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51.
本文对阿克苏流域的三座大型平原水库,即上游水库、胜利水库和多浪水库在枯水期和丰水期的水质进行了监测分析,比较了各水库不同水期水质现状,并对监测指标进行了因子分析。结果表明:三座水库枯水期污染程度比丰水期高。水质污染物可分抑制性因子(F1),包括NH3-N、SO42-、Cl-和矿化度以及富营养性污染指标(F2),包括TN、TP和CODMn。目前水库水质主要由第一因子F1决定。枯水期水质污染大小次序为胜利水库>上游水库>多浪水库,而丰水期为多浪水库>胜利水库>上游水库。三座水库水质与引水河流的水质污染指标之间存在极显著相关性。  相似文献   
52.
新疆经济发展与环境污染关系研究   总被引:2,自引:0,他引:2  
利用新疆1990-2005年经济与环境统计数据,建立了人均GDP与典型环境指标关系计量模型并分析了两者之间关系。分析结果表明:该时段新疆人均GDP与环境指标之间没有明显的"倒U"型关系;工业废水排放量、工业废气排放量、工业粉尘排放量和工业固体产生量随着经济的发展总体呈现出上升趋势,原因是新疆工业发展较快,还是粗放型为主,环境污染治理投资主要用于提高污染物处理率和达标排放率;仅有工业烟尘排放量呈现出随经济发展降低趋势;新疆目前现状符合经济发展初期随着经济发展环境质量下降的理论。  相似文献   
53.
The aim of present study was to know about past cultivation of pseudocereals and millets in Kashmir province of Indian state of Jammu and Kashmir. These crops which were cultivated throughout Kashmir in plains as well as in hilly areas are buckwheat species, Fagopyrum esculentum and Fagopyrum tataricum; amaranth and minor millets, Setaria italica and Panicum miliaceum. In Kashmir these are now forgotten crops. Few plants of amaranth (Amaranthus caudatus) are still grown in almost every kitchen garden in Kashmir. The crop is however not cultivated commercially neither in Kashmir nor in Ladakh or Jammu provinces of the state. Our study has revealed that cultivation of all these crops has been abandoned some five or six decades back throughout Kashmir excepting in few farflung hilly areas in north Kashmir. Currently these crops are also cultivated in Ladakh, but here also their cultivation is dwindling rapidly. The reasons as to why farmers have abandoned these crops and are increasingly losing interest in these biological assets in the areas of their present cultivation have been discussed. There is a need to rescue these threatened crops which have many advantages besides, being nowadays categorized as quality health foods. During our survey in Ladakh province we have collected 30 germplasm accessions of these crops from various locations. These have been deposited in National Seed Gene Bank at NBPGR, New Delhi for conservation and evaluation. The improvement and revival of these lost crops has the potential to diversify agriculture, food system and income of the poor farmers and have the ability to ensure food security and livelihood of the people in this Himalayan state under future adverse climatic conditions.  相似文献   
54.
We have isolated and purified two trypsin inhibitors from broad bean(Vicia faba L.). On the evidence of acrylamide gel electrophoresis these two inhibitors, labelled BBTI-1 and BBTI-2, are pure and distinct. Trypsin inactivation and stability studies indicate that BBTI-2 has the greater specific activity and is the more heat stable than BBTI-1. The amino acid pattern confirms the distinctness of the two inhibitors. From qualitative evidence it is inferred that two inhibitors are not simple proteins, but possibly glycoproteins which could explain the stability characteristics observed.
Zusammenfassung Wir haben aus Dicken Bohnen(Vicia faba) zwei Trypsin-Inhibitoren isoliert und gereinigt. Nach den Befunden der Acrylamidgel-Elektrophorese sind diese beiden Inhibitoren, mit den Bezeichnungen BBTI-1 und BBTI-2, rein und von einander verschieden. Trypsin-Inaktivierungs- und Stabilisierungs-Versuche ergaben, daß BBTI-2 eine größere spezifische Aktivität besitzt und hitzestabiler ist als BBTI-1. Die Aminosäurenzusammensetzung bestätigt die Verschiedenheit der beiden Inhibitoren. Aus den qualitativen Befunden kann gefolgert werden, daß zwei Inhibitoren nicht einfache Proteine sind, aber möglicherweise Glycoproteine, die den beobachteten stabilen Charakter erklären würden.


Paper presented at the conference of the International Association for Quality Research on Food Plants (CIQ) held in common with the Deutsche Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) e.V. (DGQ) in Berlin on 5th October 1972.  相似文献   
55.
Genetic Resources and Crop Evolution - The Saccharum species members are extremely complex allopolyploids. In this study, sixty Saccharum spp. hybrids were analyzed using simple sequence repeat...  相似文献   
56.
This experiment investigated the effect of a supplementary dietary source (flaxseed) on egg yolk cholesterol contents and fatty acid profile. Flaxseeds at three different levels (5, 10, and 15%) were supplemented to 84 Rhode Island Red × Fayoumi cross layers during 21–24 weeks of age. The birds were divided randomly into four groups. Flaxseeds were supplemented in the diet at the level of 5% (FS‐5), 10% (FS‐10), and 15% (FS‐15), and one group served as the control (FS‐0). Cholesterol content of eggs was not significantly affected by flaxseed. The amount of monounsaturated fatty acids was significantly decreased with the increase in the flaxseed level, and the highest reduction was observed in FS‐15. The highest total polyunsaturated fatty acid (PUFA) and total omega‐3 PUFA were recorded in FS‐15. These findings reflect that unsaturated healthy fatty acid content in poultry eggs can be increased with dietary supplementation of flaxseed.  相似文献   
57.
