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排序方式: 共有1161条查询结果,搜索用时 15 毫秒
71.
Ramona Erber Miriam Angeloni Robert Sthr Michael P. Lux Daniel Ulbrich-Gebauer Enrico Pelz Agnes Bankfalvi Kurt W. Schmid Robert F. H. Walter Martina Vetter Christoph Thomssen Doris Mayr Frederick Klauschen Peter Sinn Karl Sotlar Katharina Stering Albrecht Stenzinger Marius Wunderle Peter A. Fasching Matthias W. Beckmann Oliver Hoffmann Rainer Kimmig Nadia Harbeck Rachel Wuerstlein Fulvia Ferrazzi Arndt Hartmann 《International journal of molecular sciences》2022,23(15)
In intermediate risk hormone receptor (HR) positive, HER2 negative breast cancer (BC), the decision regarding adjuvant chemotherapy might be facilitated by multigene expression tests. In all, 142 intermediate risk BCs were investigated using the PAM50-based multigene expression test Prosigna® in a prospective multicentric study. In 119/142 cases, Prosigna® molecular subtyping was compared with local and two central (C1 and C6) molecular-like subtypes relying on both immunohistochemistry (IHC; HRs, HER2, Ki-67) and IHC + tumor grade (IHC+G) subtyping. According to local IHC, 35.4% were Luminal A-like and 64.6% Luminal B-like subtypes (local IHC+G subtype: 31.9% Luminal A-like; 68.1% Luminal B-like). In contrast to local and C1 subtyping, C6 classified >2/3 of cases as Luminal A-like. Pairwise agreement between Prosigna® subtyping and molecular-like subtypes was fair to moderate depending on molecular-like subtyping method and center. The best agreement was observed between Prosigna® (53.8% Luminal A; 44.5% Luminal B) and C1 surrogate subtyping (Cohen’s kappa = 0.455). Adjuvant chemotherapy was suggested to 44.2% and 88.6% of Prosigna® Luminal A and Luminal B cases, respectively. Out of all Luminal A-like cases (locally IHC/IHC+G subtyping), adjuvant chemotherapy was recommended if Prosigna® testing classified as Prosigna® Luminal A at high / intermediate risk or upgraded to Prosigna® Luminal B. 相似文献
72.
The serum tocopherol levels were determined on 923 workers (18–62 years of age) from the textile, chemical and metallurgical industries. Tocopherol levels varied between 0,20 and 1,86 mg per 100 ml serum, the mean value being 0,77 ± 0,01 mg per 100 ml, but in 148 subjects (16%) concentrations under 0,5 mg per 100 ml were found. For women the average was significantly (p < 0,05) lower than that for men (0,75 ± 0,02 compared to 0,79 ± 0,01) and the prevalence of levels below 0,5 mg per 100 ml greater (18,4% compared to 12,6%). Independent of sex the serum tocopherol level increased with age (from 0,59 ± 0,02 under 26 years, to 0,87 ± 0,05 mg per 100 ml for the group over 55 years, p < 0,001). By grouping the persons according to the tocopherol levels (A = up to 0,5 mg per 100 ml; B = 0,51–1,0 and C = over 1,0 mg per 100 ml) and by calculating for each group the average values of the daily fat intake (supplied especially by sunflower oil) a relationship was found between the two series of values, but overall this did not reach statistical significance. 相似文献
73.
Influence of air drying temperature on kinetics,physicochemical properties,total phenolic content and ascorbic acid of pears 总被引:1,自引:0,他引:1
Nadia Djendoubi Mrad Nourhène Boudhrioua Nabil Kechaou Francis Courtois Catherine Bonazzi 《Food and Bioproducts Processing》2012,90(3):433-441
This study was conducted to evaluate quality and structural changes in parallelepipedic pieces of pears during convective drying at different air temperatures (30–70 °C).Submitted to atmospheric O2 conditions, ascorbic acid deterioration demonstrated first-order kinetic behaviour and was found to depend on air temperature and pear moisture content. Loss of ascorbic acid content increased with increasing air temperature. Possible explanation could be the irreversible oxidative reaction occurring during drying. Phenol content degradation fitted a pseudo first-order reaction and was significantly influenced by air temperature.Variations in bulk density, shrinkage and porosity essentially depended on changes in moisture content. Porosity exhibited a nonlinear variation with respect to moisture content. Volume change showed, as expected, a linear variation with moisture content. Drying temperature significantly induced the increase of a* and b* colorimetric parameters due to non-enzymatic browning reaction, which turned the samples more reddish and yellow when the temperature rose. 相似文献
74.
