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61.
The first evidence of proliferative kidney disease (PKD) in an Austrian river (the River Kamp) was documented in 2016, and no information on the PKD infection status of trout in other rivers was available. Since then, brown trout (Salmo trutta fario) and rainbow trout (Oncorhynchus mykiss) have been collected from rivers in Upper and Lower Austria for different diagnostic purposes. In this study, we summarize the recent findings of a first survey concerning the distribution of Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), from these samples. Between September 2015 and October 2017, a total of 280 brown trout and 39 rainbow trout were collected from 21 rivers in the provinces of Upper and Lower Austria. T. bryosalmonae was detected by PCR of kidney tissue in 17 of 21 sampled rivers and in 138 of 280 brown trout as well as in 11 of 39 rainbow trout. Pathological signs of PKD (e.g., hypertrophy of the kidney) were observed in 33 analysed brown trout and six rainbow trout samples. No correlations between fish infected by Tbryosalmonae and the parameters size and age class, condition factor, geological origin of the streams and distribution within the river course were found, while positively tested fish are significantly increased at sampling sites exceeding water temperatures of 15°C for median periods of 115 days. The prevalence within the affected streams or stream sections is highly variable, and in single rivers, infection rates of up to 90% are confirmed.  相似文献   
62.
Agricultural sector is a major source of employment and export earnings for Pakistan. Exports of Pakistan are highly concentrated in agricultural products including cotton, rice, sugar and fruit. This study analyzed comparative and competitive advantages of the main agricultural products of Pakistan, i.e. cotton, rice and tangerines. Consumption patterns of top exporting countries in each category were also analyzed. Results revealed that Pakistan had strong competitiveness for export of these commodities. Strong potential for growth in the agricultural sector of Pakistan was found and it could be optimized to raise export earnings and meet the objectives of the strategic trade policy framework(STPF) 2015-2018 of Pakistan.  相似文献   
63.
64.
Polypropylene fabrics were coated with copper particles using electroless plating, screen printing and wire arc spray coating techniques. Surface morphology of the fabrics was studied using optical and scanning electron microscopes (SEM). Furthermore, tensile strength, electrical conductivity, thermal conductivity, air permeability, water contact angle and fog collection efficiency of the coated fabrics were measured and the obtained results were analyzed. SEM micrographs showed that a very thin and uniform layer of copper deposited on the surface of the electroless plated polypropylene fibers. In the printed or spray coated fabrics the copper particles filled the spaces between yarns and fibers. The polypropylene electroless copper plated fabrics showed higher tensile strength, electrical conductivity, air permeability and thermal conductivity when compared with the fabrics coated with copper screen printed and copper spray coated fabrics. Finally, the obtained results showed that copper electroless plating could increase the fog collection efficiency of polypropylene fabrics considerably. As a conclusion, the surface modified copper electroless polypropylene fabrics are good candidates for fog collection in appropriate regions which need further investigations.  相似文献   
65.
Late blight (LB), caused by Phytophthora infestans, is one of the most devastating diseases of tomato (Solanum lycopersicum) worldwide. Due to the emergence of new and aggressive P. infestans isolates, identifying new genetic resistance to LB is a priority in tomato breeding. Recently, we reported the identification of several Solanum pimpinellifolium accessions with strong LB resistance. In this study, we investigated the utility of resistant accession PI 163245 for tomato breeding by examining heritability (h2) of resistance and the response to selection for resistance. Estimates of h2 based on F2 : F3 and F3 : F4 parent : offspring correlation analyses averaged 0.79 and 0.94, respectively, suggesting the heritable nature of LB resistance in PI 163245. Analysis of response to selection for resistance from F2 to F4 generations indicated a realized h2 of 0.63, confirming the utility of this resistance in tomato breeding. Two methods of estimating the minimum number of loci involved indicated the presence of one major resistance locus. Currently, genetic mapping and breeding efforts are underway to further confirm the viability of this accession for improving tomato LB resistance.  相似文献   
66.
A 3-year-old crossbreed male dog was presented with a history of blunt facial trauma. Skull radiographs showed right zygomatic arch fracture. An electrocardiogram revealed bradycardia, first-degree atrioventricular block and QT prolongation. Standard biochemical profile including electrolytes was normal. Atropine response test (0.04 mg/kg intravenously) restored normal sinus rhythm at a rate of 140 bpm with normal QT and PR intervals. This observation is consistent with oculocardiac reflex secondary to zygomatic arch fracture.  相似文献   
67.
