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111.
S. Rana S.K. BagD. Golder S. Mukherjee C. Pradhan B.B. Jana 《Ecological Engineering》2011,37(6):981-988
In search of low-cost eco-tech for the reclamation of municipal domestic wastewater, tomato plants (Lycopersicum esculentum) were cultivated on the floating bed of pulp-free coconut fiber over four different concentrations of wastewater (25%, 50%, 75% and 100%) and groundwater as control, in 10 L plastic bucket for two months. The study revealed that PO4-P was removed by 58.14-74.83% with maximum removal at 50% wastewater. More than 75% removal of NO3-N was observed in all treatments. Both COD and BOD were reclaimed highest at 100% wastewater by 61.38% and 72.03%, respectively. Ammonium-N concentration was subsided below the toxic level in all the treatments. The population of coliform bacteria (Escherichia coli) was reduced to 91.10-92.18% with maximum efficiency at 100% wastewater. Growth performance was observed relatively better at 100% wastewater. Crop production as the value addition of this technology was also recorded maximum at 100% wastewater. The bioaccumulation of Cd and Ni in tomato crop was far below the threshold level, but the bioaccumulation of Pb and Cr was above the safe level by 80 times and 660 times, respectively. The aquaponically reclaimed water can be reused in agriculture, aquaculture and industries. 相似文献
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114.
Professor Anne Résibois Françoise Rypens Roland Pochet 《Cell and tissue research》1988,251(3):611-620
Summary It is well known that calbindin immunoreactivity is highly concentrated in the duodenal absorptive cells of young birds. We have shown that in the adult intestine of three avian species, calbindin content is much more variable. In addition to absorptive cells, we have detected throughout the gut of both sexes of the domestic fowl and in the large intestine of the Japanese quail a second type of calbindin-positive epithelial cell which has the shape of a typical endocrine cell. These cells were particularly abundant in the large intestine, in contrast to the usual distribution of endocrine cells along the gut. Calbindin was also detected in the nervous system of the intestine. Calbindinpositive nerve fibres were rare in the duodenum and ileum, numerous in plexuses and nerve processes in both muscular layers and lamina propria of the large intestine in domestic fowl and Japanese quail. In the mallard, nerve fibres were rarely calbindin positive while definitively positive for VIP. Calbindin of the peripheral nervous system of the domestic fowl and Japanese quail comigrates with the duodenal calbindin (27000 dalton) in SDS gel electrophoresis. 相似文献
115.
Summary Substance P and calcitonin gene-related peptide were immunohistochemically identified in axons innervating the cornea and the ureter of adult rats and pigeons. The two neuropeptides were similarly distributed in both species. Capsaicin pretreatment induced depletion of the immunoreactivity; this was quantitatively and qualitatively different in rats and pigeons. Topical application of capsaicin (1%) reduced the immunoreactivity in the cornea in both species by 50%. Systemic capsaicin treatment completely depleted both peptides from the corneal innervation of rats but reduced the peptide content only by 50% in the cornea of pigeons. In the ureter of rats, capsaicin pretreatment completely depleted the peptide immunoreactivity. In pigeons the peptide depletion was only complete in the outer longitudinal muscle layer. Whereas only a few immunoreactive fibres were observed in the circular muscle layer, about 50% of the peptide remained in the inner longitudinal muscle layer. The results demonstrate that peptidergic afferents in the cornea and ureter of pigeons are sensitive to capsaicin, although birds do not show nociceptive responses to local administration of the drug. The long-term depletion of substance P and calcitonin gene-related peptide by capsaicin is discussed with regard to the possibility that functionally capsaicin receptors may exist in the axon but not at nerve endings.Part of the thesis of Gerhard Harti, to be presented to the Fachbereich Biologie, Justus-Liebig-Universität, Giessen 相似文献
116.
