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1.
本文旨在研究福建闽南地区汉族和畲族指长比(R)的特点。随机选择福建闽南地区汉族506例(男性173例,女性333例),畲族450例(男性231例,女性219例),采用体质测量法,测量并计算左右侧6项指长比(R2/3、R2/4、R2/5、R3/4、R3/5、R4/5)。福建闽南地区汉族和畲族左、右侧指长比均呈R2/3<R2/4<R3/4<R2/5<R4/5<R3/5的趋势;汉族女性指长比左侧R2/3、R2/4、R2/5、R3/4、R3/5和右侧R2/3、R2/4、R2/5高于汉族男性(P<0.05);畲族女性指长比左侧的R2/3、R2/4、R2/5和右侧R2/3、R2/4高于畲族男性(P<0.05);畲族男性指长比左、右侧R2/3、R2/4、R2/5、R3/5、R4/5高于汉族男性(P<0.05);畲族女性指长比左侧R2/3、R2/4和右侧R2/3、R2/4、R2/5、R4/5高于汉族女性(P<0.05)。同民族不同性别两侧R2/4百分比分布差异有统计学意义,不同民族同性别右侧R2/4百分比分布差异有统计学意义。福建闽南地区汉族和畲族指长比存在性别、侧别的不同,与其他地区、族群也存在差异。 相似文献
2.
Abstract The utilization of NO− 3 , NO− 2 and NH+ 4 was studied in whole filaments and isolated heterocysts of Anabaena 7120 (ATCC27893). NO− 3 - and NO− 2 -uptake were detectable in whole filaments but not in heterocysts, whereas NH+ 4 -uptake was detectable in both. Activity of NO− 3 -reductase was present in cell-free extracts of whole filaments but not of heterocysts, whereas activities of NO− 2 -reductase and glutamine synthetase were present in both. NO− 3 -uptake and reductase activities could not be induced in heterocysts even after prolonged incubation in NO− 3 medium. It is suggested that NO− 3 -metabolism in heterocysts is impaired due to a selective and irreversible loss of NO− 3 -uptake and reductase systems resulting in the abolition of competition for molybdenum cofactor (Mo-Co) and reductant between nitrogenase and NO− 3 -reductase, and an increase in glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase levels. 相似文献
3.
Carbon dioxide induces increases in guard cell cytosolic free calcium 总被引:10,自引:0,他引:10
Alex A.R. Webb Martin R. McAinsh Terry A. Mansfield Alistair M. Hetherington 《The Plant journal : for cell and molecular biology》1996,9(3):297-304
The hypothesis that increases in cytosolic free calcium ([Ca2+ ]i ) are a component of the CO2 signal transduction pathway in stomatal guard cells of Commelina communis has been investigated. This hypothesis was tested using fura-2 fluorescence ratio photometry to measure changes in guard cell [Ca2+ ]i in response to challenge with 700 µl l−1 CO2 . Elevated CO2 induced increases in guard cell [Ca2+ ]i which were similar to those previously reported in response to abscisic acid. [Ca2+ ]i returned to resting values following removal of the CO2 and further application of CO2 resulted in a second increase in [Ca2+ ]i . This demonstrated that the CO2 -induced increases in [Ca2+ ]i were stimulus dependent. Removal of extracellular calcium both prevented the CO2 -induced increase in [Ca2+ ]i and inhibited the associated reduction in stomatal aperture. These data suggest that Ca2+ acts as a second messenger in the CO2 signal transduction pathway and that an increase in [Ca2+ ]i may be a requirement for the stomatal response to CO2 . 相似文献
4.
S. Abarzua R. Altenburger R. Callies L.-H. Grimme A. Mayer D. Leibfritz U. Schiewer 《Physiologia plantarum》1993,89(3):659-663
Over a period of several days, rhythmic changes in extracellular NH+ 4 concentration take place in cultures of the cyanobacterium Microcystis firma (Bré et Lenorm.) Schmidle, strain Gromov/St. Petersb. 398, under conditions of restricted CO2 supply and light/dark alternation. The changes are enhanced by nitrate supply. Among the various processes generating intracellular NH+ 4 (NH4 4 uptake, NO− 3 reduction, protein and amino acid degradation, photorespiration), NO− 3 reduction appears as the one most important. This can be concluded from experiments with and without nitrate and/or ammonium in the medium. In the presence of saturating CO2 , continuous light, or continuous darkness, rhythmic NH+4 4 oscillations are not induced. Studies of the incorporation of NH+ 4 nitrogen by in vivo 15 N-NMR show that if CO2 is supplied, 15 N is accumulated in several components with the following time course: in the first hour in Gln (δ), in the second hour in the α-amino groups of most nonbranched amino acids, in the third hour in γ-aminobutyric acid (GABA), Orn (δ) and Lys (ε), and in the sixth hour in Ala. Carbon limitation, however, results in accumulation of label in the amide nitrogen of glutamine only. 相似文献
5.
