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排序方式: 共有523条查询结果,搜索用时 9 毫秒
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In vitro improvement of quail primordial germ cell expansion through activation of TGF‐beta signaling pathway 下载免费PDF全文
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Pourmoghadasiyan Bahareh Tavakkoli Fatemeh Beram Farzaneh Mahmoudi Badmasti Farzad Mirzaie Amir Kazempour Reza Rahimi Shahrzad Larijani Setare Farokhi Hejabi Faranak Sedaghatnia Kamand 《Molecular biology reports》2022,49(5):3597-3608
Molecular Biology Reports - In this study, the optimized niosomal formulation containing paclitaxel using non-ionic surfactants and cholesterol was designed and its cytotoxic effects against... 相似文献
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Azadeh?BadieeEmail author Hans?Geir?Eiken Vidar?M?Steen Roger?L?vlie 《BMC biotechnology》2003,3(1):23
Background
Several different cDNA labeling methods have been developed for microarray based gene expression analysis. We have examined the accuracy and reproducibility of such five commercially available methods in detection of predetermined ratio values from target spike mRNAs (A. thaliana) in a background of total RNA. The five different labeling methods were: direct labeling (CyScribe), indirect labeling (FairPlay? – aminoallyl), two protocols with dendrimer technology (3DNA® Array 50? and 3DNA® submicro?), and hapten-antibody enzymatic labeling (Micromax? TSA?). Ten spike controls were mixed to give expected Cy5/Cy3 ratios in the range 0.125 to 6.0. The amounts of total RNA used in the labeling reactions ranged from 5 – 50 μg.Results
The 3DNA array 50 and CyScribe labeling methods performed best with respect to relative deviation from the expected values (16% and 17% respectively). These two methods also displayed the best overall accuracy and reproducibility. The FairPlay method had the lowest total experimental variation (22%), but the estimated values were consistently higher than the expected values (36%). TSA had both the largest experimental variation and the largest deviation from the expected values (45% and 48% respectively).Conclusion
We demonstrate the usefulness of spike controls in validation and comparison of cDNA labeling methods for microarray experiments.6.
Computational simulation of internal bone remodelling around dental implants: a sensitivity analysis
Hasan I Rahimi A Keilig L Brinkmann KT Bourauel C 《Computer methods in biomechanics and biomedical engineering》2012,15(8):807-814
This study aimed to predict the distribution of bone trabeculae, as a density change per unit time, around a dental implant based on applying a selected mathematical remodelling model. The apparent bone density change as a function of the mechanical stimulus was the base of the applied remodelling model that describes disuse and overload bone resorption. The simulation was tested in a finite element model of a screw-shaped dental implant in an idealised bone segment. The sensitivity of the simulation to different mechanical parameters was investigated; these included element edge length, boundary conditions, as well as direction and magnitude of the implant loads. The alteration in the mechanical parameters had a significant influence on density distribution and model stability, in particular at the cortical bone region. The remodelling model could succeed to achieve trabeculae-like structure around osseointegrated dental implants. The validation of this model to a real clinical case is required. 相似文献
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A rapid and sensitive fluorescence-based bioassay for determination of indoleamine 2,3-dioxygenase (IDO) activity has been developed. This assay relies on the quantification of the amount of kynurenine produced in the assay medium by fluorescence and complements the standard absorbance and high-performance liquid chromatography (HPLC) assay methods. The fluorescence method has limits of detection similar to those of the standard assay methods. Measured activities of IDO, including in the presence of tryptophan-based inhibitors, were in statistical agreement with the absorbance and HPLC assay methods. The fluorescence-based assay was also suitable for assessment of IDO inhibition by compounds that are incompatible with the absorbance method. 相似文献
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Nader Mansour Samaei Yaghoub Yazdani Reza Alizadeh-Navaei Hossein Azadeh Touraj Farazmandfar 《Journal of biomedical science》2014,21(1):73
Background
Aberrant DNA methylation as the most important reason making epigenetic silencing of genes is a main mechanism of gene inactivation in patients with colorectal cancer. In this study, we decided to identify promoter methylation status of ten genes encoding WNT negative regulators, and measure the expression of DNMT1 enzyme in colorectal cancer samples.Results
Aberrant methylation of APC gene was statistically significant associated with age over 50 (p = 0.017), DDK3 with male (p < 0.0001), SFRP4, WIF1, and WNT5a with increasing tumor stage (p = 0.004, p = 0.029, and p = 0.004), SFRP4 and WIF1 with tumor differentiation (p = 0.009 and p = 0.031) and SFRP2 and SFRP5 with histological type (p = 0.001 and p = 0.025). The increasing number of methylated genes correlated with the expression levels of the DNMT1 mRNA.Conclusions
The rate of gene promoter methylation of WNT pathway regulators is high in colorectal cancer cells. Hyper-methylation is associated with increased expression of the DNMT1 enzyme. 相似文献9.
Effect of neohesperidin dihydrochalcone on the activity and stability of alpha‐amylase: a comparative study on bacterial,fungal, and mammalian enzymes 下载免费PDF全文
Elaheh Kashani‐Amin Azadeh Ebrahim‐Habibi Bagher Larijani Ali Akbar Moosavi‐Movahedi 《Journal of molecular recognition : JMR》2015,28(10):605-613
Neohesperidin dihydrochalcone (NHDC) was recently introduced as an activator of mammalian alpha‐amylase. In the current study, the effect of NHDC has been investigated on bacterial and fungal alpha‐amylases. Enzyme assays and kinetic analysis demonstrated the capability of NHDC to significantly activate both tested alpha‐amylases. The ligand activation pattern was found to be more similar between the fungal and mammalian enzyme in comparison with the bacterial one. Further, thermostability experiments indicated a stability increase in the presence of NHDC for the bacterial enzyme. In silico (docking) test locates a putative binding site for NHDC on alpha‐amylase surface in domain B. This domain shows differences in various alpha‐amylase types, and the different behavior of the ligand toward the studied enzymes may be attributed to this fact. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Marjan Seiedy Alireza Saboori Azadeh Zahedi-Golpayegani 《Experimental & applied acarology》2013,60(2):219-227
Determination of attraction and avoidance behavior of predators is important in concomitant use of multiple natural enemies to control a pest. The olfactory response of the predatory mite Phytoseiulus persimilis was studied to odors related to Tetranychus urticae adults infected by Beauveria bassiana DEBI008 in 0, 24, 48 and 72 h intervals, both in absence and in presence of plants. In plant-present experiments, P. persimilis attraction was neither towards adults of T. urticae infected by 0.02 % Tween 80 (as control), nor to the ones infected by B. bassiana for 0 or 24 h, whereas significant attraction towards the control was observed when tested against T. urticae infected by B. bassiana for 48 or 72 h. In absence of plants, P. persimilis displayed significant avoidance of T. urticae infected by B. bassiana for 48 or 72 h, when their alternative option was 0.02 % Tween 80-infected T. urticae adults. These results indicate that P. persimilis can recognize the presence of B. bassiana and that the predator avoids the fungus. This suggests that the two natural enemy species can be used together in biological control programmes. 相似文献