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21.
This study describes length–weight (LWR) and length–length relationships (LLR) of bluefin tuna (BFT), Thunnus thynnus, in the eastern Mediterranean (Levantine Sea). Fulton’s condition factor (K) was also calculated for each standard length class for both sexes. A total of 363 specimens, 175 males and 188 females, were caught by purse‐seine from late winter to early summer 2003 off Antalya Bay, Turkey. Fork length values of 175 BFT males were between 114 and 250 cm with an average of 159.3 cm ± 2.14, and between 116 and 256 cm with an average of 163 cm ± 2.26 in 188 females. LWRs indicated positive allometric growth in both males and females. The coefficient b ranged from a minimum 3.32 for males to a maximum of 3.35 for females. Results indicated that the LLRs were highly correlated (r2 > 0.99, P < 0.001). K values ranged from 1.45 to 2.11 (mean: 1.56 ± 0.12) in males and from 1.43 to 2.14 (mean: 1.69 ± 0.06) in females.  相似文献   
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Sampling was carried out on a seasonal basis during 2007–2009, using a conventional bottom trawl net with 44 mm codend mesh size in Izmir Bay, Aegean Sea. A total of 116 valid hauls: 27 in autumn, 28 in winter, 35 in spring and 26 in summer, were conducted at depths ranging from 30 to 70 m. A total of 112 species: 15 Chondrichthyes, 83 Osteichthyes, 11 Cephalopoda and 3 Crustacea were obtained in the trawl codend. All captures were separated into commercial (C) and non‐commercial (NC) species. The C ratio was 69.6%, while NC (i.e. discards) was 30.4%. Diplodus annularis was the most abundant species in all seasons, followed by Mullus barbatus, Merluccius merluccius, Citharus linguatula, Serranus hepatus, Lepidotrigla cavillone, Spicara maena, Myliobatis aquila, Diplodus vulgaris, and Trisopterus minutus in decreasing order of abundance. These top ten species constituted 75% of total catch weight. Biomass ratios of total discards to commercial species were 0.44 : 1.  相似文献   
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Lactococcus lactis has two essential ribonucleotide reductases for DNA biosynthesis and repair which are affected in the presence or absence of oxygen. Expression of glutaredoxin like protein (NrdH), the hydrogen donor for ribonucleotide reductase, was found to be regulated by the FNR like proteins (FlpA and FlpB). Proteomics study demonstrated that expression level of NrdH significantly decreased in the flpA and flpAB deletion mutants. The nrdH gene is located in an nrdHIEF operon and encoding the NrdEF ribonucleotide reductase, which is active under aerobic and anaerobic conditions. Regulation of expression of the nrdHIEF operons was investigated using beta-galactosidase as a reporter gene. The 588 bp fragment containing the nrdH promoter and gene cloned into the pORI vector immediately upstream of a promoterless lacZ gene. Constructed plasmid was transferred into wild type (MG1363), single mutant (flpA orflpB) and double mutant (flpAB). Aerobically, nrdH promoter activity is 15-fold higher than anaerobic expression.  相似文献   
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Reactive oxygen and nitrogen species have been implicated in the pathogenesis of bleomycin-induced lung fibrosis. The effects of aminoguanidine and erdosteine on the bleomycin-induced lung fibrosis were evaluated in rats. The animals were placed into five groups: Vehicle + vehicle, vehicle + bleomycin (2.5 U/kg), bleomycin + aminoguanidine (200 mg/kg), bleomycin + erdosteine (10 mg/kg), and bleomycin + erdosteine + aminoguanidine. Bleomycin administration resulted in prominent lung fibrosis as measured by lung hydroxyproline content and lung histology, which is completely prevented by erdosteine and aminoguanidine. A strong staining for nitro tyrosine antibody in lung tissue and increased levels of lung NO were found in bleomycin group, that were significantly reduced by aminoguanidine and erdosteine. Aminoguanidine and erdosteine significantly prevented depletion of superoxide dismutase and glutathione peroxidase and elevated myeloperoxidase activities, malondialdehyde level in lung tissue produced by bleomycin. Data presented here indicate that aminoguanidine and erdosteine prevented bleomycin-induced lung fibrosis and that nitric oxide mediated tyrosine nitration of proteins plays a significant role in the pathogenesis of bleomycin-induced lung fibrosis. Also our data suggest that antifibrotic affect of antioxidants may be due to their inhibitory effect on nitric oxide generation in this model.  相似文献   
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Antiepileptic drugs could cause changes in the trace element status of the body. Valproic acid (VPA) is a very effective anticonvulsant agent widely used in the management of various forms of epilepsy. Nail trace element content is a reliable index of trace element nutritional status of the body. To determine whether some of the side effects of antiepileptic drugs could be the result of zinc (Zn) depletion within tissues, Zn concentrations as well as copper (Cu) concentrations in nail and serum in 59 children having various types of epilepsy receiving valproate and 31 controls were assessed. Although serum Zn level in epileptic patients was found to be decreased, there was no difference in nail samples when compared to controls. There was a statistically significant increase in nail Cu level in epileptic patients when compared to controls. On the other hand, serum Cu levels were not different between the groups. Although none of our patients showed any symptoms of Cu elevation and Zn depletion, we should pay attention to potential body trace element changes in patients with epilepsy under VPA treatment. In conclusion, our results indicate that serum trace metal homeostasis might be affected by VPA therapy, but not by the convulsive disorder itself.  相似文献   
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The aim of this study was to evaluate the protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage in rats. Hepatic malondialdehyde, glutathione and hydroxyproline levels and histopathologic alterations in liver specimens were assessed. 200 mg/kg/day Ginkgo biloba extract were given orally to the animals for 10 days, then a single dose of 2 ml/kg b.w. carbon tetrachloride was, administered intraperitoneally. Ginkgo biloba extract treatment reduced hepatic malondialdehyde levels significantly (p < 0.05), but did not alter glutathione (p > 0.05) and hydroxyproline levels (p > 0.05). The light and electron microscopic findings showed that Ginkgo biloba extract limited the CCl4-induced hepatocyte necrosis and atrophy. These results suggest that this extract may protect the hepatocytes from carbon tetrachloride-induced liver injury.  相似文献   
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Activities of adenosine deaminase (ADA), 5′ nucleotidase (5′NT), xanthine oxidase (XO), guanase (GUA), total superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes were measured in cancerous brain tissues from 48 patients. The results were compared with those of the control brain tissues from 17 subjects. Important differences were found between enzyme activities of control brain tissues and those of tumoral tissues.

There were important intracorrelations between some of the enzyme activities in both neoplastic and control brain tissues. The correlations exhibited significant differences between control group and patient groups, indicating disordered enzymatic relations in the cancerous brain tissues.

The results suggest that enzymatic make-up relating to free radical and purine metabolism shows great differences between cancerous and non-cancerous brain tissues. Similar diversity is also present between various types of cancerous brain tissues. This implies that enzymatic make-up of the tissues also depends on the cancer type. We thus suggest that the results obtained from this kind of experimental studies should be evaluated individually for the tissue analyzed taking the cancer type into consideration without making general evaluations.  相似文献   
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