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排序方式: 共有319条查询结果,搜索用时 93 毫秒
41.
Amir Abbas Bazyar Lakeh Hamid Farahmand Werner Kloas Alireza Mirvaghefi Achim Trubiroha Brian C. Peterson Sven Wuertz 《Aquaculture International》2016,24(1):11-21
Juvenile rainbow trout (Oncorhynchus mykiss) were passively immunized by intraperitoneal immunization against somatostatin-14 (SS-14) using an antibody originating from egg-laying chicken (Gallus domesticus). Fish were immunized weekly (0, 7, 14, 21, 28, 35 days) with chicken egg yolk-derived immunoglobulin (IgY) against SS-14 (1:25 IgY, 5 mg mL?1), and growth performance, feed utilization as well as plasma concentrations and mRNA levels of growth hormone (GH) and insulin-like growth factor I (IGF-I) were compared to the control group that received placebo immunization with PBS. Passive immunization significantly increased weight gain of treated fish (67.7 ± 7.4 g) compared to the control group (40.1 ± 2.0 g) after 35 days (p < 0.05). Feed conversion ratio (FCR) was significantly improved in the immunized fish (0.7 ± 0.08) compared to control group (1.2 ± 0.06) (p < 0.05). The concentrations of GH and IGF-I in the blood plasma showed no significant differences between the fish treated with anti-SS-14 and those of control during the treatment (p > 0.05). In both groups, GH levels decreased over the 35 days of the experiment (p < 0.05). However, IGF-I level during the period of treatment remained unchanged in both control and immunized fish with the anti-SS-14. Similarly, no changes were observed in pituitary GH and liver IGF-I mRNA levels between treatment and control at each sampling time (p > 0.05). There was no indication of a cumulative, long-lasting effect of repeated immunization on GH or IGF-I plasma concentrations or mRNA expression. The present study shows that a passive immunization of rainbow trout against SS-14 using a chicken egg yolk-derived SS-14 antibody could increase growth rate and improved FCR. 相似文献
42.
Background:
Our previous in vivo studies confirmed that ICD-85, as an anticancer agent, was able to prevent further growth of breast tumors and expand the life expectancy of mice with breast cancer.Methods:
Blood collection was carried out before, 1, 3, and 6 hours after ICD-85 injection. Sera were used to determinate the cardio and hepatic enzymes levels, including ALT, AST, LDH, CPK, and Ck-MB. Coagulation factors such as PT and PTT were also assayed. ECGs of all rabbits were recorded during the experiment.Results:
ECG results showed that the injection of 50 and 100 µg/kg ICD-85 into healthy rabbits has no significant effect on heart function while the injection of 150 to 200 µg/kg ICD-85 caused ECG wave changes and mild bradycardia without toxic effects on heart. After ICD-85 injection (concentrations below 100 µg/kg), no significant increase was observed in liver and cardiac enzymes (ALT, AST, LDH, CPK, and CK-MB). However, the concentration of 150 µg/kg and above caused a rise in the enzymes. Comparison of the PT and PTT before and after ICD-85 injection showed no significant clotting time at any concentrations below 200 µg/kg.Conclusion:
Based on the results obtained in the present study as well as our previous reports, ICD-85 at concentrations below 100 µg/kg seems to have no significant effect on the serum enzymes as indicators of hepatotoxicity and cardiotoxicity in healthy rabbits. However, to confirm this conclusion, more detailed surveys on heart and liver is needed to be carried out. Key Words: ICD-85, Electrocardiogram, Anticancer 相似文献43.