《Saudi Journal of Biological Sciences》2017,24(1):30-35
The present study determined the prevalence and distribution of gastrointestinal helminths in domestic chickens (Gallus gallus domesticus) between November 2012 and August 2013. One hundred and twenty domestic chickens were purchased from villages in four districts of Phayao province; Mae Chai, Dok Khamtai, Chun and Chiang Kham. Morphological differences were used to identify the helminth species, and HAT-RAPD technique was used to differentiate among closely related species. The results revealed that the total prevalence of infection was 99.2%. Cestode and nematode infections showed the highest prevalence in rainy season, while trematode infections were low and only found in hot season. The species and their prevalence were: Ascaridia galli (50.8%), Heterakis gallinarum (86.7%), Prosthogonimus macrorchis (1.7%), Echinostoma revolutum (0.8%), Raillietina echinobothrida (48.3%), Raillietina tetragona (57.5%), Raillietina cesticillus (12.5%), Raillietina sp. (35.8%), Cotugnia chiangmaii (14.2%) and Cotugnia sp. (32.5%). The prevalence of helminth infections did not differ significantly between male and female chickens. HAT-RAPD analysis, the specific fragment of 400 and 250 bp indicated that Raillietina sp. and Cotugnia sp. found, respectively, differ from other closely related species. This study has confirmed that HAT-RAPD technique can be used to differentiate among related species combined with morphological observations. 相似文献
117.
L D Winward 《Experimental parasitology》1976,40(1):74-76
(1) Extracts of Ascaridia galli, a nematode parasite of domestic fowl (Gallus gallus), contained potent inhibitors of trypsin and chymotrypsin. (2) These inhibitors extracted by TCA and heat treatment and partially purified by DEAE- and CM-cellulose chromatography were found to be proteins of low molecular weight. (3) These inhibitors were nondialyzable, stable up to 15 min at 100 C, and active over a wide pH range (3–10). 8.0 M urea and 0.1 M β-mercaptoethanol had no effect on the inhibitors. (4) Complex formation between the inhibitors and trypsin and chymotrypsin was complete within 60 and 30 sec of contact, respectively. 相似文献
118.
John E. Smith John G. Anderson Christopher W. Lewis Yaseen M. Murad 《FEMS microbiology letters》1992,100(1-3):337-344
Eight-three fungal isolates collected and cultured from the air spora of damp public sector Scottish housing have been screened for cytotoxic properties. A bioassay procedure has been utilised for this purpose involving cytotoxic effects on human embryonic diploid fibroblast lung cells grown as monolayer cultures within the wells of microtitre plates. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] biochemical assay system employed has revealed that 39 (47%) of the moulds investigated possessed spore-associated cytotoxic properties; a value which emphasises the potential health hazards of the continual inhalation of toxigenic fungal propagules by occupants of mouldy houses. Penicillia, the most prevalent fungi found in the internal atmosphere of the domestic environment, accounted for the great majority of cytotoxic strains identified. 相似文献
119.
生活污水对稀有(鱼句)鲫的毒性效应研究 总被引:13,自引:3,他引:10
利用稀有鲫个体小、性成熟时间短、在实验室控制条件下容易饲养等特点 ,将其作为一种毒性实验材料 ,从形态学和组织学水平对生活污水可能产生的毒性效应进行了初步研究。研究结果表明 ,在早期生命阶段 ,高浓度的生活污水对稀有鲫有急性毒性效应。受排污口污水暴露的稀有鲫鱼卵根本无法孵化 ;对处于性腺发育期稀有鲫的暴露则引起肝脏细胞水平上的毒性效应 ,且随污水浓度的增高 ,对鱼体性发育的阻碍效应也越强 ,而整个生命期即使仅暴露于低浓度的生活污水中 ,其个体发育和性发育也均受到影响 ,肝细胞也表现出强烈的毒性效应 相似文献
120.
近年来华东地区家鸭中禽流感病毒的亚型分布 总被引:3,自引:0,他引:3
[目的]为了研究近年来华东地区家鸭中禽流感病毒的亚型分布情况.[方法]对2002-2006年分离自华东地区家鸭的180株禽流感病毒的HA亚型和其中88株禽流感病毒的NA亚型分别进行了测定.[结果]近年来华东地区家鸭中至少存在9种HA亚型和6种NA亚型组成的H1N1,H3N1,H3N2,H3N8,H4N6,H5N1,H5N2,H6N2,H6N8,H8N4,H9N2,H10N3,H11N2共13种亚型的禽流感病毒.[结论]华东地区家鸭中有多种亚型的禽流感病毒分布,应加强家鸭禽流感的监测和防制工作. 相似文献