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1.
S-Methyl-L-cysteine was actively metabolized in Chinese cabbageand carbon from its methyl group was distributed into both thesoluble and insoluble fractions. The high incorporation of 14Cfrom the methyl group into the insoluble fraction after administeringof S-methyl-L-cysteine-14CH3, and our previous results thatS-methyl-L-cysteine is demethylated to give cysteine, suggestthat S-methyl-L-cysteine might act as a methyl donor in Chinesecabbage. To obtain evidence for this possibility, incorporationof the methyl-14C of S-methyl-L-cysteine into methyl estersof pectic substances was investigated. Most of the 14C incorporatedinto pectic substances was liberated by treatment with dilutealkali and pectin esterase. The results show that S-methyl-L-cysteineacts as a methyl donor to form pectin ester. (Received October 12, 1971; )  相似文献   

2.
The levels of purine and pyrimidine nucleotides in suspensioncultures of Catharanthus roseus were determined 24 h after stationary-phasecells were transferred to fresh complete (‘+Pi’)or phosphate-deficient (‘–Pi’) Murashige-Skoogmedium. The levels of ATP, GTP, UTP and CTP were from approx.3 to 5-fold greater in the cells grown in ‘+Pi’medium than in the cells grown in ‘–Pi’ medium.The levels of almost all other nucleotides were slightly higherin the cells in ‘+Pi’ medium. The rates of de novoand salvage biosynthesis of purine and pyrimidine nucleotideswere estimated from the rates of incorporation of radioactivityfrom [14C]formate, [2–14C]glycine, NaH14CO3, [6–14C]orotate,[8–14C]adenine, [8–14C]adenosine, [2–14C]uraciland [2–14C]uridine. The results indicated that the activityof both the de novo and the salvage pathway was higher in thecells in ‘+Pi’ medium than in the cells in ‘–Pi’medium. The rate of degradation estimated from the rate of releaseof 14CO2 from labelled purines and pyrimidines indicated thatdegradation of uridine was significantly reduced in the cellsin ‘+Pi’ medium, but no significant difference wasfound in the degradation of adenine, adenosine and uracil. Thepossible role of Pi in the control of the biosynthesis of nucleotidesand in the degradation of uridine is discussed. Catharanthus roseus, Madagascar periwinkle, suspension culture, inorganic phosphate, nucleotides, purines, pyrimidines, biosynthesis, degradation  相似文献   

3.
Sixty-eight per cent of nuclei in the cells of the upper fourlayers of carrot slices treated with heat-killed conidia ofBotrytis cinerea for 6 h followed by inoculation with live sporesfor 18 h, migrated to the cell face nearest to the treated surface,compared with 46 per cent in cells of control slices showinga wound-healing response only. Nucleolar volumes in the surfacecell layers of control slices increased from a mean of 1.0 µm3to 3.8 µm3 over 24 h, and in ‘induced’ slicesto 7.28 µm3. Using a 40 min pulse of [5–3H]uracil,there was an increase within 15 h of slicing in the number oflabelled nuclei in cells from control slices undergoing healing.Within 8 h after treatment of slice surfaces with heat-killedconidia, there was an accelerated incorporation of label into‘nuclear’ RNA. Slices from roots cold-stored for12 months failed to show an induction response and nucleolarvolumes did not increase more than in control slices. Theseresults are discussed in relation to active defence mechanismsin plant tissue. Botrytis cinerea, carrot, induced resistance, nuclear migration, nucleolar volume, RNA incorporation  相似文献   

4.
ERRATA     
Effects of coupled solute and water flow in plant roots withspecial reference to Brouwer's experiment. Edwin L. Fiscus. p. 71 Abstract: Line 3 delete ‘interval’ insert‘internal’. p. 73 Materials and Methods: line 6: delete ‘diversion’ insert ‘division’ line 9 equation should read Jv=Lp PRT(C0C1). 74 Last line of figure legend: 10–1 should read 10–11. 75 Line 11: delete ‘seems’ insert ‘seem’. le 1 column heading—106 should read 1011. 77 delete ‘...membrane in series of...’ insert ‘membranein series or...’ Delete final paragraph.  相似文献   

