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排序方式: 共有7174条查询结果,搜索用时 15 毫秒
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IGF-I, IGFBP-3 and breast cancer in young women: a pooled re-analysis of three prospective studies. 总被引:2,自引:0,他引:2
Sabina Rinaldi Paolo Toniolo Paola Muti Eva Lundin Anne Zeleniuch-Jacquotte Alan Arslan Andrea Micheli Per Lenner Laure Dossus Vittorio Krogh Roy E Shore Karen L Koenig Elio Riboli P?r Stattin Franco Berrino G?ran Hallmans Annekatrin Lukanova Rudolf Kaaks 《European journal of cancer prevention》2005,14(6):493-496
Prospective cohort studies on breast cancer risk among premenopausal women and insulin-like growth factor I (IGF-I) concentrations have so far included only few cases, and have shown inconsistent relative risk estimates. We pooled 220 cases of breast cancer diagnosed before age 50, and 434 control subjects, from three prospective studies in New York (USA), Ume? (Northern Sweden) and Milan (Italy), and we measured IGF-I and insulin-like growth factor binding protein 3 (IGFBP-3) with common enzyme-linked immunosorbent assays. Overall, IGF-I and IGFBP-3 measurements obtained by the common method showed a positive but not significant relationship with breast cancer risk (odds ratios (ORs) 0.90 [95% confidence intervals (95% CI) 0.50-1.62], 1.63 [0.89-2.97], 1.46 [0.78-2.73] and 1.41 [0.75-2.63] for quintiles of IGF-I, and ORs 0.98 [0.54-1.75], 1.06 [0.59-1.91], 1.04 [0.58-1.87] and 1.77 [0.97-3.24] for quintiles of IGFBP-3). Our results give only moderate support for an association of blood IGF-I with breast cancer risk in young women. 相似文献
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This is a prospective interventional clinical study evaluating intraocular inflammation developed after Ultrasound Cyclo Plasty (UCP) for the treatment of glaucoma. Eighteen eyes of 18 patients were treated with UCP second-generation probes (Eye OP1). After treatment, the mean intraocular pressure (IOP) significantly decreased from 26.8±7.2 to 18.8±6.1 mm Hg at day 1 and to 14.7±3.4 mm Hg at month 6 (all P<0.001). Mean laser flare-cell photometry value steeply increased after surgery from 12.1±7.5 to 64.1±53.9 ph/ms (P=0.001) at day 1, and then progressively decreased to respectively 60.6±49.7 at day 7, 43.5±38.5 at day 14 and 28.2±18.3 at month 1 (all P<0.05), returning at levels similar to baseline ones at month 3 and month 6 (respectively 16.7±6.2 and 12.8±10.2, both P>0.05). A significant negative correlation was found between postoperative increase of aqueous flare values and anterior chamber depth (R=-0.568, P=0.014). This timeframe may be considered reasonable for repeating UCP treatment, when required. 相似文献
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Andrea Corrales Paula Martínez Susana García Verónica Vidal Eva García Jesús Flórez Emilio J. Sanchez‐Barceló Noemí Rueda 《Journal of pineal research》2013,54(3):346-358
Ts65Dn mice (TS), the most commonly used model of Down syndrome (DS), exhibit phenotypic characteristics of this condition. Both TS mice and DS individuals present cognitive disturbances, age‐related cholinergic degeneration, and increased brain expression of β‐amyloid precursor protein (AβPP). These neurodegenerative processes may contribute to the progressive cognitive decline observed in DS. Melatonin is a pineal indoleamine that has been reported to reduce neurodegenerative processes and improve cognitive deficits in various animal models. In this study, we evaluated the potentially beneficial effects of long‐term melatonin treatment on the cognitive deficits, cholinergic degeneration, and enhanced AβPP and β‐amyloid levels of TS mice. Melatonin was administered for 5 months to 5‐ to 6‐month‐old TS and control (CO) mice. Melatonin treatment improved spatial learning and memory and increased the number of choline acetyltransferase (ChAT)‐positive cells in the medial septum of both TS and CO mice. However, melatonin treatment did not significantly reduce AβPP or β‐amyloid levels in the cortex or the hippocampus of TS mice. Melatonin administration did reduce anxiety in TS mice without inducing sensorimotor alterations, indicating that prolonged treatment with this indoleamine is devoid of noncognitive behavioral side effects (e.g., motor coordination, sensorimotor abilities, or spontaneous activity). Our results suggest that melatonin administration might improve the cognitive abilities of both TS and CO mice, at least partially, by reducing the age‐related degeneration of basal forebrain cholinergic neurons. Thus, chronic melatonin supplementation may be an effective treatment for delaying the age‐related progression of cognitive deterioration found in DS. 相似文献
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ABSTRACT: BACKGROUND: Projection pursuit regression, multilayer feed-forward networks, multivariate adaptive regression splines and trees (including survival trees) have challenged classic multivariable models such as the multiple logistic function, the proportional hazards life table Cox model (Cox), the Poisson's model, and the Weibull's life table model to perform multivariable predictions. However, only artificial neural networks (NN) have become popular in medical applications. RESULTS: We compared several Cox versus NN models in predicting 45-year all-cause mortality (45- ACM) by 18 risk factors selected a priori: age; father life status; mother life status; family history of cardiovascular diseases; job-related physical activity; cigarette smoking; body mass index (linear and quadratic terms); arm circumference; mean blood pressure; heart rate; forced expiratory volume; serum cholesterol; corneal arcus; diagnoses of cardiovascular diseases, cancer and diabetes; minor ECG abnormalities at rest. Two Italian rural cohorts of the Seven Countries Study, made up of men aged 40 to 59 years, enrolled and first examined in 1960 in Italy. Cox models were estimated by: a) forcing all factors; b) a forward-; and c) a backward-stepwise procedure. Observed cases of deaths and of survivors were computed in decile classes of estimated risk. Forced and stepwise NN were run and compared by Cstatistics (ROC analysis) with the Cox models. Out of 1591 men, 1447 died. Model global accuracies were extremely high by all methods (ROCs > 0.810) but there was no clear-cut superiority of any model to predict 45-ACM. The highest ROCs (> 0.838) were observed by NN. There were inter-model variations to select predictive covariates: whereas all models concurred to define the role of 10 covariates (mainly cardiovascular risk factors), family history, heart rate and minor ECG abnormalities were not contributors by Cox models but were so by forced NN. Forced expiratory volume and arm circumference (two protectors), were not selected by stepwise NN but were so by the Cox models. CONCLUSIONS: There were similar global accuracies of NN versus Cox models to predict 45-ACM. NN detected specific predictive covariates having a common thread with physical fitness as related to job physical activity such as arm circumference and forced expiratory volume. Future attention should be concentrated on why NN versus Cox models detect different predictors. 相似文献
67.
Ignacio Mejía‐Calvo Leonardo E. Lpez‐Jurez Said Vzquez‐Leyva Carlos A. Lpez‐Morales Daniel Montoya‐Escutia Pamela G. Merlos Rivera Jos Enrique Herbert‐Pucheta Luis Gerardo Zepeda‐Vallejo Marco Velasco‐Velzquez Lenin Pavn Sonia M. Prez‐Tapia Emilio Medina‐Rivero 《Journal of Cosmetic Dermatology》2021,20(1):150-158
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