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G Nikbakht M Roostaei Ali Mehr A Baghbanzadeh P Tajik C Tamanini M Emam 《Reproduction in domestic animals》2010,45(2):237-242
Leptin is a potential satiety factor and plays an important role in both metabolism and reproduction; both leptin and its receptor (Ob‐R) have been detected in human spermatozoa, thus suggesting leptin involvement in male gamete physiology. This experiment was designed to investigate leptin receptor [the long isoform (Ob‐Rb)] mRNA in bull ejaculated spermatozoa by RT‐PCR and southern hybridization. Total RNA was isolated from ejaculated spermatozoa and purified by different methods. Although the concentrations of RNA determined by all methods (except SDS/Proteinase K, lowest amount of RNA recovery) were similar, ethidium bromide staining was only detectable in lanes containing the samples isolated by sodium dodecyl sulphate (SDS) and SDS/citric acid extraction which produced higher RNA concentration. Ob‐Rb mRNA was detected in all samples using southern hybridization after RT‐PCR; it was shown only in three of them by RT‐PCR. We may conclude that Ob‐Rb mRNA is present in bull spermatozoa and leptin perhaps exerts physiological effects, as already demonstrated in humans and pigs. 相似文献
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Samaneh Solaymani Ahmad Ayatollahi Mehrgardi Ali Esmailizadeh Llibertat Tusell Mehdi Momen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(5):423-437
In recent years, with development and validation of different genotyping panels, several methods have been proposed to build efficient similarity matrices among individuals to be used for genomic selection. Consequently, the estimated genetic parameters from such information may deviate from their counterpart using traditional family information. In this study, we used a pedigree-based numerator relationship matrix ( A ) and three types of marker-based relationship matrices () including two identical by descent, that is and and one identical by state, as well as four Gaussian kernel () similarity kernels with different smoothing parameters to predict yet to be observed phenotypes. Also, we used different kinship matrices that are a linear combination of marker-derived IBD or IBS matrices with A, constructed as , where the weight () assigned to each source of information varied over a grid of values. A Bayesian multiple-trait Gaussian model was fitted to estimate the genetic parameters and compare the prediction accuracy in terms of predictive correlation, mean square error and unbiasedness. Results show that the estimated genetic parameters (heritability and correlations) are affected by the source of the information used to create kinship or the weight placed on the sources of genomic and pedigree information. The superiority of GK -based model depends on the smoothing parameters (θ) so that with an optimum θ value, the GK -based model statistically yielded better performance (higher predictive correlation, lowest MSE and unbiased estimates) and more stable correlations and heritability than the model with IBD, IBS or kinship matrices or any of the linear combinations. 相似文献
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Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah Amal Biswas 《Journal of the World Aquaculture Society》2012,43(5):679-687
The effect of five different light regimes on growth, stress and hematological indices was studied in Persian sturgeon, Acipenser persicus. Fish with average weight of 645.3 ± 11.2 g were subjected to different photoperiods (24 L, 12 L:12 D, 16 L:8 D, 8 L:16 D and 24 D) for 8 wk. Blood samples were collected at the end of the experiment for measuring cortisol, glucose and hematological features. The whole growth parameters showed no significant difference. Plasma cortisol concentration was significantly higher in 12 L:12 D, while the lowest level was observed in fish exposed to 24 D. No significant changes were observed among the treatments for glucose concentration. Lactate concentration varied significantly among the treatments. Some hematological indices including hematocrit and number of white blood cells were affected by different light regimes, but the others (hemoglobin and number of red blood cells) were not affected significantly. The results showed that photoperiod manipulation can alters some stress‐related metabolites and may enhance growth rate in fish exposing to continuous darkness. 相似文献
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Background: The progressive accumulation of misfolded and aggregated proteins in neurons is an accepted mechanism in aging. Overproduction of reactive oxygen species (ROS), referred to as oxidative stress, is currently believed to play a pivotal role in this process. Lipofuscin as a histological index of aging results from cross-links between oxidized proteins and lipids. Therefore, to attenuate lipofuscin formation, it would be logical to use exogenous natural or synthetic antioxidants. Yakuchinone B (1-[4''-hydroxy-3''-methoxyphenyl]-7-phenylhept-1-en-3-one) is a component of Alpinia oxyphylla seeds with established antioxidant activity. Methods: To evaluate the neuroprotective roles of yakuchinone B (JC6) and its structural analogues (JC1-JC5), the free radical scavenging capabilities of yakuchinone B derivatives were studied in terms of cell viability, apoptosis, cells ROS content, catalase (CAT) and superoxide dismutase (SOD) activity and the intracellular lipofuscin content in SK-N-MC cells exposed to H2O2. The level of MDA (malondialdehyde), as an index of lipid peroxidation and acid phosphatase activity were also measured. Results: Our results indicated that derivatives especially JC4, JC5 and JC6 decreased the extent of apoptosis and ROS level, while they increased the activities of SOD and CAT in drug-pretreated cells as compared to H2O2-treated cells. A clear relationship between the structure and antioxidant activities of these compounds was established. In addition, JC4, JC5 and JC6 were capable of down-regulating the formation of MDA and lipofuscin. Conclusion: Our results indicated that free radicals play significant roles in lipofuscin formation and cellular aging which can be attenuated by yakuchinone B derivatives.Key Words: Aging, Lipofuscin, Reactive oxygen species (ROS), Yakuchinone B 相似文献
