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1.
The effect of long-term exposure of vibration and feeding rabbits with liquorice (Glycyrrhiza glabra L) on peripheral blood indicators was studied. It was found that biological active substances of licorice accelerate metabolism processes of the marrow stem cells, enlarge organism compensatory abilities, in that way providing organism resistance to vibration.  相似文献   

2.
Experimental infections of 1-mm high snails using three populations of Lymnaea (L. glabra, L. ovata and L. truncatula) and a cattle strain of Fasciola hepatica miracidia were carried out under laboratory conditions to determine if the snail species had an effect on the number of free rediae, their growth, and cercarial productivity in relation to each redial category (R1a, R1b, R2a, or R2b/R3a). The total number of rediae ranged from 6.4 to 7.5 per snail. The mean body length of rediae varied from 1-1.2 mm (R1a) to 0.3-0.4 mm (R2b/R3a). The width of the intrapharyngeal lumen also varied from 26.0-38.8 microm to 3.0-4.2 microm, respectively. The redial category had a significant effect on both measurements, whereas snail species only had a significant influence on body length. The mean number of cercariae produced by all living rediae at day 49 post-exposure ranged from 63.0 in L. glabra to 87.2 in L. truncatula. In L. ovata and L. truncatula, 55.8% and 58.6% of cercariae, respectively, were produced by R2a rediae, whereas 53.9% of cercariae in L. glabra were formed by the R1b rediae. When young snails were infected with F. hepatica, the species of snail had an effect on the number of living rediae, their length and their cercarial productivity.  相似文献   

3.
In experiments of 1, 15 and 30-day chicks, studies have been made of adaptational changes in the activity of maltase and saccharase from different parts of the small intestine during feeding by sucrose. It was found that the increase in the activity of the mentioned enzymes during sucrose utilization takes place only in 30-day chicks. At earlier stages of ontogenesis, adaptational changes in the activity of disaccharidases are directed to the enhancement of the decrease in the activity of maltase and saccharase in the small intestine, this decrease being observed at these stages in control chicks.  相似文献   

4.
药用植物草珊瑚RAPD扩增条件优化   总被引:2,自引:1,他引:2  
张志勇  何平 《广西植物》2009,29(4):455-458
采用CTAB-DNA提取方法,从草珊瑚植物的嫩叶中提取总DNA。以此DNA为模板,优化了草珊瑚RAPD-PCR的反应条件。结果表明,PCR扩增体系最适宜的条件为:反应体积25μL,内含2.5mmol/L Mg2+、1.0UDNA聚合酶、0.4μmol/L引物、60ng模板DNA和0.16mmol/L dNTP。扩增程序为:94℃预变性2min;94℃变性30s,37℃复性30s,72℃延伸80s,40个循环;72℃延伸10min;4℃保存10min。  相似文献   

5.
In organic cucumber production infection with downy mildew (Pseudoperonospora cubensis) is a major problem. Plant extracts from Glycyrrhiza glabra L. (licorice), a plant belonging to the family Fabaceae, and Salvia officinalis (sage) as well as cultures of the bacterium Aneurinibacillus migulanus were investigated for efficacy of disease control under commercial growing conditions. Contrary to bioassays, where sage extract and the microorganism showed highest activity, in the trials of 2008 G. glabra extract was more effective than sage extract or A. migulanus against P. cubensis. Parameters such as concentrations of the preparations or application intervals could have been the reason for this. In the following year's trial (2009) the concentration of these agents was therefore increased somewhat and plants were either treated in seven day application intervals or in ten day application intervals. In the semi-commercial trials of 2009 all alternative biological agents showed good efficacies up to around 80% against infection with downy mildew. The application interval seemed to have a marginal effect only. Again, the licorice extract tended to be the best agent.  相似文献   