5.
Nitrate provision has been found to regulate the capacity forChara corallina cells to take up nitrate. When nitrate was suppliedto N sufficient cells maximum nitrate uptake was reached after8 h. Prolonged treatment of the cells in the absence of N alsoresulted in the apparent ability of these cells to take up nitrate.Chlorate was found to substitute partially for nitrate in the‘induction’ step. The effects on nitrate reductionwere separated from those on nitrate uptake by experiments usingtungstate. Tungstate pretreatment had no effect on NO3uptake ‘induced’ by N starvation, but inhibitedNO3 uptake associated with NO3 pretreatment. Chloridepretreatment similarly had no effect on NO3 uptake ‘induced’by N deprivation, but inhibited NO3 uptake followingNO3 pretreatment. The data suggest that there are atleast two mechanisms responsible for the ‘induction’of nitrate uptake by Chara cells, one associated with NO3reduction and ‘induced’ by CIO3 or NO3and one associated with N deprivation. Key words: Nitrate, Chlorate, Chara corallina, Induction  相似文献   

6.
Differences in premature leaf abscission and in visible steminjury in genetic lines of poplar followed continuous fumigationswith air pollutant levels of SO2 (90–100 nl l–1)and O3 (70–80 nl l–1) either separately or together.The clones used were: Populus deltoides var. missiouriensisMarsh., P. nigra cv. ‘italicd’ L., and the hybridsP. nigra cv. ‘italica’ xP. deltoides (He-X/3) andP. nigra cv.‘italica’ x P. nigra cv. ‘Serres’(He-K/7). While most leaf abscission occurred within 20 d fromthe start of fumigation, stem lesions (intumescences), appearedonly after 72 d. Their anatomical characteristics include theformation of lysigenous aerenchyma in the lower parts of theintumescence, the sloughing of superficial cells from the injuredarea, and the development of crystalline formations on the surfaceof the lesions. P. deltoides exhibited the least morphologicalresponse to the gases. Ethylene released from fumigated leaves was determined at thesame gas concentration of SO2 (100 nl l–1), O3 (75 nll–1) and their mixture. Leaves of P. deltoides consistentlyshowed the lowest ethylene production after the gas treatments.P. ‘italica’ production was higher but was littlealtered by the treatments. The two hybrids He-X/3 and He-K/7showed the greatest increases in ethylene evolution with time.With He-K/7 exposed to the gas mixture the production of ethylenedecreased after the initial sharp rise during days 1–2,and reflected the considerable leaf damage observed after day3. The results suggest that sensitivity to air pollution, (as shownby leaf abscission and the formation of stem intumescences)can be correlated with the level of pollutant-induced ethyleneevolution from leaves. Initially high levels could induce abscission,whilst prolonged production could be responsible for intumescenceinitiation. The discussion proposes a series of events fromSO2 and/or O3 entry into the leaf and the physiological reasonsfor the clonal differences. Key words: Sulphur dioxide, ozone, ethylene, poplar, leaf abscission, stem lesions  相似文献   

7.
The effects of exposure of up to 2 h with sulphur dioxide ona range of plant species was observed by measuring changes inthe rate of net photosynthesis under closely controlled environmentalconditions. Ryegrass, Lolium perenne ‘S23’ was thespecies most sensitive to SO2; significant inhibition was detectedat 200 nl l–1. Fumigations at 300 nl l–1 also inhibitedphotosynthesis in field bean (Vicia faba cv. ‘Three FoldWhite’ and ‘Blaze’) and in barley (Hordeumvulgare cv. ‘Sonja’). No effect was detected inwheat (Triticum aestivum cv. ‘Virtue’) at concentrationsup to 600 nl l–1 SO2, or in oil-seed rape (Brassica napuscv. ‘Rafal’) except at 800 nl l–1 SO2). Recoverycommenced immediately after the fumigation was terminated andwas complete within 2 h when inhibition had not exceeded 20%during the SO2 treatment. Key words: Sulphur dioxide, short-term fumigation, photosynthesis  相似文献   