Excessive soil compaction has negative effects for agriculture and the environment. Measurement of soil strength is a common indirect measure of soil compactness. In the context of precision farming, on-the-go soil mechanical resistance measurements using single- and multiple-tip horizontal sensors have been developed. It has been reported that there was a significant relationship between soil mechanical resistance values measured with both vertically operated cone penetrometer and horizontally operated sensors only for relatively deep layers. It was hypothesized that the differences in horizontally measured soil resistance in different soil layers could be explained by different failure modes. The objective of this research was to develop a horizontal soil mechanical resistance sensor and to observe the failure mode in front of it while penetrating soil at three different depths. A single-tip horizontal penetrometer was equipped with a 30° prismatic tip and had a base area of 324 mm2. The prismatic tip was mounted horizontally to an S-shaped load cell housed inside a shank. A data-logging system was also developed to record measurements with 10 Hz sampling rate. The sensor was tested in a field with silty clay loam soil at three depths of 20, 25 and 30 cm. Cone index (CI) values were obtained with 1 cm depth increments and 1 m horizontal intervals along each transect for comparison using a standard cone penetrometer. The results showed that average horizontal soil mechanical resistance index (HRI) values for both depths of 20 and 25 cm were similar due to the brittle failure mode in both cases. However, when the tip was operated below the critical depth of the sensor, the value of HRI at 30 cm depth increased three times when compared with 20 or 25 cm depth values. This was due to change in failure mode from brittle to compressive mode below the critical depth. There was a significant relationship (R2 = 0.75) between HRI and CI for the 30-cm depth, whereas for shallower depths the relation was not significant. It can be concluded that the correlation between measurements obtained with the vertically and horizontally operated penetrometers would be significant as long as both produced the same soil failure mode. 相似文献
44.
Effect of dietary tryptophan (TRP) on copper toxicity was investigated in common carp, Cyprinus carpio. Fish were randomly distributed into two triplicate treatments (control and TRP) and fed control (TRP?=?3.1?g?kg(-1)) or TRP (TRP?=?8.1?g?kg(-1)) diets over a 2-week period. Then, both treatments were subjected to 10?mg?l(-1) copper sulfate over a 7-day period. Mortality and serum cortisol, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), sodium, potassium, and chloride levels were recorded at 0, 24, 72, 120, and 168?h post-copper exposure. There was no mortality in the TRP group, whereas the control group mortality was started at 120?h post-copper exposure (21.7?±?7.6?%) and reached 61.7?±?10.4?% at the end of the experiment. Cortisol, glucose, ALT, and AST levels significantly (P?0.05) increased after copper exposure in both groups; however, the control group showed significantly higher levels than the TRP group. In both groups, sodium decreased after copper exposure and did not return to the pre-exposure values. Potassium levels significantly increased 24?h post-copper exposure in both groups and remained significantly elevated in the control group at 72?h, when fell to the pre-exposure values in the TRP group. No significant changes were observed in the chloride levels in any groups. It is concluded that dietary TRP is capable to increase common carp tolerance to copper toxicity via mitigating copper-induced stress rather than restoring gill dysfunction and hydromineral imbalance. 相似文献
45.
Ghulam Abbas Tariq Manzoor Khan Jehanzeb Farooq Abid Mahmood Rana Nadeem Abbas Wajad Nazeer Amjad Farooq Zuhair Hasnain Muhammad Naeem Akhtar 《Frontiers of Agriculture in China》2011,5(4):443-449
This research was conducted to explore genetic material that can yield better under salt stress conditions. The experiment
was laid out using 27 upland cotton genotypes in a RCBD 2 factorial arrangement with two replications. Saline water (NaCl
at 20 dS/m) was applied after satisfactory emergence was achieved. The crop was raised to maturity and data relating to yield,
fiber quality and ionic traits were recorded. Analysis of variance showed significant variations in the germplasm. Plant height,
bolls per plant, boll weight, GOT%, staple length, staple strength, K+ and K+/Na+ ratio under salinity stress showed a highly significant correlation with seed-cotton yield. The highest direct effect on
seedcotton yield per plant was exhibited by bolls per plant and boll weight. The results from the correlation and path coefficient
analyses revealed that although the K+/Na+ ratio had a strong positively significant association with seedcotton yield, its direct effect on the seed-cotton yield was
negative and thus selection on the basis of K+/Na+ may not be fruitful. Hence, only indirect selection through bolls per plant and boll weight may be effective in increasing
the seedcotton yield per plant under salinity stress. 相似文献
46.
