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1.
Aronov PA Hall LM Dettmer K Stephensen CB Hammock BD 《Analytical and bioanalytical chemistry》2008,391(5):1917-1930
Biologically active forms of vitamin D are important analytical targets in both research and clinical practice. The current
technology is such that each of the vitamin D metabolites is usually analyzed by individual assay. However, current LC-MS
technologies allow the simultaneous metabolic profiling of entire biochemical pathways. The impediment to the metabolic profiling
of vitamin D metabolites is the low level of 1α,25-dihydroxyvitamin D3 in human serum (15–60 pg/mL). Here, we demonstrate that liquid–liquid or solid-phase extraction of vitamin D metabolites
in combination with Diels–Alder derivatization with the commercially available reagent 4-phenyl-1,2,4-triazoline-3,5-dione
(PTAD) followed by ultra-performance liquid chromatography (UPLC)–electrospray/tandem mass spectrometry analysis provides
rapid and simultaneous quantification of 1α,25-dihydroxyvitamin D3, 1α,25-dihydroxyvitamin D2, 24R,25-dihydroxyvitamin D3, 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 in 0.5 mL human serum at a lower limit of quantification of 25 pg/mL. Precision ranged from 1.6–4.8 % and 5–16 % for 25-hydroxyvitamin
D3 and 1α,25-dihydroxyvitamin D3, respectively, using solid-phase extraction.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
Simone Schiesel Michael Lämmerhofer Wolfgang Lindner 《Analytical and bioanalytical chemistry》2010,396(5):1655-1679
The presented work deals with the development and comprehensive validation of a quantitative LC–electrospray ionization (ESI)–tandem
mass spectrometry (MS/MS) method using a triple quadrupole instrument in the MRM mode for the metabolic profiling of amino
acids, organic acids, vitamins, some biogenic amines, secondary metabolites of β-lactam antibiotics biosynthesis as well as
their intermediates, and degradation products in fermentation broths of β-lactam antibiotics production (in total 57 hydrophilic
compounds). A great number of chromatographic systems (22 different stationary phase/mobile phase conditions) were screened
for their adequate chromatographic selectivity to cope with isobaric compounds and other critical analyte pairs. Finally,
a hydrophilic interaction liquid chromatography (HILIC) method employing a zwitterionic ZIC-HILIC column was selected as best
compromise. Particular focus was given on the elucidation of absolute and relative matrix effects via comparison of slopes
of calibration functions of spiked matrix and standard solutions. These data as well as precision and accuracy data confirm
suitability of the HILIC–ESI–MS/MS assay for metabolic profiling studies in fermentation samples. Detailed comprehensive data
sets are presented which should illustrate critical issues, problems, and challenges of multitarget quantitative metabolic
profiling and should outline possible strategies to circumvent pitfalls and overcome common problems. 相似文献
3.
Fábio C. Sampaio Paolo Torre Flávia M. Lopes Passos Célia Alencar de Moraes Patrizia Perego Attilio Converti 《Applied biochemistry and biotechnology》2007,136(2):165-181
To obtain in-depth information on the overall metabolic behavior of the new good xylitol producer Debaryomyces hansenii UFV-170, batch bioconversions were carried out using semisynthetic media with compositions simulating those of typical acidic
hemicellulose hydrolysates of sugarcane bagasse. For this purpose, we used media containing glucose (4.3–6.5 g/L), xylose
(60.1–92.1 g/L), or arabinose (5.9–9.2 g/L), or binary or ternary mixtures of them in either the presence or absence of typical
inhibitors of acidic hydrolysates, such as furfural (1.0–5.0 g/L), hydroxymethylfurfural (0.01–0.30 g/L), acetic acid (0.5–3.0
g/L), and vanillin (0.5–3.0 g/L). D. hansenii exhibited a good tolerance to high sugar concentrations as well as to the presence of inhibiting compounds in the fermentation
media. It was able to produce xylitol only from xylose, arabitol from arabinose, and no glucitol from glucose. Arabinose metabolization
was incomplete, while ethanol was mainly produced from glucose and, to a lesser less extent, from xylose and arabinose. The
results suggest potential application of this strain in xyloseto-xylitol bioconversion from complex xylose media from lignocellulosic
materials. 相似文献
4.
