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991.
There is increasing evidence of a biochemical link between oxidative stress and bone metabolism. Oxidative stress has been shown to be involved in bone resorption as it causes loss of bone mineral density (BMD). Paraoxonase 1 (PON1), can prevent these effects of the oxidative stress on bone formation. It has been suggested that the PON1 gene as possibly implicated in reduced BMD in bone fragility cases. It has been hypothesized that PON1 gene polymorphisms may influence both the risk of osteoporosis and osteopenia occurrence and prognosis. The aim of our study is to evaluate the relationship between PON1 polymorphisms and bone fragility development. Seventy-four osteoporotic, 121 osteopenic and 79 nonosteoporotic postmenopausal women were recruited. For detection of the polymorphisms, polymerase chain reaction-restriction fragment length polymorphism techniques have been used. BMD was measured at the lumbar spine and hip by dual-energy X-ray absorptiometry. Distributions of PON1 (PON 192 and PON 55) polymorphisms in study groups were not significantly different. But, there was medium strength connection between in the osteopenic with control groups regarding PON1 55–PON1 192 haplotypes and we found a power strength connection between in the osteoporosis with control groups regarding PON1 55–PON1 192 haplotypes. Furthermore, subjects with PON1 192RR and PON1 55LL genotypes had lower PON activity values of osteoporotic subject compared to healthy control and this difference was statistically significant (p < 0.05). This result suggest that PON1 genotypes could be higher risk for osteoporosis, as determined by reduced BMD.  相似文献   
992.
With the aim of understanding virus movement and fluctuations in the virus concentration in bulb and leaves of onion (Allium cepa L.) plants after infection, Onion yellow dwarf virus (OYDV) was analysed by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). OYDV concentrations were higher in onion leaves of plants grown from tested bulbs compared with bulbs, although the virus was successfully detected in bulb of onion.  相似文献   
993.
The effect of B toxicity on antioxidant responses of soybean (Glycine max) cv. Athow was investigated by growing plants for 43 days at 0.2 (control), 2 and 12 mg B kg?1. At the end of the treatment period, shoot growth, lipid peroxidation level, the activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), and their isoenzymes in leaves were measured. Boron concentration in leaves was significantly increased by the increasing levels of B treatment from 43 to 522 mg kg?1, and shoot dry matter was depressed at 12 mg B kg?1. Significant increases in SOD, CAT, and APX activities were determined in leaves under 12 mg B kg?1; however, GR activities were decreased while POX activity was unchanged. Increased enzymic antioxidant activity arose from a combination of newly formed isoenzymes and activation of existing isoenzymes. By contrast, SOD and GR activities were decreased by 2 mg B kg?1 concentration as compared to the control groups while POX activity was increased and the activity of CAT did not change. Malondialdehyde content increased under 2 mg B kg?1 but decreased under 12 mg B kg?1. These results suggest that higher antioxidant activity observed under 12 than at 2 mg B kg?1 provided higher free radical-scavenging capacity, and thus a lower level of lipid peroxidation in Athow. While the induction of increased antioxidant activity was related to internal boron levels, the signaling and coordination of responses remain unclear.  相似文献   
994.
995.
Abstract

The distribution of the Hardun, Agama stellio, the Caucasian Agama, Agama caucasia, the Syrian Agama, Agama ruderata, and Phrynocephalus helioscopus, in Turkey is presented with dot maps A. stellio and A. caucasia are sharply separated both horizontally and vertically. The area of A. stellio is defined by the March isotherm of 8°C and the July and August isotherms of 24°C. A. ruderata occurs in the large steppe areas of Inner and South-east Anatolia, but not in those of Eastern Anatolia.  相似文献   
996.
997.
998.
This study was planned to observe the effects of nitric oxide synthesis on the antioxidative defense enzymes and pancreatic tissue histology in caerulein-induced acute pancreatitis. Acute pancreatitis was induced by intraperitoneal injections of 50 µg/kg caerulein, L-arginine used for NO induction and Nω-nitro-L-arginine methyl ester (L-NAME) used for NO inhibition. In the caerulein group acinar cell degeneration, interstitial inflammation, oedema and haemorrhage were detected. Pancreatic damage scores were decreased with both NO induction and inhibition (p<0.05). MDA, GSH-Px, CAT, GSH and SOD activities were significantly changed in the caerulein group and indicated increased oxidative stress. Both NO induction and inhibition decreased this oxidative stress. It is concluded that both nitric oxide induction and inhibition ameliorated caerulein-induced acute pancreatitis. The findings indicate that a certain amount of NO production has beneficial effects in experimental acute pancreatitis, but uncontrolled over-production of NO may be detrimental.  相似文献   
999.
Abstract

Production of alkaline α‐amylase employing our laboratory isolate, Bacillus sp., under solid state fermentation, was optimized. The effect of wheat bran and lentil husk was examined. Lentil husk exhibited the highest enzyme production. The appropriate incubation time, inoculum size, moisture level, and buffer solution level were determined. Maximum yields of 216,000 and 172,800 U/g were achieved by employing lentil husk and wheat bran as substrates in 0.1 M carbonate/bicarbonate buffer at pH 10.0 with 30% initial moisture level at 24 h. Inoculum size and buffer solution level were found to be 20% and 1:0.5 for two solid substrates.  相似文献   
1000.
This study focuses on the evolutionary relationships among Turkish species of the cave cricket genus Troglophilus.Fifteen populations were studied for sequence variation in a fragment (543 base pairs) of the mitochondrial DNA (mtDNA) 16S rDNA gene (16S) to reconstruct their phylogenetic relationships and biogeographic history. Genetic data retrieved three main clades and at least three divergent lineages that could not be attributed to any of the taxa known for the area. Molecular time estimates suggest that the diversification of the group took place between the Messinian and the Plio-Pleistocene.  相似文献   
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