8.
A microsomal flavonoid 3'-hydroxylase (F3'H) catalyzing themetabolism of naringenin to eriodictyol in Citrus sinensis (L.)Osbeck cv. ‘Hamlin’ cell suspension cultures wasshown to be a cytochrome P450 enzyme. This reaction requiredO2 and NADPH and was inhibited by CO, with partial reversalof CO-inhibition by light at 450 nm. Cytochrome P450 contentranged from 10–20 pmol (mg microsomal protein)–1.The F3'H reaction was shown to be linear in regard to proteinconcentration between 2.5 and 25 µg of microsomal protein.The optimum pH for the reaction was 7.4–7.6 and the temperatureoptimum was between 30 and 37°C. The apparent Km and Vmaxfor naringenin were 24 µM±3.2 and 81.4±7.9pmol eriodictyol min–1 (mg protein)–1, respectively.The microsomal F3'H was also capable of forming dihydroquercetinfrom dihydrokaempferol (40 pmol min–1 (mg protein)–1)and of quercetin from kaempferol (3.25 pmol min–1 (mgprotein–1). Cytochrome c and ketoconazole were the bestinhibitors of WH activity followed by piperonyl butoxide anda-naphthoflavone. Light was shown to be an inducer of the F3'Halmost doubling the specific activity and increasing the microsomalcytochrome P450 content by 30% over that of dark grown cells.F3'H activity was also confirmed in microsomal preparationsof young (new flush) leaves from ‘Hamlin’ treesand flavedo of ‘Hamlin’ oranges, ‘Marsh’grapefruit, and ‘Lisbon’ lemon. No activity wasobserved in older, hardened leaves and albedo of all the fruittested. Initiation of embryogenesis in the ‘Hamlin’cell suspension cultures by switching from a sucrose mediumto a glycerol-based medium resulted in the down-regulation ofF3'H. 1Mention of a trademark, warranty, proprietary product, or vendordoes not constitute a guarantee by the U.S. Department of Agricultureand does not imply its approval to the exclusion of other productsor vendors that may also be suitable.  相似文献   

9.
Plants of four isolines of soyabean [Glycine max(L.) Merrill]‘Clark’, viz‘L71-920’ (maturity genecomplemente1e2e3 ), ‘L80-5914’ (E1e2e3), ‘Clark’(e1E2E3), and ‘L65-3366’ (E1E2E3), were grown inshort (12.25 h d - 1natural light) and long days (12.25 h d- 1natural light supplemented with 2.75 h d - 1low-irradianceartificial light) from first flowering to maturity in a polythenetunnel maintained at 30/24°C (day/night). Whereas therewere few differences among the isolines grown in short days,in long days the dominant alleles increased crop duration, biomassand seed yield substantially. Increases in biological and economicyield were not solely a consequence of longer crop duration:the dominant alleles also increased crop growth rate and radiationuse efficiency in long days (from 1.3 g MJ - 1total radiationine1e2e3 to 2.8 g MJ - 1inE1E2E3 ). Greater radiation use efficiencyresulted from a relatively longer leaf area duration, betterdistribution and orientation of a larger mass of leaves withinthe canopy, and smaller partitioning of assimilates to reproductivestructures. The work reveals the substantial effects of thethree lociE1 / e1, E2/ e2and E3/e3 on the response of plantgrowth, as well as development, to environment. Their relevanceto crop adaptation is discussed. Copyright 2000 Annals of BotanyCompany Glycine max(L.) Merrill, soyabean, maturity genes, flowering, phenology, growth, yield  相似文献   

10.
Five Gladiolus cultivars, namely ‘Aldebaran’, ‘BrightEye’, ‘Illusion’, ‘Manisha’ and‘Manmohan’, were exposed to 1 and 2 µg l–1sulphur dioxide to test their relative-sensitivity toleranceto the pollutant Plants were fumigated experimentally for 2h daily Foliar injury symptoms were observed first in ‘Manisha’followed by ‘Aldebaran’ and ‘Illusion’at the higher dose Photosynthetic pigments and leaf extractpH were significantly decreased, particularly in ‘Manisha’and ‘Illusion’ Overall disturbances in the plantmetabolism due to SO2 treatment led to retarded growth of plants,as evident from decreased shoot length and phytomass valuesThe order of sensitivity of the five Gladiolus cultivars toSO2 was as follows, with the greatest first Manisha, Illusion,Aldebaran, Bright Eye, Manmohan Cultivars, Gladiolus, sensitivity, sulphur dioxide, tolerance  相似文献   

