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271.
The objective of this study was to determine the ratio and amount of Fe II and Fe III iron in different parts of 20 and 40 day old bean plants grown in pots under normal and HCO-treatment. The Fe II and Fe III iron determination was carried out by a modification of a method described by Vogel (1969). The Fe II and Fe III concentrations in the plant varied according to its age, the plant part, the order of leaves and HCO-treatment. At the second sampling date, the lower total iron content in the lower leaf particularly under the HCO-treatment suggests that the supply of iron from the roots was restricted. The iron content of the different leaves was almost evenly divided into Fe II and Fe III at the first date. At the second date, most of the iron in the bud leaf was present as Fe II. Under HCO-treatment the Fe II content of the bud leaf and the flower was similar as in the corresponding parts of the normal green plants whereas the Fe III content was considerably lowered in these plant parts as result of the HCO-treatment. The results indicate a substantial retranslocation of iron from older to younger leaves and a higher Fe II/Fe III ratio in flowers and bud leaves particularly under HCO-induced chlorosis.  相似文献   
272.
Hepatic progenitor cells are periportally resident cells capable of differentiating into mature hepatocytes or cholangiocytes to ensure hepatic regeneration. This reaction is termed a ductular reaction. In the present study, regenerative response of the feline liver to different hepatic diseases was investigated immunohistochemically. Regeneration of the liver through hepatocellular replication and proliferation of progenitor cell compartment were comparatively evaluated. Histological and immunohistochemical stainings were conducted on feline liver samples (n=40) representing various hepatobiliary diseases. Cytokeratin (CK) 7, CK19, Proliferating cell nuclear antigen (PCNA), Ki67, and Human hepatocyte marker 1 (Hep Par-1) were used. The presence of progenitor cells within feline livers was proved, both as passive cells in normal liver and as active cells (ductular reaction) in hepatic lesions. CK7 was found to be a suitable antibody for immunohistochemically detecting feline progenitor cells. In acute events, regeneration was predominantly shaped by the division of hepatocytes. In chronic events and severe acute events, hepatocytes lost their ability to divide and regeneration mainly occurred through progenitor cells. Location of the ductular reaction varied between different hepatic diseases. Parenchymal ductular reaction was detected in fulminant hepatitis, chronic hepatitis, hepatocellular lipidosis and metastatic lymphoma, whereas septal ductular reaction was detected in chronic hepatitis and metastatic lymphoma. Ductular reaction exhibited positive staining for Hep Par-1 in chronic and severe acute events. This study indicates the major role played by hepatic progenitor cells in regeneration of the feline liver. Moreover, it shows how the activation pattern of ductular reaction varies according to the hepatobiliary disease type.  相似文献   
273.
ABSTRACT

Laboratory experiments were conducted to investigate how incorporation of the winter grasses foxtail (Alopecurus aequalis) and milk vetch (Astragalus sinicus) into flooded paddy soil affects the germination of summer weeds and soil inorganic nitrogen (N) levels. Polyethylene terephthalate (PET) vessels (10.0 × 8.0 × 15.0 cm) were filled with 0.7 kg air-dried soil that had been collected from organic paddy fields located in Tochigi, Japan. Foxtail and milk vetch were then independently incorporated into the soil at rates of 0% (untreated control), 0.25%, 0.5%, 1%, and 1.5%, with four repetitions per treatment. The PET vessels were placed in a growth chamber (Biotron) set to day/night temperatures and humidities of 27/18°C and 70%/65%, respectively, and with an illuminance of 40,000 lx (12 h) for 28 days, and the total number of weeds and changes in the electrical conductivity (EC) of the surface water were investigated throughout this period, while changes in soil inorganic N were determined at the ends of the experiments. The incorporation of both foxtail and milk vetch significantly suppressed the germination of summer weeds by 56% and 50%, respectively, at incorporation rates of 1% and by 78% and 77%, respectively, at incorporation rates of 1.5% compared with their respective controls. There was a high and significant positive correlation between both the rate of winter grass incorporation and the degree of growth suppression and EC. Incorporation of foxtail at rates of 0.25% and 0.5% significantly increased the inorganic N contents of the sub-layer by an average of 68% compared with the control but had no significant effect in the top layer, whereas the incorporation of milk vetch at a rate of 1% significantly increased the inorganic N contents of both the top layer and sub-layer by 200% and 316%, respectively, compared with the control. Furthermore, the effect of milk vetch on inorganic N significantly increased with an increase in the rate of incorporation. These findings demonstrate that incorporation of the winter grasses foxtail and milk vetch into flooded organic paddy soil can suppress weed growth and act as a source of inorganic N.  相似文献   
274.
Zusammenfassung Zwecks Untersuchung der Beutepräferenz und der Effizienz des räuberischen NematodenDiplogaster sp. wurden dessen Adulten mit den Larven zweier pflanzenparasitärer Nematodenarten (Pratylenchus zeae undMeloidogyne incognita var. 3) sowie mit den Larven zweier Fliegenarten (Ceratitis capitata undMusca domestica) zusammen gehalten.Die Ergebnisse zeigen, daß dieDiplogaster-Nematoden einen großen Teil der Beutetiere fraßen, und zwar in der ReihenfolgeM. incognita, P. zeae, C. capitata undM. domestica. Die beiden phytoparasitären Nematodenarten wurden somit den Insekten-larven vorgezogen. Die Vernichtungsquoten betrugen in dieser Reinhenfolge 81,5-76-55 und 44%.
Effect of different kinds of food source on the predation efficiency ofDiplogaster sp. nematode (Rhabdita, Diplogasteridae)
The present investigation was conducted to assess the favorable prey of different vermiform larvae of certain insects (Ceratitis capitata, Musca domestica) and phyto-parasitic nematodes (Pratylenchus zeae, Meloidogyne incognita var. 3) which would exterminated by the predator nematode,Diplogaster sp.The obtained results indicate thatDiplogaster sp. exteriminated large numbers of prey ofM. incognita var. 3 andP. zeae, followed byC. capitata andM. domestica. The larvae of phytoparasitic nematodes were preferable prey toDiplogaster nematode, than that of insects. The predatious rate on the larvae ofM. incognita, P. zeae, C. capitata andM. domestica was 81.5, 76, 55, and 44%, respectively.