Tatyana S. Baptista Marcelo M. Redígolo Cibele B. Zamboni Ivone M. Sato Jose R. Marcelino 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):399-403
The World Health Organization states that envenomation is responsible for a high number of deaths per year, especially in
equatorial areas. The only effective specific treatment is the use of hyperimmune serum (antivenom). In Brazil, Crioula breed
horses are used for antivenom production, with great importance in the maintenance of public health programs. A strict biochemical
and metabolic control is required to attain specificity in antiserum. Inorganic elements represent only a small fraction of
whole blood. Nonetheless, they play important roles in mammalian metabolism, being responsible for controlling enzymatic reactions,
respiratory and cardiac functions and ageing. In this work, whole blood samples from Crioula breed horses were analyzed by
EDXRF technique. The reference interval values were determined for the elements Na (1955–2013 μg g−1), Mg (51–75 μg g−1), P (523–555 μg g−1), S (1628–1730 μg g−1), Cl (2388–2574 μg g−1), K (1649–1852 μg g−1), Ca (202–213 μg g−1), Cu (4.1–4.5 μg g−1) and Zn (2.4–2.8 μg g−1) and a comparative study with NAA results was outlined. The samples were obtained from Instituto Butantan. Both techniques
showed to be appropriate for whole blood sample analyses and offer a new perspective in Veterinary Medicine. 相似文献
5.
Summary Colloidal plasma substitutes of chemically modified starch are used in surgery and in emergency medicine. Acetyl starch (ACS)
is a new plasma substitute based on an amylopectin acetic ester. Metabolic cleavage of the ACS ester substituents leads to
improved degradation and elimination of infused polymer. To determine the metabolic fate of ACS a rapid LC-method for ACS
quantitiation in blood samples was needed. For this purpose a size-exclusion chromatography (SEC) system with improved sensitivity
is outlined using a refractive index detector. The limit of detection is 0.005 mg mL−1. From 0.10–5.00 mg mL−1 a linear relationship (correlation coefficient R=0,9999) between the RI signal and ACS concentration is obtained. Recoveries
of ACS from blood plasma range 102.3–107.7% for ACS 200/0.5 (range 0.20–7.94 mg mL−1) and 103.0–111.4% for ACS 200/0.7 (range 0.19–9.33 mg mL−1). Only small differences between runs are obtained. In the inter assay test coeficients of variation of 1.8% and of 2.6%
respectively are obtained for ACS 200/0.5 and ACS 200/0.7. 相似文献
6.
Li C Wen D Zhang J Chen Z Cong W Rao Z Liu H 《Analytical and bioanalytical chemistry》2006,386(7-8):1985-1993
Metabolism of four tobacco-specific N-nitrosamines (TSNAs), N′-nitrosonornicotine (NNN), N′-nitrosoanatabine (NAT), N′-nitrosoanabasine (NAB), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) has been studied by solid-phase extraction
(SPE) and liquid chromatography–tandem mass spectrometry (LC–MS–MS). 4-(Methylnitrosamino)-4-(3-pyridyl)-1-butanol (iso-NNAL)
was used as internal standard. SPE and LC–MS–MS was found to be a rapid, simple, sensitive, and selective method for analysis
of TSNAs in rabbit serum. The relative standard deviation (R.S.D., n = 6) for analysis of 5 ng mL−1 and 0.5 ng mL−1 standards and of serum sample spiked with 5 ng mL−1 standards of five TSNAs was 2.1–11% and recovery of 5 ng mL−1 standards from serum was 100.2–112.9%. A good linear relationship was obtained between peak area ratio and concentration
in the range of 0.2–100 ng mL−1 for NNAL and 0.5–100 ng mL−1 for other four TSNAs, with correlation coefficients (R
2) >0.99 (both linear and log–log regression). Detection limits for standards in solvent were between 0.04 and 0.10 ng mL−1. Doses of TSNAs administered to rabbits via the auricular vein were 4.67 μg kg−1 and 11.67 μg kg−1, in accordance with the different levels in cigarettes. Metabolic curves were obtained for the four TSNAs and for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol
(NNAL), a metabolite of NNK; on the basis of these curves we modeled metabolic kinetic equations for these TSNAs by nonlinear
curve fitting. 相似文献
7.