6.
The cometabolic transformation of 2,4,6-trinitrotoluene (TNT) by an immobilized Phanerochaete chrysosporium culture was investigated under different TNT and/or glycerol feeding conditions in a 5-L reactor. In the fed-batch feeding mode, as a result of four spiking events at an average feeding rate of 20 mg TNT L(-1) d(-1) and 250 mg glycerol L(-1) d(-1), the initial TNT transformation rate and the glycerol uptake rate of the 7-day-old immobilized cell culture were 2.41 mg L(-1) h(-1) and 16.6 mg L(-1) h(-1), respectively. Thereafter, the TNT fed into the reactor depicted a negative effect on the cell physiology of P. chrysosporium, i.e., both rates decreased constantly. At 32 mg TNT L(-1) d(-1) feeding rate, also in the presence of glycerol (200 mg L(-1) d(-1)), this effect on the fungal cell metabolism was even more significant. When TNT was fed alone at 3.7 mg L(-1) d(-1), it showed an initial 0.75 mg L(-1) h(-1) rate of TNT transformation, i.e., one-third the initial level observed in the presence of glycerol. In contrast, in the continuous feeding mode (dilution rate, D = 0.11 d(-1)), at 5.5 mg TNT L(-1) d(-1) and 220 mg glycerol L(-1) d(-1), the immobilized cell culture exhibited a constant TNT transformation rate for cultivation periods of 50 and 61 days, under uncontrolled and controlled pH conditions, respectively. Thereafter, during the latter experiment, 100% TNT biotransformation was achieved at 1,100 mg L(-1) d(-1) glycerol feeding rate. Immobilized cells (115-day-old), sampled from a continuous TNT feeding experiment, mineralized [(14)C]-TNT to a level of 15.3% following a 41-day incubation period in a microcosm.  相似文献   

7.
The levels of cyanogenic glucosides (linamarin and lotaustralin) and the activity of linamarase were studied in 5-day old seedlings of oil flax (Linum usitatissimum L., cv. LCSD 200) under different environmental conditions. White light enhanced the cyanoglucosides content, and this effect depended on its intensity and the time of exposure. The level of cyanoglucosides rose with temperature, and it reached the highest level at the highest temperature (30 °C). Linamarase (EC. 3.2.1.21) activity was the highest at 20°C, especially in light-grown seedlings. Lower enzyme activity at the extreme temperature (15 and 30 °C) was observed. Water stress (low water potential, ω=−0.34 MPa) reduced by more than twice the cyanoglucoside level and linamarase activity. The possible protective, or/and regulatory roles of cyanogenic glucosides was discussed.  相似文献   

8.
In May 2004, 400 tree seedlings of seven different species found on tree islands in the Florida Everglades were planted at different elevations along five transects on eight newly constructed tree islands, four with and four without limestone cores. Seedlings suffered between 40 and 85% mortality during the first 120 days, the period with the lowest water levels. Ilex cassine L., Salix caroliniana Michx., Chrysobalanus icaco L., and Annona glabra had the highest number of surviving seedlings, whereas Magnolia virginiana L., Myrica cerifera L., and Acer rubrum L. had the fewest. During the remainder of the study, water levels were mostly higher and sometimes covered the entire islands for months at a time. After 220 days, nearly all seedlings of M. virginiana and My. cerifera had died. At the end of the study, seedlings of I. cassine and A. glabra had the highest survivorship rates. Seedling biomass of C. icaco and I. cassine was greatest at the highest elevations, whereas seedlings of A. glabra had similar biomass at all elevations. Seedling survivorship was not statistically different between islands with and without limestone cores; however, when seedlings of all species were combined, island core type was significantly different for aboveground biomass, seedling height, and canopy width. Because of the higher survivorship under both low and high water conditions, A. glabra , I. cassine , and S. caroliniana are the most suitable species for establishing tree species on restored tree islands in the Everglades.  相似文献   