As part of the NJ Toxics Reduction Workplan for NY/NJ Harbor, ambient water samples were collected at 15 locations along the tidal portions of the Hackensack, Passaic, Raritan, Rahway and Elizabeth Rivers, and in Newark Bay, the Arthur Kill, and Kill van Kull. A Trace Organics Platform Sampler was used to collect a total of 73 dissolved phase and 73 suspended sediment phase samples between June 2000 and May 2002. These samples were analyzed for spatial and wet versus dry weather trends in the 114 polychlorinated biphenyls (PCBs; modified USEPA Method 1668A). Mean total PCB concentrations at the sampling locations ranged between 3.45 and 56 ng/L. PCB homolog groups distribution patterns at the sampling locations are presented. 相似文献
75.
Cutignano A d'Ippolito G Romano G Lamari N Cimino G Febbraio F Nucci R Fontana A 《Chembiochem : a European journal of chemical biology》2006,7(3):450-456
Enzymatic preparations and specialized analytical tools have shown that chloroplast-derived glycolipids are the main substrates for the biosynthetic pathway that produces antiproliferative polyunsaturated aldehydes in broken cells of the marine diatom Thalassiosira rotula. This process, which is associated with the formation of free fatty acids and lyso compounds from polar lipids but not triglycerides, is largely dependent on glycolipid hydrolytic activity, rather than phospholipase A(2) as previously suggested. Preliminary characterization of lipolytic enzymes has revealed protein bands of 40-45 kDa. Under native conditions these proteins seem to be associated with soluble aggregates that have an apparent molecular weight of approximately 200 kDa. The biochemical process, which is similar to that described in the algal-bloom forming diatom Skeletonema costatum, suggests a mechanism based on decompartmentalization and mixing of preexisting enzymes and substrates. 相似文献
76.
Footskate is a common problem encountered in interactive applications dealing with virtual character animations. It has proven difficult to fix without the use of complex numerical methods, which require expert skills for their implementations, along with a fair amount of user interaction to correct a motion. On the other hand, deformable bodies are being increasingly used in virtual reality (VR) applications, allowing users to customize their avatar as they wish. This introduces the need of adapting motions without any help from a designer, as a random user seldom has the skills required to drive the existing algorithms towards the right solution. In this paper, we present a simple method to remove footskate artifacts in VR applications. Unlike previous algorithms, our approach does not rely on the skeletal animation to perform the correction but rather on the skin. This ensures that the final foot planting really matches the virtual character’s motion. The changes are applied to the root joint of the skeleton only so that the resulting animation is as close as possible to the original one. Eventually, thanks to the simplicity of its formulation, it can be quickly and easily added to existing frameworks. 相似文献
77.
Dr. Ivan Bassanini Dr. Silvia Parapini Dr. Corinna Galli Dr. Nadia Vaiana Dr. Andrea Pancotti Prof. Nicoletta Basilico Prof. Donatella Taramelli Prof. Sergio Romeo 《ChemMedChem》2019,14(23):1982-1994
The treatment of malaria, the most common parasitic disease worldwide and the third deadliest infection after HIV and tuberculosis, is currently compromised by the dramatic increase and diffusion of drug resistance among the various species of Plasmodium, especially P. falciparum (Pf). In this view, the development of new antiplasmodial agents that are able to act via innovative mechanisms of action, is crucial to ensure efficacious antimalarial treatments. In one of our previous communications, we described a novel class of compounds endowed with high antiplasmodial activity, characterized by a pharmacophore never described before as antiplasmodial and identified by their 4,4’-oxybisbenzoyl amide cores. Here, through a detailed structure-activity relationship (SAR) study, we thoroughly investigated the chemical features of the reported scaffolds and successfully built a novel antiplasmodial agent active on both chloroquine (CQ)-sensitive and CQ-resistant Pf strains in the low nanomolar range, without displaying cross-resistance. Moreover, we conducted an in silico pharmacophore mapping. 相似文献
78.
Nawal Makhloufi Nadia Chougui Farouk Rezgui Elias Benramdane Carmen S. R. Freire Carla Vilela Armando J. D. Silvestre 《应用聚合物科学杂志》2021,138(20):50450
The present study investigated the fabrication and characterization of bio-based sustainable films composed of a terrestrial plant raw material, namely Opuntia ficus-indica (OFI) cladodes powder (CP) and a marine seaweed derivative, namely agar (A). The effect of glycerol concentration on the properties of the casted films was evaluated at four different contents, namely 30, 40, 50 and 60 wt%. The films present UV-blocking properties, as well as moderate mechanical performance, thermal stability, and water vapor transmission rate (WVTR). The results point to an increase in thickness, elongation at break, moisture content, water solubility, and WVTR with increasing glycerol content. On the contrary, Young's modulus, tensile strength, and water contact angle decreased as glycerol concentration increased. The best combination is obtained for the film with 30% glycerol, based on an intermediate compromise between physical, mechanical, thermal, and barrier properties. All these outcomes express the potentiality of the powder obtained from grinding the OFI cladodes as raw material to produce low-cost films for the development of sustainable packaging materials. 相似文献
79.
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