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排序方式: 共有767条查询结果,搜索用时 15 毫秒
1.
Julie A. Schmidt Georgina K. Fensom Sabina Rinaldi Augustin Scalbert Paul N. Appleby David Achaintre Audrey Gicquiau Marc J. Gunter Pietro Ferrari Rudolf Kaaks Tilman Kühn Heiner Boeing Antonia Trichopoulou Anna Karakatsani Eleni Peppa Domenico Palli Sabina Sieri Rosario Tumino Bas Bueno-de-Mesquita Antonio Agudo Maria-Jose Sánchez María-Dolores Chirlaque Eva Ardanaz Nerea Larrañaga Aurora Perez-Cornago Nada Assi Elio Riboli Konstantinos K. Tsilidis Timothy J. Key Ruth C. Travis 《International journal of cancer. Journal international du cancer》2020,146(3):720-730
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer. 相似文献
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S F de Medeiros P E Assi M M W Y de Medeiros 《International journal of gynaecology and obstetrics》2004,87(1):24-28
OBJECTIVE: To evaluate the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels in early follicular phase throughout the reproductive years. METHOD: FSH and LH concentrations were determined by radioimmunoassay (RIA). Linear and polynomial regressions were carried out considering basal FSH as the dependent and age as the independent variable. RESULTS: FSH levels increased throughout the reproductive years (P<0.025). A positive correlation between age and basal FSH levels was detected (P<0.05). The Pearson squared coefficient of r(2)=0.889 was obtained. Using polynomial regression, the inclination of the parabole (Y=7.97-0.009x+0.057x(2)) was 0.359 and the generalized correlation coefficient was r=0.795. The goodness of fit analysis showed that the parabole may better represent the phenomenon (F=4.7; P<0.05). The LH levels remained constant, increasing only beyond 40 years of age. CONCLUSION: The FSH levels rose in a nonlinear way during the reproductive life and the LH concentrations increased discreetly only in patients over 40 years of age. 相似文献
4.
Dissociated ROS production and ceramide generation in sulfasalazine-induced cell death in Raw 264.7 cells 总被引:2,自引:0,他引:2
Salh B Assi K Huang S O'Brien L Steinbrecher U Gómez-Muñoz A 《Journal of leukocyte biology》2002,72(4):790-799
Sulfasalazine (SSZ) is a drug used in inflammatory bowel disease, whose precise mechanism of action remains to be clarified. Here, we report that incubation of Raw 264.7 cells with SSZ but not salicylates [acetylsalicylic acid (ASA), 4-aminosalicylic acid (4-ASA), and 5-ASA] causes a mixed apoptotic and necrotic form of cell death. In contrast to its metabolites, sulfapyridine and 5-ASA, SSZ exposure in Raw 264.7 cells resulted in a threefold increase in ceramide generation, as well as a robust production of reactive oxygen species (ROS). However, inhibition of ceramide production by fumonisin B1 failed to attenuate cell death. Preincubation with catalase, cyclosporin A (CsA), and bongkrekic acid attenuated ROS production. When dead cells were quantified for apoptotic versus necrotic cell death, catalase and N-acetylcysteine reproducibly attenuated apoptosis, whereas CsA, in addition to reducing apoptosis, was observed to dramatically enhance necrosis. In conclusion, the cell-death response induced by SSZ in Raw 264.7 cells involves ROS in the apoptotic limb but is independent of ceramide formation. 相似文献
5.