9.
Phlebotomus papatasi (Scopoli) is susceptible to infection with Leishmania major Yakimov & Schokov and resistant to L. donovani Laveran & Mesnil. The possibility that susceptibility depends on midgut levels of trypsin and chymotrypsin-like (esterolytic) enzymes was investigated. Infection with L. major reduced the trypsin-like activity to 93.5% and 86% of the control value at 20 and 30 h post feeding and increased it to 106% at 52 h. Infection with L. donovani reduced trypsin-like activity to 64% and 73% of the control value at 30 and 52 h post feeding. The overall amount of trypsin and chymotrypsin-like enzymes in L. major infections was reduced to 50% and 34% of the control value at 20 and 30 h post feeding and increased to 184% at 52 h. Only one of the enzymes separated by gel electrophoresis was lower throughout, i.e. peak D. Overall, the midgut enzyme level with L. donovani infection was 86% of the control value at 30 h post feeding and 105% at 52 h; their relative amounts changed throughout. Soybean trypsin inhibitor enabled L. donovani to survive and multiply in P. papatasi. It is suggested that a specific component of the trypsin-like activity prevents the survival of L. donovani in P. papatasi and that modulation of this factor enables L. major to survive.  相似文献   

10.
菝葜与土茯苓黄酮类化合物的比较研究   总被引:2,自引:0,他引:2  
对菝葜和土茯苓根茎中黄酮类化合物进行了定量测定和定性分析.结果表明:在菝葜和土茯苓根茎中均含有黄酮,黄酮醇,二氢黄酮,二氢黄酮醇等多种黄酮类化合物.以芦丁为标准品,用分光光度法测知菝葜和土茯苓根茎中总黄酮含量分别为3.36%和2.22%.  相似文献   

11.
Low-frequency vibration, irrespective of its duration (20 Hz, A = 0.4 mm), is shown to increase GABA level, glutamatedecarboxylase enzyme activity (EC 4.1.1.15) in the large hemispheres, cerebellum, brain stem of adult male rats (12 months). Meanwhile GABA aminotransferase activity (EC 2.6.1.19) remains, mainly, unchanged. The observed shifts are more clear under 30 min vibration than under 7h and 30 day effects. Glutaminic and aspartic acids content increases under 30 min and decreases under 7h and 30 day vibration in the given brain structures.  相似文献   

12.
基质温度对三角梅插穗生根及其叶片光合作用的影响   总被引:2,自引:0,他引:2  
探讨了智能调控下18、20、25、30、33℃的5个基质温度处理对三角梅叶片光合作用及插穗生根的影响.结果表明:随着基质温度上升,三角梅插穗叶片净光合速率增加,18、20℃处理的净光合速率较低,两处理间未见显著性差异,但均显著地低于处理间未见明显差异的25、30、33℃处理.随着基质温度上升,叶片蒸腾速率、气孔导度及胞...  相似文献   

13.
Effects of nitrite inhibition on anaerobic ammonium oxidation   总被引:6,自引:0,他引:6  
In order to assess the stability of nitrogen removal systems utilizing anaerobic ammonium oxidation (anammox), it is necessary to study the toxic effects of nitrite on these biochemical reactions. In this study, the effects of nitrite on anammox bacteria entrapped in gel carriers were investigated using batch and continuous feeding tests. The results showed that the nitrite concentration in a reactor must be less than 274-mg N/L in order to prevent a decrease in the anammox activity, which occurred when the gel carriers were soaked in nitrite solutions with concentrations greater than 274-mg N/L in a batch test. In a continuous feeding test, nitrite inhibition was not observed at low concentrations of nitrite. However, the anammox activity decreased to 10% when the nitrite concentration increased to 750-mg N/L over a 7-day period in the reactor. In addition, it was shown that the effects of nitrogen on the anammox reaction were reversible because the anammox activity completely recovered within 3 days when the influent nitrite concentration was decreased to less than 274-mg N/L.  相似文献   