Muhammad Abbas Javaid Ahmed Shah Muhammad Irfan Muhammad Yousuf Memon 《Journal of plant nutrition》2018,41(12):1522-1533
A solution culture study was conducted to compare the phosphorus (P) remobilization efficiency of four wheat cultivars under induced P deficiency. Wheat cultivars, i.e. Sarsabz, NIA-Sunder, NIA-Amber and NIA-Saarang were initially grown on adequate P nutrition for 30 days and then exposed to P-free nutrient solution for next 15 days to study P remobilization. Completely randomized design (CRD) with ten replicates per cultivar was employed. Cultivars varied for biomass production, P concentration, P uptake, and P utilization efficiency at both harvests. Overall, more than 75% of absorbed P was mobilized from older leaves to younger leaves as well as roots of all cultivars during P-omission period. However, cultivars could not produce significant variations (P < 0.05) in P remobilization, which implied that P remobilization was only a stress response to P deficiency in wheat cultivars and it could not be related to P utilization efficiency of these cultivars. 相似文献
47.
48.
Arezoo Soltani Prem L. Sankhayan Ole Hofstad Farshid Eshraghi Abbas Arabmazar 《Small-Scale Forestry》2017,16(3):347-365
Construction of new roads in rural areas is closely linked to market accessibility and economic growth. It also leads to exploitation of natural resources that may accelerate deforestation. These conflicting effects of an improved road network on rural development and depletion of forest resources present a serious challenge to policy makers interested in sustainable development. This paper investigates the effects of road networks on biological and socio-economic behaviour. The analysis was conducted by using a non-linear bio-economic model for a community in southern Zagros, Iran where they manage the adjoining forest according to traditional rules. Data for the model were obtained through village surveys and published resources. The model followed a holistic approach by incorporating a number of livelihood activities, such as, crop cultivation, goat husbandry, charcoal production and hiring out of community labour, along with several logical resource constraints. It was run over a period of 45 years. The results showed that new roads can either fuel forest degradation or contribute to forest protection depending on the choice of policy options. The study concludes that construction of new roads should be accompanied by policies aimed at higher state controls over newly accessible forest areas through regulatory measures, creation of new non-farm employment opportunities and strengthening of traditional institutions through providing extension services for local communities and facilitating NGO involvement so as to minimize the adverse effects on forest resources. 相似文献
49.
为了查明新疆乌鲁木齐县石人沟地区的地衣物种多样性及其区系和群落特征,在石人沟地区的不同植被带设立16个样点,对地衣进行了样方调查、标本采集和标本鉴定,并对地衣区系成分和生长型进行了分析。结果表明,石人沟地区地衣共有30种,隶属于17属,10科,5目,其中叶状地衣和壳状地衣种类较丰富。地衣区系成分划分为世界广布成分、环北极成分、温带成分、中亚物种和中国特有物种等5个区系成分;按照该地区地衣生长的现状,把其划分为岩面生、树生、藓丛生和地面生等4个类型;该地区地衣的生长型主要以壳状地衣为主,其次为叶状地衣,缺乏枝状地衣种类。同时基于30种地衣及盖度数据,应用双向指示种分析方法(TWINSPAN)和除趋势对应分析(DCA)将该地区的地衣划分为3个样点组,并计算了物种多样性和均匀度指数。 相似文献
50.
Azhar Abbas Muhammad Yaseen Muhammad Khalid Muhammad Naveed Muhammad Zahir Aziz Yasir Hamid 《Journal of plant nutrition》2017,40(16):2303-2311
A field experiment was conducted to evaluate effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat under field condition. Experiment plan was comprised of twelve treatments with four replications including treatments without application of urea and biochar (control) and urea only. Biochar was applied at 1–10% of the weight of urea fertilizer applied each treatment. Results showed that application of biochar at 10% with recommended dose of urea significantly improved plant height, spike length, number of tillers, number of spikelet per spike, 1000 grain weight, grain yields, biomass yield, harvesting index, nitrogen (N) concentration and uptake in grain and straw, and agronomic efficiency of nitrogen by 6.0%, 11.1%, 32.0%, 55.3%, 5.4%, 38.0%, 19.0%, 9.0%, 19.0%, 26.0%, 65.0%, 50.0%, and 63.0%, respectively, as compared to treatment comprised of recommended rate of nitrogen without biochar. 相似文献