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At least 775 records · Page 43Linked to original sources
PubMed1993

Multielectrode spiral cuff for ordered and reversed activation of nerve fibres.

In this paper we present the modelling, design, and experimental testing of a nerve cuff multielectrode system for selective activation of fibres in superficial peripheral nerve trunk regions which is capable of activating fibres in physiological order. The multielectrode system consists of 45 platinum electrodes embedded within a self-curling spiral silicone sheet organized in fifteen longitudinal groups consisting of three electrodes spaced equidistally around the circumference of the cuff. Electrodes in the centre band acted as stimulating cathodes while the two electrodes of the same group in the two outer bands were connected together and corresponded to the position of a particular cathode, serving as anodes to block the nascent action potentials by membrane hyperpolarization. The interpolar distance was 6 mm on both sides, resulting in a total cuff length of about 20 mm. The cuff was constructed with a diameter to fit the size of the dog sciatic nerve. Preliminary animal testing of the nerve cuff was performed on the sciatic nerve of a Bigley female dog. In the 45-electrode stimulation system, biphasic cathodic first pulses with quasitrapezoidal-shaped cathodic and square anodic parts were delivered through the particular group of tripolar electrodes to effect both selective stimulation of motor axons within the gastrocnemius muscle fascicle, and differential block by membrane hyperpolarization. The test was repeated using rectangular cathodic first biphasic current pulses delivered monopolarly on the central electrode of the same group while connected anodes were replaced by a common anode situated elsewhere in the surrounding tissue. In both experiments an isometric torque in the ankle joint elicited by the gastrocnemius muscle was measured and compared.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

New polyacrylamide matrices for drift-free isoelectric focusing.

The major cause for pH gradient decay and cathodic drift during isoelectric focusing in polyacrylamide gels has been found to be electroendo-osmotic flow generated by fixed charges in the gel matrix. These changes have the following causes: (a) trace impurities of acrylic acid in the co-monomers; (b) covalent incorporation of catalysts (persulphate and riboflavin 5'-phosphate) as terminal groups in polyacrylamide chains; (c) hydrolysis of amide groups to acrylic acid in the gel layer underneath the cathodic filter paper strip. The result of these fixed negative charges in the matrix is a movement of counter-ions with hydration water towards the cathode (i.e. electroendo-osmosis) with concomitant drift of pH gradient and focused protein zones in the same direction. It is impossible to cure the cathodic drift by increasing the pH of the anolyte, or decreasing the pH of the catholyte, or both, as previously suggested. One way to reduce the cathodic drift efficiently is to incorporate covalently in the matrix tertiary or quaternary groups (3-dimethylaminopropylmethacrylamide) in stoichiometric amounts as compared with the negative charges. This 'balanced' polyacrylamide displays zero drift for at least 5000 V.h, which is considered to be an ample time for equilibrium separation of protein species in isoelectric focusing.

Chemical Phenomena↗
PubMed1986

Structural and functional studies of the king salmon, Oncorhynchus tshawytscha, hemoglobins.

Vertical starch-gel electrophoresis at pH 8.6 revealed extensive hemoglobin multiplicity with several distinct cathodal and anodal hemoglobin components. Anodal hemoglobin components are present throughout the life cycle of the king salmon. Additional cathodal components are found in the adult fish. Cathodal hemoglobin components exhibited a higher oxygen affinity (P50 = 10.2 mm at 13 degrees C, pH 7.3) than the anodal hemoglobin components (P50 = 21.8 mmHg at 13 degrees C). Oxygen binding of the anodal hemoglobins are sensitive to pH, temperature, organic phosphates (ATP and GTP), as well as, ionic strength; binding of oxygen to the cathodal hemoglobins is independent of pH and not affected by organic phosphates. Anodal hemoglobin components are less resistant to thermal denaturation over the pH 6.0 to 8.0 range. Isothermal urea denaturation of separated anodal and cathodal hemoglobin fractions of the king salmon indicate inherent differences in the stabilization energies of these hemoglobins. Autoxidation of these hemoglobins occurs around pH 7.0 and below, as well as, in the presence of increasing Cl- concentrations.

Animals↗
PubMed2005

Changes of the solution pH due to exposure by high-voltage electric pulses.

