-15.9). Grade 3 or higher adverse events were reported by 88%.ConclusionThe combination of panitumumab, chemotherapy, and external beam radiation therapy was associated with very high rates of grades 3-4 toxicities and survival results did not meet the trial’s goal for success. This regimen is not recommended for further study (ClinicalTrials.gov Identifier ). NCT00601627相似文献
42.
蓣知子皂甙IV的结构 总被引:5,自引:1,他引:5
从木通科木通属植物白木通[Akebia trifoliata(Thunb.)Koidz.var.australis(Diels)Rehd]种子的乙醇提取物中以硅胶层析等方法得四种三萜皂甙。其中甙IV是新天然产物,命名为蓣知子皂甙IV(yuzhiziosideIV)。根据化学和光谱分析,确定甙IV的结构为3-O-β-D-吡喃木糖基-(1→2)-a-L-吡喃阿拉伯糖齐墩果酸-28-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖酯甙。另外皂甙B(I)、皂甙C(II)和皂甙D(III)为已知物。这些化合物在白木通种子中均是首次得到。 相似文献
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47.
An endogenous digitalis-factor derived from the adrenal gland: studies of adrenocortical tumor cells
The present studies demonstrate that the murine adrenocortical tumor cell line Y-1 releases a digoxin-like immunoreactive material into both serum-supplemented nutrient medium and minimal Krebs-Ringer bicarbonate medium. Release of pregnenolone into minimal medium from these cells was consistently inhibited by addition of the cholesterol side-chain cleavage inhibitor aminoglutethimide. However, release of digoxin-like immunoreactivity (DLI) was not similarly affected. To exclude the possibility that DLI could be accounted for by cross-reaction with another known adrenal steroid, aminoglutethimide inhibition was accompanied by inhibition of 17 alpha-hydroxylase with SU-10603 and inhibition of 3 beta-hydroxysteroid dehydrogenase with cyanoketone. Once again, pregnenolone release was effectively inhibited, but no similar pattern of inhibition of DLI release was observed. Increasing the time of the incubation periods from 1 to 2 h did not change the pattern of secretion of pregnenolone or DLI. HPLC analysis of DLI released over prolonged culture periods into serum-supplemented nutrient medium showed high levels of DLI in a single major and several adjacent peaks. Analysis of the ability of extracts of Y-1-conditioned medium to compete with tritiated ouabain for binding to erythrocytes indicates that conditioned medium contained highly enriched levels of ouabain-like activity. On HPLC analysis, the distribution of this activity showed partial correlation with the distribution of DLI. These observations indicate that Y-1 cells produce and release significant quantities of a material with cardiac glycoside-like properties reflected in the cross-reactivity with antidigoxin antibodies and the ability to compete with ouabain for binding to erythrocytes. In substantiation of previous findings in chopped adrenal cultures, the cardiac glycoside-like activity does not appear to result from cholesterol side-chain cleavage or pregnenolone production, since inhibition of side-chain cleavage as well as subsequent 17 alpha-hydroxylation and 3 beta-dehydrogenation did not result in consistent inhibition of DLI release. 相似文献
48.
Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
49.
Charpentier MJ Van Horn RC Altmann J Alberts SC 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(6):1988-1992
When females mate with multiple males, paternal care is generally expected to be negligible, because it may be difficult or impossible for males to discriminate their own offspring from those of other males, and because engaging in paternal care may reduce male mating opportunities. Consequently, males in multimale societies are not predicted to provide direct benefits to their offspring. We have recently demonstrated, however, that males in a typical multimale primate society (yellow baboons, Papio cynocephalus) discriminate their own offspring from those of other males and provide care to them in the form of repeated support during agonistic encounters. This observation raises the question of whether fathers enhance offspring fitness in this species. Here we use 30 years of data on age at maturity for 118 yellow baboons with known fathers. We show that the father's presence in the offspring's social group during the offspring's immature period accelerated the timing of physiological maturation in daughters. Sons also experienced accelerated maturation if their father was present during their immature period, but only if the father was high ranking at the time of their birth. Because age at reproductive maturity has a large impact on lifetime reproductive success, our results indicate a direct effect of paternal presence on offspring fitness. This relationship in turn suggests that the multiple roles that males play in multimale animal societies have not been sufficiently examined or appreciated and that paternal effects may be more pervasive than previously appreciated. 相似文献
50.
E. Marra N. Kroone E. Freriks C.L. van Dam C.J. Alberts A.A. Hogewoning S. Bruisten A. van Dijk M.M. Kroone T. Waterboer M.F. Schim van der Loeff 《The Journal of infection》2018,76(4):393-405