14.
Abstract

The possible endogenous circadian rhythm in the feeding activity of rainbow trout (Oncorhynchus mykiss) was investigated using individual fish previously trained for self‐feeding. Under LD 12:12 conditions, the fish showed a diurnal behaviour, in many cases with a feeding rhythm with two main peaks of food demand at dawn and dusk, with an 8h interval of low feeding activity, and the actograms showed an expected 24 h rhythm. Fish kept under constant conditions (L : L, 15°±0.5°C), showed free‐running feeding activity for about 12 days. Food demands were concentrated at dawn, with a periodogram of 25.3 hour, under continuous environmental conditions. Results showed evidence for the endogenous origin of the circadian rhythm of feeding in this species.  相似文献   

15.
以盆栽小叶紫三角梅(Bougainvillea glabra ‘Sanderiana’ )为供试品种,在自然生长条件下,采用正交试验设计,研究不同浓度多效唑、康朴、阿迈速对其花期调控的影响。结果表明,多效唑对小叶紫三角梅的枝条生长影响最大,表现为抑制枝条节间伸长生长,促进花芽数量增加;阿迈速对三角梅花期调控影响效应最大,表现为促进开花、提高品质;3种药剂对三角梅的酶活性影响表现各异。小叶紫三角梅的药剂花期调控以定时花期效果为主,最优药剂组合为多效唑1.2 g·L-1+康朴1.5 g·L-1+阿迈速0.5 mL·L-1,还需配合适当的植株水分管理。  相似文献   

16.
Previous studies demonstrated that third-stage, developmentally arrested larvae of the canine hookworm Ancylostoma caninum resume feeding in vitro in response to canine serum and hostlike temperature. Experiments to determine the identity of the serum stimulus are described. Serum from several nonhost species stimulated feeding, but to levels lower than canine serum. Heating the serum to 57 C had no effect on its stimulatory ability. Dialysis reduced serum stimulatory activity by 50%, and ultrafiltration through 10- and 30-kDa molecular weight cut-off membranes decreased activity in both the filtrates and retentates similarly. Recombination of the filtrates and retentates restored activity to whole serum control levels. Commercial canine and bovine albumin stimulated feeding to serum control levels at 10 and 50 mg/ml, respectively. These results suggest that albumin and an unidentified low molecular weight compound(s) are capable of inducing in vitro feeding by A. caninum L3.  相似文献   

17.
The intensity of lipid peroxidation and activity of antioxidant system enzymes in the blood plasma, brain and cardial muscle of laboratory rats under 40 days of isolation and violation of diurnal cycle was studied. The obtained data show that on the background of concentration changes in NO changes also take place in the intensity of lipid peroxidation process, indicated by changes in the concentration of TBA-active products and diene conjugates. The changes taking place in the activity of superoxidedismutase, catalase, succinatdehydrogenase, creatine kinase and aldolase under stress were studied. The resulting data show that isolation of animals and violation of diurnal cycle are the factors causing a significant reduction in the energy metabolism in the brain and heart tissue cells and resulting in oxidative stress that, in its turn, may become the reason for development of toxic radicals. Furthermore, prolonged stress may result in irreversible processes that are considered to be the reasons for significant pathologies of the cardiovascular system.  相似文献   

18.
Random amplified polymorphic DNA (RAPD) profiling revealed geneticdiversity among three populations ofLicuala glabra var. glabra,an understorey palm growing in the dipterocarp forests of Terengganu,Malaysia. The Bukit Bauk population had individuals withoutaerial stems. The Bukit Besi individuals had stem heights to30 cm, while those of the Rasau Kerteh population had stemsup to 4 m in height. Southern blot analysis confirmed that anapparent monomorphic band generated by the primer OPU-17 amongthe three different populations corresponds to the same locus.Six primers were used to generate 87 RAPD bands that formed2-state character raw data for estimating genetic distancesusing the simple matching coefficient of similarity. The phenogramgenerated by UPGMA of the RAPD data grouped the individualsfrom the three populations under three clusters. This was inagreement with the morphological grouping. The infraspecificL. glabra var.selangorensis Becc. was grouped closer to theL. glabra var. glabra individuals than to the outgroupL. scortechiniiBecc. Principal component analysis supported the observationfrom the phenogram. The results show discrete genetic structuringin the populations studied and provide useful information forfuture conservation measures. Copyright 1999 Annals of BotanyCompany Licuala glabra Griff. var. glabra, RAPD, palm, AMOVA, population, genetic diversity, conservation.  相似文献   

