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排序方式: 共有2064条查询结果,搜索用时 62 毫秒
81.
Md. Dilshad Manzar Wassilatul Zannat Jamal Ali Moiz David Warren Spence Seithikurippu R. Pandi-Perumal Ahmed S. Bahammam 《Biological Rhythm Research》2016,47(6):851-864
The Pittsburgh Sleep Quality Index (PSQI) is a rigorously validated questionnaire with extensive use in sleep assessment. Findings from numerous factor analytic studies of the PSQI have been interpreted to support a heterogeneous factor structure model for the test. Nevertheless, the literature continues to lack a focused evaluation of whether this heterogeneous factor structure is justified. A consideration of this issue led to a conclusion that a closer analysis of the PSQI’s factor structure was merited. To address this need a comparative confirmatory factor analysis for assessing the performance of the accepted factors models of the PSQI was conducted. A sample of university students (n = 418), age = 20.92 ± 1.81 years, BMI = 23.30 ± 2.57 kg/m2 completed the multi-structured sleep survey at Jamia Millia Islamia, New Delhi, India. Seventeen putative factor structures (three 1-Factor, eight 2-Factor, and six 3-Factor) of the PSQI from the existing literature were selected for analysis. Fourteen models (82.35%) had almost similar values for model fit indices. Two models were misfits, and one model was a poor fit. The two misfit models incorporated gender and age as covariates. The third poor fit model was used to produce a unique path diagram, which made it distinct from the remaining 16 models. The overlapping values in the fit range of the model fit indices did not support the often projected heterogeneous factor structures of the PSQI for the vast majority of the models. 相似文献
82.
Md Ruhul Amin Nabanita Paul Nancy Md Ramiz Uddin Miah Md Giashuddin Miah Ohseok Kwon Sang Jae Suh 《Entomological Research》2019,49(5):223-228
The study was conducted with the aim of furthering our understanding of seasonality in the population dynamics and infestation rates of the fruit fly Bactrocera spp. in sweet gourd (Cucurbita moschata) during winter and summer in 2017. We also investigated the effects of using methyl eugenol traps on fly abundance and infestation. Two fruit fly species, namely, B. cucurbitae and B. dorsalis, were present in the sweet gourd field, and we observed fluctuations in their abundance. Compared to B. dorsalis, B. cucurbitae was significantly more abundant in both winter and summer. Infestation level was found to be the highest in fields lacking methyl eugenol traps in both seasons. Fruit fly larval population per infested fruit was higher in summer than in winter. Fly abundance was significantly and positively correlated with mean temperature and rainfall but significantly and negatively correlated with light intensity. Relative humidity was insignificantly but positively correlated with fly abundance. The temperature, light intensity, relative humidity, and rainfall individually explained 48.9, 24.1, 0.8, and 1.6% of variation in fruit fly abundance, respectively. The combined effect of the weather parameters on fruit fly abundance was 75.4% and was significant predictor of fruit fly abundance. 相似文献
83.
Md Saad Amir Putra Prakoso Akbar Teguh Sulong M. A. Basri Hasan Wahjuningrum Dian Agustin Syahrom Ardiyansyah 《Biomechanics and modeling in mechanobiology》2019,18(3):797-811
Biomechanics and Modeling in Mechanobiology - This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg... 相似文献
84.
Anukul Maji Maidul Beg Somnath Das Nandan Kumar Sahoo Pradeep K. Jha Md. Maidul Islam Maidul Hossain 《Luminescence》2019,34(6):563-575
This study describes the eco‐friendly, low‐cost and room‐temperature synthesis of gold nanoparticles from Musa balbisiana leaf extract, which acts as both reducing and stabilizing agent, and characterized by ultraviolet?visible (UV–vis) light spectroscopy, fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), analytical transmission electron microscopy (TEM), energy‐dispersive X‐ray spectroscopy (EDAX) and dynamic light scattering (DLS) instruments. These nanoparticles showed an average diameter of 33.83 ± 3.39 nm, which was confirmed from the size distribution histogram. The bactericidal activity of these nanoparticles was confirmed using bacteria Escherichia coli and Staphylococcus aureus at 1 and 2 nM minimum inhibitory concentrations, respectively. The interaction between nanoparticles and human serum albumin (HSA) was investigated, as this plays significant roles in biological systems. The nature of interaction, binding parameters and structural variation of HSA in the presence of these nanoparticles have been evaluated using several useful spectroscopic approaches such as UV–vis, FTIR, time‐resolved and steady‐state fluorescence, and circular dichroism in addition to the measurement of zeta potential. This interaction study revealed that static quenching occurs in this process with minimal alteration in the secondary structure, but the native structure of HSA remained unaltered. The binding constant and thermodynamic parameters of this interaction process were also evaluated. 相似文献
85.