Eric N. Powell George M. Staff Robert J. Stanton Jr W. Russell Callender 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2001,34(2):97-118
We evaluate onshore-offshore trends in age-frequency distributions and trophic transfer efficiencies using 11 modern death assemblages off the Texas coast. Trophic transfer efficiencies within trophic levels offer little insight over that achieved by a size-frequency distribution. Production/biomass ratios will always be 1 in the fossil record. Within trophic-level estimates of paleogrowth efficiency, the ratio of paleoproduction to paleoingestion (Piglt/Iilt where i indicates the ith trophic level and lt indicates the time-averaged value) follow the expected ecological trend precisely in that paleogrowth efficiency is consistently higher in primary consumers than in predators in all 11 death assemblages. Paleoutilization efficiency, the ratio of predator paleoingestion to prey paleoproduction, I2lt°/P1glt°, may provide information on the degree of bias in the preservation of primary (1 °) and secondary (2 °) consumer trophic groups. I2lt°/P1glt° fell below 0.1 in most cold-seep and bay assemblages, indicating a large surplus of primary consumers. In sharp contrast, I2lt°/P1glt° 相似文献
6.
Juan Cabezas-Herrera María Teresa Moral-Naranjo F. Javier Campoy Cecilio J. Vidal 《Journal of neurochemistry》1997,69(5):1964-1974
Abstract: The distribution and glycosylation of acetylcholinesterase (AChE) forms in vesicles derived from sarcoplasmic reticulum of normal muscle (NMV) were investigated and compared with those from dystrophic muscle vesicles (DMV). AChE activity was similar in NMV and DMV. Most of the AChE in NMV and half in DMV were released with Triton X-100. Asymmetric (A12 ) and globular hydrophilic and amphiphilic (GH 4 , GA 4 , GA 2 , and GA 1 ) AChE species occurred in NMV and DMV, the lighter forms being predominant. The percentage of GH 4 and GA 4 decreased in DMV. A fraction of the AChE that could not be extracted with detergent was detached with collagenase. Most of the detergent-released A12 AChE from NMV and nearly half in DMV failed to bind to Ricinus communis agglutinin (RCA-I). Conversely, the collagenase-detached isoforms bound to RCA, revealing that asymmetric AChE associated with internal membranes or basal lamina differed in glycosylation. Moreover, nearly half of GA 4 AChE in DMV and a few in NMV bound to RCA. Most of the RCA-unreactive GA 4 forms in NMV come from sarcolemma. The results indicate that dystrophy induces minor changes in the distribution and glycosylation of AChE forms in internal membranes of muscle. 相似文献
7.
Root ammonium transport efficiency as a determinant in forest colonization patterns: an hypothesis 总被引:3,自引:0,他引:3
H. J. Kronzucker M. Y. Siddiqi A. D. M. Glass D. T. Britto 《Physiologia plantarum》2003,117(2):164-170
Ratios of ammonium (NH4 + ) to nitrate (NO3 – ) in soils are known to increase during forest succession. Using evidence from several previous studies, we hypothesize that a malfunction in NH4 + transport at the membrane level might limit the persistence of early successional tree species in later seral stages. In those studies, 13 N radiotracing was used to determine unidirectional fluxes and pool sizes of NH4 + and NO3 – in seedlings of the late-successional species white spruce ( Picea glauca ) and in the early successional species Douglas-fir ( Pseudotsuga menziesii var. glauca ) and trembling aspen ( Populus tremuloides ). At high external NH4 + , the two early successional species accumulated excessive NH4 + in the root cytosol, and exhibited high-velocity, low-efficiency (15% to 22%), membrane fluxes of NH4 + . In sharp contrast, white spruce had low cytosolic NH4 + accumulation, and lower-velocity but much higher-efficiency (65%), NH4 + fluxes. Because these divergent responses parallel known differences in tolerance and toxicity to NH4 + amongst these species, we propose that they constitute a significant driving force in forest succession, complementing the discrimination against NO3 – documented in white spruce (Kronzucker et al. 1997). 相似文献
8.
