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111.
Ghulam Murtaza Shahid Mehmood Shahid Rasul Imran Murtaza Ehsan Ullah Khan 《Reports of Practical Oncology and Radiotherapy》2018,23(3):189-198
Aim
The aim of study was to evaluate the dosimetric effect of collimator-rotation on VMAT plan quality, when using limited aperture multileaf collimator of Elekta Beam Modulator? providing a maximum aperture of 21 cm × 16 cm.Background
The increased use of VMAT technique to deliver IMRT from conventional to very specialized treatments present a challenge in plan optimization. In this study VMAT plans were optimized for prostate and head and neck cancers using Elekta Beam-ModulatorTM, whereas previous studies were reported for conventional Linac aperture.Materials and methods
VMAT plans for nine of each prostate and head-and-neck cancer patients were produced using the 6 MV photon beam for Elekta-SynergyS® Linac using Pinnacle3 treatment planning system. Single arc, dual arc and two combined independent-single arcs were optimized for collimator angles (C) 0°, 90° and 0°–90° (0°–90°; i.e. the first-arc was assigned C0° and second-arc was assigned C90°). A treatment plan comparison was performed among C0°, C90° and C(0°–90°) for single-arc dual-arc and two independent-single-arcs VMAT techniques to evaluate the influence of extreme collimator rotations (C0° and 90°) on VMAT plan quality. Plan evaluation criteria included the target coverage, conformity index, homogeneity index and doses to organs at risk. A ‘two-sided student t-test’ (p ≤ 0.05) was used to determine if there was a significant difference in dose volume indices of plans.Results
For both prostate and head-and-neck, plan quality at collimator angles C0° and C(0°–90°) was clinically acceptable for all VMAT-techniques, except SA for head-and-neck. Poorer target coverage, higher normal tissue doses and significant p-values were observed for collimator angle 90° when compared with C0° and C(0°–90°).Conclusions
A collimator rotation of 0° provided significantly better target coverage and sparing of organs-at-risk than a collimator rotation of 90° for all VMAT techniques. 相似文献112.
Diminished circulating concentration of interleukin‐35 in Helicobacter pylori‐infected patients with peptic ulcer: Its association with FOXP3 gene polymorphism,bacterial virulence factor CagA,and gender of patients 下载免费PDF全文
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Simone Martinelli Oliver H.F. Krumbach Francesca Pantaleoni Simona Coppola Ehsan Amin Luca Pannone Kazem Nouri Luciapia Farina Radovan Dvorsky Francesca Lepri Marcel Buchholzer Raphael Konopatzki Laurence Walsh Katelyn Payne Mary Ella Pierpont Samantha Schrier Vergano Katherine G. Langley Douglas Larsen Ghayda M. Mirzaa 《American journal of human genetics》2018,102(2):309-320
116.
Ayaz Ghani Molly Weinberg Nusrat Pathan Ramapriya Vidhun Steven Sieber 《Mycopathologia》2018,183(6):973-977
Paracoccidioides infection is a rare entity in the USA. This dimorphic fungus is found in Central and South America and is thought to be acquired by inhalation through the soil. We report a case of Paracoccidioides brasiliensis infection presenting as a clavicular bone lesion, peripancreatic mass, and various skin lesions. A 35-year-old man with a history significant for Hodgkin lymphoma presented with a left clavicular mass that was suspected clinically and radiologically as recurrent Hodgkin lymphoma. He was not experiencing any associated symptoms and was undergoing chemotherapy treatment for his known Hodgkin disease. On CT imaging, the mass was seen as a lytic bone lesion with an overlying soft tissue mass. This was biopsied and histologically diagnosed as a Paracoccidioides brasiliensis infection with associated necrotizing granulomatous inflammation. Also found on the CT scan was an enlarging peripancreatic mass which on endoscopic biopsy had similar histologic findings. In conclusion, this report presents a rare case of Paracoccidioides brasiliensis infection mimicking recurrent Hodgkin lymphoma. 相似文献
117.
