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71.
Fluconazole resistance is becoming an important clinical concern. We studied the in vitro effects of cinnamaldehyde against 18 fluconazole-resistant Candida isolates. MIC90 of cinnamaldehyde against different Candida isolates ranged 100–500 μg/ml. Growth and sensitivity of the organisms were significantly affected by cinnamaldehyde at different concentrations. The rapid irreversible action of this compound on fungal cells suggested membrane-located targets for its action. Insight studies to mechanism suggested that cinnamaldehyde exerts its antifungal activity by targeting sterol biosynthesis and plasma membrane ATPase activity. Inhibition of H+-ATPase leads to intracellular acidification and cell death. Toxicity against H9c2 rat cardiac myoblasts was studied to exclude the possibility of further associated cytotoxicity. The observed selectively fungicidal characteristics against fluconazole-resistant Candida isolates signify a promising candidature of this essential oil as an antifungal agent in treatments for candidosis. 相似文献
72.
Khan I Nisar M Ahmad M Shah H Iqbal Z Saeed M Halimi SM Kaleem WA Qayum M Aman A Abdullah SM 《Fitoterapia》2011,82(2):276-281
A new taxoid Taxawallin I (1) along with two known taxoids (2-3) were isolated from methanolic bark extract of Taxus wallichiana Zucc. Structural characterization was confirmed by mass and NMR spectral techniques. Taxawallin I exhibited significant in-vitro anticancer activity against HepG2, A498, NCI-H226 and MDR 2780AD cancer lines. Tubulin binding assay was performed to assess its tubulin binding activity. Molecular docking analysis was performed to study the potential binding mode inside the taxol binding site of β-tubulin. 相似文献
73.
Md. Habibur Rahman Md. Abu Sayed Arfin Khan Bishwajit Roy Most. Jannatul Fardusi 《林业研究》2011,22(4):551-559
A study was conducted at two-biodiversity conservation areas of Northeastern Bangladesh (a part of Sylhet Forest Division)
to assess the species composition, diversity and density of natural regeneration of tree species both indigenous and exotic
species. Data were collected by stratified random quadrate method during January 2010 to July 2010. Totally 200 circular plots
of 2 m×2 m in size had 5 different habitat types of plants namely; forest, roadside, homestead (surrounding forest dwellers
house), fallow land and others (canals, streams and tea gardens side), which included a total of 55 regenerating species belonging
to 28 families. Meliaceae is the dominant family and shows the highest family importance value (26.3), having six species,
followed by Moraceae (24.24). Among the five habitat types, forest (43 species) possess the highest number of species, followed
by roadside (23 species). Total 15 exotic species among 9 families and 40 indigenous species with 24 families were recorded.
For exotic species, Tectona grandis possess the highest relative density (11.7%) and relative frequency (10.5%); Senna siamea had highest relative abundance (7.83%). In case of indigenous species, Chickrassia tabularis possess the highest relative density (4.23%) and relative frequency (4%); Dipterocarpus turbinatus had the highest relative abundance (3.92%). Tectona grandis (29.66) and Chickrassia tabularis (10.8) had the highest IVI for exotic and indigenous species respectively. Different diversity indices such as Shanon-Winner
diversity index, species diversity index, species richness index, species evenness index, Simpson index and species dominance
index, etc. were applied to quantify definite diversity. The regeneration of species associated with low levels of disturbance
was in the exotic species. Study suggests that proper protection from human disturbances and scientific management of natural
regeneration of two-study forests may lead a rich biodiversity site in the country. 相似文献
74.
Shahbaz Khan Muhammad Nadeem Asghar Tariq Rana 《Water, air, and soil pollution》2007,182(1-4):131-148
Automated synoptic weather typing and robust orthogonal stepwise regression analysis (via principal components analysis) were applied together to develop within-weather-type air pollution prediction models for a variety of pollutants (specifically, carbon monoxide – CO, nitrogen dioxide – NO2, ozone – O3, sulphur dioxide – SO2, and suspended particles – SP) for the period 1974–2000 in south-central Canada. The SAS robust regression procedure was used to limit the influence of outliers on air pollution prediction algorithms. Six-hourly Environment Canada surface observed meteorological data and 6-hourly US National Centers for Environmental Prediction (NCEP) reanalysis data of various weather elements were used in the analysis. The models were developed using two-thirds of the total years for meteorological and air pollution data; the remaining one-third (randomly selected) was used for model validation. Robust stepwise regression analysis was performed to analytically determine the meteorological variables that might be used to predict air pollution concentrations. There was a significant correlation between observed daily mean air pollution concentrations and model predictions. About 20, 50, and 80% of the 80 prediction models across the study area possessed R 2 values ≥ 0.7, 0.6, and 0.5, respectively. The results of model validation were similar to those of model development, with slightly smaller model R 2 values. 相似文献
75.
Shahbaz Khan Hafeez ur Rehman Muhammad Ashfaq Wahid Muhammad Farrukh Saleem Mumtaz Akhtar Cheema Shahzad Maqsood Ahmed Basra 《Journal of plant nutrition》2016,39(12):1681-1687
The impact of soil (1, 2 kg ha?1) and foliar (100, 200 mg L?1) boron (B) with control (no B) was evaluated on phenology and yield formation of Camelina each applied at stem elongation and flowering stages. Foliar (200 mg L?1) or soil B (2 kg ha?1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L?1) or soil applied (2 kg ha?1) B seems promising to improve seed and oil yield, harvest index of Camelina sativa under B deficient condition. 相似文献
76.
M. Shahadat Hossain Khan Tadao Wagatsuma Afrin Akhter Idupulapati M. Rao 《Journal of plant nutrition》2015,38(13):1973-1983
Nutrient deficiencies are often an additional growth-limiting factor in tropical acid soils. Considering the potential interactions between Al stress and low-nutrient stress, differences among rice cultivars for Al tolerance, low-nutrient tolerance, and combined stress tolerance were investigated. The main objective of this study was to identify the predominant growth-limiting factor in tropical acid soils. Tolerance to low nutrient stress and combined stress did not show any relationship with aluminum (Al) tolerance indicating that these stress factors act independently. Al-tolerant cv. Rikuu-132 was tolerant to combined stress. Conversely, highly Al-sensitive cv. BR34 was most tolerant to combined and low nutrient stress. Combined stress tolerance of shoot was positively correlated with calcium (Ca) content of shoot. The results indicate that Al tolerance alone is not adequate for superior performance on most acid soils. Tolerance to combined stress factors would be needed to improve productivity of rice on low fertility acid soils. 相似文献
77.
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80.
Cytokinins: permissive role in seed germination 总被引:14,自引:0,他引:14
A A Khan 《Science (New York, N.Y.)》1971,171(974):853-859