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101.
伊犁河流域地下水埋深与TDS时空变异及水化学特征分析   总被引:1,自引:0,他引:1  
采用地统计学经典理论分析了伊犁河谷典型区域在不同时期地下水TDS和埋深在时间和空间上的变异特征,对研究区浅层地下水TDS不同时期(2008—2009年)的实测数据进行了半方差函数分析,地下水埋深和TDS服从都对数正态分布。地下水TDS和埋深在时间和空间上存在明显的变异性,地下水TDS在研究区中部和北部有增加的趋势;地下水随时间从南到北盐渍化加重方向发展;地下水各项离子浓度都在积聚。利用统计软件DPS7.5,Surfer8.0和Arcgis9.2等软件绘制了地下水TDS和埋深空间分布格局图,为该地区地下水资源的管理以及防止盐渍化提供理论依据。  相似文献   
102.
Groundnut is an annual legume and important oilseed crop in the world. In order to evaluate the influence of the topping height and application methods of Zinc (Zn) and Calcium (Ca) nano-chelates on quantitative and qualitative characteristics of groundnut, these experiments were carried out during the 2016–2017 cropping seasons on groundnut in Iran. Both foliar and in soil applications of Zn and Ca nano-chelates improved groundnut yield. Foliar application of Zn nano-chelate in combination with topping the main stem 20 cm above the ground produced the highest 100-seed weight (82.19 g), seed yield per unit area (2722.5 kg.h?1), harvest index (57.53%), biological yield (6540.00 kg.h?1), oil yield (1486.76 kg.h?1), protein yield (742.66 kg.h?1), seed Zn content (12.08 ppm) and Ca content (35.86 ppm). The application of Zn nano-chelate had different positive influences on vegetative and reproductive growth of groundnut plants. Generally, optimizing of the nutritional status in groundnut plants with Ca and Zn supplements is recommended to enhance the quantitative and qualitative yield of groundnut.  相似文献   
103.
Purpose

Rapid industrialization in China accelerated environmental pollution by xenophores and trace metals particularly cadmium. Numerous studies have been conducted to address soil contamination using organic and inorganic amendments under pot or incubation conditions, but few were performed under field conditions, particularly in the wheat-growing areas. This study aims to investigate the effectiveness of pre-applied soil amendments for Cd immobilization, changes in soil pH, and metal uptake by wheat.

Materials and methods

In this study, 12 treatments, i.e., control (CK), lime, DaSan Yuan (DASY), DiKang No. 1 (DEK1), biochar, Fe-biochar, Yirang, CaMgP, and green stabilizing agents (GSA-1, GSA-2, GSA-3, and GSA-4), were evaluated for Cd immobilization in incubation and field experiments. Changes in soil pH and available metal content with amendments were monitored from 30 to 150 days of incubation. Single extraction method and DTPA-extractable and sequential extraction procedures were employed to assess the variations in available Cd contents of field soil. The impact of soil amendments on Cd uptake and bioaccumulation in food part of wheat was measured at harvesting stage in a contaminated site.

Results and discussion

Lime treatment increased soil pH by 32% and reduced available Cd to 0.213 mg kg?1, as compared to CK (control) in the incubation experiment (0.343 mg kg?1). Effects of the amendments on wheat growth, soil pH, and Cd phytoavailability were reported. Wheat biomass was highest in treatment GSA-2 (13,880 kg ha?1) and GAS-4 resulted in an increase in grain yield (5350 kg ha?1). Soil pH of the treated field at harvesting stage increased up to 6.50, 6.50, and 6.47 by application of GSA-4, GSA-2, and lime, respectively. Cadmium contents in wheat grain were declined significantly in the treatments of GSA-2, GSA-4, and lime.

Conclusions

Results of this study revealed a significant decrease in available Cd concentration with the application of amendments. Composite amendments were more effective in terms of metal uptake and bioaccumulation in wheat. In addition, our results indicate the effectiveness of composite amendments in stabilizing Cd in contaminated soil.