V. I. Podolska L. N. Yakubenko Z. R. Ulberg V. N. Ermakov N. I. Grischenko 《Colloid Journal》2010,72(6):830-836
The effect of weak pulse electric fields on the destructive activity and surface properties of Pseudomonas bacteria is studied. It is revealed that the physiological response of bacteria on their treatment by external pulse fields
depends on field parameters and is accompanied by the changes in the values of electrokinetic potential and hydrophobicity.
The treatment of bacteria by the electric field with pulse duration of 1–10 ms and frequency of 100–500 Hz tends to increase
by 20–30% the destruction of NaAg(CN)2. It is suggested that changes in surface properties and the enhancement of biochemical activity of bacteria are based on
the metabolic reaction of the cell related to the stimulation or suppression of the bacteria respiration upon the imposition
of external field. 相似文献
8.
Biomethanation of leaves of the legumeL. leucocephala operated in batch reactors at different input volatile solids (12–18 g/L) proceeded in distinct metabolic phases. An initial
cellulolytic phase of 4 d was followed by an early and active methanogenic phases (5–21 d) and a terminal phase of low-rate
methanogenesis. Hydrolysis of cellulose was concentration-dependent and resulted in increased volatile acid levels. The trend
of changes showed some variations at different input volatile solids. The changes in the levels of volatile acids followed
an oscillatory pattern. The controlled rate of cellulose hydrolysis, levels of volatile acids, and steady-state levels of
soluble carbohydrates and reducing sugars observed during active methanogenesis are indicative of interactive metabolic regulations. 相似文献
9.
Shen Xuesong Wang Tao Jin Meihua Zhao Chunxia Qin Xuelian Liu Hanfu Qiu Zhuangping Liu Yi 《Journal of Thermal Analysis and Calorimetry》2012,107(3):1307-1313
A thermal dynamic model of nanoformulations entrapped in artesunate liposomes was established and biological thermodynamics
was applied for investigation of the drug formulations. Effects of artesunate liposomes on the growth metabolism of Escherichia coli were studied by microcalorimetry. The results showed that (1) Comparison of artesunate and artesunate liposomes, the thermogenesis
curves of E. coli were significant different in the metabolic process: lag phase (AB), log phase (BC), stationary phase (CD), and decline phase
(DE); (2) Linear fit of the data of total metabolic heat of E. coli effected by different concentration artesunate (1–300 μg), the equation can be obtained as follows: Y = 364720.61−1075.25x, R = 0.9985; Linear fit of the data of total metabolic heat of E. coli effected by different concentration artesunate liposomes (30–120 μg), the linear equation can be obtained as follows: Y = 54251.5765−35.71122x, R = 0.98345; (3) The half inhibitory concentration I
C50 was 50.05 μg/mL, the relative sensitivity was obviously different; (4) Artesunate liposomes having better sustained release
properties as compare to artesunate. 相似文献
10.
An ideal toxicity assay should utilize multiple indexes obtained from transient changes of metabolic activities. Here, we
demonstrate the possibility for a novel toxicity bioassay using the damped glycolytic oscillation phenomenon occurring in
starved yeast cells. In a previous study, the phenomenon was characterized in detail. Under optimum conditions to induce the
phenomenon, the wave shapes of the damped glycolytic oscillations were changed by the instantaneous addition of both glucose
and chemicals and by changing the chemical concentration. We estimated the changes in the oscillation wave shapes as six indexes,
i.e., the number of wave cycles, maximum amplitude, oscillation frequency, attenuation coefficient, initial peak height, and
non-steady-state time. These index changes were obtained from several kinds of chemicals. The chemicals, especially those
for acids (0.01–100 mM HCl and 0.01–50 mM citric acid), bases (0.001–50 mM KOH), heavy metal ions (1–1,000 mg L−1; Cu2+, Pb2+, Cd2+, Hg2+), respiratory inhibitors (3–500 mg L−1 NaN3), dissolved oxygen removers (10–300 mg L−1 NaSO3), surfactants (10–200 mg L−1 benzalkonium chloride), and aldehyde (10–1,000 mg L−1 acetaldehyde), showed characteristic patterns depending on each chemical and its concentration. These significant results
demonstrate the possibilities of new methods for both toxicity qualification and quantification.