11.
Removal of the blade from the leaf subtending the first flowerbud on Cyclamen persicum ‘Swan Lake’ plants causedthe petiole of that leaf to senesce, but had no effect on thegrowth of the flower peduncle in the debladed petiole's axil.A 10 mg NAA l–1 application generally had no effect onpetiole senescence, peduncle elongation or flowering date whenapplied to the cut end of the petiole after blade removal. A25 mg GA3 l–1 application or a combination of 25 mg GA3l–1 application or a combination of 25 mg GA3 l–1plus 10 mg NAA l–1 delayed petiole senescence and enhancedpeduncle elongation and subsequent flowering. No treatment significantlyaltered peduncle length at the time of flowering. Cyclamen persicum Mill, ‘Swan Lake’, tissue receptivity, flowering, GA3, NAA  相似文献   

12.
HARVEY  D. M.; GOODWIN  J. 《Annals of botany》1978,42(5):1091-1998
The effect of the ‘leafless’ mutation (in whichtendrils replace leaflets and the stipules are reduced to avestigial form) upon foliage area, photosynthetic net CO2 uptakepotential, dry matter production and seed yield in Pisum sativumwas studied by comparing two near-isogenic lines of genotypeafafstst and ++++. The mutation is of potential agronomic valuein that it offers improved lodging resistance, crop drying andharvester throughput. In the conventional phenotype the total foliage area of themain axis attained a plateau (456 cm2) at day 56 from seedlingemergence, whereas corresponding values for the ‘leafless’mutant showed a total area of 208 cm2 at day 68 with no indicationof a plateau. The agronomic consequence of this is discussed.During the vegetative phase of the plant the maximum CO2 uptakepotential in the fully expanded conventional leaf was 8·5mg CO2 leaf–1 h–1 and in the ‘leafless’mutant this value was 7·0 mg CO2 leaf–1 h–1.For most ‘leaves’ of the latter phenotype this valuewas between 30 and 60 per cent less than for their conventionalcounterpart. There was a consistently higher photosyntheticpotential per unit area in tendrils of the ‘leafless’mutant than in leaflets of the conventional phenotype. The respectivemean specific values for the two phenotypes were 53 and 37 mgCO2 dm–2 h–1. The problem of obtaining a meaningfulsurface area value for tendrils is discussed and the cylindricalnature of tendrils is taken into account. The ‘leafless’ mutant consistently accumulated 50per cent less dry matter than did conventional plants in theperiod from seedling emergence to anthesis and yield of maturedry seed per plant showed a reduction of 50 per cent both inseed number and total seed weight. The implications for future breeding and selection programmesaimed at haulm reduction are discussed in relation to evaluatingthe ability of the background genotype to produce adequate tendrilsin the presence of afafstst. Triticum aestivum, wheat, callus culture, organogenesis  相似文献   

13.
The theory and practice of applying the thermodynamics of irreversibleprocesses to mass-flow theories is presented. Onsager coefficientswere measured on cut and uncut phloem and cut xylem strandsof Heracleum muntegazzimum. In 0.3 N sucrose + 1 mN KC1 theyare as follows. In phloem, LEE = 5 ? 10–4 mho cm–1,LpE = 9 ? 10–6 cm3 s–1 cm–2 volt–1 cm,and LPP = 0.16 cm3 s–1 cm–2 (J cm–3)–1cm. In uncut phloem strands LEE is about 1 ? 10–3 mhocm–1. In xylem in 2 x 10–3 N KCI, Lpp = 50 to 225,LPE = 2 ? 10–4, and LEE = 4 ? 10–3. The measurementsare tentative since the blockage of the sieve plates is an interferingfactor, but if they are valid they lead to the conclusion thatneither a pressure-flow nor an electro-kinetic mechanism envisaginga ‘long distance’ current pathway can be the majormotive ‘force’ for transport in mature phloem. Measurementsof biopotentials along conducting but laterally detached phloembundles of Heracleum suggest, nevertheless, that there may bea small electro-osmotic component of at least 0.1 mV cm–1endogenous in the phloem.  相似文献   

14.
Methylamine1 is taken up rapidly by disks cut from fronds ofUlva rigida (‘Ulva lactuca’) and can be accumulatedat concentrations several hundred times greater than those inthe bathing medium. At pH 8.0 (the pH of sea-water) the relationshipbetween influx and concentration is normally linear up to 0.1–0.3mM, followed by a second, less steep linear phase, the slopeof which decreases or increases with decreasing or increasingexternal pH. When pH is greater than 9.0, however, net uptakesoon ceases. Methylamine influx is greatly reduced at low temperature,by low concentrations of ammonia and, depending on the lengthof storage of the material, by darkness. Influx is also greatlyreduced when disks are pretreated in solutions containing ammoniaand to a much lesser extent when they are pretreated in methylamine,imidazol or nitrate. Methylamine influx lowers intracellularK+, increases Cl and has no effect on Na+. We suggestthat the first linear phase of influx versus concentration reflectsthe operation of an amine cation porter that is rate-limitedby diffusion of CH3NH3+ through the external unstirred layer,and that the second phase is due to diffusion of CH3NH2 intothe tissue.  相似文献   

