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991.
Ahmadi Behzad Ebrahimzadeh Hamed Zarifi Eissa 《Plant Cell, Tissue and Organ Culture》2021,146(1):115-126
Plant Cell, Tissue and Organ Culture (PCTOC) - In this study, various concentrations of oryzalin (0, 5, 10, 50, and 100 mg l?1), trifluralin (0, 5, 10, 50, and... 相似文献
992.
Mohamad Reza Bayatiani Fatemeh Fallahi Akbar Aliasgharzadeh Mahdi Ghorbani Benyamin Khajetash Fatemeh Seif 《Reports of Practical Oncology and Radiotherapy》2021,26(1):50
BackgroundSymmetry and flatness are two quantities which should be evaluated in the commissioning and quality control of an electron beam in electron beam radiotherapy. The aim of this study is to compare symmetry and flatness obtained using three different dosimeters for various small and large fields in electron beam radiotherapy with linac.Materials and methodsBeam profile measurements were performed in a PTW water phantom for 10, 15 and 18 MeV electron beams of an Elekta Precise linac for small and large beams (1.5 × 1.5 cm2 to 20 × 20 cm2 field sizes). A Diode E detector and Semiflex-3D and Advanced Markus ionization chambers were used for dosimetry.ResultsBased on the obtained results, there are minor differences between the responses from different dosimeters (Diode E detector and Semiflex-3D and Advanced Markus ionization chambers) in measurement of symmetry and flatness for the electron beams. The symmetry and flatness values increase with increasing field size and electron beam energy for small and large field sizes, while the increases are minor in some cases.ConclusionsThe results indicate that the differences between the symmetry and flatness values obtained from the three dosimeter types are not practically important. 相似文献
993.
To date, a few numbers of bacteriophages that infect Lactococcus garvieae have been identified, but their complete genome sequences have not yet been investigated. For the first time, herein, the complete DNA sequence of a new phage of L. garvieae (phage WP-2) is reported and analyzed. The morphological characteristics indicated that the phage had a small isometric head along with a short and non-contractile tail, suggesting that WP-2 belongs to the family Podoviridae. Bioinformatic analysis revealed that phage WP-2 can be classified as a new member of Ahjdlikevirus in the Picovirinae subfamily because it had a small dsDNA of 18,899 bp with 24 open reading frames and a protein-primed DNA polymerase. The phage nucleotide sequence and predicted protein products have been identified to share very limited evidence of homology with complete genome and proteome of other phages. To our knowledge, this is the first Ahjdlikevirus bacteriophage which can infect a member of the Lactococcus genus. 相似文献
994.
This study proposes the quasi-linear viscoelastic (QLV) model to characterize the time dependent mechanical behavior of poly(vinyl alcohol) (PVA) sponges. The PVA sponges have implications in many viscoelastic soft tissues, including cartilage, liver, and kidney as an implant. However, a critical barrier to the use of the PVA sponge as tissue replacement material is a lack of sufficient study on its viscoelastic mechanical properties. In this study, the nonlinear mechanical behavior of a fabricated PVA sponge is investigated experimentally and computationally using relaxation and stress failure tests as well as finite element (FE) modeling. Hyperelastic strain energy density functions, such as Yeoh and Neo-Hookean, are used to capture the mechanical behavior of PVA sponge at ramp part, and viscoelastic model is used to describe the viscose behavior at hold part. Hyperelastic material constants are obtained and their general prediction ability is verified using FE simulations of PVA tensile experiments. The results of relaxation and stress failure tests revealed that Yeoh material model can define the mechanical behavior of PVA sponge properly compared with Neo-Hookean one. FE modeling results are also affirmed the appropriateness of Yeoh model to characterize the mechanical behavior of PVA sponge. Thus, the Yeoh model can be used in future biomechanical simulations of the spongy biomaterials. These results can be utilized to understand the viscoelastic behavior of PVA sponges and has implications for tissue engineering as scaffold. 相似文献
995.
996.
Akbari Elnaz Arora Vijay K. Enzevaee Aria Ahmadi Mohammad Taghi Khaledian Mohsen Yusof Rubiyah 《Plasmonics (Norwell, Mass.)》2014,9(4):987-992
Plasmonics - Graphene is a single-atom thin layer with sp2 hybridized and two-dimensional (2D) honeycomb structure of carbon. Because of its exclusive properties including high conductivity, high... 相似文献
997.