The objective of this study was to determine the effects of soybean meal (SBM) or spray-dried blood meal (BM) supplementation of diets based on untreated (UNT-WS) or alkaline hydrogen peroxide-treated wheat straw (AHP-WS). A 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments was used. Variables included nutrient digestion and flow to the duodenum. Four Simmental steers (average weight 477 kg) fitted with ruminal and duodenal cannulas were fed 65% UNT-WS or AHP-WS based diets in 12 equal portions daily. Diets were formulated to contain 10% CP. Chromic oxide was used as the digesta flow marker and purines were used as the microbial marker. There were no straw type x protein source interactions. Total tract and ruminal OM digestibility were approximately 25% greater (P < .04) when AHP-WS was fed than when UNT-WS was fed. Source of protein did not affect (P > .10) OM or fiber digestion in the rumen or total tract. Ruminal digestion of NDF and ADF was increased (P < .01) by 51 and 40%, respectively, when AHP-WS was fed than when UNT-WS was fed. Main effect means (P > .10) for N flow to the duodenum as a percentage of N intake were 128.2, 142.5, 133.4, and 137.6 for UNT-WS, AHP-WS, SBM, and BM treatments, respectively. Despite increased (P < .01) ruminal OM digestion for AHP-WS, microbial N flow to the duodenum was greater (P < .01) when UNT-WS was fed than when APH-WS was fed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
58.
Foot-and-mouth disease (FMD) is one of the most devastating animal diseases, affecting all cloven-hoofed domestic and wild animal species. Previous studies from our group using DNA vaccines encoding FMD virus (FMDV) B and T cell epitopes targeted to antigen presenting cells, allowed demonstrating total protection from FMDV homologous challenge in those animals efficiently primed for both humoral and cellular specific responses (Borrego et al. Antivir Res 92:359-363, 2011). In this study, a new DNA vaccine prototype expected to induce stronger and cross-reactive immune responses against FMDV which was designed by making two main modifications: i) adding a new B-cell epitope from the O-serotype to the B and T-cell epitopes from the C-serotype and ii) using a dual promoter plasmid that allowed inserting a new cistron encoding the anti-apoptotic Bcl-xL gene under the control of the internal ribosomal entry site (IRES) of encephalomyocarditis virus aiming to increase and optimize the antigen presentation of the encoded FMDV epitopes after in vivo immunization. In vitro studies showed that Bcl-xL significantly prolonged the survival of DNA transfected cells (p?<?0.001). Accordingly, vaccination of Swiss out-bred mice with the dual promoter plasmid increased the total IgG responses induced against each of the FMDV epitopes however no significant differences observed between groups. The humoral immune response was polarized through IgG2a in all vaccination groups (p?<?0.05); except peptide T3A; in correspondence with the Th1-like response observed, a clear bias towards the induction of specific IFN-γ secreting CD4+ and CD8+ T cell responses was also observed, being significantly higher (p?<?0.05) in the group of mice immunized with the plasmid co-expressing Bcl-xL and the FMDV B and T cell epitopes.  相似文献   
59.
污灌对土壤-植物体系中养分迁移的影响   总被引:7,自引:1,他引:6  
本文就污灌对土壤-植物体系中有机质及N、P、K等的含量变化的影响进行了研究。结果表明:污灌可使土壤K素的含量增加幅度最大为27.0%,但由于氨的挥发、硝化及反硝化作用易造成氮素损失。土壤-植物体系对有机污染物有较强的净化能力。0~60!的土层对有机质、N、P有一定的富集作用,有利于植物吸收利用。而植物对K素的吸收利用率较低。植物对养分的吸收积累顺序为叶>根>茎,P>N>K素。从不同植物的吸收情况来看,榆树对养分的吸收则明显优于苹果树和山桃。相关分析表明:表层土壤中有机质与N、P、K含量密切相关。  相似文献   
60.
Plant growth promoting rhizobacteria (PGPR) promote the plant growth by various direct and indirect mechanisms. The present study was undertaken to isolate and characterise the PGPRs of plum (Prunus domestica) rhizosphere in Pakistan. A total of 95 rhizobacteria were isolated, out of which 40 strains were selected on the basis of morphological, biochemical and Gram staining characteristics. The selected isolates were screened for in vitro plant growth promoting potential and were subsequently evaluated for host plant growth promotion. The selected isolates demonstrated strong lytic enzymatic activities and were able to produce ammonia, siderophore, Hydrogen cyanide along with capability of phosphate solubilisation. Moreover, the results showed a significant growth suppression of pathogenic Fusarium oxysporum and Rhizoctonia solani in an in vitro assay. The plant microbe interaction study was carried out using 11 most efficient rhizobacterial strains inoculated to roots of plum plants. The inoculated PGPRs significantly augmented the leaves number per shoot, shoot diameter, shoot length and plant height. The inoculation also significantly increased the chlorophyll contents of leaves, concentration of micro and macro nutrients compared with control. The current study shows the importance of these selected PGPRs as bio-fertilizer to improve the health and productivity of plum species in Pakistan.  相似文献   
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