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1.
Bioconversion of possible T-2 toxin precursors by a mutant strain of Fusarium sporotrichioides NRRL 3299. 总被引:5,自引:3,他引:2
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Liquid cultures of a mutant strain of Fusarium sporotrichioides NRRL 3299 that accumulates trichodiene rather than T-2 toxin converted tricho-9-ene-2 alpha,3 alpha,11 alpha-triol, trichotriol (tricho-10-ene-2 alpha,3 alpha,9 alpha-triol), tricho-10-ene-2 alpha,3 alpha,9 beta-triol, 3 alpha-hydroxytrichothecene, and 3 alpha-acetoxytrichothecene to T-2 toxin. Other possible oxygenated precursors of T-2 toxin, including trichodiol (tricho-10-ene-2 alpha,9 alpha-diol), trichothecene, 4 alpha-hydroxytrichothecene, and 15-hydroxytrichothecene, were not metabolized. The results indicate that in the biosynthesis of T-2 toxin by F. sporotrichioides, (i) oxygenation at C-3 occurs prior to the second cyclization, (ii) this second cyclization involves two steps that may be nonenzymatic, and (iii) oxidation at C-3 precedes that at C-4 or C-15. 相似文献
2.
S P McCormick S L Taylor R D Plattner M N Beremand 《Applied and environmental microbiology》1990,56(3):702-706
Liquid cultures of a mutant strain of Fusarium sporotrichioides NRRL 3299 that accumulates trichodiene rather than T-2 toxin converted tricho-9-ene-2 alpha,3 alpha,11 alpha-triol, trichotriol (tricho-10-ene-2 alpha,3 alpha,9 alpha-triol), tricho-10-ene-2 alpha,3 alpha,9 beta-triol, 3 alpha-hydroxytrichothecene, and 3 alpha-acetoxytrichothecene to T-2 toxin. Other possible oxygenated precursors of T-2 toxin, including trichodiol (tricho-10-ene-2 alpha,9 alpha-diol), trichothecene, 4 alpha-hydroxytrichothecene, and 15-hydroxytrichothecene, were not metabolized. The results indicate that in the biosynthesis of T-2 toxin by F. sporotrichioides, (i) oxygenation at C-3 occurs prior to the second cyclization, (ii) this second cyclization involves two steps that may be nonenzymatic, and (iii) oxidation at C-3 precedes that at C-4 or C-15. 相似文献
3.
J L Ram S Patel 《Comparative biochemistry and physiology. A, Comparative physiology》1989,93(4):745-749
1. Aplysia buccal muscle E1 can be skinned with saponin in a low ionic strength medium. Pulses of calcium, which were ineffective at causing contraction in intact fibers, elicited contraction in skinned fibers. 2. Tension in skinned fibers increased at [Ca2+] greater than 10(-7) M and was maximal at 6 x 10(-7) M. 10(-5) M [Ca2+] caused irreversible damage to the fibers. 3. Fibers did not exhibit "catch", i.e. they relaxed quickly upon removal of calcium. 4. Optimal pH for tension was 7.0. 5. Contractile responses to calcium pulses were increased by raising "background" [Ca2+] to 10(-7) M. 6. Cyclic AMP (10(-4) and 10(-3) M) had no effect on tension. 相似文献
4.
The duckweed Lemna minor L. clone St was used to investigate the effect of 10 heavy metals under the standardised test conditions of the ISO protocol 20079. By using growth rates derived from frond number (FN), fresh weight (FW), dry weight (DW), chlorophyll and carotenoid (Car) contents, concentration–response curves for all heavy metals and all growth parameters were classified. In addition, all data were fitted to obtain the inhibitions of growth rates (ErCx) at the level of 10%, 20% and 50% (ErC10, ErC20 and ErC50, respectively) then used to evaluate the phytotoxicity of the different heavy metals. On the basis of the ErC50 values (average ranking of all five growth parameters), the following series of phytotoxicity was detected by using molar concentrations: Ag+>Cd2+>Hg2+>Tl+>Cu2+>Ni2+>Zn2+>Co2+>Cr(VI)>As(III)>As(V). 相似文献
5.
