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排序方式: 共有1005条查询结果,搜索用时 656 毫秒
91.
Chiara Tognoli Marco Saroglia Genciana Terova Rosalba Gornati Giovanni Bernardini 《Food chemistry》2011
The 5S ribosomal RNA is a very suitable target for easy, rapid and inexpensive fish species identification due to its structure, consisting of a conserved region followed by a species-specific noncoding region called ‘nontranscribed spacer’. We have exploited this species-specificity in length and sequence to discriminate among fish species which can be subjected to substitution in the fish markets. After sequencing and alignment of the corresponding portions of the 5S rRNAs of different fish species, we have designed the primer pairs necessary for PCR amplification on the DNA traits which most diverged and a primer pair on conserved regions. Our results have shown the feasibility, simplicity and reliability of the proposed approach for the detection of mislabelling or fraudulent substitution of fish species. 相似文献
92.
Fabio Maria Sabbatini Dr. Romano Di Fabio Dr. Mauro Corsi Dr. Paolo Cavanni Dr. Steve M. Bromidge Dr. Yves St‐Denis Dr. Lucilla D'Adamo Dr. Marilisa Rinaldi Dr. Chiara Savoia Dr. Claudia Mundi Dr. Benedetta Perini Dr. Andrew J. Carpenter Dr. Giovanna Dal Forno Dr. Federico Faggioni Dr. Michela Tessari Dr. Francesca Pavone Dr. Alberto Buson Dr. Mario Mattioli Dr. Elisabetta Perdona' Dr. Sergio Melotto Dr. 《ChemMedChem》2010,5(9):1450-1455
93.
Vincenzo Calemma Chiara Gambaro Wallace O. Parker Rosa Carbone Roberto Giardino Pietro Scorletti 《Catalysis Today》2010,149(1-2):40-46
A light cobalt catalyzed Fischer–Tropsch (FT) wax was subjected to hydrocracking in the range of temperature 319–351 °C and hydrogen pressure between 3.5 and 6.0 MPa. The catalyst used was platinum on amorphous silica–alumina. Hydrocracking reaction led to an increase of middle distillate yield up to 85% with a contemporary increase of iso-paraffins concentration which resulted in a remarkable improvement of cold flow properties of the products. The freezing point of C10–C14 fraction passed from ?23 to ?45 °C while the pour point of C15–C22 fraction decreased from 13 to ?23 °C. The latter fraction displayed high cetane numbers ranging between 75 and 80. Changes in carbon distribution and molecular structure of products during hydrocracking have been rationalized in the light of the accepted hydrocracking mechanism where n-paraffins undergo to consecutive isomerization reactions leading to isomers with progressively higher branching degree and concomitant cracking reaction. Experimental evidences support the view that apparent reactivity of n-paraffins is chain length dependent, increasing with the molecular weight. Detailed characterization by NMR and GC showed that branching groups abundance in the middle distillate products was the following: methyl ? ethyl > propyl.Emission tests carried out with FT diesel and commercial ultra low sulfur diesel showed that FT diesel has excellent combustion properties and leads to a reduction of emissions. 相似文献
94.
Chiara Cavaliere Patrizia Foglia Chiara Guarino Mario Motto Manuela Nazzari Roberto Samperi Aldo Laganà Nicola Berardo 《Food chemistry》2007,105(2):700-710
A confirmatory method for fusariotoxin analysis in maize meal, based on liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS), was developed, and compared with a previously published screening method, based on the same technique. By eluting selectively from a Carbograph-4 clean-up cartridge trichothecenes, fumonisins and macrocyclic lactones, and optimizing LC–MS/MS conditions for every chemical class, a sensitive and reliable determination was performed. Method quantification limits for confirmatory and screening methods were in the range 0.001–0.019 mg/kg and 0.003–0.125 mg/kg, respectively. 相似文献
95.
M Barbero R Enria M Pagliano M Canni P Nicolaci U Bertini F Bocci C Bocci G Chiara 《Canadian Metallurgical Quarterly》1997,49(11):491-497
BACKGROUND: The aim of this study was to determine the diagnostic value of hysteroscopy and transvaginal ultrasonography in patients with abnormal uterine bleeding (AUB) in the peri and postmenopausal period. METHODS: 302 patients with AUB, underwent hysteroscopy and in 86 cases, also a transvaginal ultrasonography before hysteroscopy was performed. Results were compared with the histological diagnosis. RESULTS: The diagnostic accuracy of hysteroscopy was very high in the cases of endometrial carcinoma (sensibility 100%, specificity 99%), and lower in the cases of endometrial hyperplasia (sensibility 69%, specificity 72%) and endometrial atrophy (sensibility 29% and specificity 97%). Sonography proved to be less reliable in the diagnosis of endometrial pathology (carcinoma: sensibility 57%, specificity 100%, hyperplasia: sensibility 62.5% specificity 63%). The results of this study show that sonography may be used as a first choice diagnostic test in the investigation of women with AUB. CONCLUSIONS: Hysteroscopy represent a second diagnostic step for achieving a proper histologic diagnosis. 相似文献
96.