Azimuthal variation in nighttime sap flow and its mainly influence factors of Populus tomentosa
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《植物生态学报》1958,44(8):864
为明确毛白杨(Populus tomentosa)不同方位夜间蒸腾量(Nt)及茎干充水量(Sr)等夜间液流活动的规律, 探究不同方位Nt和Sr的主要影响因子, 该研究使用热扩散的方法监测了宽窄行模式下栽植的毛白杨茎干不同方位夜间液流, 并用图像法区分Nt和Sr。使用自动气象站和机械式张力计监测太阳总辐射(Rs, kW·m-2)、空气温度(Ta, ℃)、空气相对湿度(RH, %)、风速(v, m·s-1)、土壤水势(ψ, kPa)等环境因子。通过比较各方位的Nt和Sr等液流活动的大小情况及其与环境因子之间的相关性得到方位间夜间液流的差异性以及各方位夜间液流的主要影响因子。结果显示: 宽行距位于东侧的样树西方位的Nt和Sr均最大, 其中西方位的Sr显著大于其他3个方位; 北方位的Nt显著小于其他3个方位; 其他方位间的Nt和Sr无显著差异; 各方位夜间茎干充水量占夜间液流量的比例(Sr/Q)无显著差异。宽行距位于西侧的样树西方位的Nt和Sr亦均最大, 其中西方位的Sr显著大于东方位和南方位; 南方位的Nt最小, 显著小于西方位和北方位, 其他方位间的Nt和Sr无显著差异; 南方位的Sr/Q显著大于其他3个方位。各方位的Nt和Sr均与水汽压亏缺(VPD)有显著的正相关关系, 部分方位Nt和Sr与Ta和RH有显著相关关系, 没有任何方位Nt和Sr与v和ψ有显著相关关系。Nt和Sr方位间的差异(NtCV、SrCV)与VPD、Ta、RH、v和ψ均无显著相关关系。此外, Sr受白天的液流活动的影响显著。综上所述, 毛白杨不同方位Nt和Sr等液流活动具有较大的差异, 且西方位是优势方位; VPD是影响各方位Nt和Sr的主要气象因子。 相似文献
9.
Regulation of DOPA Decarboxylase Activity in Brain of Living Rat 总被引:4,自引:1,他引:3
Paul Cumming Hiroto Kuwabara Ariel Ase Albert Gjedde 《Journal of neurochemistry》1995,65(3):1381-1390
Abstract: To test the hypothesis that l -DOPA decarboxylase (DDC) is a regulated enzyme in the synthesis of dopamine (DA), we developed a model of the cerebral uptake and metabolism of [3 H]DOPA. The unidirectional blood-brain clearance of [3 H]DOPA ( K D 1 ) was 0.049 ml g−1 min−1 . The relative DDC activity ( k D 3 ) was 0.26 min−1 in striatum, 0.04 min−1 in hypothalamus, and 0.02 min−1 in hippocampus. In striatum, 3,4-[3 H]dihydroxyphenylacetic acid ([3 H]DOPAC) was formed from [3 H]DA with a rate constant of 0.013 min−1 , [3 H]homovanillic acid ([3 H]HVA) was formed from [3 H]DOPAC at a rate constant of 0.020 min−1 , and [3 H]HVA was eliminated from brain at a rate constant of 0.037 min−1 . Together, these rate constants predicted the ratios of endogenous DOPAC and HVA to DA in rat striatum. Pargyline, an inhibitor of DA catabolism, substantially reduced the contrast between striatum and cortex, in comparison with the contrast seen in autoradiograms of control rats. At 30 min and at 4 h after pargyline, k D 3 was reduced by 50% in striatum and olfactory tubercle but was unaffected in hypothalamus, indicating that DDC activity is reduced in specific brain regions after monoamine oxidase inhibition. Thus, DDC activity may be a regulated step in the synthesis of DA. 相似文献
10.
