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排序方式: 共有469条查询结果,搜索用时 265 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
2.
Amniotic fluid acid protease and acid protease inhibitory activities were examined in normal pregnancies as a function of gestational age. The acid proteolytic activity of the amniotic fluid is almost constant during gestational weeks 16-29 (26 +/- 13 micrograms globin/ml/2 hrs, mean +/- SD, n = 64). The activity sharply increases after 29 weeks in a time-dependent fashion and reaches a value of 302 +/- 89 (mean +/- SD, n = 13) at 39-40 weeks gestation. Under standard conditions, the ability of amniotic fluid to inhibit bovine pepsin declined during gestation in a linear fashion from 44 +/- 13% (mean +/- SD, n = 36) at 16-18 weeks to 9 +/- 10% (mean +/- SD, n = 41) at 36-40 weeks. A correlation coefficient of r = 0.72 was found between pepsin inhibitory activity and gestational age. No consistent change was noted in the extent of inhibition of the endogenous acid protease throughout pregnancy. In 61 amniotic fluid samples, a correlation coefficient of r = 0.70 was found between acid protease activity and the lecithin/sphingomyelin (L/S) ratio. During the course of this study, five cases of respiratory distress syndrome (RDS) were diagnosed clinically. All five infants had a low protease activity (55 +/- 22 micrograms globin/ml/2 hr, mean +/- SD) as well as a low L/S ratio (0.68 +/- 0.20, mean +/- SD). In contrast, no case of RDS of the newborn was observed among 29 pregnancies with high protease activity and a high L/S ratio. The present observations may suggest a predictive value of amniotic fluid acid protease activity in assessment of fetal lung maturity. 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
5.
Assi F Fruscio R Bonardi C Ghidini A Allavena P Mantovani A Locatelli A 《BJOG : an international journal of obstetrics and gynaecology》2007,114(2):143-147
OBJECTIVE To investigate the role of pentraxin 3 (PTX3), an acute-phase protein produced by cells of innate immunity in response to inflammatory signals, in spontaneous preterm delivery (PTD). DESIGN Cohort study. SETTING Department of Obstetrics and Gynecology of the University of Milano-Bicocca. POPULATION Forty-six pregnant women with preterm rupture of membranes (n=33) or preterm labour with intact membranes (n=13) delivering at <34 weeks of gestation and 34 women with uncomplicated pregnancies (control group). METHODS We compared plasma and vaginal PTX3 levels between study group and controls, and in women with versus women without clinical or histologic evidence of intrauterine infection using statistical analysis. MAIN OUTCOME MEASURES Peak PTX3 concentration. RESULTS Peak PTX3 concentration in plasma samples of study group was significantly higher than that in controls (1175, 0-9630 versus 650, 0-1450 pg/ml; P=0.0003) but not in vaginal swabs (1660, 0-6604 versus 457, 0-4649 pg/ml; P=0.386). PTX3 levels in plasma were significantly higher in women with placenta vasculopathy compared with that in women with no placental lesions (2910, 0-9630 versus 636, 0-5692 pg/ml; P=0.04). Peak plasma and vaginal PTX3 concentrations were not significantly different in women with versus women without intrauterine infection (1168, 0-7110 versus 845, 0-9630 pg/ml, P=0.34 and 1975, 471-6604 versus 1919, 0-4150 pg/ml, P=0.38, respectively). CONCLUSIONS Spontaneous PTD is associated with a significant increase of maternal plasma concentrations of PTX3. PTX3 seems to be a marker of placenta vasculopathy rather than intrauterine infection. 相似文献
6.
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
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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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