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71.
The evaluation of the shear capacity of an FRP-strengthened reinforced-concrete beam is challenging due to the complex interaction between different contributions provided by the concrete, steel stirrup and FRP reinforcement. The shape of the beam and the FRP inclination can have paramount importance that is not often recognized by the models that are suggested by codes. The interaction among different resisting mechanisms has a significant effect on the shear capacity of beams, since it can cause a reduction in the efficiency of some resisting mechanisms. A comparative study of the performance in the shear resistance assessment provided by three models with six different effectiveness factors (R) is performed, considering different cross-section shapes, FRP wrapping schemes, inclination and anchorage systems. The results revealed that the cross-section shape, the FRP inclination and the efficiency of the FRP anchorages have a significant effect on the shear strength of beams. The analysis results show that the three models are able to provide an accurate average estimation of shear strength (but with a coefficient of variation up to 0.35) when FRP reinforcement orthogonal to the beam axis is considered, while a significant underestimation (up to 19%) affected the results for inclined FRP reinforcement. Moreover, all the models underestimated the resistance of beams with a T section.  相似文献   
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ObjectiveThe aim of the study was to investigate the potential clinical relevance of immunohistochemically assessed RON expression in a large, single institution series of primary untreated advanced ovarian cancer patients.MethodsImmunohistochemical analysis was performed by using the polyclonal rabbit anti-RON-β antibody (C-20, clone sc-322, Santa Cruz, California). Results were expressed as the total proportion of immunostained tumor cells (RON positivity), or the percentage of cells showing strong staining of RON expression (H-RON positivity).ResultsIn the overall series RON positive immunoreaction was observed in 103/141 cases, while H-Ron positivity was detected in 577141 (40.4%) cases. No association between RON and H-RON expression with response to first-line treatment was documented. During the follow up period, progression and death of disease were observed in 111 (78.7%) and 76 (53.9%) cases, respectively. Cases with strong H-RON expression has a shorter overall survival (median = 35 months) than cases with low RON levels (median = 59 months) (X2 = ? 2.1, p value = 0.032). In multivariate analysis, only platinum resistance, and extent of residual tumor retained an independent negative prognostic role for OS, with the percentages of H-RON positively immunostained cells showing a borderline statistical significance (p value = 0.0643). The unfavourable role of elevated percentages of H-RON expression was maintained only in the subgroup of platinum resistant recurrent ovarian cancer patients (X2 = 3.89, p value = 0.048) compared to the platinum sensitive ones (X2 = 1.98, p value = 0.16).ConclusionsThe assessment of RON expression deserves further attention as a parameter helpful to identify poor prognosis ovarian cancer patients potentially candidates to investigational agents.  相似文献   
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Raul Zamora-Ros  Valerie Cayssials  Mazda Jenab  Joseph A. Rothwell  Veronika Fedirko  Krasimira Aleksandrova  Anne Tjønneland  Cecilie Kyrø  Kim Overvad  Marie-Christine Boutron-Ruault  Franck Carbonnel  Yahya Mahamat-Saleh  Rudolf Kaaks  Tilman Kühn  Heiner Boeing  Antonia Trichopoulou  Elissavet Valanou  Effie Vasilopoulou  Giovanna Masala  Valeria Pala  Salvatore Panico  Rosario Tumino  Fulvio Ricceri  Elisabete Weiderpass  Torkjel M. Sandanger  Cristina Lasheras  Antonio Agudo  Maria-Jose Sánchez  Pilar Amiano  Carmen Navarro  Eva Ardanaz  Emily Sonestedt  Bodil Ohlsson  Lena Maria Nilsson  Martin Rutegård  Bas Bueno-de-Mesquita  Kay-Thee Khaw  Nicholas J. Wareham  Kathryn Bradbury  Heinz Freisling  Isabelle Romieu  Amanda J. Cross  Paolo Vineis  Augustin Scalbert 《European journal of epidemiology》2018,33(11):1063-1075
Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and subclasses of polyphenols and CRC risk and its main subsites, colon and rectum, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The cohort included 476,160 men and women from 10 European countries. During a mean follow-up of 14 years, there were 5991 incident CRC cases, of which 3897 were in the colon and 2094 were in the rectum. Polyphenol intake was estimated using validated centre/country specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, a doubling in total dietary polyphenol intake was not associated with CRC risk in women (HRlog2?=?1.06, 95% CI 0.99–1.14) or in men (HRlog2?=?0.97, 95% CI 0.90–1.05), respectively. Phenolic acid intake, highly correlated with coffee consumption, was inversely associated with colon cancer in men (HRlog2?=?0.91, 95% CI 0.85–0.97) and positively associated with rectal cancer in women (HRlog2?=?1.10, 95% CI 1.02–1.19); although associations did not exceed the Bonferroni threshold for significance. Intake of other polyphenol classes was not related to colorectal, colon or rectal cancer risks. Our study suggests a possible inverse association between phenolic acid intake and colon cancer risk in men and positive with rectal cancer risk in women.  相似文献   
76.
