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71.
CAGLIARI-PADOVA-TORINO Collaboration L. Cugusi M.P. Macciotta S. Marcello A. Masoni G. Puddu A. Raimondi S. Serci M.T. Sergi M. Agnello F. Iazzi B. Minetti T. Bressani A. Feliciello A. Musso R. Cherubini F. Gramegna M. Morandin J. Lichtenstadt 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1988,270(2-3):354-360
The operating performances of a low-momentum (< 270 MeV/c) tagged
beam are reported. The
beam is obtained by means of the charge exchange reaction
n on a liquid hydrogen target. The neutron associated to the
in the two-body reaction is used for the determination of the
energy and direction. The measured total rate of tagged
is 8.02 ± 0.03 × 10−5 per incident
at 300 MeV/c. 相似文献
72.
<Emphasis Type="Italic">Arabidopsis thaliana:</Emphasis> A New Test Species for Phytotoxic Bioassays 总被引:1,自引:0,他引:1
Lettuce seeds (Lactuca sativa L.) and other crop species are often used in phytotoxic bioassays that are designed to detect allelochemicals. The seeds of these species are considered ideal because they are readily available, germinate rapidly and uniformly, and are routinely used in laboratories around the world. Despite their common use, however, the seeds of these species are often not as sensitive or responsive to some phytotoxic chemicals as are the seeds of other species. While searching for a more sensitive test species for phytotoxic bioassays, the Columbia ecotype of Arabidopsis thaliana exhibited greater sensitivity to seven potent allelochemicals than did lettuce seeds, which, in some cases, did not respond at all to those substances. Sensitivity satisfies one of the criteria for selecting a test species for bioassays. We now report on the results of our study and offer additional reasons for using A. thaliana seeds. 相似文献
73.
Scherm B Palomba M Serra D Marcello A Migheli Q 《International journal of food microbiology》2005,98(2):201-210
74.
Patrizia Casero Marcello Duranti Paolo Cerletti 《Journal of the science of food and agriculture》1983,34(10):1113-1116
The subunit compositions of a legumin-like (globulin 8) and a vicilin-like protein (globulin 4) extracted from a plurality of seeds and from a single seed both in commercial and in a selected cultivar of Lupinus albus were studied. In the case of globulin 4, a very similar number of bands were observed in SDS-PAGE, in the protein extracted from a batch of seed and in the same globulin isolated from a single seed. For globulin 8 the SDS-PAGE pattern showed fewer subunits in the protein from the batch of seeds than in that from a single seed. This is more pronounced in the single seed and in the plurality of seeds of a selected cultivar. Reasons for this behaviour are discussed. 相似文献
75.
Arildo José Braz de Oliveira Regina Aparecida Correia Gonçalves Talita Perez Cantuaria Chierrito Marcelo Müller dos Santos Lauro Mera de Souza Philip Albert James Gorin Guilherme Lanzi Sassaki Marcello Iacomini 《Food chemistry》2011
Fructooligosaccharides have been isolated from roots and leaves of Stevia rebaudiana, by hot aqueous extraction, followed by precipitation with ethanol. Their structure has been determined using methylation and NMR analysis, MALDI-TOF, and ESI-MS. Fructooligosaccharides contained almost exclusively (2→1)-linked β-fructofuranosyl, with terminal α-glucopyranosyl and β-fructofuranosyl units. MALDI-TOF and ESI-MS analyses showed the wide range of degree of polymerisation (DP) present in various extracts. From roots and leaves, three different fractions gave profiles of homologous series, with DPs ranging up to 17 with MALDI-TOF and 19 using ESI-MS. These inulin-type fructooligosaccharides were the major component of extracts from S. rebaudiana roots and significant components from the leaves. 相似文献
76.