One of the most common strategies in the treatment of cognitive disorders is enhancing the acetylcholine level in the brain through the inhibition of acetylcholinesterase. Despite the effectiveness of current modern drugs, more attention has been paid for finding new anticholinesterase agents from medicinal plants. Zatraia multiflora Boiss. is an endemic plant to Iran which has different uses in traditional medicine as anti-inflammatory, antimicrobial, anti spasmodic. We intended to evaluate the in vitro anticholinesterase and free radical scavenging activity of the essential oil and methanolic extract of Z. multiflora. The essential oil and methanolic extract of the plant were evaluated for anticholinesterase activity using modified Ellman method. The free radical scavenging effect of the samples were studied by using of the diphenylpicrylhydrazyl (DPPH). IC50 and the percent of inhibition of acetylcholinesterase was calculated from regression equation. The results showed that both the essential oil and methanolic extract of the plant exhibited high anticholinesterase activity (95.3 +/- 3.4 and 87.9 +/- 2.2% inhibition, respectively) which was similar to eserine (96.2 +/- 1.7% inhibition). The IC50 value of essential oil was determined as 0.97 +/- 0.12 microg mL(-1) in comparison to eserine (0.13 +/- 0.02 microg mL(-1)). The results of antioxidant assay showed that both the essential oil and methanolic extract potentially inhibit DPPH free radical (94.8 +/- 2.4 and 93.2 +/- 1.7% inhibition, respectively). The essential oil and methanolic extract of Z. multiflora have beneficial effect in health promotion and this plant would be good candidate for further studies.  相似文献   
68.
A new collection of several Red Sea sponges was investigated for the discovery of potential breast cancer migration inhibitors. Extracts of the Verongid sponges Pseudoceratina arabica and Suberea mollis were selected. Bioassay-directed fractionation of both sponges, using the wound-healing assay, resulted into the isolation of several new and known brominated alkaloids. Active fractions of the sponge Pseudoceratina arabica afforded five new alkaloids, ceratinines A–E (2–6), together with the known alkaloids moloka’iamine (1), hydroxymoloka’iamine (7) and moloka’iakitamide (8). The active fraction of the sponge Suberea mollis afforded the three known alkaloids subereamolline A (9), aerothionin (10) and homoaerothionin (11). Ceratinine B (3) possesses an unprecedented 5,7-dibrominated dihydroindole moiety with an epoxy ring on the side chain of a fully substituted aromatic moiety. Ceratinines D (5) and E (6) possess a terminal formamide moiety at the ethylamine side chain. Subereamolline A (9) potently inhibited the migration and invasion of the highly metastatic human breast cancer cells MDA-MB-231 at the nanomolar doses. Subereamolline A and related brominated alkaloids are novel scaffolds appropriate for further future use for the control of metastatic breast cancer.  相似文献   
69.
Lactococcosis, a significant emerging disease of fish caused by Lactococcus garvieae, has become one of the devastating problems due to its serious economic damage in aquaculture. The aim of this study was to isolate and characterize a lytic phage infecting L. garvieae as a potential bioagent for the treatment of lactococcosis. In this regard, one strain of L. garvieae was isolated from diseased rainbow trout, and then, following biochemical and molecular identifications, its specific phage, WWP-1, which was able to destroy L. garvieae cells through the lytic cycle, was isolated from a municipal wastewater sample. Transmission electron microscope revealed that the isolated phage possesses an icosahedral head and a non-contractile short tail, resembled to members of the family Podoviridae. Moreover, phage WWP-1 represented optimal antibacterial activity at temperatures ranging from 15 to 30 °C, suggesting that it could be very effective at rainbow trout rearing temperature. Restriction profile analysis revealed that NdeI can digest WWP-1 genome while EcoRI, EcoRV, and BamHI were incapable of cutting its DNA. According to the in vivo experiment result, WWP-1 could decrease mortality rate of infected rainbow trout in aquaculture. The results suggest that this naturally occurring bacteriophage could be considered as a promising agent to control the disease caused by L. garvieae strains in rainbow trout rearing.  相似文献   
70.
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   
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