The change of the pH of a NaCl solution (139-149 mM NaCl) buffered with 5-15 mM sodium phosphates (pH 7.4) during electromanipulation was studied. It has been determined that an increase in the pH value of electroporation solution of a whole chamber volume, caused by the application of electric field pulses, commonly used in cell electromanipulation procedures, can exceed 1-2 pH units. Several materials for the cathode were tested. In all cases a stainless steel anode was utilized. The aluminum cathode gave a two-fold greater DeltapH in comparison with platinum, copper or stainless steel cathodes. In addition, a substantial release of aluminum (up to 1 mg/l) from the cathode was observed. It has also been found that the shift in pH depended on the medium conductivity: DeltapH of the solution, in which sucrose was substituted for NaCl, was about 5 times less. On the basis of the results obtained here, to avoid the plausible undesirable consequences of the cathodic electrolysis processes, in particular under the conditions of strong electric treatment, it could be recommended that chambers with aluminum electrodes not be utilized and one should use strongly buffered solutions of low conductivity and alternating current (sine or square wave) bipolar electric pulses.

Electricity↗
PubMed2006

Thresholds for activation of rabbit retinal ganglion cells with a subretinal electrode.

The ultimate success of a retinal prosthesis to create vision will likely depend upon developing a base of knowledge of how best to electrically stimulate the retina. Previously, we studied the responses of rabbit retinal ganglion cells (RGCs) to current pulses applied with an electrode placed on the epiretinal surface. In the present study, we examined the responses of rabbit RGCs to current pulses applied with a subretinal electrode. Single-unit extracellular recordings were made from OFF RGCs and ON RGCs in isolated retinas, which were stimulated with monophasic current pulses (0.1-50ms in duration), delivered through a 500-mum diameter electrode. All RGCs elicited one or more bursts of action potentials upon electrical stimulation of the retina. The timing of the bursts depended upon both the polarity of the electrical stimulus and the RGC type. With near-threshold current pulses, the response latencies of OFF RGCs to anodal stimulation were comparable to those of ON RGCs to cathodal stimulation, whereas the response latencies of OFF RGCs to cathodal stimulation were comparable to those of ON RGCs to anodal stimulation. Threshold currents for activation of RGCs decreased with increased pulse duration. For OFF RGCs, threshold currents for cathodal current pulses were, on average, 2-7.5 times higher (depending upon pulse duration) than the threshold currents for anodal current pulses. For ON RGCs, threshold currents for cathodal and anodal current pulses were, on average, nearly identical for all pulse durations and were equivalent to threshold currents of OFF RGCs to anodal stimulation. With respect to a subretinal prosthesis, our findings suggest the possibility that cathodal current pulses may bias activation of ON RGCs in blind patients.

Action Potentials↗
PubMed2004

Bench- and field-scale evaluation of chromium and cadmium extraction by electrokinetics.

The results of bench-scale laboratory tests and in situ, pilot-scale demonstration of electrokinetic extraction of chromium and cadmium from contaminated soil are presented. The laboratory tests were conducted using 10 cm long samples under current density of 5A/m(2) for 1200 h. Tests were conducted with and without citric acid amendment at the cathode. The results showed that citric acid improved extraction, especially in the sections near the cathode. However, processing was not enough to result in complete cleanup. The field demo was conducted at the Naval Air Weapon Station (NAWS), Point Mugu, California. Three cathodes were centered between six anodes. The anode-cathode spacing was 4.45 m (15 ft). Constant voltage of 60 V ( approximately 13 V/m) was applied for 20 days and then was reduced to 45 V (10 V/m) for 6 months. Citric acid was used to maintain the cathode pH at 4. After 6 months of treatment, 78% of the soil volume has been cleared of chromium or treated to below natural background levels. The results also indicated that 70% of the soil between the electrodes had been cleared of cadmium contamination. A comparison between the bench-scale and field demo showed that the field process was more effective than the lab tests. This indicated that small sample size will induce a negative effect on the efficiency of the process due to an increased impact of the boundaries on the overall process.

Cadmium↗
PubMed2006

Perception of the vertical in patients with right hemispheric lesion: effect of galvanic vestibular stimulation.