Figure Influences of surfactant on the oscillation wave shape
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
Thevis M Sigmund G Gougoulidis V Beuck S Schlörer N Thomas A Kwiatkowska D Pokrywka A Schänzer W 《Analytical and bioanalytical chemistry》2011,401(2):543-551
Benfluorex [1-(m-trifluoromethylphenyl)-2-(β-benzoyloxyethyl)aminopropane] has been widely used for the treatment of atherogenic metabolic
disorders and impaired carbohydrate metabolism (particularly in obese type-II diabetic patients) as well as an anorectic drug.
Due to its potentially performance-enhancing properties, benfluorex has been added to the list of prohibited compounds and
methods of doping by the World Anti-Doping Agency (WADA) in 2010, necessitating the implementation of the drug as well as
its major metabolites into routine doping control procedures. In the present study, human urinary metabolites of benfluorex
were characterized by gas chromatography–electron ionization–mass spectrometry (GC-EI-MS) as well as liquid chromatography–electrospray
ionization–high resolution/high accuracy tandem mass spectrometry (LC-ESI-MS/MS). Commonly employed sports drug testing approaches
consisting of liquid–liquid extraction followed by GC-MS or urine dilution and immediate LC-MS/MS analysis were expanded and
validated with regard to specificity, recovery (48–54%, GC-MS only), intra- and interday precision (<25%), limits of detection
(5–8 ng/mL for LC-MS/MS and 80 ng/mL for GC-MS), and ion suppression (for LC-ESI-MS/MS only) to allow the detection of benfluorex
metabolites 1-(m-trifluoromethylphenyl)-2-(2-hydroxyethyl)aminopropane (M1), 1-(m-trifluoromethylphenyl)-2-(2-carboxymethyl)aminopropane (M2), and 1-(m-trifluoromethylphenyl)-2-aminopropane (M3) as well as the glucuronic acid conjugate of M1. 相似文献
12.
Maxie Kohler Andreas Thomas Katja Walpurgis Wilhelm Schänzer Mario Thevis 《Analytical and bioanalytical chemistry》2010,398(3):1305-1312
Small interfering ribonucleic acid (siRNA) molecules can effect the expression of any gene by inducing the degradation of
mRNA. Therefore, these molecules can be of interest for illicit performance enhancement in sports by affecting different metabolic
pathways. An example of an efficient performance-enhancing gene knockdown is the myostatin gene that regulates muscle growth.
This study was carried out to provide a tool for the mass spectrometric detection of modified and unmodified siRNA from plasma
samples. The oligonucleotides are purified by centrifugal filtration and the use of an miRNA purification kit, followed by
flow-injection analysis using an Exactive mass spectrometer to yield the accurate masses of the sense and antisense strands.
Although chromatography and sensitive mass spectrometric analysis of oligonucleotides are still challenging, a method was
developed and validated that has adequate sensitivity (limit of detection 0.25–1 nmol mL−1) and performance (precision 11–21%, recovery 23–67%) for typical antisense oligonucleotides currently used in clinical studies. 相似文献
13.
Xylitol production by Debaryomyces hansenii NRRL Y-7426 was performed on synthetic medium varying the initial xylose concentration between 50 and 300 g/L. The experimental
results of these tests were used to investigate the effect of substrate level on xylose consumption by this yeast. Satisfactory
values of product yield on substrate (0.74–0.83 g/g) as well as volumetric productivity (0.481–0.694 g/L·h) were obtained
over a wide range of xylose levels (90–200 g/L), while a worsening of kinetic parameters took place at higher concentration,
likely due to a substrate inhibition phenomenon. The metabolic behavior of D. hansenii was studied, under these conditions, through a carbon material balance to estimate the fractions of xylose consumed by the
cell for different activities (xylitol production, biomass growth, and respiration) during the lag, exponential, and stationary
phases. 相似文献
14.
