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71.
Abdul Wahab Rizwan Ul Haq Aftab Ahmed Rafeeq Alam Khan Mohsin Raza 《Phytotherapy research : PTR》2009,23(2):153-158
The purpose of this study was to investigate the anticonvulsant activity of the volatile oil of nutmeg, the dried seed kernel of Myristica fragrans Houtt, using well‐established animal seizure models and to evaluate its potential for acute toxicity and acute neurotoxicity. The volatile oil of nutmeg (nutmeg oil) was tested for its effects in maximal electroshock, subcutaneous pentylenetetrazole, strychnine and bicuculline seizure tests. All the experiments were performed at the time of peak effect of nutmeg oil. Nutmeg oil showed a rapid onset of action and short duration of anticonvulsant effect. It was found to possess significant anticonvulsant activity against electroshock‐induced hind limb tonic extension. It exhibited dose dependent anticonvulsant activity against pentylenetetrazole‐induced tonic seizures. It delayed the onset of hind limb tonic extensor jerks induced by strychnine. It was anticonvulsant at lower doses, whereas weak proconvulsant at a higher dose against pentylenetetrazole and bicuculline induced clonic seizures. Nutmeg oil was found to possess wide therapeutic margin, as it did not induce motor impairment when tested up to 600 µL/kg in the inverted screen acute neurotoxicity test. Furthermore, the LD50 (2150 µL/kg) value was much higher than its anticonvulsant doses (50–300 µL/kg). The results indicate that nutmeg oil may be effective against grand mal and partial seizures, as it prevents seizure spread in a set of established animal models. Slight potentiation of clonic seizure activity limits its use for the treatment of myoclonic and absence seizures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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73.
Hydrophobic clinoptilolite (CP) was successfully synthesized via a silanization method using methyltriethoxysilane (MTS) or diethoxydimethylsilane (DMTS) as silane coupling agents. The structural and textural properties of the resultant hydrophobic CP were characterized using various methods. The effect of the amount of MTS or DMTS additive on the induction (nucleation) and growth of CP were also investigated, and the apparent activation energy values for induction and growth periods were calculated, suggesting that the induction period is kinetically controlled, while the rapid growth process is thermodynamically controlled. Meanwhile, DMTS modification enhanced the hydrophobicity of CP compared with its MTS-modified counterpart and pure CP. Finally, various ZnO-supported CPs were used as photocatalysts for the removal of crystal violet from aqueous solution, demonstrating that ZnO/hydrophobic CP has the largest adsorption capacity and best removal performance. These results suggest that hydrophobic CP, as an adsorbent or support, has the most potential for applications in separation and catalysis.One-step synthesis of hydrophobic CPs was demonstrated, in which the kinetically-controlled induction period and thermodynamically-based rapid growth process were elucidated. 相似文献
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75.
Arsalan Raza Imran Khan Rana Faisal Tufail Jana Frankovska Muhammad Umar Mushtaq Abdellatif Salmi Youssef Ahmed Awad Muhammad Faisal Javed 《Materials》2022,15(15)
To enhance the moisture damage performance of hot mix asphalt (HMA), treating the aggregate surface with a suitable additive was a more convenient approach. In this research, two types of aggregate modifiers were used to study the effect of moisture damage on HMA. Three different aggregate sources were selected based on their abundance of use in HMA. To study the impact of these aggregate modifiers on moisture susceptibility of HMA, the indirect tensile strength test and indirect tensile modulus test were used as the performance tests. Moisture conditioning of specimens was carried out to simulate the effect of moisture on HMA. The prepared samples’ tensile strength ratio (TSR) and stiffness modulus (Sm) results indicated a decrease in the strength of the HMA after moisture conditioning. After treating the aggregate surface with additives, an improvement was seen in dry and wet strength and stiffness. Moreover, an increasing trend was observed for both additives. The correlation between TSR and strength loss reveals a strong correlation (R2 = 0.7219). Also, the two additives indicate increased wettability of asphalt binder over aggregate, thus improving the adhesion between aggregate and asphalt binder. 相似文献
76.
Silveira R Jainer AK Singh R 《Journal of the American Academy of Child and Adolescent Psychiatry》2002,41(11):1270; author reply 1271
77.
Muhammad Ummear Raza Turan Tufan Yan Wang Christopher Hill Meng-Yang Zhu 《Neurotoxicity research》2016,30(2):251-267
Human cells are exposed to exogenous insults and continuous production of different metabolites. These insults and unwanted metabolic products might interfere with the stability of genomic DNA. Recently, many studies have demonstrated that different psychiatric disorders show substantially high levels of oxidative DNA damage in the brain accompanied with morphological and functional alterations. It reveals that damaged genomic DNA may contribute to the pathophysiology of these mental illnesses. In this article, we review the roles of oxidative damage and reduced antioxidant ability in some vastly studied psychiatric disorders and emphasize the inclusion of treatment options involving DNA repair. In addition, while most currently used antidepressants are based on the manipulation of the neurotransmitter regulation in managing different mental abnormalities, they are able to prevent or reverse neurotoxin-induced DNA damage. Therefore, it may be plausible to target on genomic DNA alterations for psychiatric therapies, which is of pivotal importance for future antipsychiatric drug development. 相似文献
78.
Dynamic contrast material-enhanced magnetic resonance (MR) imaging has emerged as a valuable tool in evaluation of women who have undergone lumpectomy and whole-breast radiation therapy for breast cancer. Early diagnosis of local recurrence by means of close clinical and imaging follow-up is an important component of a breast-conserving strategy, as it may improve survival. In the post-breast conservation therapy (BCT) breast, resolving edema, fat necrosis, a small focal area of non-masslike enhancement (NMLE), and thin linear NMLE at the lumpectomy site can all be expected findings. In contrast, masslike enhancement or NMLE of ductal or segmental distribution can indicate recurrence. Therefore, at MR imaging of the post-BCT breast, it is important to identify lesions that are benign or appropriate for short-interval imaging surveillance to minimize unnecessary intervention, as well as to discern suspicious lesions and optimize the diagnosis of recurrence. 相似文献
79.
Kadriye Agan Nazire Afsar Ipek Midi Onder Us Sevinc Aktan Canan Aykut-Bingol 《Epilepsy & behavior : E&B》2009,14(4):651-654
Refractory status epilepticus (RSE) is known to constitute approximately 10–50% of all cases of status epilepticus (SE) and is associated with significant morbidity and mortality. In the present study, data from a prospectively collected SE database were analyzed. Patients with RSE (defined as a SE episode requiring a second line of intravenous treatment following intravenous phenytoin) were compared with patients with nonrefractory SE (NRSE); 290 episodes of SE were identified, of which 108 (38%) were defined as RSE. Univariate analysis revealed that age, female gender, SE type, SE duration, and acute etiology were associated with refractoriness, whereas electroencephalographic patterns were not. Nonconvulsive SE, which is probably associated with delays in treatment initiation, was a predictor of RSE, although it was not retained as a predictor in multivariate analysis. In the latter analysis, female gender (odds ratio: 1.815, 95% CI: 1.053–3.126) and acute etiology (odds ratio: 0.619, 95% CI: 0.429–0.894) were shown to be the only significant independent predictors of refractoriness. 相似文献
80.