Patients with right-brain injury present, more frequently in the acute phase, with a deviation of the subjective vertical (SV) contralateral to the lesion. The aim of this study was to investigate the influence of galvanic vestibular stimulation (GVS) on this disorder. Twelve patients presenting with a right hemispheric lesion, seven with neglect (N+) and five without (N-) were compared to eight control subjects. They had to orient vertically a luminous rod in darkness, in three galvanic stimulation (1.5 mA) conditions: cathode left, cathode right and no stimulation (baseline). Without stimulation, the patients' SV, and especially that of N+, showed an anticlockwise deviation. In comparison with baseline values, GVS induced a deviation toward the side opposite to the cathode in the three groups. In the patients, the deviation was of larger amplitude and appeared greater for left than for right cathodic stimulation. In conclusion, we showed an influence of vestibular stimulation on the SV of right brain-injured patients, especially when spatial neglect was present. As left cathodic stimulation can reduce the SV deviation associated with spatial neglect, such a tool could be introduced in rehabilitation.

Adult↗
PubMed2001

Design parameters for an electrochemical cell with porous electrode to treat metal-ion solution.

An electrochemical reactor was designed and operated to treat the solution containing copper ions. Design parameters for the electrochemical reactor using the porous cathode and RuO2/IrO2/Ti anode were investigated. The porous cathode was prepared by the electroless nickel deposition on polyurethane. The apparent current, the gap between cathode and anode, and hydraulic retention time (HRT) were selected as design parameters. The copper removal rate increased with an increase in apparent current. It was not affected by the gap between the cathode and the anode. A reduction in hydraulic retention time stimulated the mass transfer toward the electrode and increased the cathodic current efficiency. Dimensional analysis was conducted to obtain the design equation for scale-up of the electrochemical reactor. The dependence of Sh on Re, Sc, and characteristic lengths, DC/A/L and DW/C/L, was described in the form of a power series. The coefficients were obtained from experimental data.

Cations↗
PubMed1998

Transdermal iontophoresis: modulation of electroosmosis by polypeptide.

The objective of this research was to further evaluate the relative importance of electrorepulsion and electroosmosis to the mechanism of enhanced transport across the skin during iontophoresis. Specifically, the impact of iontophoresing into the skin positively and negatively charged polypeptides (poly-L-lysines and poly-L-glutamic acids, respectively) on the membrane's permselectivity and hence on the quantity and direction of electroosmotic flow, was examined. Experiments were performed in vitro at pH 7.4 using conventional methodology; electroosmosis during the iontophoresis of the polypeptides into and across the skin was tracked in the usual way via the movement of the polar, uncharged, non-metabolizable marker, D-mannitol. Electrotransport of the cationic polypeptides attenuated electroosmotic flow in the normal anode-to-cathode direction; the degree of inhibition was correlated both with the initial concentration of poly-L-lysine in the anodal chamber and with the molecular weight of the polypeptide employed (from 1 to 25 kilodaltons). Iontophoresis of the anionic poly-L-glutamic acids from the cathode provoked a slight increase in electroosmotic flow in the 'reverse' direction (i.e. from the receptor phase beneath the skin towards the cathode chamber located on the epidermal side of the membrane); this effect, however, was much less dramatic than that produced in the opposite sense by the cationic polypeptides. The results suggest that driving large positively-charged polypeptide molecules into the skin leads to neutralization of the membrane's negativity, a subsequent loss of permselectivity and a concomitant attenuation of electroosmosis in the conventional anode-to-cathode direction. Presumably, the relatively poor iontophoretic permeability of these species (which becomes more and more evident with increasing molecular weight) results in a sufficiently important association of the polypeptide with the skin during the period of current passage. Much less significant effects are realized by the cathodal iontophoresis of poly-anions due to the difficulty of 'pushing' negative ions into an already negatively-charged membrane.

Administration, Cutaneous↗
PubMed1985

Importance of the pacing mode in the initiation of ventricular tachyarrhythmia in a canine model of chronic myocardial infarction.

