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111.
The Common Carotid artery Intima-Media Thickness (CCIMT) can reflect systemic atherosclerosis in renal patients on hemodialysis. This study aimed to compare CCIMT measured by color Doppler ultrasonography between two groups including dialytic patients and normal subjects. In this case-control setting, 48 patients with Chronic Kidney Disease (CKD) on hemodialysis (case group) and 46 age and sex-matched healthy subjects (control group) were enrolled in this study. Color Doppler ultrasound was used to measure CCIMT and determine presence of atherosclerotic plaques in carotid bulb in both groups. Various laboratory parameters were also determined. Serum levels of triglyceride, total cholesterol, low-density lipoprotein, fasting sugar, ionized calcium, inorganic phosphorus and magnesium were comparable between the two groups. Hypertension and elevated levels of serum C-reactive protein, as well as the mean levels of serum non-fasting homocysteine and phosphate were significantly higher in the case group. Mean levels of serum high-density lipoprotein and albumin were significantly higher in the controls. Mean maximum CCIMT was significantly higher in the case group than in controls (0.73 +/- 0.15 vs. 0.68 +/- 0.08 mm, p = 0.01) even after adjusting for other confounding variables. Frequency of patients with atherosclerotic plaques in carotid bulbs was not significantly different between case and controls. In conclusion, this study showed that CCIMT is significantly higher in CKD patients on hemodialysis comparing with matched normal counterparts. Furthermore, this difference was independent of other conventional risk factors for atherosclerosis.  相似文献   
112.
The aim of this study was to survey long-term changes in phosphorus (P) fractions in soils in different land uses. Sequential extraction had been used to determine soil P fractionation on the basis of land-use change, i.e. native forest to vineyard and wetland to both alfalfa and wheat at the end of 30 and 20 years, respectively. The highest values of labile-P (L-P) fractions in surface soil layers were observed in the cultivated land. The calcium-bound P was the most affected fraction by land-use change with the lowest amount in the vineyard and the highest amount in the alfalfa land. Conversion of forest to vineyards causes P in the soils to be more vulnerable to transmission; thus, the least amount of total P (T-P) in vineyard may be attributed to the removal of sediment and sediment bond P from runoff in response to land-use changes. Average L-P in alfalfa land was two times more than that in vineyard. Results showed that 44.5% of T-P in native land was stored in surface layer; besides, the portion of the arable surface horizon in T-P sequestration was 33%.  相似文献   
113.
Growing Fe-efficient genotype(s) could be considered as a preferred genetic approach to tackle the widespread constraint of Fe-deficiency-/lime-induced chlorosis in crop grown on alkaline soil. This study aimed to investigate morphological and physiological traits linked to expression of Fe deficiency among four corn (Zea mays) including sweet (Z. mays sacchrata cvs. H403 and H404) and grain (Z. mays indentata cvs. H500 and H700) hybrids grown in nutrient solution using two Fe concentrations (5 and 50 µM Fe-ethylenediaminetetraacetic acid (Fe-EDTA)). Significant variation was found among studied hybrids in their tolerance to Fe-deficiency stress. Sweet corn hybrids were more sensitive to Fe deficiency as compared with grain corn hybrids and greater reduction was observed in their shoot dry matter at the 5 µM Fe-EDTA treatment. The greatest decrease in plant height, leaf area, and root and shoot dry matter weight under Fe-deficiency condition was found for H403 hybrid. No significant correlation was found between shoot and root Fe concentration with crop tolerance to Fe deficiency. Furthermore, different response of corn hybrids to Fe deficiency is an important factor, which has to be considered in Fe fertilizer recommendation as well as breeding programs.  相似文献   
114.
A greenhouse experiment was carried out to determine copper (Cu) desorption characteristics in ten bulk and rhizosphere soils (Typic Calcixerepts) amended with sewage sludge (1% w/w) using rhizoboxes. The kinetics of Cu desorption in the bulk and the rhizosphere soils were determined after successive extraction with DTPA‐TEA and 10 mM citric acid in a period of 1 to 504 h at (25 ± 1)°C. The results show that Cu extracted after 504 h using DTPA‐TEA were significantly (P < 1%) lower in the rhizosphere than the bulk soils. However, Cu extracted after 504 h using citric was significantly (P < 1%) higher in the rhizosphere than in the bulk soils. The results illustrated that, on average, citric acid extracted 56% more Cu from the bulk soils than DTPA‐TEA, and citric acid extracted 85% more Cu from the rhizosphere soils than DTPA‐TEA. Desorption kinetics of Cu in the two extractants was well described by power‐function, parabolic diffusion, and first‐order equations. The results show that a 10 mM citric acid extractant may be recommended to determine the kinetics of Cu desorption in calcareous soils amended with sewage sludge.  相似文献   
115.