15.
Barley (Hordeum vulgare L., cvs Golf, Mette, and Laevigatum)was grown under nitrogen limitation in solution culture untilnear maturity. Three different nitrogen addition regimes wereused: in the ‘HN’ culture the relative rate of nitrate-Naddition (RA) was 0·08 d–1 until day 48 and thendecreased stepwise to, finally, 0·005 d–1 duringgrain-filling; the ‘LN’ culture received 45% ofthe nitrogen added in HN; the ‘CN’ culture was maintainedat RA 0·0375 d–1 throughout. Kinetics of net nitrateuptake were measured during ontogeny at 30 to 150 mmol m–3external nitrate. Vmax (which is argued to reflect the maximuminflux rate in these plants) declined with age in both HN andLN cultures. A pronounced transient drop was observed just beforeanthesis, which correlated in time with a peak in root nitrateconcentration. Similar, but less pronounced, trends were observedin CN. The relative Vmax (unit nitrogen taken up per unit nitrogenin plants and day) in all three cultures declined from 1·3–2·3d–1 during vegetative growth to 0·1–0·7d–1 during generative growth. These values are in HN andLN cultures 15- to more than 100-fold in excess of the demandset by growth rates throughout ontogeny. Predicted balancingnitrate concentrations (defined as the nitrate concentrationrequired to support the observed rate of growth) were below6·0 mmol m–3 in HN and LN cultures before anthesisand then decreased during ontogeny. In CN cultures the balancingnitrate concentration increased during grain-filling. Apartfrom the transient decline during anthesis, most of the effectof ageing on relative Vmax can be explained in terms of reducedcontribution of roots to total biomass (R:T). The loss in uptakeper unit root weight is largely compensated for by the declinewith time in average tissue nitrogen concentrations. The quantitativerelationships between relative Vmax and R:T in ageing plantsare similar to those observed for vegetative plants culturedat different RAs. The data support the contention that the capacity for nitrateacquisition in N-limited plants is under general growth control,rather than controlled by specific regulation of the biochemicalpathway of nitrate assimilation. Key words: Barley, nitrogen concentration, root: total plant biomass ratio, Vmax  相似文献   

16.
The rates of CO2 incorporation into the epidermis of C. communiswere linear and were similar during the completion of opening(2 h) and closing (1 h) movements of stomata. The kinetics of14C turnover between metabolites and the rates of ‘leakage’of metabolites were determined for opening and closing movements.When stomata were opening there was a slow turnover of 14C frommalate chiefly into sugars. Upon stomatal closure 14C was initiallymainly in sugars, malate, and sugar phosphates. Thereafter,there was a slight loss of label from sugar phosphates witha corresponding increase in malate. Starch became labelled duringopening and closing movements. Rates of incorporation of CO2found in the ‘leakage’ fraction were greatest whenstomata were opening. Of the labelled compounds Most‘from the tissue, malate was the most highly labelled whetherstomata were opening or closing. Although interpretation of the turnover patterns is difficultwithout knowledge of pool sizes for the metabolites it is suggestedthat a pool of sugars exists within the guard cells, which havefairly direct and reversible access to carbon from starch andmalate. The implications of loss of malate from guard cellsduring stomatal opening and closing are discussed.  相似文献   

17.
Guerrero et al (1994) promote Tauti's equation, rate = a exp(b temp), as simple to fit by log conversion (which may be formallyinappropriate), empirically adequate, and having ‘appropriatebiological characteristics’. No function is justifiablefrom reductionist theories, but Belehrádek's, rate =a (temp – T0)b, with b fixed for the taxon of interest,fits equally well, and singularly distinguishes differencesattributable to temperature adaptation (T0, often misunderstoodas ‘biological zero’), and to size or other species-dependentproperties (a).  相似文献   