The use of unipolar anodal or bipolar pacing, as compared with unipolar cathodal pacing, purportedly increases the likelihood of inducing inadvertent ventricular fibrillation in susceptible patients. In this study, the ability to initiate sustained ventricular tachycardia or fibrillation with unipolar cathodal, unipolar anodal and bipolar pacing modes was compared using programmed ventricular stimulation at 82 subendocardial periinfarction sites in 11 dogs with chronic myocardial infarction. The late diastolic excitability threshold was significantly higher and the ventricular refractory period was significantly shorter (p less than 0.001) with anodal pacing (mean 0.62 mA, 156 ms, respectively) than with pacing in either the cathodal (0.12 mA, 174 ms) or the bipolar (0.13 mA, 173 ms) mode. At a current intensity twice that of the excitability threshold, the introduction of one or two extrastimuli induced ventricular tachycardia and ventricular fibrillation comparably among the three pacing modes. However, when three extrastimuli were used, ventricular fibrillation was induced with anodal pacing twice as frequently (50 [61%] of 82 sites) as with either of the other two pacing modes (each 23 [28%] of 82 sites, p less than 0.001), whereas the induction of ventricular tachycardia remained comparable with anodal pacing (15 [18%] of 82 sites) and cathodal and bipolar pacing (each 14 [17%] of 82 sites). Furthermore, a similarly high incidence of inducibility of ventricular fibrillation was observed with both cathodal pacing (56 [68%] of 82 sites) and bipolar pacing (40 [49%] of 82 sites) when an increased current equal to twice the anodal excitability threshold (1.23 mA) was used.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

Control of electrochemical reactions at the capillary electrophoresis outlet/electrospray emitter electrode under CE/ESI-MS through the application of redox buffers.

It was found that combining capillary electrophoresis (CE) and electrospray ionization mass spectrometry (ESI-MS) overlays two controlled current techniques to form a three-electrode system (CE inlet, CE outlet/ES emitter, and MS inlet electrodes) in which the CE outlet electrode and the ES emitter electrode were shared between the CE and the ESI-MS circuits. Depending on the polarities and magnitudes of the voltages at the CE inlet, CE outlet/ES emitter, and MS inlet electrodes, the nature of the two redox reactions at the shared electrode was the same or different (both reduction, both oxidation, or one oxidation and the other reduction). Several redox buffers were introduced for controlling electrochemical reactions at the shared electrode. By reacting at this electrode, redox buffers were able to maintain electrode potentials below the onset of water electrolysis, thereby eliminating gas bubble formation and/or pH drift. The volume of the gas generated due to water electrolysis was used to quantitate water oxidation or reduction at this electrode. Two types of redox buffers were used. A reactive electrode with an oxidation potential below that of water was used as the electrode under anodic conditions. Also, a reactive compound with a redox potential below that of water was added to the CE and/or ESI running buffer. When the shared electrode was the anode of both CE and ESI-MS circuits, the use of iron or etched and sanded stainless steel (ss) wire, instead of platinum wire, suppressed bubble formation at the shared electrode. Under these conditions, corrosion of the Fe wire and formation of Fe2+ replaced oxidation of water, eliminating O2 gas bubble and H+ formation. When mixtures of peptides were analyzed, iron adducts of peptides were observed. For a fresh wire, however, the intensities of adduct ions were less than 3% of the protonated molecules. After a few days of operation, the intensities of the adduct ions increased to approximately 50%, due to rust formation on the Fe wire. On-column rinsing with a 40% solution of citric acid rejuvenated the Fe wire and reduced the adduct peak intensities to less than 3%. Unmodified ss wire did not quench bubble formation, which was attributed to its passivated surface. When Fe, ss, and Pt wires were used as the shared electrode under forward polarity CE and positive ESI mode, where the shared electrode acted as a cathode with respect to CE inlet and as an anode with respect to MS inlet, reduction of water at the cathodic end of the electrode and, in the case of ss and Pt wires, oxidation of water at the anodic end of the shared electrode produced a significant amount of bubbles. Under these conditions, however, a buffer containing 50 mM p-benzoquinone completely suppressed both cathodic reduction and anodic oxidation of water for CE currents up to 4 microA. Reduction of p-benzoquinone at the cathodic end of the shared electrode to hydroquinone, and oxidation of this hydroquinone at the anodic end of the electrode, replaced reduction and oxidation of water, eliminating bubble formation. A 0.1% acetic acid solution saturated with I2 was also found to suppress bubble formation at the cathode for CE currents up to 3 microA; however, strong iodine adduct ions were observed under CE/ESI-MS when a mixture of peptides was analyzed. The application of iron as an in-capillary electrode for the analysis of a peptide mixture and a protein digest demonstrated a high separation efficiency similar to when hydroquinone was used as a redox buffer.