Relation of light and nitrogen source to growth, nitrate reductase and glutamine synthetase activity of jack pine seedlings 总被引:5,自引:0,他引:5
Two-month-old jack pine ( Pinus banksiana Lamb.) seedlings were placed in a greenhouse where both nitrogen source and light level were varied. After 4 months, whole seedling biomass, leaf biomass and relative growth rate were greatest in seedlings grown with NH+ 4 /NO/NO− 3 -N and full light (FL) and least in seedlings grown with NO − 3 -N and low light (LL). NO − 3 -seedlings grown under full light and NH+ 4 /NO− 3 -seedlings grown under low light were approximately equal. This indicates that the extra carbon costs of assimilating only NO− 3 -N were similar to the reduction of carbon fixation resulting from a 50% decrease in photon flux density. Percentage and total nitrogen content of needles were greater in seedlings grown under low light independent of nitrogen fertilization. Percentage and total nitrogen content of roots were higher under low light and lower when fertilized with NO− 3 .
Nitrate reductase (NR) activity was higher in roots than in needles, while glutamine synthetase (GS) activity was higher in needles than in roots. Low light resulted in decreased NR activity (mg N)−1 in needles, but not in roots. However, no nitrate was detected in the needles in any treatment. GS activity, on the other hand, was greater under low light in both needles and roots. GS activity in needles is most likely involved with the reassimilation rather than the initial assimilation of ammonium. Some implications of these shifts in enzymatic activity for ecological phenomena in forests are discussed. 相似文献
Nitrate reductase (NR) activity was higher in roots than in needles, while glutamine synthetase (GS) activity was higher in needles than in roots. Low light resulted in decreased NR activity (mg N)
11.
John D. Tjepkema 《Physiologia plantarum》1997,99(4):648-652
Preliminary studies have indicated that after addition of C2 H2 there is a rapid decline in nitrogenase activity in the nodules of Datisca glomerata . The present work was undertaken to determine whether (1) there is also a decline in respiration and (2) the decline is associated with the cessation of ammonia production. The rates of C2 H4 and CO2 evolution by nodulated root systems of Datisca were measured as a function of time after exposure to C2 H2 . The peak rate of C2 H4 evolution occurred at 30 s after C2 H2 exposure, while the rate of CO2 evolution started to decline at 60 s after exposure to C2 H2 . Incubation of nodules in a gas mixture containing Ar also caused a decline in CO2 evolution. Further, pretreatment with Ar eliminated most of the C2 H2 -induced decline in nitrogenase activity and CO2 evolution. These C2 H2 - and Ar-induced declines in Datisca nodules are more rapid than those reported in any other nodules. They are evidence that continued ammonia formation is essential for maintenance of normal nitrogenase activity in Datisca nodules. 相似文献
12.
Comparison of endogenous gibberellins in roots and shoots of elongating Salix pentandra seedlings 总被引:1,自引:0,他引:1
Gibberellins GA1 , GA8 . GA19 . GA29 . GA20 and GA56 (2-epi-GA8 ). were identified by combined gas chromatography-mass spectrometry in root extracts of elongating Salix pentandra L. seedlings. The presence of GA8 was also demonstrated for the first time in S. pentandra shoots. The levels of GA1 , GA8 , GA19 , GA20 in shoot tissue and in roots were estimated by selected ion monitoring. While the amounts of GA8 and GA19 were similar in both plant parts. the levels of the biologically active GA1 and its immediate precursor GA20 . were found to be much lower in roots than in shoots. 相似文献
13.
Na+ influx and efflux in Neurospora crassa RL21a can be studied separately to calculate net Na+ movements. In the absence of external K+ , Na+ influx was independent of the K+ content of the cells, but when K+ was present, the inhibition of Na+ influx by external K+ was higher the higher the K+ content. Efflux depended on the K+ and Na+ content, and on the history of the cells. Efflux was higher the higher the Na+ and K+ contents, and, in low-K+ cells, the efflux was also higher in cells grown in the presence of Na+ than when Na+ was given to cells grown in the absence of Na+ . Addition of K+ to cells in steady state with external Na+ resulted in a net Na+ -loss. In cells grown without Na+ this loss was a consequence of the inhibition of Na+ influx. In Na+ -grown cells, addition of K+ inhibited Na+ influx and increased Na+ efflux. 相似文献
14.
