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71.
Francesco?Epifano Caroline?Pelucchini Ornelio?Rosati Salvatore?Genovese Massimo?CuriniEmail author 《Catalysis Letters》2011,141(6):844-849
Abstract
An efficient one-pot synthesis of 3,4,5-trisubstituted-3,6-dihydro-2H-1,3-oxazines from acetylene dicarboxylates, aromatic and aliphatic amines, and formaldehyde is described. The six member N,O-heterocyclic nucleus was constructed via Yb(OTf)3 promoted domino hydroamination/Prins reaction/cyclization/dehydration reactions. 相似文献72.
González JM Cusumano A Williams HJ Colazza S Vinson SB 《Journal of chemical ecology》2011,37(6):629-639
Contact kairomones from the host mud dauber wasp Trypoxylon politum Say (Hymenoptera: Crabronidae) that mediate behavioral responses of its ectoparasitoid Melittobia digitata Dahms (Hymenoptera: Eulophidae) were investigated. Chemical residues from host by-products, the cocoon, and the meconium,
induced arrestment behavior of macropterous female parasitoids, while those from the host stage attacked, i.e., the prepupa,
did not. Melittobia digitata response to polar and apolar extracts of host by-products indicated kairomone(s) solubility mainly in hexane. GC and GC/MS
analysis of cocoon and meconium apolar extracts revealed a mixture of linear carboxylic acids from C6 to C18, and both extracts contained almost identical compounds. When a reconstructed blend of host by-product carboxylic acids was
tested, M. digitata females showed only a weak response, thus suggesting that other unidentified compounds present in small quantities also may
be involved. Melittobia digitata’s response to contact kairomones was innate and not affected by previous host exposure experience. Our results provide evidence
of contact kairomone exploitation in the genus Melittobia. The ecological significance of these findings in the host selection process of M. digitata is discussed. 相似文献
73.
Giuseppe Olivieri Antonio Marzocchella Roberto Andreozzi Gabriele Pinto Antonino Pollio 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(6):776-783
BACKGROUND: This paper reports the results of an experimental campaign of autotrophic cultures of Stichococcus strains aiming at selecting the most promising strain for biofuel production. The strain selected—S. bacillaris 158/11—was cultivated in 1 L lab‐scale bubble column photobioreactors under fed‐batch and semi‐continuous conditions. A Bold basal medium supplemented with NaNO3 as nitrogen source was adopted. Tests were carried out at 23 °C, 140 µE m?2 s?1, and air flow rate ranging between 0.4 and 4 vvm. Cultures were characterized in terms of pH, concentration of total nitrogen, total organic carbon, total inorganic carbon, biomass, lipid fraction and methyl‐ester distribution of transesterified lipids. RESULTS: S. bacillaris 158/11 proved to be the best strain to produce biodiesel. Methyl‐ester distribution was characterized by a large fraction of methyl palmitate, methyl linolenate, methyl linoleate, and methyl oleate along with phytol. The process photosynthetic efficiency—fraction of available light stored as chemical energy ‐ was about 1.5%. Specific biomass productivity was ~60 mgDM L?1 day?1 under the semi‐continuous conditions tested. Total lipid productivity was 14 mg L?1 day?1 at a dilution rate of 0.050 L day?1. CONCLUSION: S. bacillaris 158/11 is a potential strain for massive microalgae cultures for biofuel production. Higher biomass/total‐lipid productivity could be obtained in sunlight. Copyright © 2011 Society of Chemical Industry 相似文献
74.
75.
Vitamin E acetate addition to poly(d,l)lactic acid modifies its mechanical behavior without affecting biocompatibility 下载免费PDF全文
Mechanical properties of poly(d,l )lactic acid films enriched with Vitamin E and Vitamin E Acetate (5–40% w/w) were investigated. The addition of both formulations resulted in increased polymer Young's modulus and tensile strength. Human foreskin fibroblasts and murine pre‐osteoblasts were used to assess the biocompatibility of polymers. Pre‐osteoblasts adhesion and proliferation were strongly decreased by Vitamin E, whereas Vitamin E Acetate did not alter cell proliferation. Collagen deposition was lower onto Vitamin E blended polymers than onto native and Vitamin E Acetate blended ones. Fibroblasts adhesion and proliferation were increased by both Vitamin E and Vitamin E Acetate addition. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39970. 相似文献
76.