Giulio Verna Marina Liso Elisabetta Cavalcanti Giusy Bianco Veronica Di Sarno Angelo Santino Pietro Campiglia Marcello Chieppa 《International journal of molecular sciences》2021,22(15)
Dendritic cells (DCs) can be divided by lineage into myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs). They both are present in mucosal tissues and regulate the immune response by secreting chemokines and cytokines. Inflammatory bowel diseases (IBDs) are characterized by a leaky intestinal barrier and the consequent translocation of bacterial lipopolysaccharide (LPS) to the basolateral side. This results in DCs activation, but the response of pDCs is still poorly characterized. In the present study, we compared mDCs and pDCs responses to LPS administration. We present a broad panel of DCs secreted factors, including cytokines, chemokines, and growth factors. Our recent studies demonstrated the anti-inflammatory effects of quercetin administration, but to date, there is no evidence about quercetin’s effects on pDCs. The results of the present study demonstrate that pDCs can respond to LPS and that quercetin exposure modulates soluble factors release through the same molecular pathway used by mDCs (Slpi, Hmox1, and AP-1). 相似文献
77.
Dibakar Sarkar Dr. Ipsita Chakraborty Marcello Condorelli Baijayanti Ghosh Thorben Mass Dr. Markus Weingarth Dr. Atin K Mandal Prof. Carmelo La Rosa Dr. Vivekanandan Subramanian Dr. Anirban Bhunia 《ChemMedChem》2020,15(3):293-301
The three GxxxG repeating motifs from the C-terminal region of β-amyloid (Aβ) peptide play a significant role in regulating the aggregation kinetics of the peptide. Mutation of these glycine residues to leucine greatly accelerates the fibrillation process but generates a varied toxicity profile. Using an array of biophysical techniques, we demonstrated the uniqueness of the composite glycine residues in these structural repeats. We used solvent relaxation NMR spectroscopy to investigate the role played by the surrounding water molecules in determining the corresponding aggregation pathway. Notably, the conformational changes induced by Gly33 and Gly37 mutations result in significantly decreased toxicity in a neuronal cell line. Our results indicate that G33xxxG37 is the primary motif responsible for Aβ neurotoxicity, hence providing a direct structure–function correlation. Targeting this motif, therefore, can be a promising strategy to prevent neuronal cell death associated with Alzheimer's and other related diseases, such as type II diabetes and Parkinson's. 相似文献
78.
Dr. André L. C. S. Nascimento Richard P. Fernandes Christian Quijia Victor H. S. Araujo Juliana Pereira Prof. Dr. Jerusa S. Garcia Prof. Dr. Marcello G. Trevisan Prof. Dr. Marlus Chorilli 《ChemMedChem》2020,15(12):1018-1029
Since the beginning of the HIV epidemic, research has been carried out to control the virus. Understanding the mechanisms of replication has given access to the various classes of drugs that over time have transformed AIDS into a manageable chronic disease. The class of protease inhibitors (PIs) gained notice in anti-retroviral therapy, once it was found that peptidomimetic molecules act by blocking the active catalytic center of the aspartic protease, which is directly related to HIV maturation. However, mutations in enzymatic internal residues are the biggest issue for these drugs, because a small change in biochemical interaction can generate resistance. Low plasma concentrations of PIs favor viral natural selection; high concentrations can inhibit even partially resistant enzymes. Food-drug/drug-drug interactions can decrease the bioavailability of PIs and are related to many side effects. Therefore, this review summarizes the pharmacokinetic properties of current PIs, the changes when pharmacological boosters are used and also lists the major mutations to help understanding of how long the continuous treatment can ensure a low viral load in patients. 相似文献
79.
80.
Gianvito Difilippo Maria Pia Fanti Agostino Marcello Mangini 《IEEE/CAA Journal of Automatica Sinica》2022,9(2):259-269
The paper deals with the consensus problem in a leaderless network of agents that have to reach a common velocity while forming a uniformly spaced string. Moreover, the final common velocity (reference velocity) is determined by the agents in a distributed and leaderless way. Then, the consensus protocol parameters are optimized for networks characterized by a communication topology described by a class of directed graphs having a directed spanning tree, in order to maximize the convergence rate and avoid oscillations. The advantages of the optimized consensus protocol are enlightened by some simulation results and comparison with a protocol proposed in the related literature. The presented protocol can be applied to coordinate agents such as mobile robots, automated guided vehicles (AGVs) and autonomous vehicles that have to move with the same velocity and a common inter-space gap. 相似文献