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81.
Anaesthetic efficacy of eugenol was investigated on iridescent shark, Pangasius hypophthalmus. Fish (2, 5, 10 and 20 g) subjected to 20–200 mg L?1 eugenol and behavioural response as well as induction and recovery times were recorded. Induction and recovery times were significantly affected by eugenol concentration as well as fish weight (< 0.05). Generally, 27–300 s after exposure to 20–200 mg L?1 eugenol, iridescent sharks reached stage 3 anaesthesia (suitable for general handling). Fish entered stage 4 anaesthesia (suitable for surgery and blood sampling) over 54–710 s exposure to such concentrations. Recovery time was 109–600 s in all weight classes as well as eugenol concentrations. Mortality (44–100%) was only observed in 2 g fish when subjected to 110–170 mg L?1 eugenol. This study, for the first time, showed behavioural response of iridescent shark to anaesthesia as well as effectiveness of eugenol as anaesthetic in this important aquaculture‐ornamental species. According to the models obtained in this study, minimum eugenol concentrations to induce anaesthesia over less than 3 min were 53.8–81.5 mg L?1 in 2–20 g fish. Likewise, maximum eugenol concentrations in which fish recovered over less than 5 min were 65.9–105.8 mg L?1 in 2–20 g fish.  相似文献   
82.
Increasing the amount of nutrients in plant-based foods will help to improve the nutritional status of people in the World. Faba bean (Vicia faba L.) as a staple food in developing countries has the potential to provide many nutrients in human diets. The objective of this study was to characterize the nutrient concentrations in leaf, pod, and seed of faba bean varieties. A field study was conducted with six faba bean varieties. Variation in the elemental concentrations of nutrients and protein occurred among varieties and different parts of the plants. The highest concentrations of nitrogen, phosphorus, potassium, zinc, or copper and protein were in the seeds. However, the highest accumulation of calcium, magnesium, iron, or manganese was in the leaves. We recommend that faba bean can be considered as a valuable crop in the diet of nutrient-deficient consumers due to high concentration nutrients in edible parts of the plant.  相似文献   
83.
Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon’s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei’s genetic distance and genetic identity between populations revealed a close association between geographically isolated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among-population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species.  相似文献   
84.
A two-year experiment was conducted in an iron(Fe)-deficient orchard with calcareous soil to find out an alternate method for soil application of Fe ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid) (Fe-EDDHA) in orange trees. Foliar sprays of Fe-EDDHA (5 g l?1, pH = 7.8), sulfuric acid (pH = 3), citric acid (5 g l?1, pH = 2.4), Fe (II) sulfate solutions (250, 500, and 750 mg Fe l?1) with their initial pH (6.5, 6.35, and 6.12) and reduced ones to pH of 3 were compared with soil applied (75 g tree?1) Fe-EDDHA and a control test. Although optimum chlorophyll content, leaf Fe concentration, fruit quantitative and qualitative attributes were resulted from soil application of Fe-EDDHA, repeated sprays of Fe-EDDHA or acidified Fe solutions created suitable results. Acidification of Fe solutions made them more effective in alleviation of leaf Fe concentration and Fe chlorosis, probably due to remobilization of inactive Fe within the plant and prevention of Fe oxidation and precipitation in foliar solutions.  相似文献   
85.

Objective

To determine the effect of fentanyl on the induction dose of propofol and minimum infusion rate required to prevent movement in response to noxious stimulation (MIRNM) in dogs.

Study design

Crossover experimental design.

Animals

Six healthy, adult intact male Beagle dogs, mean ± standard deviation 12.6 ± 0.4 kg.

Methods

Dogs were administered 0.9% saline (treatment P), fentanyl (5 μg kg?1) (treatment PLDF) or fentanyl (10 μg kg?1) (treatment PHDF) intravenously over 5 minutes. Five minutes later, anesthesia was induced with propofol (2 mg kg?1, followed by 1 mg kg?1 every 15 seconds to achieve intubation) and maintained for 90 minutes by constant rate infusions (CRIs) of propofol alone or with fentanyl: P, propofol (0.5 mg kg?1 minute?1); PLDF, propofol (0.35 mg kg?1 minute?1) and fentanyl (0.1 μg kg?1 minute?1); PHDF, propofol (0.3 mg kg?1 minute?1) and fentanyl (0.2 μg kg?1 minute?1). Propofol CRI was increased or decreased based on the response to stimulation (50 V, 50 Hz, 10 mA), with 20 minutes between adjustments. Data were analyzed using a mixed-model anova and presented as mean ± standard error.

Results

ropofol induction doses were 6.16 ± 0.31, 3.67 ± 0.21 and 3.33 ± 0.42 mg kg?1 for P, PLDF and PHDF, respectively. Doses for PLDF and PHDF were significantly decreased from P (p < 0.05) but not different between treatments. Propofol MIRNM was 0.60 ± 0.04, 0.29 ± 0.02 and 0.22 ± 0.02 mg kg?1 minute?1 for P, PLDF and PHDF, respectively. MIRNM in PLDF and PHDF was significantly decreased from P. MIRNM in PLDF and PHDF were not different, but their respective percent decreases of 51 ± 3 and 63 ± 2% differed (p = 0.035).