Short-term dietary restriction has been proposed as an intriguing pre-operative conditioning strategy designed to attenuate the surgical stress response and improve outcomes. However, it is unclear how this nutritional intervention influences the microbiome, which is known to modulate the systemic condition. Healthy individuals were recruited to participate in a four-day, 70% protein-restricted, 30% calorie-restricted diet, and stool samples were collected at baseline, after the restricted diet, and after resuming normal food intake. Taxonomy and functional pathway analysis was performed via shotgun metagenomic sequencing, prevalence filtering, and differential abundance analysis. High prevalence species were altered by the dietary intervention but quickly returned to baseline after restarting a regular diet. Composition and functional changes after the restricted diet included the decreased relative abundance of commensal bacteria and a catabolic phenotype. Notable species changes included Faecalibacterium prausnitzii and Roseburia intestinalis, which are major butyrate producers within the colon and are characteristically decreased in many disease states. The macronutrient components of the diet might have influenced these changes. We conclude that short-term dietary restriction modulates the ecology of the gut microbiome, with this modulation being characterized by a relative dysbiosis.  相似文献   
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Despite the rising evidence in favor of immunotherapy (IT), the treatment of oncological patients affected by so-called “cold tumors” still represents an open issue. Cold tumors are characterized by an immunosuppressive (so-called cold) tumor microenvironment (TME), which favors host immune system suppression, cancer immune-escape, and a worse response to IT. However, the TME is not a static element, but dynamically mutates and can be changed. Radiotherapy (RT) can modulate a cold microenvironment, rendering it better at tumor killing by priming the quiescent host immune system, with a consequent increase in immunotherapy response. The combination of TME radiomodulation and IT could therefore be a strategy for those patients affected by cold tumors, with limited or no response to IT. Thus, this review aims to provide an easy, rapid, and practical overview of how RT could convert the cold TME and why cold tumor radiomodulation could represent an interesting strategy in combination with IT.  相似文献   
79.
A multi-analytical approach was employed to study wall paintings located in the Sotterra church at Paola, in the province of Cosenza, Italy. The site is an underground church (hence the name of Sotterra, which means “under the earth”) rediscovered in the second half of the 19th century, during the building works of the Madonna del Carmine church on the same area. This underground church preserves valuable mural paintings having different styles. The construction’s dating and overlapped modifications made until the site was abandoned is also debated. A wall painting, depicting “The Virgin” as part of the “Annunciation and the Archangel Gabriel” present on the opposite side of the apse, was selected and investigated using both in situ and laboratory-based analysis. Preliminarily, the non-destructive investigations involved several analytical techniques (IR imaging, UV-Induced Visible Fluorescence, and X-ray Fluorescence analyses) that provided mapping and characterization of pictorial layers and first data about deterioration phenomena. On the basis of this information, a more in-depth study was conducted on micro-fragments aimed at characterizing the stratigraphy and to identify the artist’s technique. Cross-sections were analysed using polarized optical microscopy and electron scanning microscopy coupled with energy-dispersive X-ray spectroscopy to obtain morphological and chemical information on the selected pictorial micro-fragments of the wall painting. The results allowed to characterize the pigments and provide better readability of the whole figure, revealing details that are not visible to the naked eye, important for future historical-artistic and conservative studies. The results represent the first step of a systematic archaeometric research aimed at supporting the ongoing historical-stylistic studies to distinguish the different building phases hypothesized for this religious site which remained buried for three centuries.  相似文献   
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