An experiment was conducted to determine whether some non‐nutritive feed additives (NNFA) could block the adverse effects of aflatoxin (AF) on growth performance and physiological parameters of Cobb broilers throughout the period from 1 to 21 day of age. There were eight treatments consisting of two levels of AF at 0 and 200 ppb and four NNFA within each AF level. These additives included mannan oligosaccharides (MOS) at 2 g/kg diet, hydrated sodium calcium aluminosilicate (HSCAS) at 2 g/kg diet and Lactobacillus acidophilus (Lac) at 2 g/kg diet. At 21 day of age, five chickens of each treatment were slaughtered to study dressing percentage and relative weight of inner organs and glands. AF had a significant negative effect on body weight gain (BWG), and feed intake, while impairing feed conversion ratio (FCR). Aflatoxin significantly increased percentage liver, lymphocyte (%), monocyte (%), serum triglyceride level, and the aspartate aminotransferase (AST), and alanine aminotransferase (ALT), concentrations while decreasing dressing percentage, intestinal percentage, white blood cells (WBCs), red blood cells (RBCs), haemoglobin (Hgb), packed cell volume (PCV), heterophil (%), heterophil/lymphocyte ratio, total serum protein and serum albumin. Aflatoxin adversely affected the morphology of the liver, bursa and the thymus. There was a significant interaction between AF and NNFA on the relative weights of liver, heart and intestine. Lac completely blocked the negative effects of AF on the percentage liver and the heart and partially on the intestine. In conclusion, Lac was most effective in reversing the adverse effects of AF on growth and FCR and on the percentage, functions and morphology of the liver. Hydrated sodium calcium aluminosilicate also improved the economic traits of broilers but was less effective than Lac and more effective than MOS.  相似文献   
116.
采用开都河流域下游焉耆县、和静县、和硕县三个气象站1960-2009年气温和降水观测资料,以线性趋势函数,M-K突变检验等方法,分析开都河流域下游气温和降水的年际变化、季节变化特征。研究结果表明:(1)焉耆县、和静县与和硕县的年平均气温呈上升趋势,年平均气温线性拟合增长率分别为0.366℃·10a-1、0.256℃·10a-1、0.033℃·10a-1。(2)和硕县月平均最低气温呈现下降趋势,而焉耆县与和静县平均最高气温、最低气温均呈上升趋势;从季节年际变化来看,三个县四季气温均有增加趋势,冬季增温明显,秋季平均气温的年际变化幅度与年平均气温的年际变化幅度相似。(3)三个县年降水量距平值呈下降-上升-下降特征,降水量有微弱增多趋势。(4)和静县与和硕县两站气温异常,焉耆县降水异常,气温突变均出现在20世纪90年代,而且突变发生较频繁。  相似文献   
117.
This study was designed to examine the main effects and interactions of time, presence of antibiotics, and type of sperm activators on the fertilization capacity (eyeing rate) of refrigerated semen of rainbow trout, Oncorhynchus mykiss. The semen samples were stored in the presence or absence of 250 IU ml?1 penicillin and 250 μg ml?1 streptomycin sulfate. Freshwater and a saline solution were used as sperm activators. The semen samples were stored at 2–3°C and fertilized after 0, 6, 8, 12, 19, and 25 days of storage. Fertilizing capacities of semen samples stored in the presence of antibiotics (63.8 ± 5.6%) were significantly (p < 0.05) higher than those stored in the absence of antibiotics (46.2 ± 6.7%). Also, the fertilizing capacities of stored semen samples activated using saline solution (70.7 ± 5.7%) had significantly (p < 0.05) higher values than those activated using freshwater (39.3 ± 5.9%). Semen samples stored in the absence of antibiotics completely lost fertilizing capacity within 19 days of storage. After 25 days of storage in the presence of antibiotics, induction of fertilization using freshwater and saline solution resulted in 0% and 79.8 ± 1.7% fertility, respectively.  相似文献   
118.
Development of artificial crayfish egg incubation is a milestone in intensive culture of crayfish as commercially important freshwater animals. This study evaluated experimental treatments combining continuous UV lighting, a non‐chemical antifungal treatment, with an initial formaldehyde bath for noble crayfish (Astacus astacus) eggs incubated in semi‐recirculating systems, which requires less than 1 per cent the amount of water necessary for conventional flow‐through systems. The one‐time administration of a pre‐incubation bath to reduce formaldehyde exposure was ineffective. Ultraviolet irradiation of recirculating water provided poor results (13.5% and 35.2% final survival rates to stage 2 juveniles) and led to deteriorating water quality. An inability of hatchlings to successfully moult and the occurrence of limb deformities was observed in UV‐treated groups, and juvenile mortality was found across all experimental treatments.  相似文献   
119.
120.
The main propose of the present study was to determine the effects of diazinon on the activity and gene expression of glutamate dehydrogenase (GDH) as the key enzyme of Langerhans islet for secretion of insulin. Diazinon was administered intraperitoneally at doses of 15, 30, and 60 mg/kg. Langerhans islets were isolated from the pancreas of rats by a standard collagenase digestion, separation by centrifugation, and hand-picking technique. The activity and gene expression of the mitochondrial GDH was determined in the islets homogenates. Glutamate, C-peptide, and insulin were determined in plasma.Diazinon at all tested doses (15, 30, and 60 mg/kg) significantly (p < 0.01) decreased plasma insulin after 1 h while the values did not differ from control when examined after 18 h. Diazinon at all tested doses (15, 30, and 60 mg/kg) significantly (p < 0.01) increased concentration of C-peptide both 1 and 18 h post-administration. Diazinon at all tested doses (15, 30, and 60 mg/kg) significantly (p < 0.05) increased production of glutamate while the values did not differ from control when tested after 18 h. Administration of diazinon at doses of 30 and 60 mg/kg significantly (p < 0.001) increased activity of GDH after 1 h while all doses of diazinon increased GDH activity when measured after 18 h. Diazinon at dose of 60 mg/kg significantly (p < 0.01) decreased expression of GDH gene 18 h post-administration.It is concluded that GDH is a component of diazinon-induced changes in release of improper insulin.  相似文献   
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