Khalek Md. Abdul Chakma Sujan Ahmed Kawsar Paul Bikash Kumar Vigneswaran Dhasarathan Zakaria Rozalina 《Plasmonics (Norwell, Mass.)》2019,14(4):861-867
Plasmonics - This article explores the effect of sensing performances with subject to change in different types of material and this study is carried out by the support of plasmon-coated photonic... 相似文献
86.
Takashi Yazawa Yoshitaka Imamichi Koh‐ichi Yuhki Junsuke Uwada Daisuke Mikami Masayuki Shimada Kaoru Miyamoto Takeshi Kitano Satoru Takahashi Toshio Sekiguchi Nobuo Suzuki Md. Rafiqul Islam Khan Fumitaka Ushikubi Akihiro Umezawa Takanobu Taniguchi 《Molecular reproduction and development》2019,86(7):786-797
87.
Zachary A. Bornholdt Andrew S. Herbert Chad E. Mire Shihua He Robert W. Cross Anna Z. Wec Dafna M. Abelson Joan B. Geisbert Rebekah M. James Md Niaz Rahim Wenjun Zhu Viktoriya Borisevich Logan Banadyga Bronwyn M. Gunn Krystle N. Agans Ariel S. Wirchnianski Eileen Goodwin Kevin Tierney John M. Dye 《Cell host & microbe》2019,25(1):49-58.e5
88.
89.
Nibedita Das Mst. Shahnaj Parvin Mahadi Hasan Masuma Akter Md. Sanowar Hossain G.M.Masud Parvez Ashish Kumar Sarker Md. Aziz Abdur Rahman Al Mamun Md. Ekramul Islam 《Biochemistry and Biophysics Reports》2022
Among the major constituents of Leea rubra (Family Vitaceae) leaves, phenolic and flavonoind compounds are most important for therapeutic purposes and the plant parts have been used in traditional medicine to treat several diseases for long. Thus, in order to scientifically confirm the traditional uses of the L. rubra leaves, the present study was designed to investigate the efficacy of the isolated flavones against AAPH induced oxidative damage to pUC19 DNA by gel electrophoresis and antineoplastic activity was evaluated on Ehrlich ascites carcinoma (EAC) bearing Swiss albino mice by evaluating percentage inhibition of cell growth, morphological changes of EAC cells and hematological parameters of the mice. The isolation was carried out by column chromatography and structure was revealed by 1H-NMR and 13C NMR. The result shows that, the isolated compound was identified as myricetin 4'-methoxy-3-O-α-l-rhamnopyranoside based on previously reported data. The isolated flavone effectively inhibited AAPH-induced oxidative damage to DNA; because it could inhibit the formation of circular and linear forms of the DNA. In anti-proliferative assay, 76% growth inhibition of EAC cells was observed as compare to the control mice (p<0.05) at a dose 100 mg/kg body weight. Thus the isolated flavone showed great importance as a possible therapeutic agent in preventing oxidative damage to DNA and the chronic diseases caused by such DNA damage, and can also become important in cancer chemotherapy. 相似文献
90.
Almost all of the methodologies developed to date to assay the potential mutagenicity of chemical substances are based on detection of altered phenotypic traits. The alternative approach of directly screening the whole genome for mutations is not feasible because of the logistics of carrying out mass sequencing of genes. Here we describe a novel and highly sensitive mutation assay, which we term the 'genome profiling-based mutation assay' (GPMA) that directly detects mutations generated in genomic DNA. We used GPMA to detect mutations caused by known mutagens such as AF2 and ethidium bromide even at concentrations of 30 ppb. The number of mutations detected was dependent on the number of generations in culture and the concentrations of the mutagens. Almost complete agreement was observed between GPMA and the Ames test in the discrimination of mutagens (63 out of 64). Owing to the high sensitivity of GPMA, the effects of long-term and low-dose exposures and the influence of chemicals of low solubility can also be screened. Thus, genotype-based GPMA can complement the Ames test, which is the standard technology in this field and is based on phenotypic traits. 相似文献