Stimulation of inositol trisphosphate formation in hepatocytes by vasopressin, adrenaline and angiotensin II and its relationship to changes in cytosolic free Ca2+. 总被引:33,自引:28,他引:5
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At maximally effective concentrations, vasopressin (10(-7) M) increased myo-inositol trisphosphate (IP3) in isolated rat hepatocytes by 100% at 3 s and 150% at 6 s, while adrenaline (epinephrine) (10(-5) M) produced a 17% increase at 3 s and a 30% increase at 6 s. These increases were maintained for at least 10 min. Both agents increased cytosolic free Ca2+ [( Ca2+]i) maximally by 5 s. Increases in IP3 were also observed with angiotensin II and ATP, but not with glucagon or platelet-activating factor. The dose-responses of vasopressin and adrenaline on phosphorylase and [Ca2+]i showed a close correspondence, whereas IP3 accumulation was 20-30-fold less sensitive. However, significant (20%) increases in IP3 could be observed with 10(-9) M-vasopressin and 10(-7) M-adrenaline, which induce near-maximal phosphorylase activation. Vasopressin-induced accumulation of IP3 was potentiated by 10mM-Li+, after a lag of approx. 1 min. However the rise in [Ca2+]i and phosphorylase activation were not potentiated at any time examined. Similar data were obtained with adrenaline as agonist. Lowering the extracellular Ca2+ to 30 microM or 250 microM did not affect the initial rise in [Ca2+]i with vasopressin but resulted in a rapid decline in [Ca2+]i. Brief chelation of extracellular Ca2+ for times up to 4 min also did not impair the rate or magnitude of the increase in [Ca2+]i or phosphorylase a induced by vasopressin. The following conclusions are drawn from these studies. IP3 is increased in rat hepatocytes by vasopressin, adrenaline, angiotensin II and ATP. The temporal relationships of its accumulation to the increases in [Ca2+]i and phosphorylase a are consistent with it playing a second message role. Influx of extracellular Ca2+ is not required for the initial rise in [Ca2+]i induced by these agonists, but is required for the maintenance of the elevated [Ca2+]i. 相似文献
6.
Ruhwald M Petersen J Kofoed K Nakaoka H Cuevas LE Lawson L Squire SB Eugen-Olsen J Ravn P 《PloS one》2008,3(8):e2858
Background
There is a need for simple tools such as the M.tuberculosis specific IFN-γ release assays (IGRA) to improve diagnosis of M.tuberculosis-infection in children. The aim of the study was to evaluate the performance of an IP-10 and IL-2 based tests for the diagnosis of M.tuberculosis-infection in recently exposed children from Nigeria.Methodology and Principal Findings
Samples were obtained from 59 children at high risk of infection with M.tuberculosis (contacts of adults with smear and culture-positive tuberculosis) and 61 at low risk (contacts of smear-negative/culture-positive tuberculosis or community controls). IP-10 and IL-2 was measured in plasma after stimulation of whole-blood with M.tuberculosis specific antigens and mitogen. Previously developed criteria for positive IP-10 and IL-2 tests were used and the diagnostic performances of the IP-10 and IL-2 tests were compared with the Quantiferon In-Tube (QFT-IT) and the Tuberculin Skin Tests (TST). In response to M.tuberculosis specific antigens, the high-risk children expressed significantly higher levels of IP-10 (1358 pg/ml[IQR 278–2535 pg/ml]) and IL-2 (164 pg/ml[11–590 pg/ml]) than low risk groups 149 pg/ml(25–497 pg/ml), and 0 pg/ml(0–3 pg/ml), respectively. There was excellent agreement (>89%,k>0.80) between IP-10, IL-2 tests and QFT-IT, better than with TST (>74%,k>0.49). The IP-10 and IL-2 responses were strongly associated with M.tuberculosis exposure and with grade of infectiousness of the index cases (p<0.0001). IP-10, IL-2, and TST but not QFT-IT was associated with age of the child in the low risk groups (p<0.02).Conclusions/Significance
IP-10 is expressed in high levels and results of the IP-10 test were comparable to the QFT-IT. IL-2 was released in low amounts in response to the antigens and not in response to the mitogen therefore IL-2 seems a less useful marker. We have demonstrated that IP-10 and possibly IL-2 could be alternative or adjunct markers to IFN-γ in the diagnosis infection with M.tuberculosis. 相似文献7.
Air-dried cells of Hansenula nonfermentans AKU 4332 catalyzed the production of (S)-3-pentyn-2-ol from (RS)-3- pentyn-2-ol acetate ester at 10% (v/v). The product was formed at 96.6% e.e. with a molar yield of 45% in 24 h. © Rapid Science Ltd. 1998 相似文献
8.