  相似文献   
104.
In order to investigate the effects of different iron (Fe) sources (nano iron (Fe)-chelate, Fe- ethylenediamine-di(o-hydroxy phenyl acetic acid (EDDHA) and iron (II) sulfate (FeSO4)) on lettuce (Lactuca sativa) growth in alkaline solutions, an experiment was arranged in hydroponic system. This study showed that leaf Fe content and overall plant growth was significantly increased by Fe-chelate application, and the highest values of leaf Fe, plant pigments and vegetative growth were recorded in plants treated with nano Fe-chelate. The lowest Fe, chlorophyll, carotenoids and soluble sugars in leaves were observed in FeSO4 treatment. There were no difference in soluble sugars contents of plants between nano Fe-chelate and Fe-EDDHA treatments. Fertilization of lettuce plants with different Fe-chelate sources had a beneficial effect on the manganese (Mn) and zinc (Zn) uptake in plants. It is concluded that application of chelated form of Fe (especially nano Fe-chelate) must be performed in hydroponic system with alkaline water, to overcome Fe deficiencies and to make better nutritional status.  相似文献   
105.
Eurasian Soil Science - Arid and semiarid soils of southern Iran may fix a large content of applied potassium (K), but the fixed K may be gradually supplied to plants. Sixteen representative soils...  相似文献   
106.
In this study, cryopreservation feasibility of Persian sturgeon (Acipenser persicus) and the effect of different doses of 2‐hydroxypropyl‐beta‐cyclodextrin on thawed spermatozoa quality (motility duration and motility percentage) were investigated. For freezing, semen of seven male individuals was pooled in equal volumes and diluted with 4°C [Tris‐HCl (100 mM), pH = 8, DMSO 10%] extenders containing 0, 5, 10, 15 mM of HβCD in a ratio of 1:1(semen/extenders). Then semen was filled into 0.5‐mL straws, and was frozen with vapour of liquid nitrogen at 4‐cm above surface of liquid nitrogen. After 3 min, straws were plunged in to liquid nitrogen. Thawing was performed at 40°C water baths for 15 s. Motility duration of the 10 mM HβCD treated spermatozoa at days 14 (228.98 ± 16.39) and 56 (199.66 ±21.78) were longer than other treatments. In day 56, the motility percentage in treatment with 10 mM was significantly higher (16.14 ± 2.54) (P < 0.05) compared with 5 mM treatment (8.75 ± 2.47) (P < 0.05). Therefore, it is recommended that 10 mM of HβCD can be used as an additive cryoprotectant for increasing cryopreserved spermatozoa quality in this species.  相似文献   
107.
108.
In this study, the invasive and noninvasive diagnotic tests were compared to choose the appropriate test for diagnostice of H. pylori infection. Helicobacter pylori (H. pylori) is a human pathogen that causes chronic gastritis, has a role in gastric and duodenal ulcer, is involved in gastric carcinogenesis and is regarded as a possible important factor in at least a subset of patients with functional dyspepsia. The diagnosis of H. pylori is an essential element in the management of many common gastrointestinal pathologies. The assessment of each routine invasive and noninvasive test is important. We studied a total of 127 outpatients for the detection of H. pylori infection. The presence of H. pylori infection by invasive tests containing the Rapid Urease Test (RUT), histology (Giemsa staining) and culture in 127 patients. Patients who were positive in culture, or two tests from four tests, invasive and noninvasive, were considered to have H. pylori infection. In noninvasive tests, we evaluated anti-H. pylori IgG and anti-CagA antibodies using commercial Enzyme-Linked Immunoassay (ELISA) and Western blot in dyspeptic patients. Eighty five out of the 127 patients were positive for H. pylori. Helicobacter pylori IgG seropositivity and 35 out of the 127 patients were positive for immunoblot. RUT had sensitivity, specifity and accuracy of 96, 80 and 90.5%, respectively; for Elisa these were 85.2, 33 and 70.5%, respectively and for ELISA with immunoblotting they were 65, 45 and 58.8%, respectively. The results of this study suggest that noninvasive tests (ELISA, immunoblotting) have the lowest and RUT with histology have the highest accuracy. These earlier tests can not be used for accurate infection diagnosis.  相似文献   
109.

Background:

Coronary artery disease (CAD) is a multifactorial and heterogenic disease. Recently, genome-wide association studies have reported that rs1333040 (C/T) and rs1004638 (A/T) single nucleotide polymorphisms (SNPs) in the 9p21 locus have very strong association with CAD. This study aimed to examine these associations in Southwest of Iran.

Methods:

Blood samples were collected from 200 CAD patients and 110 healthy individuals with no CAD. The association of two SNPs with CAD was evaluated by PCR and restriction fragment length polymorphism.

Results:

Chi-square test showed no association between rs1333040 SNP and CAD (X2: 4.66, df: 2, P=0.09). Also, there was no association between rs1004638 SNP and CAD (X2: 0.27, df: 2, P=0.88).

Conclusion:

No association was observed between rs1333040 and rs1004638 SNPs in the 9P21 region and CAD in Southwest of Iran. Key Words: Coronary artery disease, Single nucleotide polymorphisms, Genetic association study, Iran  相似文献   
110.
The aim of the present study was to evaluate the potential effects of olive leaf (Olea europea L.) extract (OLE) on common carp (Cyprinus carpio) health in response to ambient ammonia toxicity. Fish were fed with experimental diets containing OLE (0, 1, 5 and 10 g/kg) for 60 days followed by a 3‐hr challenge with ammonia (0.5 mg/L unionized ammonia‐N). Results showed that haemoglobin levels, differential leucocyte counts and mean corpuscular haemoglobin concentration were not affected by dietary OLE levels and ammonia challenge. Ammonia challenge significantly increased red blood cells and decreased blood mean corpuscular volume, mean corpuscular haemoglobin, plasma lysozyme, complement and bactericidal activities. Plasma lysozyme, complement and total immunoglobulin values improved by 5 and/or 10 g OLE/kg supplementation. Before the ammonia exposure, the 5 and 10 g OLE/kg treatment significantly increased blood white blood cell, but there was no significant difference among the treatments after the ammonia exposure. Ammonia exposure significantly increased plasma malondialdehyde levels; however, 1 and 5 g OLE/kg treatments had significantly lower values compared to the other treatments. The present results suggest that 1 g OLE/kg diet may improve fish health and reduce the adverse effects of ammonia toxicity on common carp.  相似文献   
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