19.
The present study investigated the immunomodulatory activity of Ergosan, an algal extract containing alginic acid, and Macrogard, a yeast extract containing beta-glucans, on innate and specific immunity in sea bass (Dicentrarchus labrax). Four cycles of experimental feeding using normal fish feed formulation (control group) supplemented with Ergosan (0.5%) or Macrogard (0.1%) were performed at 60-day intervals (15 days of treatment+45 days of suspension). Serum complement, lysozyme, total proteins and heat shock protein (HSP) concentrations were measured at 15, 30 and 45 days from the end of the first 15-day feeding cycle (short term) and 45 days after the end of each feeding cycle over a 35-week period (long term). The percentage of B- and T-lymphocytes in peripheral blood leucocytes and gut were measured over long-term trial. Significant elevation (P < 0.05) in serum complement activity occurred in sea bass fed with alginic acid and glucans, at 15 days from the end of first cycle of treatment. Significant elevation (P < 0.05) in serum lysozyme, gill and liver HSP concentration were observed in the same experimental groups at 30 days from the end of treatment, whereas a significant increase (P < 0.05) of complement activity was only observed in fish that received an Ergosan diet. At 45 days from the end of treatment, complement, lysozyme and HSP concentration did not differ among groups. Over the long-term period, no significant differences were observed in innate and specific immune parameters, survival, growth performances and conversion index in treated and control fish. A dramatic decrease of both innate and acquired immune parameters was observed during the winter season in all groups, followed by a partial recovery when water temperature increased. Reduction in complement and lysozyme activities was significatively correlated (p < 0.01) to water temperature variation. The results suggested the potential of alginic acid and beta-glucans to activate some innate immune responses in sea bass, and particularly under conditions of immunodepression related to environmental stress.  相似文献   

20.
Earthworm activity is known to increase emissions of nitrous oxide (N(2)O) from arable soils. Earthworm gut, casts, and burrows have exhibited higher denitrification activities than the bulk soil, implicating priming of denitrifying organisms as a possible mechanism for this effect. Furthermore, the earthworm feeding strategy may drive N(2)O emissions, as it determines access to fresh organic matter for denitrification. Here, we determined whether interactions between earthworm feeding strategy and the soil denitrifier community can predict N(2)O emissions from the soil. We set up a 90-day mesocosm experiment in which (15)N-labeled maize (Zea mays L.) was either mixed in or applied on top of the soil in the presence or absence of the epigeic earthworm Lumbricus rubellus and/or the endogeic earthworm Aporrectodea caliginosa. We measured N(2)O fluxes and tested the bulk soil for denitrification enzyme activity and the abundance of 16S rRNA and denitrifier genes nirS and nosZ through real-time quantitative PCR. Compared to the control, L. rubellus increased denitrification enzyme activity and N(2)O emissions on days 21 and 90 (day 21, P = 0.034 and P = 0.002, respectively; day 90, P = 0.001 and P = 0.007, respectively), as well as cumulative N(2)O emissions (76%; P = 0.014). A. caliginosa activity led to a transient increase of N(2)O emissions on days 8 to 18 of the experiment. Abundance of nosZ was significantly increased (100%) on day 90 in the treatment mixture containing L. rubellus alone. We conclude that L. rubellus increased cumulative N(2)O emissions by affecting denitrifier community activity via incorporation of fresh residue into the soil and supplying a steady, labile carbon source.  相似文献   

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