The 19-methyl analogues of androstenedione and its aromatization intermediates (19-hydroxyandrostenedione and 19-oxoandrostenedione) were evaluated as substrates of microsomal aromatase in order to determine the effect of a 19-alkyl substituent on the enzyme's regiospecificity. Neither the androstenedione analogue [10-ethylestr-4-ene-3,17-dione (1c)] nor the 19-oxoandrostenedione analogue [10-acetylestr-4-ene-3,17-dione (3c)] was converted to estrogens or oxygenated metabolites by placental microsomes. In contrast, both analogues of 19-hydroxyandrostenedione [10-[(1S)-1-hydroxyethyl]estr-4-ene-3,17-dione (2c) and 10-[(1R)-1-hydroxyethyl]estr-4-ene-3,17-dione (2e)] were converted to the intermediate analogue 3c in a process requiring O2 and either NADH or NADPH. No change in enzyme regiospecificity was detected. The absolute configuration of 2e was determined by X-ray crystallography. Experiments with 18O2 established that 3c generated from 2c retained little 18O (less than 3%), while 3c arising from 2e retained a significant amount of 18O (approximately equal to 70%). All four 19-methyl steroids elicited type I difference spectra from placental microsomes in addition to acting as competitive inhibitors of aromatase (KI = 81 nM, 11 microM, 9.9 microM, and 150 nM for 1c, 2c, 2e, and 3c, respectively). Pretreatment of microsomes with 4-hydroxyandrostenedione (a suicide inactivator of aromatase) abolished the metabolism of 2c and 2e to 3c, as well as the type I difference spectrum elicited by 2c and 2e.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Preliminary crystallographic study of the phenylalanyl-tRNA synthetase from Thermus thermophilus HB8
M M Chernaya S V Korolev L S Reshetnikova M G Safro 《Journal of molecular biology》1987,198(3):555-556
Phenylalanyl-tRNA synthetase (EC 6.1.1.20) from the extreme thermophile Thermus thermophilus HB8 has been isolated and crystallized. The enzyme was found to consist of two types of subunits with molecular masses 38 X 10(3) (alpha) and 94 X 10(3) (beta) and is likely to be a tetrameric protein with a molecular mass of about 260 X 10(3) (alpha 2 beta 2). Crystals of phenylalanyl-tRNA synthetase were grown by the hanging-drop technique at 4 degrees C in the presence of ammonium sulfate. Trigonal crystals, space group P3(1)21, with cell dimensions a = b = 176 A and c = 142 A (1 A = 0.1 nm), are suitable for medium-resolution X-ray analysis. 相似文献
10.
Dynamics of microbial communities on marine snow aggregates: colonization,growth, detachment,and grazing mortality of attached bacteria 总被引:2,自引:0,他引:2
We studied the dynamics of microbial communities attached to model aggregates (4-mm-diameter agar spheres) and the component processes of colonization, detachment, growth, and grazing mortality. Agar spheres incubated in raw seawater were rapidly colonized by bacteria, followed by flagellates and ciliates. Colonization can be described as a diffusion process, and encounter volume rates were estimated at about 0.01 and 0.1 cm(3) h(-1) for bacteria and flagellates, respectively. After initial colonization, the abundances of flagellates and ciliates remained approximately constant at 10(3) to 10(4) and approximately 10(2) cells sphere(-1), respectively, whereas bacterial populations increased at a declining rate to >10(7) cells sphere(-1). Attached microorganisms initially detached at high specific rates of approximately 10(-2) min(-1), but the bacteria gradually became irreversibly attached to the spheres. Bacterial growth (0 to 2 day(-1)) was density dependent and declined hyperbolically when cell density exceeded a threshold. Bacterivorous flagellates grazed on the sphere surface at an average saturated rate of 15 bacteria flagellate(-1) h(-1). At low bacterial densities, the flagellate surface clearance rate was approximately 5 x 10(-7) cm(2) min(-1), but it declined hyperbolically with increasing bacterial density. Using the experimentally estimated process rates and integrating the component processes in a simple model reproduces the main features of the observed microbial population dynamics. Differences between observed and predicted population dynamics suggest, however, that other factors, e.g., antagonistic interactions between bacteria, are of importance in shaping marine snow microbial communities. 相似文献
11.