Various toxicological and metabolic interactions have been reported to exist between arsenic and selenium. In the present
study, synthetic seleno-arsenic compounds, potentially suitable for probing metabolic interactions between these two elements,
were prepared and tentatively characterized by using high-performance liquid chromatography (HPLC)–electrospray tandem mass
spectrometry and HPLC–inductively coupled plasma mass spectrometry. In analogy to the recently identified thio-arsenic species,
which can be prepared from their corresponding oxo-arsenic species via reaction with H2S, the seleno-arsenic compounds were also derived from oxo-arsenic compounds via reaction with H2Se.
Figure H2Se bubbled into solutions containing oxo‐arsenosugars converts them into their seleno‐arsenosugar analogues. 相似文献
15.
Nemutlu E Juranic N Zhang S Ward LE Dutta T Nair KS Terzic A Macura S Dzeja PP 《Analytical and bioanalytical chemistry》2012,403(3):697-706
A new method was here developed for the determination of 18O-labeling ratios in metabolic oligophosphates, such as ATP, at different phosphoryl moieties (α-, β-, and γ-ATP) using sensitive
and rapid electrospray ionization mass spectrometry (ESI-MS). The ESI-MS-based method for monitoring of 18O/16O exchange was validated with gas chromatography–mass spectrometry and 2D 31P NMR correlation spectroscopy, the current standard methods in labeling studies. Significant correlation was found between
isotopomer selective 2D 31P NMR spectroscopy and isotopomer less selective ESI-MS method. Results demonstrate that ESI-MS provides a robust analytical
platform for simultaneous determination of levels, 18O-labeling kinetics and turnover rates of α-, β-, and γ-phosphoryls in ATP molecule. Such method is advantageous for large
scale dynamic phosphometabolomic profiling of metabolic networks and acquiring information on the status of probed cellular
energetic system. 相似文献
16.
R. Schindler R. Vonach B. Lendl R. Kellner 《Fresenius' Journal of Analytical Chemistry》1998,362(1):130-136
A new process control methodology for the simultaneous determination of sugars, alcohols and organic acids in wine based
on multivariate evaluation of mid-IR transmission spectra of wine samples is presented. In addition to ethanol several lower
level wine components (glucose, fructose, glycerol, citric-, tartaric-, malic-, lactic- and acetic acid) were determined.
To establish a multivariate calibration model a set of 72 calibration solutions was prepared and measured, using a novel,
fully automated sequential injection (SI) system with Fourier transform infrared (FTIR) detection. The resulting spectra were
evaluated using a partial least square (PLS) model. The developed PLS model was then applied to the analysis of real wine
samples containing 79–91 g L–1 ethanol, 5.9–8.1 g L–1 glycerol, 0.4–6.9 g L–1 glucose, 1.5–7.5 g L–1 fructose, 0.3–1.6 g L–1 citric acid, 1.0–1.7 g L–1 tartaric acid, 0.02–3.2 g L–1 malic acid, 0.4–2.8 g L–1 lactic acid and 0.15–0.60 g L–1 acetic acid, yielding results which were in good agreement with those obtained by an external reference method (HPLC-IR).
The short analysis time (less than 3 min) together with high reproducibility makes the newly developed method applicable to
process control and screening purposes (average of the standard deviations calculated from four repetitive measurements of
six different real samples: ethanol: 0.55 g L–1, glycerol: 0.037 g L–1, glucose: 0.056 g L–1, fructose: 0.036 g L–1, citric acid: 0.020 g L–1, tartaric acid: 0.010 g L–1, malic acid: 0.052 g L–1, lactic acid: 0.012 g L–1 and acetic acid: 0.026 g L–1).
Received: 21 January 1998 / Revised: 5 March 1998 / Accepted: 6 March 1998 相似文献
17.