Mohamed Chahine Paul B. Bennett Alfred L. George Jr Richard Horn 《Pflügers Archiv : European journal of physiology》1994,427(1-2):136-142
Full-length deoxyribonucleic acid, complementary (cDNA) constructs encoding the-subunit of the adult human skeletal muscle Na+ channel, hSkM1, were prepared. Functional expression was studied by electrophysiological recordings from cRNA-injectedXenopus oocytes and from transiently transfected tsA201 cells. The Na+ currents of hSkM1 had abnormally slow inactivation kinetics in oocytes, but relatively normal kinetics when expressed in the mammalian cell line. The inactivation kinetics of Na+ currents in oocytes, during a depolarization, were fitted by a weighted sum of two decaying exponentials. The time constant of the fast component was comparable to that of the single component observed in mammalian cells. The block of hSkM1 Na+ currents by the extracellular toxins tetrodotoxin (TTX) and -conotoxin (CTX) was measured. The IC50 values were 25 nM (TTX) and 1.2 M (CTX) in oocytes. The potency of TTX is similar to that observed for the rat homolog rSkM1, but the potency of CTX is 22-fold lower in hSkM1, primarily due to a higher rate of toxin dissociation in hSkM1. Single-channel recordings were obtained from outside-out patches of oocytes expressing hSkM1. The single-channel conductance, 24.9 pS, is similar to that observed for rSkM1 expressed in oocytes. 相似文献
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Sironi M Assi A Quaglia G Tonnarelli G Cozzi L 《Advances in clinical pathology : the official journal of Adriatic Society of Pathology》1999,3(3):55-62
Cytopathological findings on three pedriatic gonadic-extragonadic pure yolk sac tumor are reported: the highly variable histological patterns (reticular, solid, festooning or pseudopapillary, polyvesicular vitelline), reflecting differentiation towards extraembryonic yolk sac structures, are not appreciated in cytologic samples. Since the tumor's cytologic spectrum is very broad, the most diagnostic differential difficulty with yolk sac tumor is adenocarcinoma. The presence of intracellular and extracellular hyaline globules, that are periodic acid-Schiff stain (PAS) positive and diastase resistant and correspond to alpha-fetoprotein production, alpha-fetoprotein positivity of the neoplastic cells; showing nuclear pleomorphism and vacuolated "bubbly" cytoplasm are the most consistent cytologic hallmarks of this neoplasm, which diagnosis would be confirmed by histologic, immunocytochemical and clinical findings. 相似文献
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9.
Frenoy N Gildelgado M Pham P Salvucci M Chahine A Chabli A Misset J Debuire B 《Oncology reports》1996,3(2):385-390
Although lymphoid malignancies have been widely studied at the molecular level, no group has reported on the simultaneous investigation of t(14;18) chromosomal translocation, B-cell clonality and bcl2 gene expression. We have performed PCR analysis of t(14;18) translocation and B-cell clonality as well as semi-quantitation of bcl2 expression by Western blotting on a group of 41 patients treated at our institution for lymphoid malignancies. The t(14;18) translocation was observed in 10 out of 40 cases (25%) with a prevalence in the subgroup of centrofollicular lymphoma (9 out of 19, or 47%, which includes one patient in complete clinical remission). bcl2 was overexpressed in 84% of the patients (21/25) and B monoclonality was observed in 21 out of 37 B-cell neoplasia patients (57%) with or without a t(14;18) translocation. In 4 patients, bcl2 overexpression, which has been implicated in the sensitivity to a variety of cytotoxic drugs, was the only abnormality detected. Studies are currently underway to determine whether semi-quantitation of bcl2 expression provides improved prediction of a patient's response to chemotherapy. 相似文献
10.
M E Bertrand J M Lablanche P Y Tilmant F A Thieuleux M G Delforge R A Chahine 《European heart journal》1983,4(8):532-535
Provocative tests for coronary spasm were performed in a groupof 131 patients (124 men and 7 women) with recent (<6 weeks)transmural myocardial infarction. Coronary arteriography wasperformed 27±9 days after the onset of the infarction.The provocative test was performed using a single IV bolus of0.4 mg of ergometrine. Aortic pressure, ECG and arteriogramsof the two coronary vessels were repeated 3 and 5 min later.Provoked spasm was observed in 27 (21%) of the patients. In13 (48%) the coronary spasm occurred in a vessel presumed tobe responsible for the myocardial infarction, while it was observedin coronary artery unrelated to the area of the infarct in 14(52% of the cases with spasm). Thus, this study demonstratesa high degree of reactivity of the coronary tree of patientswith recent transmural myocardial infarction suggesting thelikelihood of a role for spasm in the infarction process andoffering some explanation for subsequent recurrent ischemicevents. 相似文献