Journal Article↗
PubMed2003

Oxygen is electroreduced to water on a "wired" enzyme electrode at a lesser overpotential than on platinum.

The first enzyme-based catalyst that is superior to platinum in the four-electron electroreduction of oxygen to water is reported. The smooth Pt cathode reached half and 90% of the mass transport-limited current density at respective overpotentials of -0.4 and -0.58 V in 0.5 M sulfuric acid, and only at even higher overpotentials in pH 7.2 phosphate buffer. In contrast, the smooth "wired" bilirubin oxidase cathode reached half and 90% of the mass transport-limited current density at respective overpotentials as low as -0.2 and -0.25 V. The mass transport-limited current density for the smooth "wired" enzyme cathode in PBS was twice that with smooth Pt in 0.5 M sulfuric acid. Under 1 atm O2 pressure, O2 was electroreduced to water on a polished carbon cathode, coated with the "wired" BOD film, in pH 7.2 saline buffer (PBS) at an overpotential of -0.31 V at a current density of 9.5 mA cm-2. At the same overpotential, the current density of the polished platinum cathode in 0.5 M H2SO4 was 16-fold lower, only 0.6 mA cm-2.

Basidiomycota↗
PubMed2002

Nanocrystalline-TiO2-Pt photo-electrochemical cells--UV induced hydrogen evolution from aqueous solutions of alcohols.

Addition of a Pt cathode in electrical contact with a thin nanocrystalline TiO2 film gives a photo-electrochemical cell (PEC) which will, under band-gap illumination, generate hydrogen from a range of aliphatic alcohols. When the TiO2 film is irradiated in contact with 0.1 M HCl in 50%, v/v MeOH-H2O in the absence of a Pt cathode phiH2 = 0.046; in the presence of a Pt cathode the hydrogen generation yield is increased to phiH2 = 0.193. In the absence of a Pt cathode hydrogen yields are independent of the thickness (and hence optical absorbance) of the TiO2 film and phiH2 falls with increasing film thickness, indicating a surface controlled reaction. In the presence of a Pt cathode hydrogen yields increase linearly with absorption efficiency and phiH2 remains constant. In the presence of 0.01 M HCl hydrogen evolution from the PEC occurs at both the TiO2 surface (30%) and at the Pt surface (70%), while in the presence of 0.01 M NaOH hydrogen evolution is exclusively from the TiO2 surface. Provided the total ion concentration, I, is kept constant, quantum yields as a function of pH across the range 2-12 take one of two values depending upon whether the solution is acidic or alkaline, ie. for I = 0.01 M, at pH 2-6 phiH2 = 0.112 (+/- 0.007), and at pH 8-12 phiH2 = 0.029 (+/- 0.003). Studies with a series of chloro and methyl substituted alcohols suggest that the stability of the alcohol anion is an important factor in determining the efficiency of the alcohol as a sacrificial electron donor. Quantum yields for H2 evolution of ca. 30%, can be obtained.

Journal Article↗
PubMed1984

Perpendicular orientation and directional migration of amphibian neural crest cells in dc electrical fields.

The behavior of cultured neural crest cells of Ambystoma mexicanum and Xenopus laevis in dc electrical fields was studied. In fields of 1-5 V/cm, isolated or confluent cells retract both their anode- and cathode-facing margins. Subsequently, the cells elongate, with protrusive activity confined to their narrow ends. In larger fields (greater than or equal to 5 V/cm), protrusions form on the cathode-facing sides of the perpendicularly oriented cells. The cells then begin migrating laterally, perpendicular to their long axes, towards the cathode. We suggest that the perpendicular alignment and cathode-directed migrations result from cytoskeletal changes mediated by modified ion fluxes through the anode-facing (hyperpolarized) and cathode-facing (depolarized) cell membranes. The breaking of cellular confluence in response to dc electric fields is also discussed.

Ambystoma↗
PubMed2005

Responses of rabbit retinal ganglion cells to electrical stimulation with an epiretinal electrode.