Dibyendu Sengupta Andrew M. Kahn Ethan Kung Mahdi Esmaily Moghadam Olga Shirinsky Galina A. Lyskina Jane C. Burns Alison L. Marsden 《Biomechanics and modeling in mechanobiology》2014,13(6):1261-1276
Kawasaki disease (KD) is the leading cause of acquired heart disease in children and can result in life-threatening coronary artery aneurysms in up to 25 % of patients. These aneurysms put patients at risk of thrombus formation, myocardial infarction, and sudden death. Clinicians must therefore decide which patients should be treated with anticoagulant medication, and/or surgical or percutaneous intervention. Current recommendations regarding initiation of anticoagulant therapy are based on anatomy alone with historical data suggesting that patients with aneurysms \(\ge \) 8 mm are at greatest risk of thrombosis. Given the multitude of variables that influence thrombus formation, we postulated that hemodynamic data derived from patient-specific simulations would more accurately predict risk of thrombosis than maximum diameter alone. Patient-specific blood flow simulations were performed on five KD patients with aneurysms and one KD patient with normal coronary arteries. Key hemodynamic and geometric parameters, including wall shear stress, particle residence time, and shape indices, were extracted from the models and simulations and compared with clinical outcomes. Preliminary fluid structure interaction simulations with radial expansion were performed, revealing modest differences in wall shear stress compared to the rigid wall case. Simulations provide compelling evidence that hemodynamic parameters may be a more accurate predictor of thrombotic risk than aneurysm diameter alone and motivate the need for follow-up studies with a larger cohort. These results suggest that a clinical index incorporating hemodynamic information be used in the future to select patients for anticoagulant therapy. 相似文献
998.
Inhibition of α-amylase is an important strategy to control post-prandial hyperglycemia.
The present study on Ruellia tuberosa, known as traditional anti-diabetic agent, is being provided in silico
study to identify compounds inhibiting α-amylase in rat and human. Compounds were explored from PubChem database.
Molecular docking was studied using the autodock4. The interactions were further visualized and analyzed using
the Accelrys Discovery Studio version 3.5. Binding energy of compounds to α-amylase was varying between -1.92
to -6.66 kcal/mol in rat pancreatic alpha amylase and -3.06 to -8.42kcal/mol in human pancreatic alpha amylase,
and inhibition konstanta (ki) was varying between 13.12- 39460µM in rat and 0.67-5600µM in human. The docking
results verify that betulin is the most potential inhibitor of all towards rat model alpha amylase and human
alpha amylase. Further analysis reveals that betulin could be a potential inhibitor with non-competitive pattern
like betulinic acid. In comparison, betulin has smaller Ki (0.67µM) than acarbose (2.6 µM), which suggesting
that betulin is more potential as inhibitor than acarbose, but this assumption must be verified in vitro. 相似文献
999.
Romina Dastmalchi Ali Farazmand Sina Noshad Mohamad Mozafari Mahdi Mahmoudi Alireza Esteghamati Aliakbar Amirzargar 《Molecular biology reports》2014,41(8):5367-5374
Killer immunoglobulin-like receptors (KIR) play a pivotal role in commencement of both innate and adaptive immunity. Dysregulation of KIRs is associated with an increased risk of autoimmune disorders. This study was designed to assess whether polymorphisms in KIR gene family and their respective HLA class I ligands confer protection or susceptibly to Graves’ disease (GD). Eighty patients with confirmed GD (cases) and 176 healthy unrelated subjects (controls) were recruited. Using a polymerase chain reaction sequence-specific primer directed method (PCR-SSP), presence or absence of KIR genes and their HLA ligands were determined. No significant differences were observed between case and control groups regarding individual KIR gene frequencies (p > 0.05 in all cases). The frequency of group A haplotype (the most common KIR haplotype, encompassing 2DL1/2DL3/3DL1/2DS4/2DP1/3DP1/2DL4/3DL2/3DL3), was not different between individuals with and without GD. Moreover, among all other haplotypes (group Bx), no significant differences regarding distribution of centromeric and telomeric gene clusters were identifiable. Inhibitory/activatory gene contents were also comparable between the two groups. Four models of KIR-HLA interaction (inhibition, activation, unrestrained inhibition, and unrestrained activation) were constructed. No combination proved to confer susceptibility to, or offer protection against GD. It seems that the contribution of KIR gene polymorphism to natural killer cell dysfunction and other autoimmune abnormalities observed in GD is limited. 相似文献
1000.
Anita Ahmadi Hanieh Shirazi Narges Pourbagher Abolfazl Akbarzadeh Kobra Omidfar 《Molecular biology reports》2014,41(3):1659-1668
A simple, sensitive, and low-cost immunosensor was designed for the detection of digoxin through core–shell gold coated magnetic nanoparticles (Fe3O4-Au-NPs) as an electrochemical label. Having had such a large potential for a variety of applications, Fe3O4-Au-NPs have attracted a considerable attention and are actively investigated recently. Digoxin is a cardiac glycoside which, at high level, can indicate an increased risk of toxicity. This new competitive electrochemical immunosensor was developed based on antigen–antibody reaction employing antigen (Ag) labeled Fe3O4-Au-NPs and PVA modified screen-printed carbon electrode surface in order to detect the serum digoxin. The structures of Fe3O4-Au-NPs were studied by transmission electron microscopy, X-ray diffraction and Fourier transformed infrared spectroscopy. Cyclic voltammetry and differential pulse voltammetry (DPV) were employed to determine the physicochemical and electrochemical properties of immunosensor. DPV was employed for quantitative detection of digoxin in biological samples. The developed immunosensor was capable to detect digoxin in the range from 0.5 to 5 ng mL?1, with a detection limit as low as 0.05 ng mL?1. The proposed method represented acceptable reproducibility, stability, and reliability for the rapid detection of digoxin in serum samples. 相似文献