Mit einer Tabelle  相似文献   
275.
The studies showed that herbicides i. e. Treflan had side effects in controllingMeloidogyne javanica (38.1% reduction in nematode population) followed by Gramoxone (15.1% reduction), while Dowpon “S” and Cotoran showed lethal phytotoxic effects on the tomato plants.  相似文献   
276.
A field investigation of two faba bean cultivars (cv.), Agabat and Silaim, showed that bean yellow mosaic virus (BYMV) infection reduced (p≤0.001) yield (Kg/ha), protein content and in vitro protein digestibility (IVPD) but increased (p≤0.05) tannin content (mg/100 ml). Nitrogen fertilization with viral infection significantly reduced yield and IVPD for cv. Silaim and increased (p≤0.05) protein and tannin contents. Nitrogen fertilization alone was found to increase (p≤0.05) yield, protein and tannin contents but slightly reduced IVPD.Rhizobium inoculation with viral infection significantly decreased yield per unit area, protein content and IVPD, but increased (p≤0.05) tannin content.Rhizobium inoculation alone significantly increased (p≤0.001) yield and tannin content and slightly increased protein content but decreased IVPD. The results indicated that nitrogen fertilization or nitrogen fixation increased yield, protein and tannin contents and decreased IVPD. Viral infection had an adverse effect on yield, protein content and IVPD but had no effect on tannin content.  相似文献   
277.
1. The main aim of this work is to develop a robust method to generate a microbial mixture which can successfully degrade poultry feathers to overcome environmental problems.

2. Four different alkaliphilic microbes were isolated and shown to degrade poultry feathers.

3. Two of the isolates were phylogenetically identified as Lysinibacillus and the others were identified as Nocardiopsis and Micrococcus.

4. The best microbial co-culture for white and black feather degradation was optimised for pH, temperature and relative population of the isolates to achieve almost 96% of degradation compared with a maximum of 31% when applying each isolate individually.

5. The maximum activity of keratinase was estimated to be 1.5 U/ml after 3 d for white feathers and 0.6 U/ml after 4 d for black feathers in a basal medium containing feather as the main carbon source. Additionally, non-denaturing polyacrylamide gel electrophoresis showed 4 and 3 protease activity bands for white and black feather, respectively.

6. This study provides a robust method to develop potential new mixtures of microorganisms that are able to degrade both white and black feathers by applying a Central Composite Design.  相似文献   

278.
In this study, the optimum conditions for the ammonia removal from aqueous solution by microwave-assisted air stripping have been investigated at pH 11. Ammonia solution with five different initial ammonia concentrations was prepared synthetically. The Taguchi method was applied to optimize the ammonia removal conditions. Initial ammonia concentration, air flow rate, temperature, stirring speed, microwave radiation power, and radiation time were defined as the optimization parameters. Experiments were carried out at five different levels for each operational parameter. The results of the experiments revealed that 1800 ppm of initial ammonia concentration, 7.5 L min?1 of air flow rate, 60 °C of temperature, 500 rpm of stirring speed, and 500 W of microwave radiation power for 180 min. of microwave radiation time are optimum conditions for complete ammonia removal. In addition to present experimental data, the optimum operational conditions predicted by the balanced characteristics of orthogonal array were confirmed experimentally. Finally, the effect of optimization parameters was discussed in detail.
Graphical Abstract ?
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279.
Extreme high-temperature stress (HTS) associated with climate change poses potential threats to wheat grain yield and quality. Wheat grain protein concentration...  相似文献   
280.
以西昆仑山2个海拔样点的土样为对象,利用(LB和TSA)2种培养基,基于16S rRNA基因序列的系统发育,采用纯培养法对其可培养细菌多样性进行研究。2样点中共分离到91株细菌,分为25个属,52个种。厚壁菌门(Firmicutes)占总菌数的48.75%,放线菌门(Actinobacteria)占36.25%,γ-变...  相似文献   
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