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1.
Farmed gilthead sea bream, Sparus aurata, frequently escape from the sea cages and interact with wild populations. The impact of these interactions on the wild populations will depend, in part, on differences in performance of the bream. This study compared the swimming performance of the wild and farmed fish in a current channel. The absolute critical swimming speed (Ucrit) increased with increasing size while the relative Ucrit decreased. Even at the same length there were noticeable performance differences between the individuals. The wild sea bream have significantly higher (P<0.05) absolute Ucrit performance (0.86±0.01 m s−1) than the farmed fish (0.79±0.01 m s−1) and significantly higher (P<0.05) relative Ucrit performance (4.52±0.05 BL s−1) than the farmed fish (4.21±0.05 BL s−1). The present study suggests that cultured sea bream may not have the ability to compete with wild sea bream in native seawaters.  相似文献   
2.
The aim of the present study was to investigate abortion storms that occurred in the Marmara region of Turkey in 2008-2009 using a real-time PCR. Two aborted foetuses were necropsied and histo-pathological findings reported herein. Ten lungs, 3 brains and one nasal swab from 10 aborted foetuses, 6 nasal swabs and 3 vaginal swabs from aborting mares were included in this study. EHV-1 was isolated from the lung, liver and brain of 1 aborted foetus. EHV-1 DNA was detected in the lungs, livers and spleens of 2 necropsied foetuses and in 3 lungs from 10 foetuses submitted for diagnosis. A brain from one of the aborted foetuses was also positive for EHV-1 DNA. EHV-4 DNA was detected only in a nasal swab of one of the tested foetuses. Neither EHV-1 nor EHV-4 DNA was detected in the swabs of aborting mares. Sequence analysis of the glycoprotein B of the strains was performed and a phylogenetic tree was generated. The results indicated that 4 of the 5 Turkish EHV-1 strains (TR02, TR03, TR04 and TR05) clustered together; the fifth strain (TR01) was slightly removed from the group and clustered with other EHV-1 from various origins. Single nucleotide polyporphism (SNP in ORF30) associated with neuropathogenesis was not detected in any of the strains. At necropsy, sub-milier focal necrosis in the liver and spleen was observed. Microscopically, focal coagulation necrosis and marked eosinophilic intranuclear and intracytoplasmic inclusion bodies in the hepatocytes localised around the necrotic areas in the liver. Severe coagulation necrosis in white pulp of the spleen was also observed.  相似文献   
3.
There has been an increase in outbreaks of neuropathogenic equine herpesvirus-1 (EHV-1) in the United States and Europe. However, the presence and frequency of neuropathogenic EHV-1 in Turkish horses are not known at present. This study aimed to investigate the frequency of EHV-1 and neuropathogenic strains of EHV-1 in the Marmara Region of Turkey. Samples were analyzed for the presence of EHV-1 and neuropathogenic EHV-1 by real-time PCR TaqMan probe assays. Overall detection rate of EHV-1 was 45.5% (51 of 112). The detection rates were 70.5% (24 of 34) in aborted fetuses, 53.3% (8 of 15) in neonatal deads, 66.6% (4 of 6) in foals, 40% (2 of 5) in dead mares, and 25% (13 of 52) in living mares. Overall detection rate of neuropathogenic EHV-1 was 7.8% (4 of 51), and the real-time PCR results were confirmed by sequencing. Neuropathogenic strains of EHV-1 were detected in the brain and lung of two mares with neurological disease but without a history of abortion, in the brain of a foal that died of respiratory disorder, and in the nasal swab from a mare with a history of abortion. On histopathology, nonpurulent meningoencephalitis, hemorrhages, and vasculitis were seen in the brain. In conclusion, results of this study indicated, for the first time, that the neuropathogenic EHV-1 is circulating in the Marmara Region of Turkey. The results of this study also show that the current risk for non-neuropathogenic strains is high, whereas risk for the neuropathogenic EHV-1-G2254 strain seems to be low. As outbreaks of EHV-1 continue in the Marmara region of Turkey, surveillance for neuropathogenic EHV-1 genotype should be maintained.  相似文献   
4.
From the MeOH extract of Sideritis trojana, a new iridoid glycoside, 10-O-(E)-feruloylmelittoside (1) was obtained in addition to four known iridoid glycosides [melittoside (2), 10-O-(E)-p-coumaroylmelittoside (3), stachysosides E (4) and G (5)]. Moreover, five phenylethanoid glycosides [verbascoside (6), isoacteoside (7), lamalboside (8), leonoside A (9), isolavandulifolioside (10), three flavone glycosides (isoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (11), 4'-O-methyisoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (12), 3'-hydroxy-4'-O-methyisoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (13) and a benzylalcohol derivative (di-O-methylcrenatin) were obtained and identified. The structures were elucidated on the basis of NMR and HRMS data. All compounds were tested for their antioxidant activity by in vitro TEAC assay and some of them exhibited moderate activity (0.97-1.44 mM) when compared with the reference compound (quercetin 1.86 mM). Glycosides 6-13, the most active compounds in the TEAC assay, were also tested by flow cytometry to evaluate their ability to affect the levels of reactive oxygen species (ROS) in human prostate cancer cells (PC3).  相似文献   
5.