Antonio Ieni Valeria Barresi Rosario Caltabiano Alessia Caleo Luca Reggiani Bonetti Salvatore Lanzafame Pio Zeppa Rosario Alberto Caruso Giovanni Tuccari 《International journal of molecular sciences》2014,15(12):22331-22341
Background: The assessment of human epidermal growth factor receptor 2 (HER2) gene amplification is essential in order to identify those patients affected by advanced gastric cancer who may benefit from Trastuzumab targeted therapy. Materials and Methods: With the aim to investigate the concordance rate in HER2 status between primary gastric carcinoma (GC) and synchronous lymphnode metastases, we investigated HER2 status in a cohort of 108 surgical formalin-fixed paraffin-embedded specimens of GC and matched synchronous metastatic lymph nodes collected from three different units of Anatomic Pathology in southern of Italy. Fleiss-Cohen weighted k statistics were used to assess the concordance rate of HER2 status. Results: HER2 amplification was observed in 17% of primary GCs and the overall concordance rate with corresponding nodal metastases was 90.74%. Changes in HER2 status between primary GC and matched synchronous metastases were evidenced in 10 (9.26%) cases. Of these, 6 cases were HER2 amplified in the primary GC and not amplified in the metastases, while 4 were HER2 not amplified in the primary tumour and amplified in the lymph node metastases. Conclusions: Although at present the simultaneous determination of HER2 in advanced gastric cancer and corresponding metastatic lymph nodes is not mandatory, the possibility that the synchronous metastases of GC have a different HER2 status from that of the primary tumour is of remarkable significance; Indeed this may have influence on the therapeutic management and prognosis of the patients. 相似文献
77.
Maxime Schwertz Pierre Ranque Sébastien Lemonnier Elodie Barraud Adele Carradò Marie‐France Vallat Michel Nardin 《应用聚合物科学杂志》2015,132(9)
The present study deals with the optimization of polyimide (PI) mechanical properties, obtained by Spark Plasma Sintering (SPS), by using a method combining Design of Experiments (DOE) with physical, structural, and mechanical characterizations. The effects of SPS parameters such as temperature, pressure, dwell time, and cooling rate on the density, mechanical properties, and structure of PI were investigated. The experimental results revealed that the mechanical properties of the material were optimized by raising the sintering temperature up to 350°C. The optimized SPS processing parameters were a temperature of 350°C, a pressure of 40 MPa, and a dwell time of 5 min. Under these conditions, a relative density of 99.6% was reached within only a few minutes. The corresponding mechanical properties consisted of Young's modulus of 3.43 GPa, a Shore D hardness of 87.3, and a compressive strength of 738 MPa for a maximum compressive strain of 61.8%. Moreover, when working at 320°C and at 100 MPa, an increase in the dwell time was necessary to enhance the properties. Contrary to the other parameters, the cooling rate appeared to be a non‐significant parameter. Finally, correlations between the PI structure and the mechanical properties were made to demonstrate the densification mechanisms. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41542. 相似文献
78.
Lucia Marseglia Gabriella D’Angelo Sara Manti Salvatore Aversa Teresa Arrigo Russel J. Reiter Eloisa Gitto 《International journal of molecular sciences》2015,16(1):1209-1220
Exogenous melatonin is used in a number of situations, first and foremost in the treatment of sleep disorders and jet leg. However, the hypnotic, antinociceptive, and anticonvulsant properties of melatonin endow this neurohormone with the profile of a drug that modulates effects of anesthetic agents, supporting its potential use at different stages during anesthetic procedures, in both adults and children. In light of these properties, melatonin has been administered to children undergoing diagnostic procedures requiring sedation or general anesthesia, such as magnetic resonance imaging, auditory brainstem response tests and electroencephalogram. Controversial data support the use of melatonin as anxiolytic and antinociceptive agents in pediatric patients undergoing surgery. The aim of this review was to evaluate available evidence relating to efficacy and safety of melatonin as an analgesic and as a sedative agent in children. Melatonin and its analogs may have a role in antinociceptive therapies and as an alternative to midazolam in premedication of adults and children, although its effectiveness is still controversial and available data are clearly incomplete. 相似文献
79.
Rocco Savino Sergio Paduano Mariaimmacolata Preianò Rosa Terracciano 《International journal of molecular sciences》2012,13(11):13926-13948
In the modern process of drug discovery, clinical, functional and chemical proteomics can converge and integrate synergies. Functional proteomics explores and elucidates the components of pathways and their interactions which, when deregulated, lead to a disease condition. This knowledge allows the design of strategies to target multiple pathways with combinations of pathway-specific drugs, which might increase chances of success and reduce the occurrence of drug resistance. Chemical proteomics, by analyzing the drug interactome, strongly contributes to accelerate the process of new druggable targets discovery. In the research area of clinical proteomics, proteome and peptidome mass spectrometry-profiling of human bodily fluid (plasma, serum, urine and so on), as well as of tissue and of cells, represents a promising tool for novel biomarker and eventually new druggable targets discovery. In the present review we provide a survey of current strategies of functional, chemical and clinical proteomics. Major issues will be presented for proteomic technologies used for the discovery of biomarkers for early disease diagnosis and identification of new drug targets. 相似文献
80.
Jose R. Cabrero‐Antonino Antonio Leyva‐Prez Avelino Corma 《Advanced Synthesis \u0026amp; Catalysis》2012,354(4):678-687
The bis(triflimide)iron(III) salt catalyzes the hydrothiolation of styrenes in a Markovnikov fashion with good selectivities and high yields. After isolation, different benzylic thioethers are obtained. This iron(III) catalyst is unique in terms of regioselectivity and represents a sustainable and economic alternative to those processes based on stoichiometric reagents. 相似文献