Summary The simultaneous quantitation of acids and sugars as their trimethyl silyl (TMS) derivatives has been extended in order to
identify and quantitate the simple acid and sugar constituents in the hydrolyzates of various immunostimulant, water-soluble
polysaccharides obtained from various Basidiomycetes, such as Armillariella mellea, Auricularia auricula-judae, Coriolus versicolor,
Flammulina velutipes, Fomes fomentarius, Ganoderma applanatum, Ganoderma lucidum, Pleurotus ostreatus, Schizophyllum commune,
Trametes hirsuta. Optimum hydrolysis conditions, performed with 2 M trifluoroacetic acid (TFAA) for five hrs, proved the presence
of several sugars and acids with maximum recovery. (i) the total sugar/sugar alcohol content of polysaccharides varied between
20- and 65% and consisted of arabitol (0.01–10.2%), arabinose (0.09–1.3%), ribose (0.2–1.8%), fucose (0.3–1.2%), mannitol
(0.01–5.3%), sorbitol (0.01–0.05%), galactiol (0.04%), fructose (0.08–0.8%), galactose (0.9–29%), glucose (10–53%), uronic
acids (0.14–3.7%), sucrose (0.03–2%), trehalose (0.2–1%), cellobiose (0.01–0.6%), maltose (0.2–1.9%), other disaccharides
(0.2–8%). (ii) The total of acids varied from 1.5 to 30% including o-phosphoric (1.3–19%), malic (0.08–4.7%), citric (0.08–4.7%),
isocitric; (3%) and C16−C18 fatty acids (1–6%). 相似文献
18.
Zou Hantao Yi Changhai Wang Luoxin Liu Hongtao Xu Weilin 《Journal of Thermal Analysis and Calorimetry》2009,97(3):929-935
Thermogravimetric (TG), differential thermal analysis (DTA) and thermal degradation kinetics, FTIR and X-ray diffraction (XRD)
analysis of synthesized glycine–montmorillonite (Gly–MMT) and montmorillonite bound dipeptide (Gly–Gly–MMT) along with pure
Na–MMT samples have been performed. TG analysis at the temperature range 25–250 °C showed a mass loss for pure Na–MMT, Gly–MMT
and Gly–Gly–MMT of about 8.0%, 4.0% and 2.0%, respectively. DTA curves show the endothermic reaction at 136, 211 and 678 °C
in pure Na–MMT whereas Gly–MMT shows the exothermic reaction at 322 and 404 °C and that of Gly–Gly–MMT at 371 °C. The activation
energies of the first order thermal degradation reaction were found to be 1.64 and 9.78 kJ mol−1 for Gly–MMT and Gly–Gly–MMT, respectively. FTIR analyses indicate that the intercalated compounds decomposed at the temperature
more than 250 °C in Gly–MMT and at 250 °C in Gly–Gly–MMT. 相似文献
19.
S. F. Malysheva N. K. Gusarova N. A. Belogorlova A. M. Nalibayeva S. V. Yasko N. A. Chernysheva S. I. Verkhoturova G. K. Bishimbayeva B. A. Trofimov 《Russian Journal of General Chemistry》2020,90(2):229-234
Bis(polyfluoroalkyl) chlorophosphites and polyfluoroalkyl dichlorophosphites react easily with secondary amines (from –40 to –22°C, 1–3 h, CH2Cl2) in the presence or absence of triethylamine to form the corresponding bis(polyfluoroalkyl) diorganylamidophosphites or bis(diorganylamido) polyfluoroalkyl phosphites in the yield of up to 74%. Bis(polyfluoroalkyl) diorganylamidophosphites were also synthesized from diorganylamidodichlorophosphites and polyfluoroalkanols (–25 to –22°C, 2 h, Et3N–CH2Cl2) with a yield of 56–60%. 相似文献
20.
Kinetics of biomethanation of solid tannery waste and the concept of interactive metabolic control 总被引:1,自引:0,他引:1
Anaerobic digestion of calf skin collagenous waste was optimized for a batch process based on accelerated maximal methane
yield per gram of input volatile solid. A kinetic analysis with respect to changes in the levels of volatile solid, collagen,
amino sugars, amino acids, hydroxyproline, ammonium ions, and volatile fatty acid were followed for a period of 80 d. Distinct
metabolic phases included an initial high rate collagenolysis for 4 d, with 50% degradation and was followed by an acidogenic
phase between 4–12 d with voltatile fatty acids levels increasing to 215 mmol/L. Subsequently methanogenesis ensued and was
maximal between 12–24 d when volatile fatty acids attained steady state levels. During the period of 80 d, the overall decrease
in volatile solid level was 65%, whereas the collagen level declined by 85% with 0.45 L of methane yield/g of volatile solid
degraded. Based on the levels of various metabolites detected, the concept of interactive metabolic control earlier proposed
has been validated. 相似文献