Analyses of chlorophyll fluorescence were undertaken to investigate the alterations in photosystem II (PSII) function during senescence of wheat ( Triticum aestivum L. cv. Shannong 229) leaves. Senescence resulted in a decrease in the apparent quantum yield of photosynthesis and the maximal CO2 assimilation capacity. Analyses of fluorescence quenching under steady‐state photosynthesis showed that senescence also resulted in a significant decrease in the efficiency of excitation energy capture by open PSII reaction centers (F'v /F'm ) but only a slight decrease in the maximum efficiency of PSII photochemistry (F'v /F'm ). At the same time, a significant increase in non‐photochemical quenching (qN ) and a considerable decrease in photochemical quenching (qP ) were observed in senescing leaves. Rapid fluorescence induction kinetics indicated a decrease in the rate of QA reduction and an increase in the proportion of QB ‐non‐reducing PSII reaction during senescence. The decrease in both F'v /F'm and qP explained the decrease in the actual quantum yield of PSII electron transport ((φPSII ). We suggest that the modifications in PSII function, which led to the down‐regulation of photosynthetic electron transport, would be in concert with the lower demand for ATP and NADPH in the Calvin cycle which is often inhibited in senescing leaves. 相似文献
15.
Abstract. Presence of 2.4-diaminobutyric acid (A2 bu), a neurotoxin, in tissues of flatpea ( Lathyrus sylvestris L.) necessitates a thorough understanding of the regulation of this nonprotein amino acid before the species can be recommended to livestock producers for forage applications. To determine how different concentrations and ratios of NO3 and NH+ 4 in growth media influence the levels of A2 bu and other free amino acids in the 'Lathco'flatpea cultivar, plants were grown hydroponically in controlled environments. The concentration of A2 bu was highest in tissues when the NO3 to NH+ 4 ratio in the nutrient solution was low. Responses of amides and other nonprotein amino acids, especially in the roots, followed a similar trend. Free protein amino acids in leaves and stems were generally unaffected by changes in NO3 to NH+ 4 ratios. In roots, protein amino acids increased as the NO3 to NH+ 4 ratio in the growth medium increased. Ammonium inhibited shoot and root growth; NO3 alleviated the toxic effects of NH+ 4 . Soluble protein concentrations were higher in the shoots of NO3 -fed plants and in the roots of plants supplied with NH+ 4 . These results suggest that accumulation of A2 bu and other nonprotein amino acids, as well as asparagine and glutamine, plays a role in detoxification of NH+ 4 and storage of N. 相似文献
16.
Abstract A reaction diffusion model was used to simulate the mineralization processes in an Arctic sediment. The simulation and the actual sediment were compared in relation to profiles of O2 , NO3 and NH4 + . The site of particulate organic matter (POM) degradation was the single most important factor in fitting the simulation profiles to those of the sediment. It was deduced that most POM degradation occurred close to the sediment surface. When a reasonably good simulation had been obtained, the sensitivity of the model to changes in other parameters was investigated. Increases in POM degradation in the upper sediment resulted in increases in concentration of NH4 + and NO3 − , but further increases in POM degradation created anoxic conditions below 3 mm, resulting in decreases in NO3 − concentrations. The model was relatively intensive to changes in POM degradation in the lower sediment layers; increases led to more anoxic conditions and to less NO3 − . Increases in the C/N ratio of the POM in the lower sediment layers had little effect; increases in C/N in the upper layers led to a decrease in NH4 + and NO3 − . The model was sensitive to changes in the first order rate constant for nitrification, but not for denitrification. Decreases in the K m for O2 of the nitrifying bacteria had no effect on the profiles. 相似文献
17.
Increases in cytosolic free Ca2+ ([Ca2+ ]cyt ) are common to many stress-activated signalling pathways, including the response to saline environments. We have investigated the nature of NaCl-induced [Ca2+ ]cyt signals in whole Arabidopsis thaliana seedlings using aequorin. We found that NaCl-induced increases in [Ca2+ ]cyt are heterogeneous and mainly restricted to the root. Both the concentration of NaCl and the composition of the solution bathing the root have profound effects on the magnitude and dynamics of NaCl-induced increases in [Ca2+ ]cyt . Alteration of external K+ concentration caused changes in the temporal and spatial pattern of [Ca2+ ]cyt increase, providing evidence for Na+ -induced Ca2+ influx across the plasma membrane. The effects of various pharmacological agents on NaCl-induced increases in [Ca2+ ]cyt indicate that NaCl may induce influx of Ca2+ through both plasma membrane and intracellular Ca2+ -permeable channels. Analysis of spatiotemporal [Ca2+ ]cyt dynamics using photon-counting imaging revealed additional levels of complexity in the [Ca2+ ]cyt signal that may reflect the oscillatory nature of NaCl-induced changes in single cells. 相似文献
18.
