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71.
A study was performed during Spring 2002 to determine the survival rates of Black Sea Turbot (Psetta maxima maeotica) broodstock captured by gill nets from different depths (20 m, 20–45 m, and 45 m) in Sinop Bay (Black Sea, Turkey) and their adaptation to culture conditions. The weight of captured females ranged between 1.6 and 5.5 kg, while males ranged between 1.1 and 3.7 kg. Within 23 h of capture the fish were transported to Çanakkale (Marmara Sea, Turkey). During transportation, the stocking density ranged from 19 to 40 kg/m3 and no mortality was recorded. At the end of the fishing operations, the survival rates were calculated for Group 1 (20 m), Group 2 (20–45 m), and Group 3 (45 m) as 24.9, 71.4, and 92%, respectively. There were significant differences (p < 0.05) between the survival rates of the groups. Eggs and sperms were obtained by hand-stripping. The mean fertilisation rate of the eggs was 3.19%. This low fertilisation rate was due to overripened eggs. At the end of adaptation period of 1 month, the survival rates of the broodstock were found to be 14.2, 45.4, and 48.3% for Groups 1, 2, and 3, respectively. No significant difference was found between the survival rates of the broodfish during the adaptation period (p > 0.05).  相似文献   
72.
In this study, we report on pyrazin-2(1H)-ones as lead for the development of potent adenosine triphosphate (ATP) competitive protein kinase inhibitors with implications as anti-cancer drugs. Initially, we identified the pyrazin-2(1H)-one scaffold from hamacanthins (deep sea marine sponge alkaloids) by Molecular Modeling studies as core binding motif in the ATP pocket of receptor tyrosine kinases (RTK), which are validated drug targets for the treatment of various neoplastic diseases. Structure-based design studies on a human RTK member PDGFR (platelet-derived growth factor receptor) suggested a straight forward lead optimization strategy. Accordingly, we focused on a Medicinal Chemistry project to develop pyrazin-2(1H)-ones as optimized PDGFR binders. In order to reveal Structure-Activity-Relationships (SAR), we established a flexible synthetic route via microwave mediated ring closure to asymmetric 3,5-substituted pyrazin-2(1H)-ones and produced a set of novel compounds. Herein, we identified highly potent PDGFR binders with IC50 values in an enzymatic assay below µM range, and possessing significant activity against PDGFR dependent cancer cells. Thus, marine hamacanthin-derived pyrazin-2(1H)-ones showing interesting properties as lead for their further development towards potent PDGFR-inhibitors.  相似文献   
73.
The objective of the current study was to characterize Fusarium oxysporum f. sp. radicis-cucumerinum isolates from cucumbers in Turkey in terms of pathogenicity, vegetative compatibility and amplified fragment length polymorphism (AFLP) variation. In the 2007 and 2008 greenhouse cucumber-growing seasons, surveys were conducted in Adana, Antalya, Hatay and Mersin provinces of the Mediterranean region of Turkey. Forty-seven fungal isolates of F. oxysporum were recovered from diseased cucumber plants. The pathogenicity of each isolate was tested on cucumber seedlings at the one-true-leaf stage. Forty of the 47 isolates of F. oxysporum were virulent on cucumber seedlings. Based on disease symptoms, the differential effect of temperatures of 17°C and 29°C on disease development, and the virulence on cucumber seedlings, these 40 isolates were identified as F. oxysporum f. sp. radicis-cucumerinum. Nitrate non-utilizing mutants were generated on minimal medium containing 1.5% KClO3 and their phenotypes were determined. Mutants in different phenotypic classes were paired on minimal medium; of 40 F. oxysporum f. sp. radicis-cucumerinum isolates, thirty-eight were placed into VCG 0260. Remaining two strains were assigned to VCG 0261. The AFLP primers produced a total of 180 fragments between 200 and 500 bp in length for the 30 isolates tested. At a genetic similarity of 0.71, the UPGMA analysis separated the isolates into two distinct clusters. The first cluster, AFLP I, included 28 isolates, of which all belonged to VCG 0260. Two strains in the second AFLP cluster both belonged to VCG 0261.  相似文献   
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A two year field experiment was conducted in field conditions using wheat (Triticum aestivum ssp. vulgare L. cv. Bezostaja) as the test plant for the evaluation of phosphate solubilizing (+PS) microorganisms. Bacterial strains significantly (P < 0.05) increased plant biomass (by 13 to 36%) without plant P enrichment. Only Bacillus sp. #189 significantly (P < 0.05) raised plant P-content, biomass and rhizosphere soil Olsen P at Zadoks Scale 62 simultaneously. Inoculations variably increased plant potassium (K-), magnesium (Mg-), zinc (Zn-), and managenese (Mn-) contents at harvest (Zadoks 92) but not earlier (Zadoks 31 and 61). The enrichment of the inoculated plants with nutrients other than P indicates the presence of alternative plant growth promoting mechanisms. This study showed that promising phosphate solubilizing microorganisms could increase not only the P content of the plants, but also the soil available P in rhizosphere transiently.  相似文献   
77.
Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava was tested for its effects on osteoblastogenic differentiation in MC3T3-E1 pre-osteoblasts. DHE was observed to successfully enhance osteoblast differentiation, as indicated by elevated cell proliferation, alkaline phosphatase activity, intracellular cell mineralization, along with raised levels of osteoblastogenesis indicators at the concentration of 20 μM. Results suggested a possible intervening of DHE on the bone morphogenetic protein (BMP) signaling pathway, according to elevated protein levels of BMP-2, collagen-I, and Smads. In addition, the presence of DHE was also able to raise the phosphorylated extracellular signal–regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) levels which are also activated by the BMP signaling pathway. In conclusion, DHE is suggested to be a potential bioactive compound against bone loss that could enhance osteoblastogenesis with a suggested BMP pathway interaction.  相似文献   
78.
The theoretical basis of the proposed technique is the cumulative variation of 137Cs measurements’ squared-differences between a reference and other sites. The change of the cumulative squared-differences with distance from the reference site is referred to as the point cumulative semivariogram (PCSV), which provides appropriate measure of cumulative similarity. Inspection of individual experimental PCSV provides local interpretation about the 137Cs radioactivity concentration around each site, whereas collective inspections provide possibility for grouping similar sites and hence identifying homogeneous sub-areas within the study area. It is also possible to prepare 137Cs radioactivity concentration maps based on pre-specified distances in each experimental PCSV, which lead to similarity levels. Such maps provide appreciation of 137Cs radioactivity concentration regional dependence in Keban Dam Lake, Turkey. Apart from the individual PCSV interpretations, the whole lake is divided into four distinctive classes.  相似文献   
79.
Citrus family especially Grapefruit, has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties. The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties. The total soluble solids (TSS), titratable acidity (TA) and pH of juice samples extracted from various grapefruit varieties differed significantly. The refractive index, specific gravity and optical rotation values for the oil varied from 1.473 to 1.396, 0.863 to 0.847 and +93 to +86, respectively. The percent 2,2-diphenyl-1-picrylhydrazyl radical activity (% DPPH activity) and ferric reducing antioxidant power (FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79, 2.91 to 1.44 mmol g–1 and 84.87 to 74.73, 7.76 to 5.73 mmol g–1, respectively. There were significant differences in physicochemical, antioxidant properties and volatile profiles of extracted juice and oil. The oil exhibited higher DPPH and FRAP values than the juice. Among different components identified which accounted for over 99% of the volatile fraction, limonene, myrcene, and benzopyran were major components in all oil samples.  相似文献   
80.
The effects of sodium borate (100 mg/kg body weight, p.o., 15 days) from a month before expected calving until a month after calving were evaluated in dairy cows susceptible to fatty liver. Cows received either sodium borate (n = 13) or no treatment (n = 10). All cows had mild fatty livers and increased plasma triglycerides and very low density lipoprotein (VLDL) concentrations at the beginning of the experiment. The control group of cows developed significant fatty liver after calving, and 2 of them had severe fatty liver associated with clinical and biochemical abnormalities. There were no clinicopathological signs related to sodium borate administration. Serum triglycerides and VLDL concentrations before calving decreased significantly at calving and after calving in controls, and they were within the normal range only after calving. There were significant alterations during the experiment in some hematological and chemical variables between groups, within period, but they were within the normal range. Unlike treated cows, serum triglycerides and VLDL concentrations correlated with liver fat content after calving in untreated cows. Our results document that sodium borate decreases the degree of fatty liver in dairy cows during early lactation.  相似文献   
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