Rational selection of electrical stimulus parameters for an electronic retinal prosthesis requires knowledge of the electrophysiological responses of retinal neurons to electrical stimuli. In this study, we examined the effects of cathodal and anodal current pulses on the extracellularly recorded responses of OFF and ON rabbit retinal ganglion cells (RGCs) in an in vitro preparation. Current pulses (1 msec duration), delivered by a 125 microm electrode placed on the inner retinal surface within the receptive field of a RGC, produced both short-latency (< or =5 msec) and long-latency (8-60 msec) responses. The long-latency responses, but not the short-latency responses, were abolished upon application of the glutamate receptor antagonists CNQX and NBQX, thus indicating that the long-latency responses of RGCs are due to activation of presynaptic neurons in the retina. The latency of the long-latency response depended upon the polarity of the stimulus. For OFF RGCs, the average latency was 11 msec for a cathodal stimulus and 24 msec for an anodal stimulus. For ON RGCs, the average latency was 25 msec for a cathodal stimulus and 16 msec for an anodal stimulus. The threshold current also depended upon the polarity of the stimulus, at least for OFF RGCs. The average threshold current for evoking a long-latency response in OFF RGCs was 10 microA for a cathodal stimulus and 21 microA for an anodal stimulus. In ON RGCs, the average threshold current was 13 microA for a cathodal stimulus and 15 microA for an anodal stimulus.

Action Potentials↗
PubMed1982

A sandwich electrode for multi-gas analysis: a prototype.

A prototype composite electrode consisting of a metallized membrane "outer" cathode, and a conventional "inner" silver disc cathode, both sharing the same electrolyte, is described. Preliminary results indicate that the metallized membrane will act as an oxygen filter, allowing anaesthetic gases such as nitrous oxide, to pass through to the second (inner) cathode, where they may be reduced. Linear relationships exist for oxygen concentration and metallized membrane current; and for nitrous oxide concentration and the second cathodic current. Extension of this technique to measure both halothane and nitrous oxide on the second cathode, simultaneously with oxygen on the metallized membrane, is discussed.

Electrodes↗
PubMedDate not supplied

Reduced skin hyperemia during tap water iontophoresis after intake of acetylsalicylic acid.

Skin microcirculation and skin temperature of 10 healthy subjects (6 men and 4 women, 20-44 yr of age) without any vascular diseases were registered when a thermoindifferent tap water iontophoresis was applied. The aim of this controlled study was to evaluate the development of skin hyperemia after the intake of 500 mg of acetylsalicylic acid (ASA). The measurement was conducted by laser-Doppler flowmetry on the proximal forearm. The skin temperature was measured before and after the treatment by an infrared thermometer. In all persons there was an intense erythema on the side of the cathode and only a modest one on the side of the anode. Without ASA preliminary treatment, the cutaneous flow showed an increase of 106% at the anodal side and that of 834% at the cathodal side (P < 0.001). After ending tap water iontophoresis, the skin temperature increased more on the cathode side than on the anode side (P < 0.001). After the intake of 500 mg ASA, the increase of the flow was 78% at the anode and 88% at the cathode. The comparison of the skin microcirculation did not show any differences at the anodal side when acetylsalicylic acid was taken before, but a strong suppression of the galvanic erythema at the cathodal side was observed after the intake of ASA. There is a direct influence of acetylsalicylic acid on the induction of the neurogenic inflammation caused by a galvanic erythema. The intensity of the induced erythema correlates with the analgesic effects of constant current treatment. An attenuation of the electrotherapeutic analgesia is possible.

Adult↗
PubMed1973

Hormonal control of isoperoxidases in lentil embryonic axis.

Detachment of the cotyledons from the lentil (Lens culinaris Med.) embryonic axis causes in the latter an increase in total peroxidase activity which is shown to be due to enhancement of specific cathodic isoperoxidases. Kinetin treatment of attached or detached axes promotes activity of essentially the same cathodic isoperoxidases. In addition kinetin enhances the activity of two anodic peroxidases and represses specifically that of a cathodic one. Abscisic acid inhibits the production of all isoenzymes in the presence or absence of kinetin. Cytokinin and abscisic acid actions are discussed in relation to the nature of a wounding hormone and the role of natural inhibitors in cotyledons during germination. Indoleacetic acid stimulates the activity of certain isoenzymes which are also stimulated by kinetin, whereas in others the effects of the two hormones are different. Specific inverse effects of indoleacetic acid and kinetin are demonstrated on the two most cathodic isoperoxidases. Indoleacetic acid-kinetin interactions on the cathodic isoperoxidases have been found in the literature and are discussed as a possible mechanism for explaining interactions of the two regulators on growth and other physiological processes.

Journal Article↗