CO2 assimilation, respiration and chlorophyll fluorescence in peach leaves infected by Taphrina deformans 总被引:1,自引:0,他引:1
Vittorio Raggi 《Physiologia plantarum》1995,93(3):540-544
Photosynthesis, respiration and chlorophyll fluorescence parameters were determined in peach ( Prunus persica L. cv. Dixired) leaves naturally infected by Taphrina deformans (Berk.) Tul. and in healthy leaves (controls), in two successive springs. A drastic decrease in net photosynthesis and an evident increase in respiration in curled leaves were noted. The instantaneous PSII fluorescence yield, with no (F0 ) and with (F0 ) quenching component, and steady state fluorescence yield (under actinic light, Fs ) were essentially unchanged. Maximal fluorescence in dark-adapted (Fm ) and illuminated (F'm ) leaves and the corresponding variable fluorescence (Fv and Fv ) clearly decreased. The indicators of PSII quantum yield (Fv /Fm ) in dark-adapted leaves, and the potential PSII excitation capture efficiency (F'v /F'm ) and the quantum yield of PSII (qp [F'v /F'm ]) in the light were also significantly lower in curled leaves. Decreasing tendencies were also noted for the PSII photochemical yield (photochemical quenching, qp ) and in the energy status of the chloroplast (non-photochemical quenching, qN , and Stern-Vollmer value, NPQ) although the differences were not always significant. In curled leaves the main alteration documented is the imbalance between the drastic inhibition of CO2 fixation and the moderate decrease in photochemical reactions (i.e. Fv /Fm and ΔF/F'm ), indicating changes in the energy flux. 相似文献
19.
Andrés P. Sanz Conrado Moreno-Vivián José M. Maldonado Agustín González-Fontes 《Physiologia plantarum》1995,95(1):39-44
The effect of the nitrogen source on carbohydrate and protein contents and on several enzymatic activities involved in the carbon and nitrogen metabolism was studied in Anabaena variabilis ATCC 29413 cells grown under a constant supply of either N, NO− 3 or NH+ 4 at different concentrations. An enhancement of protein content accompanied by a parallel decrease of carbohydrates was observed with increasing NO− 3 or NH+ 4 concentrations in the medium. In cultures containing 0.1 m M NO− 3 or 0.1 m M NH+ 4 nitrogenase (EC 1.18.6.1) activity was 74 and 66%, respectively, of that found in N2 -grown cells. This activity was still present with 1 m M NO− 3 or 1 m M NH+ 4 in the medium and even with 10 m M NO− 3 , but it was completely inhibited by 5 m M NH+ 4 . Ferredoxin-nitrate reductase (EC 1.7.7.2) activity was detected only in NO− 3 grown cells and simultaneously with nitrogenase activity. Increasing concentrations of combined nitrogen in the medium, especially NH+ 4 , promoted a concomitant decline of glutamine synthetase (EC 6.3.1.2), NADP+ -isocitrate dehydrogenase (EC 1.1.1.42), and NAD+ -malate dehydrogenase (EC 1.1.1.37) activities, suggesting that these enzymes play an important role in the regulation of carbon-nitrogen metabolism in cyanobacteria. 相似文献
20.
The hydrogen peroxide (H2 O2 ) stress response in Enterococcus faecalis ATCC19433 was investigated. A 2·4 mmol l−1 H2 O2 pretreatment conferred protection against a lethal concentration (45 mmol l−1 ) of this agent. The relatively high concentrations of H2 O2 used for adaptation and challenge treatments in Ent. faecalis emphasised the strong resistance towards oxidative stress in this species. Various stresses (NaCl, heat, ethanol, acidity and alkalinity) induced weak or strong H2 O2 cross-protection. This paper describes the involvement of protein synthesis in the active response to lethal dose of H2 O2 , in addition to the impressive enhancement of synthesis of five H2 O2 stress proteins. Combined results suggest that these proteins might play an important role in the H2 O2 tolerance response. 相似文献