Tow types of dose-rate effect that alter the survival response of haploid yeast cells to 8-methoxypsoralen (8-MOP) plus treatment with irradiation at 365 nm were studied. (1) When the concentration of 8-MOP was varied between 9.2 X 10(-5) and 2.3 X 10(-8) M and the dose rate of 365-nm irradiation kept constant, the efficiency of the irradiation for killing increased relatively to that of 8-MOP whe the concentration of 8-MOP decreased. This indicated that there was no strict reciprocity between radiation dose and concentration of drug. (2) When the dose rate of radiation was varied between 0.66 X 10(3) and 108 X 10(3) J m-2 h-1 and the concentration of 8-MOP was kept constant, the survival of wild-type cells increased strikingly at low dose rates of radiation as compared with high dose rates. Cells responded more to changes at low dose rates than to equal changes a high dose rates. The high resistance of wild-type cells to 8-MOP plus radiation delivered at low dose rates absent from rad 1-3 cells defective in excision-repair. This suggests that the dose-rate effect seen in wild-type cells depended at least in part on an active excision-repair function. At low dose rates of radiation, the shoulder of the survival curve for rad1-3 cells, i.e. the ability to accumulate sub-lethal damage, was increased by a factor of about 2 when compared with that seen at a high dose rate. Thus it is likely that at low dose rates a repair function other than excision-resynthesis may operate in rad1-3 cells. 相似文献
12.
The four possible isomers of 3-benzyloxy-16-hydroxymethylestra-1,3,5(10)-trien-17-ol (1a-4a) with proven configurations were converted into the corresponding 3-benzyloxy-16-bromomethylestra-1,3,5(10)-triene-3,17-diols (5e-8e). Depending on the reaction conditions the cis isomers of 3-benzyloxy-16-hydroxymethylestra-1,3,5(10)-trien-17-ol (1a and 2a) were transformed into 3-benzyloxy-16-bromomethylestra-1,3,5(10)-trien-17-yl acetate (5b and 6b) or 16-bromomethyl-3-hydroxyestra-1,3,5(10)-trien-17-yl acetate (5c and 6c) on treatment with HBr and acetic acid. The mechanism of the process can be interpreted as involving front-side neighboring group participation. Under similar experimental conditions, the trans isomers (3a and 4a) yielded only 3-benzyloxy-16-acetoxymethylestra-1,3,5(10)-trien-17-yl acetates (3b and 4b) or 16-acetoxymethylestra-1,3,5(10)-triene-3,17-diyl diacetates (3d and 4d). Both the cis (1a and 2a) and the trans (3a, and 4a) isomers were transformed into 16-bromomethylestra-1,3,5(10)-trien-17-ol (5a-8a) by the Appel reaction on treatment with CBr4/Ph3P. Debenzylation of 5a-8a was carried out with HBr and acetic acid to yield 5e-8e. The debenzylation process in the presence of acetic anhydride produces the diacetates 5d-8d. The structures of the compounds were determined by means of MS, 1H NMR and 13C NMR spectroscopic methods. Compounds 5c-8c and 5e-8e were tested in a radioligand-binding assay. Except for the affinity of 7e for the estrogen receptor (Ki=2.55 nM), the affinities of the eight compounds (5c-8c and 5e-8e) for the estrogen, androgen and progesterone receptors are low (Ki > 0.55, 0.52 and 0.21 microM, respectively). 相似文献
13.
1. Homogenates of tissues from females of the nematode Heterodera glycines were clarified by centrifugation and used to initiate characterization of soluble esterases using p-nitrophenyl acetate as the substrate. 2. Optimum temperature and pH were 40 degrees C and 7.2 respectively. 3. Acetazolamide (a carbonic anhydrase inhibitor) at 10(-3) M did not inhibit enzyme activity, indicating that carbonic anhydrase was not present. 4. Phenamiphos (an organophosphate) at 10(-6) M reduced activity by 38%, whereas eserine hemisulfate (a cholinesterase inhibitor) and aldicarb (a carbamate) were not inhibitory at that concentration, indicating that there was no cholinesterase activity. 5. Eserine hemisulfate, aldicarb, and phenamiphos inhibited enzyme activity by 50% (I50) at 5 x 10(-3) M, 7.5 x 10(-4) M, and 6 x 10(-6) M, respectively. 6. Approximately 25% of the activity detected appeared due to A- and/or C-esterases. 7. The data demonstrated that aldicarb and phenamiphos were active against esterases other than acetylcholinesterase. 相似文献
14.
