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61.
Algamal Zakariya Yahya Lee Muhammad Hisyam 《Advances in Data Analysis and Classification》2019,13(3):753-771
Advances in Data Analysis and Classification - The common issues of high-dimensional gene expression data are that many of the genes may not be relevant, and there exists a high correlation among... 相似文献
62.
Hanif MA Al-Maskri AY Al-Mahruqi ZM Al-sabahi JN Al-Azkawi A Al-Maskari MY 《Natural product communications》2011,6(10):1451-1454
Three wild Omani plants, Moringa peregrina, Acacia nilotica and Rhazya stricta, were selected for the present study. Na, K and Ca contents were determined using flame photometric analysis. M. peregrina seeds (22.5 mg/g) and pods (27.7 mg/g) had higher Na contents than A. nilotica (0.33 mg/g) and R. stricta (0.30 mg/g), whereas the K and Ca contents of R. stricta were significantly higher than those of the other two plants. The protein content was lowest in R. stricta (9.8%) and highest in M peregrina seeds (21.0%). The highest total phenolic contents (TPC) were found in M. peregrina seeds (350.3 mg/g) and the lowest in A. nilotica (66.1 mg/g). The major component of M. peregrina seed oil was oleic acid (74.7%). Gas chromatographic-mass spectrometric analysis (GC-MS) revealed that octadecanal (30.9%) was the major compound in A. nilotica. The presence of various phenolics and flavonoids in M. peregrina, A. nilotica and R. stricta were confirmed by high performance liquid chromatography (HPLC). 相似文献
63.
Faiz Ali Khan Gowhar Ali Khista Rahman Yahya Khan Muhammad Ayaz Osama F. Mosa Asif Nawaz Syed Shams ul Hassan Simona Bungau 《Molecules (Basel, Switzerland)》2022,27(17)
The current work examined the pharmacological potential of a selected flavanone derivative 2-hydroxyflavanone as a promising remedy for the treatment and management of pain. The selected flavanone derivative (2-HF) was evaluated for its analgesic and anti-inflammatory potentials following standard pharmacological protocols including hot plate, acetic acid-induced writhing and tail immersion tests. Naloxone and pentylenetetrazol were used to evaluate the potential implication of GABAergic and opioidergic mechanisms. The anti-inflammatory potential of 2-HF was confirmed using carrageenan-, serotonin- and histamine-induced paw edema models as well as a xylene-induced ear edema model. Furthermore, the anti-neuropathic potential of 2-HF was tested using a cisplatin-induced neuropathic pain model. Our sample, at the tested concentrations of 15, 30 and 45 mg kg−1, showed considerable analgesic, anti-inflammatory effects, as well as efficacy against neuropathic pain. Naloxone and pentylenetetrazol at 1 and 15 mg kg−1 antagonized the anti-nociceptive activities of 2-hydroxyflavanone indicating the involvement of opioidergic and GABAergic mechanisms. In the static allodynia model, combination of gabapentin 75 mg kg−1 with 2-HF at 15, 30, 45 mg kg−1 doses exhibited considerable efficacy. In cold allodynia, 2-hydroxyflavanone, at doses of 15, 30 and 45 mg kg−1 and in combination with gabapentin (75 mg kg−1), demonstrated prominent anti-allodynic effects. The paw withdrawal latency was considerably increased in gabapentin + cisplatin treated groups. Moreover, cisplatin + 2-hydroxyflavanone 15, 30, 45 mg kg−1 showed increases in paw withdrawal latency. Likewise, considerable efficacy was observed for 2-hydroxyflavanone in thermal hyperalgesia and dynamic allodynia models. Our findings suggest that 2-hydroxyflavanone is a potential remedy for pain syndrome, possibly mediated through opioidergic and GABAergic mechanisms. 相似文献
64.
Kailey A. Wyman Adel S. Girgis Pragnakiran S. Surapaneni Jade M. Moore Noura M. Abo Shama Sara H. Mahmoud Ahmed Mostafa Reham F. Barghash Zou Juan Radha D. Dobaria Ahmad J. Almalki Tarek S. Ibrahim Siva S. Panda 《Molecules (Basel, Switzerland)》2022,27(18)
We synthesized a set of small molecules using a molecular hybridization approach with good yields. The antiviral properties of the synthesized conjugates against the SAR-CoV-2 virus were investigated and their cytotoxicity was also determined. Among all the synthesized conjugates, compound 9f showed potential against SARS-CoV-2 and low cytotoxicity. The conjugates’ selectivity indexes (SIs) were determined to correlate the antiviral properties and cytotoxicity. The observed biological data were further validated using computational studies. 相似文献
65.