Conclusions and clinical relevance

Fentanyl, at the doses studied, caused statistically significant and clinically important decreases in the propofol induction dose and MIRNM.  相似文献   
86.
To investigate the effect of applying 15N-labeled ammonium sulfate with or without a nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on fertilizer use efficiency and crop productivity of different wheat genotypes, a field trial was conducted at the Nuclear Agricultural Department’s farm of Iran in 2013–2014. The treatments included five wheat genotypes with different 13 C isotope discrimination and three fertilizer treatments, an unfertilized control, 15N-labeled ammonium sulfate, and 15N-labeled ammonium sulfate with DMPP in three replications. Soil samples were taken after 2, 4, and 6 weeks after sowing and also at harvest time. Results from 15N experiment showed that DMPP delayed nitrification of ammonium for 42 days. Genotypes with lower discrimination index had greater uptake of ammonium ions which led to increase crop yield and nitrogen fertilizer use efficiency. The results also suggested that the use of DMPP may not be beneficial in some fast growing wheat genotypes.  相似文献   
87.
The aim of the present study was to determine the analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs. Two hundred ninety E. coli isolates were recovered from 300 rectal swabs of diarrheic lambs and were confirmed by biochemical tests. The pathotype determination was done according to the presence of genes including f5, f41, LTI, STI, bfp, ipaH, stx 1 , stx 2 , eae, ehlyA, cnf 1 , cnf 2 , cdIII, cdIV, and f17 by PCR method. Sixty-six isolates (23.72%) possessed the STI gene and categorized into entrotoxigenic E. coli (ETEC). Nine isolates (3.1%) and five isolates (1.72%) were positive for the cnf1 and cnf2 genes which categorized into necrotoxic E. coli (NTEC). Hundred and seventeen isolates (40.34%) harbored stx 1 and/or stx 2 and classified as Shiga toxin-producing E. coli (STEC). Thirteen isolates (4.48%) were assigned to atypical entropathogenic E. coli (aEPEC) and possessed eae gene. Two isolates (0.68%) were positive for ipaH gene and were assigned to entroinvasive E. coli (EIEC). Statistical analysis showed a specific association between eae gene and STEC pathotype (P?<?0.0001). The most prevalent resistance was observed against lincomycin (96.5%) and the lowest resistance was against kanamycine (56.02%), respectively. The high prevalence of STEC and ETEC indicates that diarrheic lambs represent an important reservoir for humans. ETEC may play an important role for frequent occurrence of diarrhea in lambs observed in this region. Due to high antibiotic resistance, appropriate control should be implemented in veterinary medicine to curb the development of novel resistant isolates.  相似文献   
88.
89.
Mango (Mangifera indica L.) and their components are commonly used in folk medicine for many curative effects. The protective effects of different concentrations of aqueous extract of Mangifera indica L. fruit (Mango Extract) (20, 50 and 100 μg/ml) and also gallic acid (100 μM) as a pure compound in the extract were examined against oxidative stress toxicity induced by cumene hydroperoxide (CHP) in isolated rat hepatocytes. The extracts and gallic acid (100 μM) protected the hepatocyte against all oxidative stress markers including cell lysis, ROS generation, lipid peroxidation, glutathione depletion, mitochondrial membrane potential decrease, lysosomal membrane oxidative damage and cellular proteolysis. Mango Extracts (20, 50 and 100 μg/ml) were more effective than gallic acid (100 μM) in protecting hepatocytes against CHP induced lipid peroxidation. On the other hand gallic acid (100 μM) acted more effective than Mango Extracts (20, 50 and 100 μg/ml) at preventing lysosomal membrane damage. In addition H2O2 scavenging effect of all extracts were determined in hepatocytes and compared with gallic acid (100 μM). There were no significance differences (P<0.05) between all plant extracts and gallic acid (100 μM) in H2O2 scavenging activity. These results suggest a hepatoprotective role for Mango Extract against liver injury associated with oxidative stress.  相似文献   
90.
An evaluation of genetic diversity in 39 wild asparagus populations was carried out using morphological and RAPD markers. A combination of morphological traits and random RAPD primers was used to examine the level of genetic variation and polymorphisms among the populations. A factor analysis using Ward's method on mean values of morphological characteristics indicated seven main factors resulting in four groups. Analysis of polymorphic bands using Jaccard's similarity coefficient indicated that genetic similarity ranged between 0.71 and 0.29. At a similarity level of 0.64, the populations were divided in three sub-clusters, containing 34, four and one populations, respectively. Significant regression associations were found between 21 morphological characteristics and 18 RAPD markers, revealing some informative markers associated with some traits. The highest R2 was related to 18 RAPD markers associated with gender (53.5%) that among them BA-042000 had a maximum R2. The results showed that Iranian wild asparagus with its high levels of genetic variation could be considered as a valuable gene pool for future asparagus breeding programs. Furthermore, it could be inferred that morphological characteristics and RAPD markers are suitable tools to discriminate asparagus populations for the evaluation of genetic diversity.  相似文献   
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