Ehsan Mohammadpour Jomana Al-Nu’airat Zhong-Tao Jiang Nicholas Mondinos Bogdan Z. Dlugogorski 《Molecular simulation》2018,44(5):415-423
The equilibrium structure, elastic constants Cij and thermodynamic functions of cubic titanium nitride (TiN) were calculated within the temperature range of 0–3100 K and under a pressure range 0–60 GPa. Properties were computed using the generalised gradient approximations (GGA) exchange-correlation functional. Calculated mechanical properties (Elastic constants, Young’s modulus and shear modulus) and phonon spectra of TiN obtained via robust DFT-QHA algorithm, were generally in a good agreement with available experimental and theoretical analogous values. In particular, a well-examined quasi-harmonic approximation method implemented in the Gibbs2 code is utilised herein to provide accurate estimation of thermal expansion coefficients, entropies, heat capacity values (at different combinations of temperature/volume/pressure) and Debye’s temperature. Parameters calculated herein shall be useful to elucidate the superior performance of TiN at harsh operational conditions encompassing elevated temperatures and pressures pertinent to cutting machineries and surface coatings. 相似文献
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119.
Nusrat?SabaEmail author Osman?Yusuf Sadia?Rehman Saeeda?Munir Sheeraz?Ahmad Atika?Mansoor Ghazala?K?Raja 《Journal of biosciences》2016,41(3):439-444
Asthma is a chronic disease due to inflammation of the airways of lungs that is clinically characterized by variable symptoms including wheezing, coughing and shortness of breath. Angiotensin I-converting enzyme (ACE) plays a major role in fibrous tissue formation and is highly expressed in lungs. The main aim of this research work was to study the role of ACE insertion/deletion (I/D) polymorphism, rs4646994, in asthma in Pakistani patients. A total of 854 subjects, including 333 asthma patients and 521 ethnically matched controls, were studied. The ACE (I/D) polymorphism was genotyped using polymerase chain reaction (PCR). Chi-square, Fisher’s exact and Hardy–Weinberg equilibrium tests were used to compare groups. Homozygous insertion genotype II (p<0.0001, OR=3.38) and insertion allele (I) was significantly more frequent in Pakistani asthmatics than in healthy controls (p=0.0007, OR=1.40). The ID genotype (p<0.0001, OR=0.43) and the deletion allele (D) were associated with protection of disease in Pakistani patients (p=0.0007, OR=0.71). These data suggest the involvement of ACE I/D polymorphism in asthma risk in the Pakistani population. This marker may be an important indication in the molecular mechanism of asthma and can become a useful tool in risk assessment and help in designing strategy to combat disease. 相似文献
120.
Saima Nusrat Mohammad Khursheed Siddiqi Masihuz Zaman Nida Zaidi Mohammad Rehan Ajmal Parvez Alam Atiyatul Qadeer Ali Saber Abdelhameed Rizwan Hasan Khan 《PloS one》2016,11(7)
Exogenous drugs that are used as antidote against chemotheray, inflammation or viral infection, gets absorbed and interacts reversibly to the major serum transport protein i.e. albumins, upon entering the circulatory system. To have a structural guideline in the rational drug designing and in the synthesis of drugs with greater efficacy, the binding mechanism of an antineoplastic and anti-inflammatory drug Nordihydroguaiaretic acid (NDGA) with human and bovine serum albumins (HSA & BSA) were examined by spectroscopic and computational methods. NDGA binds to site II of HSA with binding constant (Kb) ~105 M-1 and free energy (ΔG) ~ -7.5 kcal.mol-1. It also binds at site II of BSA but with lesser binding affinity (Kb) ~105 M-1 and ΔG ~ -6.5 kcal.mol-1. The negative value of ΔG, ΔH and ΔS for both the albumins at three different temperatures confirmed that the complex formation process between albumins and NDGA is spontaneous and exothermic. Furthermore, hydrogen bonds and hydrophobic interactions are the main forces involved in complex formation of NDGA with both the albumins as evaluated from fluorescence and molecular docking results. Binding of NDGA to both the albumins alter the conformation and causes minor change in the secondary structure of proteins as indicated by the CD spectra. 相似文献