Common ragweed invasion poses serious risks to human health, biodiversity and agricultural production throughout the world. Although ragweed has an enormous potential to expand its range in Turkey, studies on ragweed have only concentrated on the Black Sea region. An exploratory survey was conducted to observe the level of ragweed occurrence on the nodes of predecided 10 × 10 km grids in the Thrace region of Turkey. Ragweed populations were observed in 44 out of 129 sites in a wide range of habitats, including roadsides, pastures, agricultural fields and non‐agricultural areas. The highest levels of ragweed infestation were recorded in the agricultural fields, followed by the roadsides. The most‐invaded crop was sunflower. The sunflower fields had the highest ragweed coverage as well and invasion even resulted in crop failure alongside the field borders. A spatial analysis of the data indicated that ragweed exhibited an aggregated pattern over the Thrace region. Ragweed distribution was not associated with the characteristics of the soils, which had a varying range of pH, electrical conductivity and texture. The results revealed that ragweed invasion can arise as a serious weed problem, interfering with the sustainability of sunflower production in Thrace and other sunflower‐producing regions of the country. A high degree of ragweed infestation also will contribute to the pollen level counts for the most crowded cities in the region, posing a serious danger to human health.  相似文献   
6.
This study was performed to describe a practical technique for ultrasound examination of the scrotal content of the rabbit. The scrotal content of normal rabbits and those with induced lesions (i.e. needle biopsy of the testis and epididymal ligation) were viewed using a portable scanner connected to a 5 or 7.5 MHz real time, B-mode linear array transducer. The effect of frequency (5 and 7.5 MHz), pad material placed under the testicle (rubber, plastic and carton) and the presence of a water sack between the probe and organ were examined to optimize the technique. The best image quality was obtained using a 5-MHz probe when the testicle was fixed on a rubber pad and covered by a water sack. Testicular parenchyma was imaged as homogeneous and moderately echoic. Caput and cauda epididymis were identified as homogeneous and less echoic compared with the testis parenchyma. Variations in the testicular echotexture that occur secondarily to epididymal ligation and testis biopsy could be screened readily. In conclusion, real-time ultrasonography, performed as described in this study, may provide a valuable tool to screen scrotal contents and to identify certain pathological conditions that affect fertility in the rabbit.  相似文献   
7.
The acaricidal effects of the volatile essential oil Origanum minutiflorum O. Schwarz & P.H. Davis (Lamiaceae) against adult Rhipicephalus turanicus was evaluated at a variety of concentrations and exposure times. Generally tick mortality increased with concentration and exposure. Ticks exposed to vapors from cotton wicks containing at least 10 μl/L resulted in complete (100%) mortality at 120 min. The major constituent of essential oil obtained from the plant material of O. minutiflorum was carvacrol.  相似文献   
8.
Synthetic fibers are generally produced with circular cross sectional shapes. Other cross sectional shaped fibers such as trilobal, triangular, hollow and pentagonal fibers are also produced to improve some properties of fibers and fabrics such as lustre, handle, wicking rate, strength, stiffness and bulkiness. In this research we aimed to investigate compressional behaviours of fabrics knitted from polypropylene fibers having three different cross sectional shapes; namely circular, trilobal and triangular. Morphological, structural and mechanical properties of produced fibers were evaluated by using scanning electron microscopy, X-ray diffractometry, differential scanning calorimetry and tensile tester, respectively. In terms of structural and mechanical properties, no significant differences were found related to fiber cross sectional shapes. Then, plain knitted farbrics were produced and compressional properties of these fabrics were investigated. Fabrics knitted from trilobal fibers showed the highest compressibility properties and it is followed by fabrics which are produced from triangular and circular fibers.  相似文献   
9.
10.
Iron (Fe)-deficiency chlorosis causes considerable yield losses in chickpea (Cicer arietinum L.) when susceptible genotypes are grown in calcareous soils with high pH. The most feasible method for alleviating Fe deficiency is the selection of suitable cultivars resistant to Fe deficiency chlorosis. ICC 6119 (desi type), which is Fe-deficient chlorosis, was crossed with CA 2969 and Sierra (kabuli types), resistant to Fe deficiency chlorosis. Inheritance of resistance to Fe deficiency in chickpea revealed that the resistance was controlled by a single dominant gene in these genotypes crossed. A negative selection for resistance to Fe deficiency chlorosis will be effective after segregating generations.  相似文献   
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