Kamal Y. Thajudeen Yahya I. Asiri Shahana Salam Shabeer Ali Thorakkattil Mohamed Rahamathulla Ilyas Uoorakkottil 《Molecules (Basel, Switzerland)》2022,27(19)
The objectives of this study were to optimize and quantify the maximum percentage yield of eupalitin-3-O-β-D-galactopyranosidefrom Boerhavia diffusa leaves using response surface methodology (RSM), as well as to demonstrate the hepatoprotective benefits of the bioactive compound. The Box–Behnken experimental design was utilized to optimize the eupalitin-3-O-β-D-galactopyranoside extraction procedure, which also looked at the extraction duration, temperature, and solvent concentration as independent variables. Boerhaviadiffusa leaves were extracted, and n-hexane, chloroform, ethyl acetate, and water were used to fractionate the dried extracts. The dried ethyl acetate fraction was thoroughly mixed in hot methanol and stored overnight in the refrigerator. The cold methanol was filtered, the solid was separated, and hot methanol was used many times to re-crystallize the solid to obtain pure eupalitin-3-O-β-D-galactopyranoside (0.1578% w/w). The proposed HPTLC method for the validation and quantification of eupalitin-3-O-β-D-galactopyranosidewassuccessfully validated and developed. The linearity (R2 = 0.994), detection limit (30 ng), and quantification limit (100 ng) of the method, as well as its range (100–5000 ng), inter and intraday precision (0.67% and 0.991% RSD), specificity, and accuracy (99.78% RSD), were all validated as satisfactory. The separation of the eupalitin-3-O-β-D-galactopyranoside band was achieved on an HPTLC plate using toluene:acetone:water (5:15:1 v/v) as a developing system. The Box–Behnken statistical design was used to determine the best optimization method, which was found to be extraction time (90 min), temperature (45 °C), and solvent ratio (80% methanol in water v/v) for eupalitin-3-O-β-D-galactopyranoside. Standard silymarin ranged from 80.2% at 100 µg/mL to 86.94% at 500 µg/mL in terms of significant high hepatoprotection (cell induced with carbon tetrachloride 0.1%), whereas isolated eupalitin-3-O-β-D-galactopyranoside ranged from 62.62% at 500 µg/mL to 70.23% at 1000 µg/mL. More recently, it is a source of structurally unique flavonoid compounds that may offer opportunities for developing novel semi-synthetic molecules. 相似文献
66.
R. A. Brown Razak Abd. Samad Bin Yahya 《Journal of Polymer Science.Polymer Physics》1985,23(3):451-459
Measurements of thermal diffusivities of peroxide-cured and sulfur-cured rubbers, over the range 0–100°C and 0–75 phr of carbon, are described. They are based on the asymptotic time dependences of heating and cooling curves, recorded following quenching of the samples into baths at various temperatures. The diffusivities are shown to depend linearly on both temperature and carbon content, to reasonable accuracies over the ranges studied. Some theory bearing on measurement techniques is presented. 相似文献
67.
68.
Grafted natural rubber-based polymer electrolytes: ATR-FTIR and conductivity studies 总被引:2,自引:0,他引:2
Attenuated total reflectance–Fourier transformed infrared spectroscopy measurement is employed to study the interactions between
the components of 30% methyl-grafted natural rubber (MG30), lithium trifluromethanesulfonate (LiCF3SO3 or LiTF), and propylene carbonate (PC). Vibrational spectra data of LiTF reveals that the νs(SO3) at 1,045 cm−1, δs(CF3) at 777 cm−1, and C=O stretching mode at 1,728 cm−1 for MG30 have shifted to lower wave numbers in MG30–LiTF complexes indicating that complexation has occurred between MG30
and LiTF. The solvation of lithium ion is manifested in Li+ ← O=C interaction as shown by the downshifting and upshifting of C=O mode at 1,788 to 1,775 cm−1 and νas(SO3) at 1,250 to 1258 cm−1, respectively, in LiTF–PC electrolytes. There is no experimental evidence of the interaction between MG30 and PC. Competition
between MG30 and PC on associating with lithium ion is studied, and the studies show that the interaction between MG30–LiTF
is stronger than that of the PC–LiTF in plasticized polymer–salt complexes. The effect of PC on the ionic conductivity of
the MG30–LiTF system is explained in terms of the polymer, plasticizer, and salt interactions. The temperature dependence
of conductivity of the polymer films obeys the Vogel–Tamman–Fulcher relation. Values of conductivity and activation energy
of the MG30-based polymer electrolyte systems are presented and discussed. 相似文献
69.
Conductivity studies of plasticized anhydrous PEO-KOH alkaline solid polymer electrolyte 总被引:1,自引:0,他引:1
Polyethylene oxide (PEO)–potassium hydroxide (KOH)-based alkaline solid polymer electrolyte films have been prepared by using
methanol as solvent. The highest room temperature ionic conductivity of (2.1 ± 0.5) × 10−8 S cm−1 was achieved for the composition of 70 wt% PEO:30 wt% KOH. The addition of plasticizer, ethylene carbonate, propylene carbonate,
or polyethylene glycol to the highest conductivity of PEO–KOH system helps to increase the ambient ionic conductivity to the
order of 10−6–10−4 S cm−1. The log σ vs 1/T plot of PEO–KOH showed a small conductivity decrease at 50–60 °C range. The small decrease and the hysteresis that occur
during the heating–cooling cycle was overcome by the presence of the plasticizer. X-ray diffraction observation supports the
conductivity results. 相似文献
70.
In this work, the effect of magnetic field, rotation and initial stress on peristaltic motion of micropolar fluid in a circular cylindrical flexible tube with viscoelastic or elastic wall properties has been considered. Runge–Kutta technique are used. Runge–Kutta method is developed to solve the governing equations of motion resulting from a perturbation technique for small values of amplitude ratio. The time mean axial velocity profiles are presented for the case of free pumping and analyzed to observe the influence of wall properties, magnetic field, rotation and initial stress for various values of micropolar fluid parameters. In the case of viscoelastic wall, the effect of viscous damping on mean flow reversal at the boundary is seen. The numerical results of the time mean velocity profile are discussed in detail for homogeneous fluid under the effect of wall properties, magnetic field, initial stress and rotation for different cases by figures. The results indicate that the effect of wall properties, rotation, initial stress and magnetic field are very pronounced. Numerical results are given and illustrated graphically. 相似文献