18.
Zoea I larvae of the brown shrimp Crangon crangon (Decapoda)were exposed to varying levels of UV radiation in a sunshinesimulator. ‘Short-term exposures’ (0–8 h)were used to determine the highest UV dose with no significanteffect (NOEC; defined by limit of detection) and the lethaldose of 10 and 50% mortality (LD10 and LD50). Crangon crangonshowed a relatively high sensitivity to UVB radiation (NOEC= 10 kJ m–2, LD10 = 15 kJ m–2, LD50 = 24 kJ m–2)compared to other crust-acean species. LD values (1997–1998)showed no adaptation to seasonal light regimes. ‘Long-termexposures’ (0–10 days) were carried out to assessthe range where the ‘law of reciprocity’ is valid.The larvae were exposed to UV levels of 0.2, 0.4 and 0.7 J m–2for appropriate time intervals, always cumulating in a sublethaldose of 5 kJ m–2 day–1. Results reflect a possiblethreshold (0.2–0.4 J m–2 UVB) in the effect of thedifferent UVB doses used; thus, a proportional relationshipof intensity and exposure time can only be shown at UVB levelsabove this threshold intensity.  相似文献   

19.
The layer of daytime concentration of Calanus ponticus (VC andVI C) performing daily vertical migrations and the layer of‘winter stock’ aggregation are confined to the depthof maximal gradient of the main pycnocline under an unusuallysharp oxycline. The concentration layer thickness ranges from2 to 20–30 m and the Calanus concentration in it is >250ind. m–3, sometimes being 3500 ind. m–3 and evenmore. The population in the concentration layer is divided intotwo ecological groups: I, feeding and migrating specimens ofcopepodite stages V and VI, their body lipid contents being25–60 µg min.–1; and II, non-feeding and non-migratingspecimens of copepodite stage V, their body lipid contents being100–150 µg ind.–1. The relationship with oxygenconcentration was studied in both ecogroups. The experimentsshow that specimens of ecogroup II can exit at an oxygen concentrationof 0.06 ml 1–1, but at such concentration falling intoanabiosis. They die at 0.04 ml O2 1–1. Estimates of respirationof the group II specimens (‘winter stock’) showthat lipids they store are sufficient for 7 months' survival.Depth of Calanus concentration is determined by water densityrather than concentration of oxygen.  相似文献   

20.
Valentincic  Tine 《Chemical senses》1991,16(3):251-266
Feeding behavior of the brittle star Ophiura ophiura includesorienting posture, orienting movements, arm ‘walking’,changing the direction of ‘walking’ arm coilingand ingestion. All sequential behavior patterns were releasedor enhanced by single low-molecular-weight compounds. Stimuliwhich released ‘walking’ behavior at high concentrations(10–4 M) in all the test animals are listed in decreasingorder of sensitivity: sarcosine, glycine, urea, L-valine, L-leucine,L-methionine, L-homocysteine, L-norvaline, L-norleucine, L-threonine,L-serine, S-methyl-L-cysteine, L-proline. Threshold values forsingle amino acids were as much as 100 times different in differentindividuals and ranged from 3 x 10–9 to 3 x 10–7M for the most effective stimulus, sarcosine, and from 10–6to 10–4 M for proline. Above 10–5 M, only L-prolineregularly released a second behavior pattern, the arm coilingresponse, which temporarily inhibited the ‘walking’behavior. Behavioral thresholds for the ‘walking’behavior for L(+)-lactate and L-alanine were higher than thosefor the orienting movements. Thyoglycolic acid and ß-alaninereleased tube feet walking, which is not part of the feedingbehavior. Structure—activity comparisons were studied at estimated10–5 M concentrations. Gycline, sarcosine, L-valine, L-norvaline,L-leucine, L-isoleucine, DL-norleucine and DL-homocysteine releasedarm ‘walking’ behavior in more than 75% of all thetests. With the exceptions of S-methyl-and S-ethyl-cysteine,and glycine methylester, derivatives of amino acids were noteffective behavioral stimuli in Ophiura ophiura. L-Isomers ofvaline and leucine regularly stimulated the ‘walking’behavior while their D-isomers were effective in some testsand ineffective in others. Acetylcholine iodide, acetyl-ß-methylcholine chloride and choline phosphate chloride regularly released‘walking’ behavior at concentrations above 10–5M.  相似文献   

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