Protection of Chinese hamster ovary cells from hyperthermic killing by cycloheximide or puromycin 总被引:2,自引:0,他引:2
Cycloheximide (CHM) and puromycin (PUR) were used at various concentrations up to maxima of 10 micrograms/ml and 100 micrograms/ml, respectively, which inhibited protein synthesis by 95% without any cytotoxicity. The drugs were added to the cells for a maximum period of 7 h, with various combinations for treatment before, during, and after heating. Maximum protection, i.e., a 10,000-fold increase in survival from 5 X 10(-6) to 5 X 10(-2) after 4 h at 43 degrees C, required both 1-2 h of treatment before heating and 1-2 h of treatment during heating. For treatments at 45.5 degrees C, the protection was less, i.e., a 100-fold increase in survival from 10(-5) to 10(-3). Little or no protection was observed if after treatment, the drug was removed before heating, or if the drug was added at the start of heating and left on for 5 min to 3 h after heating. For both drugs, the amount of protection increased as inhibition of protein synthesis increased. However, the amount of protection from the drugs was the same only at about 95% inhibition; at 60-85% inhibition, CHM afforded more protection than PUR. Therefore, the modes of action of the drugs might be common at high drug concentrations, but different when intermediate concentrations are used. 相似文献
15.
S J Prestrelski D M Byler M P Thompson 《International journal of peptide and protein research》1991,37(6):508-512
We have undertaken a new and more detailed Fourier-transform infrared (FTIR) spectroscopic study of alpha-lactalbumin (in D2O solution) aimed at correlating its secondary structures to observed Amide I' infrared bands. The spectra reported here were interpreted in light of the recently determined crystal structure of alpha-lactalbumin and by comparison with the spectra and structure of the homologous protein lysozyme. Of particular importance is the new evidence supporting the assignment of the band at 1639 cm-1 to 3(10)-helices. This assignment is in excellent agreement with one based on theoretical and experimental studies of 3(10)-helical polypeptides. The frequency observed for 3(10)-helices is distinctly different from that at which alpha-helices are typically found (viz., around 1655 cm-1). In the present study, two bands are clearly resolved in the latter region at 1651 and 1659 cm-1. Both are apparently associated with alpha-helices. These results suggest that for D2O solutions of globular proteins. FTIR spectroscopy can be a facile method for detecting the presence of these two different types of helical conformation and distinguishing between them. This provides a distinct advantage over ultraviolet circular dichroism spectroscopy (UV-CD). This work also provides a basis for future studies of alpha-lactalbumin which examine the effects of environment (e.g., pH, temperature) and ligands (e.g., Ca2+, Mn2+) on its conformation. 相似文献
16.
(1) Cyanamide (N identical to C-NH2) has been shown to be a substrate for purified Mo-nitrogenases of Klebsiella pneumoniae and Azotobacter chroococcum, with apparent Km values near 0.8 mM. (2) Reduction products were CH4, CH3NH2 and NH3 formed by pathways requiring 6 or 8 electrons: N identical to CNH2 + 6e + 6H+----CH3NH2 + NH3; N identical to CNH2 + 8e + 8H+----CH4 + 2NH3 (3) Acetylene reduction and hydrogen evolution were inhibited more than 75% by cyanamide (10 mM). Cyanamide also inhibited total electron flux at nitrogenase protein component ratios (Fe/MoFe) near 10. (4) Cyanamide was also a substrate for the recently isolated Va-nitrogenase of A. chroococcum, but with an apparent Km of 2.6 mM showed weaker binding and an 8-fold lower Vmax than did either Mo-nitrogenase. (5) The component ratios of nitrogenase proteins favouring CH4 formation was 3.5 Fe/MoFe protein and 1 Fe/VaFe protein. 相似文献
17.
