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1.
Kučinskaitė Agnė Pobłocka-Olech Loretta Krauze-Baranowska Mirosława Briedis Vitalis Savickas Aruñas Sznitowska Małgorzata 《平面色谱法杂志一现代薄层色谱法》2007,20(2):121-125
SPE and TLC have been used for qualitative and quantitative analysis of salidroside, rosavin, rosarin, and rosin in commercially available dry extracts from Rhodiola rosea roots. The best separation of all the compounds was achieved on silica gel TLC plates with ethyl acetate—methanol—water, 77 + 13 + 10 (v/v), as mobile phase. UV detection was performed at λ = 215 nm for salidroside and at λ= 245 nm for the rosavins (rosavin, rosarin, and rosin). Detection limits for salidroside and the rosavins were 90 ng and 60 ng per spot, respectively. Results from quantitative analysis confirmed the manufacturer’s declaration of the amounts of salidroside and the rosavins in the extracts.
相似文献2.
Alessandra Celletti Piero Negrini 《NoDEA : Nonlinear Differential Equations and Applications》1994,1(4):313-322
We consider a Lagrangian Differential System (L.D.S.) with Lagrangian function L(q,
)=T(q,
)+U(q), sufficiently smooth in a neighbourhood of the critical pointq=0 of the potential functionU(q). The kinetic function T(q,
) is a non homogeneous quadratic function of the
's, i.e. the L.D.S. contains the so-called gyroscopic forces. The potential functionU(q) starts with a degenerate (but non zero), semidefinite-negative, quadratic form. Moreover,q=0 is not a proper maximum ofU, and this property has to be recognized in a suitable way. By analizing the problem of the existence of solutions of the L.D.S., which asymptotically tend to the equilibrium solution, (q,
)=(0,0), we provide a sufficient criterium for its instability.Work performed under the auspices of M.U.R.S.T. (Ministero dell'Universitá e della Ricerca Scientifica e Tecnologica) and G.N.F.M. (Gruppo Nazionale di Fisica Matematica of the National Research Council (C.N.R.)). 相似文献
3.
Even with the emergence of advanced techniques of separation and identification, it is rarely possible to analyse food without manipulation. The traditional techniques for sample preparation are time consuming and require large amount of reagents, which are expensive, generate considerable waste, contaminate the sample and can enrich it for analytes. The more analytical techniques have become highly developed, the more has sample clean-up become important in order to fully take advantage of them. Due to the multiplicity of food matrices, it is not possible to use one sample preparation technique, so many methods have been proposed for meeting all the requirements. The newest variations of wet digestion, solvent and sorbent extraction and membrane separation are summarised and their most recent applications to food analysis are provided. 相似文献
4.
Migas Piotr Heyka Magdalena Pobłocka-Olech Loretta Krauze-Baranowska Mirosława 《平面色谱法杂志一现代薄层色谱法》2012,25(5):439-444
JPC – Journal of Planar Chromatography – Modern TLC - Three step bivariant multiple development thin-layer chromatography (BMD-TLC) technique was used in the quantitative analysis of... 相似文献
5.
Federica Sodano Elena Gazzano Roberta Fruttero Loretta Lazzarato 《Molecules (Basel, Switzerland)》2022,27(7)
Nitric oxide is a ubiquitous signaling radical that influences critical body functions. Its importance in the cardiovascular system and the innate immune response to bacterial and viral infections has been extensively investigated. The overproduction of NO is an early component of viral infections, including those affecting the respiratory tract. The production of high levels of NO is due to the overexpression of NO biosynthesis by inducible NO synthase (iNOS), which is involved in viral clearance. The development of NO-based antiviral therapies, particularly gaseous NO inhalation and NO-donors, has proven to be an excellent antiviral therapeutic strategy. The aim of this review is to systematically examine the multiple research studies that have been carried out to elucidate the role of NO in viral infections and to comprehensively describe the NO-based antiviral strategies that have been developed thus far. Particular attention has been paid to the potential mechanisms of NO and its clinical use in the prevention and therapy of COVID-19. 相似文献
6.
F. Ambrosino F. Anulli D. Babusci S. Bianco C. Bini N. Brambilla R. De Sangro P. Gauzzi P.M. Gensini S. Giovannella V. Muccifora M. Negrini F. Nguyen S. Pacetti G. Pancheri M. Passera A. Passeri A.D. Polosa M. Radici Y.N. Srivastava A. Vairo G. Venanzoni G. Violini 《The European Physical Journal C - Particles and Fields》2007,50(3):729-768
We present a detailed study, done in the framework of the INFN 2006 Roadmap, of the prospects for e+e- physics at the Frascati National Laboratories. The physics case for an e+e- collider running at high luminosity at the φ resonance energy and also reaching a maximum center of mass energy of 2.5 GeV
is discussed, together with the specific aspects of a very high luminosity τ-charm factory. Subjects connected to kaon decay
physics are not discussed here, being part of another INFN Roadmap working group. The significance of the project and the
impact on INFN are also discussed. All the documentation related to the activities of the working group can be found in http://www.roma1.infn.it/people/bini/roadmap.html. 相似文献
7.
Sparzak Barbara Krauze-Baranowska Mirosława Pobłocka-Olech Loretta 《平面色谱法杂志一现代薄层色谱法》2008,21(2):103-106
JPC – Journal of Planar Chromatography – Modern TLC - Densitometric HPTLC has been used for determination of catechins in shoot and callus cultures of two species from the genus... 相似文献
8.
9.
Reale S Fasciani P Pace L De Angelis F Marcozzi G 《Rapid communications in mass spectrometry : RCM》2011,25(17):2511-2516
The cultivar Anamed (A3) is a hybrid of Artemisia annua with a high content of the secondary metabolite artemisinin, a well-known antimalarial drug. Here we report for the first time the volatile profile of fresh leaves of this hybrid in comparison with that of Artemisia annua L. wild-type species. Evaluation and comparison of the volatile profiles of A. annua genotypes with different content in artemisinin were carried out by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) that was performed on fresh leaves of the plants under investigation using a polydimethylsiloxane (PDMS) fiber. The chromatograms obtained from hybrids with a high content of artemisinin (A. annua cv. Anamed A3 and A. annua cv. Artemis F2) reveal the total absence of artemisia ketone, one of the major and characteristic compounds of the wild-type A. annua L., along with a significantly lower variety of volatile compounds. In conclusion, HS-SPME coupled with GC/MS is a very useful, non-destructive and efficient method to describe the volatile pattern of Artemisia annua cultivars. It represents a rapid screening method for the evaluation of volatile biomarkers like artemisia ketone, whose absence is typical of artemisinin-rich A. annua cultivars. 相似文献
10.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献