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71.
T. G. Nolen P. M. Johnson C. E. Kicklighter T. Capo 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(2):239-254
1. | Aplysia californica incorporates toxins and pigments from its red seaweed diet into its body and ink, purportedly as a defense against predation. We tested ink's potential defensive function by assessing the survival of green seaweed-fed (red algal toxin deprived) snails in encounters with a natural predator, the sea anemone Anthopleura xanthogrammica. |
2. | Red seaweed-fed Aplysia secreted copious amounts of ink when ensnared in anemone tentacles. A similar amount of ink applied to inkless (green-fed) snails as they were engulfed by an anemone enhanced their survival [71% survived (ink) vs 7% (seawater control)]. Ink caused anemones to reject whitefish (a familiar food) [50% rejected (ink) vs 10% (seawater control)], triggering gastrovascular eversions, which ejected ink as well as prey from their digestive cavities. Snails with only a passive chemical defense (algal toxins, no ink) escaped less often than snails with only an active chemical defense (ink, no red algal toxins) (20% survived vs 71%) and about as often as red algal toxin deprived snails (20% vs 12%). Snails avoided ink by chemical orientation, thus avoiding potential sites of ongoing predation. |
3. | The survival value of ink and the snail's aversion to it supports ink's proposed anti-predator function. |
72.
Summary This field study was undertaken to determine the effect of inoculation withGlomus mosseae on N2 fixation and P uptake by soybean. The inoculation withGlomus mosseae was achieved using a new type of inoculant, alginate-entrapped (AE) endomycorrhizal fungus. N2 fixation was assessed using the A value method. In P-fertilized plots, inoculation with AEGlomus mosseae increased the harvest index based on dry weight (+20%) and N content of seeds (+17%), the A value (+31%) and %N derived from fixation (+75%). Inoculation with AEGlomus mosseae decreased the coefficient of variation for the A value and for the dry weights of the different plant parts. 相似文献
73.
四种中草药对大鼠半乳糖性白内障氧化还原物质及糖类含量的影响 总被引:1,自引:0,他引:1
对正常和半乳糖性白内障及给中草药的大鼠晶状体中某些吡啶核苷酸成分、糖类、非蛋白质巯基的含量进行了比较。结果表明,在白内障晶状体中,NADPH及非蛋白质巯基的含量明显低于正常晶状体的,而NADP、半乳糖及半乳糖醇的含量明显高于正常晶状体的;当注射半乳糖的同时分别用黄岑、石斛、菟丝子及玉蝴蝶四种中草药水煎剂灌胃,上述变化为基本恢复至正常晶状体的水平。表明四种中草药对晶状体中的异常生化变化具有阻止及纠正作用。 相似文献
74.
75.
H. Mercier C. C. J. Vieira R. C. L. Figueiredo-Ribeiro 《Plant Cell, Tissue and Organ Culture》1992,28(3):249-254
Leaf and stem segments of Gomphrena officinalis originated from aseptically grown seedlings were used to initiate cultures. Callus production was obtained on gelled Murashige & Skoog medium supplemented with 6-benzylaminopurine alone (1.0, 5.0 or 10.0 mgl-1) or combined with -naphthalene acetic acid (0.1, 0.5 and 1.0 mgl-1) after 10 to 15 days of culture, and can be transferred to fresh medium every 30 days. The combinations of 5.0 or 10.0 mgl-1 of 6-benzylaminopurine with 0.1 mgl-1 of -naphthalene acetic acid were found to be the best for shoot regeneration. Adventitious shoot formation occurred after 50 to 60 days of culture in leaf and internode stem explants. Nodal segments developed actively growing lateral buds after 30 days of culture. Gelled Murashige & Skoog medium containing 10 mgl-1 of indole-3-butyric acid was considered optimal for the rooting of shoots. Rooted plants transferred to potting soil could be successfully established.Abbreviations BA
6-benzylaminopurine
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- MS
Murashige & Skoog
- NAA
-naphthalene acetic acid 相似文献
76.