Shi WQ Fu HY Bounds PL Muroya Y Lin MZ Katsumura Y Zhao YL Chai ZF 《Radiation research》2011,176(1):128-133
3-Nitrotyrosine has been reported as an important biomarker of oxidative stress that may play a role in a variety of diseases. In this work, transient UV-visible absorption spectra and kinetics observed during the reaction of the hydrated electron, e(aq)(-), with 3-nitrotyrosine and derivatives thereof were investigated. The absorption spectra show characteristics of aromatic nitro anion radicals. The absorptivity of radical anion product at 300 nm is estimated to be (1.0 ± 0.2) × 10(4) M(-1) cm(-1) at pH 7.3. The rate constants determined for the reaction of e(aq)(-) with 3-nitrotyrosine, N-acetyl-3-nitrotyrosine ethyl ester and glycylnitrotyrosylglycine at neutral pH (3.0 ± 0.3) × 10(10) M(-1) s(-1), (2.9 ± 0.2) × 10(10) M(-1) s(-1) and (1.9 ± 0.2) × 10(10) M(-1) s(-1), respectively, approach the diffusion-control limit and are almost two orders of magnitude higher than those for the reactions with tyrosine and tyrosine-containing peptides. The magnitude of the rate constants supports reaction of e(aq)(-) at the nitro group, and the product absorbance at 300 nm is consistent with formation of the nitro anion radical. The pH dependence of the second-order rate constant for e(aq)(-) decay (720 nm) in the presence of 3-nitrotyrosine shows a decrease with increasing pH, consistent with unfavorable electrostatic interactions. The pH dependence of the second-order rate constant for formation of radical anion (300 nm) product suggests that deprotonation of the amino group slows the rate, which indicates that deamination to form the 1-carboxy-2-(4-hydroxy-3-nitrophenyl)ethyl radical occurs. We conclude that the presence of the nitro group activates tyrosine and derivatives toward reaction with e(aq)(-) and can affect the redox chemistry of biomolecules exposed to oxidative stress. 相似文献
18.
The clastogenic potential of the intercalating compound ellipticine, an antitumor alkaloid, has been demonstrated in mammalian cells. To characterize the mechanism of action of this drug over the cell cycle, human lymphocyte cultures from 2 healthy donors were treated with 3 micrograms/ml ellipticine in 30-min pulses during different phases of the cell cycle and analyzed for chromosomal aberrations and sister-chromatid exchanges. The G2 phase was most sensitive in terms of induction of aberrations, followed by S and G1. Chromatid-type aberrations were the most common type of chromosomal damage. Induction of SCEs was significantly high only after treatment at G1, when the frequencies of SCEs doubled. The post-treatment effect of lymphocytes with inhibitors of DNA repair, 10(-3) M caffeine and 5 x 10(-6) M 1-beta-D-arabinofuranosylcytosine, was also tested by adding 3 micrograms/ml ellipticine at G2 in 30-min pulses and immediately followed by caffeine and/or ara-C during the last 3 h before harvesting. Three experiments performed on blood from 3 donors showed a moderate potentiation effect on the frequency of chromatid-type aberrations (about 2-3 times) by both inhibitors. Likewise, a 3-fold increase was observed in the frequencies of chromosomal aberrations when caffeine and ara-C were combined. The present data demonstrate that posttreatment with caffeine and ara-C at G2 can modify the response of human lymphocytes treated with ellipticine by increasing the clastogenic action of this compound or by changing the cell-cycle progression. 相似文献
19.
Effects of static magnetic fields on diffusion in solutions 总被引:2,自引:0,他引:2
Static magnetic fields affect the diffusion of biological particles in solutions through the Lorentz force and Maxwell stress. These effects were analyzed theoretically to estimate the threshold field strength for these effects. Our results show that the Lorentz force suppresses the diffusion of charged particles such as Na+, K+, Ca2+, Cl-, and plasma proteins. However, the threshold is so high, i.e., more than 10(4) T, that the Lorentz force does not affect the ion diffusion at typical field strengths (a few Tesla at most). Since the threshold of gradient fields for producing a change in ion diffusion through the Maxwell stress is more than 10(5) T2/m for paramagnetic molecules (FeCl3, O2) and plasma proteins, their diffusion would be unaffected by typical gradient fields (100 T2/m at most) and even by high gradient fields (less than 10(5) T2/m) used in magnetic separation techniques. In contrast, movement of deoxygenated erythrocytes and FeCl3 colloids (more than 10(3) molecules) is influenced by the usual gradient fields due to a volume effect. 相似文献
20.
A Balagopal L Gama V Franco JN Russell J Quinn Y Higgins LM Smeaton JE Clements DL Thomas A Gupta;for the NWCS ACTG study team 《PloS one》2012,7(8):e41258