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Roudgarnejad Samaneh Samdeliri Morteza Mirkalaei Amirabas Mousavi Moghaddam Mojtaba Nasheai 《Gesunde Pflanzen》2021,73(4):603-611
Gesunde Pflanzen - Humic acid comprises the major part of humic substances and the most important component of soil organic matter (humus) that increases crop yield and quality. This research aimed... 相似文献
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Kourosh Qaderi Vahidreza Jalali Samaneh Etminan Mojtaba Masoumi Shahr-babak Mehdi Homaee 《Paddy and Water Environment》2018,16(4):823-833
The saturated hydraulic conductivity (\(K_{\text{s}}\)) is one of the important soil hydraulic properties which plays a significant role in developing flow transport models and irrigation and drainage practices. In this research, artificial neural networks approaches, group method of data handling (GMDH) model and a hybrid intelligent model based on combination of GMDH and harmony search (HS) model (GMDH-HS) were developed to estimate \(K_{\text{s}}\) based on 151 field samples collected from the northeast of Iran. Eleven topsoil properties were used as input parameters to estimate \(K_{\text{s}}\). The five quantitative standard statistical performance evaluation measures, i.e., coefficient of efficiency, root-mean-square error, mean square relative error, mean absolute percentage error and relative bias, were employed to evaluate the performance of various developed models. Statistical results indicated that the best performance can be obtained by GMDH-HS in terms of different evaluated criteria during the training and testing datasets for \(K_{\text{s}}\) estimation. 相似文献
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Mahin Rafieipour Alireza Motallebi-Azar Nasser Mahna Habib Davati Kazemnia Samaneh Kazemiani Fahimeh Yarmohamadi 《Russian Agricultural Sciences》2011,37(5):385-391
In this research, the factors affecting seed production of six landraces (Sefid-e-Ghom, Germez-e-Azarshahr, Dorcheh-e-Isfahan,
Tarom, Germez-e-Kazeroon, Sefid-e-Abarkooh) and a foreign cultivar (Yellow Sweet Spanish as a control) were evaluated in a
randomized complete block design experiment with three replications. Results indicated significant differences between genotypes
regarding some of the traits. Seed stalks were emerged in Tarom and Yellow Sweet Spanish earlier than other landraces. Flowering
of Germez-e-Kazeroon and Tarom were the first and last, respectively. Also, ripening of seed in Germez-e-Kazeroon and Yellow
Sweet Spanish was earlier and later than other landraces, respectively. The number of seed stalks/plant and seed yield/ha
were increased while increasing in bulb size from 5 to 7 cm. Among the landraces, Sefid-e-Ghom and Germez-e-Azarshahr showed
the highest and lowest number of seed stalks/plant, respectively. Sefid-e-Ghom, also, showed the highest seed yield/inflorescence,
/plant and/ha. Although the differences were not significant statistically. Relationships between traits showed that seed
yield/plant and /ha was a positively correlated with the number of seed stalks/plant. Genotypes were grouped in three clusters
using Ward method. 相似文献
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Growth,development and behaviour of Persian sturgeon Acipenser persicus larvae in different light regimes 
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下载免费PDF全文 Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah 《Aquaculture Research》2017,48(12):5812-5820
The effects of five different light regimes on growth performance and behaviour of Persian Sturgeon larvae were examined. Larvae were reared under five different photoperiods (24L, 12L:12D, 16L:8D, 8L:16L and 24D), from hatching (25.8 ± 8.1 mg; 12 ± 0.6 mm) to 28 days post‐hatch (dph). Except the last week, there was no significant difference in growth parameters among the experimental groups. Growth performance significantly improved in larvae reared under a continuous light regime. The highest final length (34.5 ± 1.7 mm) was measured in 24L and the lowest one (29.5 ± 0.4 mm) in the constant darkness. Relative to other experimental groups, the continuous darkness had a retarding impact on the yolk sac absorption and swarming behaviour. Among the whole body compositions, the lowest body moisture content was measured in the continuous light group. Persian Sturgeon pre‐larvae and larvae were not completely dependent on light regimes (in 1–21 days), whereas on the basis of measured parameters (total length, wet and dry weight and digestive fullness index) a continuous light regime played a decisive role on growth performance beyond 21 dph. 相似文献
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Tajik P Beheshti-Govij R Soleimani-Rad J Ghasemzadeh-Nava H Mohamadi-Roshandeh A 《Pakistan journal of biological sciences: PJBS》2008,11(4):628-632
Murine 2-cells embryos were isolated from murine oviducts at laboratory and transferred into Ham's F-10 medium containing 0.1 mg mL(-1) streptomycin and 100 IU mL(-1) penicillin G and supplemented with 3 mg mL(-1) bovine serum albumin (BSA) or different concentrations of bovine follicular fluid (bFF) and estrous cow serum (ECS). Significantly higher (p<0.05) > or =4-cell embryos were developed when embryos were cultured 20% bFF (84.33%) comparing to 10 and 15% bFF (48.33 and 69.33%) as well as 3 mg mL(-1) BSA (65.66%). Morula rates were also lower in 10% bFF (22.33%) comparing to the other groups and were similar in 15 and 20% bFF (62.66 and 72.33% morula rates) as well as BSA containing media (55.33%). The highest (p<0.05) blastocyst rates were obtained in medium containing 20% bFF (64.33%) and the lowest belonged to 10% bFF (15%) comparing to 15% bFF (33.66%) or 3 mg mL(-1) BSA. When embryos were cultured in ECS, no significant different was observed in different culture media (76.66, 72.33, 82.5 and 65.66% > or =4-cell embryos in 10, 15 and 20% bFF and 3 mg mL(-1) BSA, respectively). Morula and blastocyst rates were also similar in all groups (32.33, 41.66 and 66.25 and 55.33% morula rates and 15.33, 27, 44.50 and 29.66% blastocyst rates for 10, 15 and 20% bFF and 3 mg mL(-1) BSA, respectively). The results of the present study demonstrated that 20% bFF could be substituted for BSA when in vitro culture of murine embryos is carried. 相似文献