Mariya Aloshyna Begoa Milin Medina Lars Poulsen Juliette Moreau David Beljonne Jrme Cornil Giuseppe Di Silvestro Michele Cerminara Francesco Meinardi Riccardo Tubino Heiner Detert Sigurd Schrader Hans‐Joachim Egelhaaf Chiara Botta Johannes Gierschner 《Advanced functional materials》2008,18(6):915-921
Perhydrotriphenylene‐based channel‐forming inclusion compounds (ICs) and thin films made of polyphenylenevinylene (PPV)‐type oligomers with terminal alkoxy groups are investigated and compared in a combined experimental and theoretical approach. Interchromophore interactions and host‐guest interactions are elucidated by UV/Vis and Raman spectroscopy. The impact of the local environment of the chromophore on the optical and photophysical properties is discussed in light of quantum‐chemical calculations. In stark contrast to thin films where preferential side‐by‐side orientation leads to quenching of photoluminescence (PL) via non‐emissive traps, the ICs are found to be attractive materials for opto‐electronic applications: they offer high chromophore concentrations, but at the same time behave as quasi‐isolated entities of tightly packed, well‐oriented objects with high PL quantum yields and the possibility of color tuning. 相似文献
97.
The preparation and characterization of oligothienylene dialdehydes and related soluble copolymers in which thenylenic segments regularly alternate with phenylenic portions linked by azomethine moieties is presented. The polymer series with three, six and eight thienylenic residues showed interesting evidences of electronic confinement in low-gap segments (thienylenic). Self-assembled structures of oligomers can be obtained either by evaporation in high vacuum or by a proper thermal treatment of spin coated films, depending on the molecule length. Polymers prepared by different synthetic routes show different thermal and structural properties as a function of the ratio of two possible isomers at imino linkage. The order degree also influences the optical properties in fact luminescence data are strictly related to the percentage of the two isomers. 相似文献
98.
Gold(III) complexes constitute a new class of metallodrugs, of potential interest for cancer treatment. During the past decade
different kinds of gold(III) complexes have been reported to be appreciably stable under physiological-like conditions and
to manifest relevant antiproliferative properties against selected human tumor cell lines. Some relevant examples are presented.
Recent investigations point out that the interactions of cytotoxic gold(III) complexes with DNA are significantly different
and weaker than those of platinum analogues; important interactions with model proteins and target proteins have been reported
as well. Accordingly, the mechanisms of action of cytotoxic gold(III) complexes seem to be innovative and substantially different
from that of cisplatin. Relevant antimitochondrial effects were demonstrated in some cases, eventually leading to cell apoptosis. 相似文献
99.
Laura Mayol Daniela De Stefano Virginia Campani Francesca De Falco Eleonora Ferrari Claudia Cencetti Pietro Matricardi Luigi Maiuri Rosa Carnuccio Angela Gallo Maria Chiara Maiuri Giuseppe De Rosa 《Journal of materials science. Materials in medicine》2014,25(6):1483-1493
In this study, a sterile and biocompatible chitosan (CHI) gel for wound healing applications was formulated. CHI powder was treated in autoclave (ttCHI) to prepare sterile formulations. The heat treatment modified the CHI molecular weight, as evidenced by GPC analysis, and its physical–chemical features. Differential scanning calorimetry studies indicated that the macromolecules, before and after thermal treatment, differ in the strength of water-polymer interaction leading to different viscoelastic and flow properties. Thermally treated CHI exhibited the following effects: (i) increased the proliferation and migration of human foreskin foetal fibroblasts at 24 h; (ii) accelerated wound healing (measured as area of lesion) at 3 and 10 days in an in vivo model of pressure ulcers. These effects were linked to the increase of the hydroxyproline and haemoglobin content as well as Wnt protein expression. Moreover, we found a reduction of myeloperoxidase activity and TNF-α mRNA expression. These observations suggest the potential of this novel CHI gel in wound healing and other therapeutic applications. 相似文献
100.
Mukherjee S Gualandi C Focarete ML Ravichandran R Venugopal JR Raghunath M Ramakrishna S 《Journal of materials science. Materials in medicine》2011,22(7):1689-1699
In myocardial tissue engineering the use of synthetically bioengineered flexible patches implanted in the infarcted area is
considered one of the promising strategy for cardiac repair. In this work the potentialities of a biomimetic electrospun scaffold
made of a commercial copolymer of (l)-lactic acid with trimethylene carbonate (P(l)LA-co-TMC) are investigated in comparison to electrospun poly(l)lactic acid. The P(l)LA-co-TMC scaffold used in this work is a glassy rigid material at room temperature while it is a rubbery soft material at 37°C.
Mechanical characterization results (tensile stress–strain and creep-recovery measurements) show that at 37°C electrospun
P(l)LA-co-TMC displays an elastic modulus of around 20 MPa and the ability to completely recover up to 10% of deformation. Cell culture
experiments show that P(l)LA-co-TMC scaffold promotes cardiomyocyte proliferation and efficiently preserve cell morphology, without hampering expression
of sarcomeric alpha actinin marker, thus demonstrating its potentialities as synthetic biomaterial for myocardial tissue engineering. 相似文献