Summary The chemical equilibrium and E value for Zn was calculated in 9 soils of Haryana (India) which represented mainly entisol
and inceptisols. The rate of isotopic exchange between65Zn and native soil Zn was quite rapid and radioactivity reduced to about 0.2 per cent of initial activity after 3 days but
total Zn concentration in soil solution did not decrease. In 5 out of 9 soils equilibrium was established in 2 to 3 days.
In typic ustochrepts having high clay content (3,4) equilibrium was attained in two days. In typic udipsamments (2), typic
camborthids (8) and aquic vertic ustichrepts (9) it took 3 days to set equilibrium. Typic ustochrepts (5) took 5 days for
equilibrium whereas typic ustipssaments (6) and typic camborthids of high O.C. did not attain equilibrium even in 7 days.
This indicated that the chemistry and availability of Zn in soil would depend on soil types.
When ZnE was estimated by applying activity after equilibrium with carrier Zn and by applying activity with carrier Zn before equilibrium
was set, there was no agreement in ZnE in two methods. Increasing ZnE with increasing Zn dose was observed by both methods only in alkaline typic ustochrept (4). In some soils higher E values
than added amounts were observed, whereas, in soil 8 negative E values were obtained. The E values become erratic and are
over estimated where complex reactions take place due to high pH, high O.C. and high complex forming elements. 相似文献
77.
Craig S. Tucker 《Hydrobiologia》1981,85(1):73-76
Eichhornia crassipes (Mart.) Solms, Pistia stratiotes (L.), and Lemna minor (L.) were cultured at four different densities each and analyzed for cell-wall fraction, crude protein, total available carbohydrate and ash. Cell-wall fraction increased and crude protein content decreased as density increased in Eichhornia and Pistia cultures. The cell-wall and crude protein content of Lemna did not change with increasing culture density. Differences in the trends of cell-wall and crude protein content of the three plants at increasing culture densities appear to be related to differences in growth form. There was no difference in the total available carbohydrate or ash content of the three species at different culture densities. 相似文献
78.
《Saudi Journal of Biological Sciences》2018,25(2):320-325
Honey is a natural food item produced by honey bees. Ancient civilizations considered honey as a God gifted prestigious product. Therefore, a huge literature is available regarding honey importance in almost all religions. Physically, honey is a viscous and jelly material having no specific color. Chemically, honey is a complex blend of many organic and inorganic compounds such as sugars, proteins, organic acids, pigments, minerals, and many other elements. Honey use as a therapeutic agent is as old as human civilization itself. Prior to the appearance of present day drugs, honey was conventionally used for treating many diseases. At this instant, the modern research has proven the medicinal importance of honey. It has broad spectrum anti-biotic, anti-viral and anti-fungal activities. Honey prevents and kills microbes through different mechanism such as elevated pH and enzyme activities. Till now, no synthetic compound that works as anti-bacterial, anti-viral and anti-fungal drugs has been reported in honey yet it works against bacteria, viruses and fungi while no anti-protozoal activity has been reported. Potent anti-oxidant, anti-inflammatory and anti-cancerous activities of honey have been reported. Honey is not only significant as anti-inflammatory drug that relieve inflammation but also protect liver by degenerative effects of synthetic anti-inflammatory drugs. This article reviews physico-chemical properties, traditional use of honey as medicine and mechanism of action of honey in the light of modern scientific medicinal knowledge. 相似文献
79.
80.
《Bioscience, biotechnology, and biochemistry》2013,77(10):1958-1959
A sandwich chemiluminescence enzyme immunoassay for measuring the level of VEGF /VPF in serum was constructed. The detectability of the assay is very low (1.0pg/ml) and the measurable range of the assay was very wide (1–1000 pg/ml). The assay showed that the average level of VEGF /VPF in human sera from healthy blood donors was approximately 19 pg/ml. 相似文献