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81.
Waqas Khan Shujaul Mulk Khan Habib Ahmad Abdulaziz A. Alqarawi Ghulam Mujtaba Shah Manzoor Hussain E.F. Abd_Allah 《Saudi Journal of Biological Sciences》2018,25(1):94-100
The life form and leaf size spectra of plant species of the Thandiani forests, district Abbottabad, were studied during the summer of 2013. These forests host 252 plant species of 97 families. Biological spectra showed that Hemicryptophytes (80 spp., 31.74%) were dominant followed by Megaphanerophytes (51 spp., 20.24%), Therophytes (49 spp., 19.44%) and Nanophanerophytes (45 spp., 17.86). Hemicryptophytes are the indicators of cold temperate vegetation. At the lower elevations, Megaphanerophytes and Nanophanerophytes were dominant which confirm trees as dominant habit form due to high soil depth, moisture and temperature factors. Data on Leaf spectra in the area showed that Microphyllous (88 spp., 34.92%) species were dominant followed by Leptophyllous (74 spp., 29.36%) and Nanophyllous (60 spp., 23.80%). The Microphyllous plants again are the indicator of cold temperate zone as the area is situated at an elevation of 1191–2626 m. Similarly, Nanophylls were dominant at lower elevations. Data on family importance values and diversity among various communities were also recorded. Life form and Leaf spectra studies could be used to understand the micro climatic variation of the region. 相似文献
82.
Liam Chung Erik Thiele Orberg Abby L. Geis June L. Chan Kai Fu Christina E. DeStefano Shields Christine M. Dejea Payam Fathi Jie Chen Benjamin B. Finard Ada J. Tam Florencia McAllister Hongni Fan Xinqun Wu Sudipto Ganguly Andriana Lebid Paul Metz Sara W. Van Meerbeke Franck Housseau 《Cell host & microbe》2018,23(2):203-214.e5
83.
84.
Ali Shafaqat Rizwan Muhammad Waqas Abdul Hussain Muhammad Bilal Hussain Afzal Liu Shiliang Alqarawi Abdulaziz A. Hashem Abeer Abd_Allah Elsayed Fathi 《Journal of Plant Growth Regulation》2018,37(4):1357-1367
Journal of Plant Growth Regulation - Rapid industrialization is potentially contaminating the environment. Tannery is one of the industries producing very high amount of effluents, having a... 相似文献
85.
A method is described which demonstrates nuclei, elastic fibers, red blood cells, collagen and fibrin. Nuclei and elastic fibers are stained by a modified Verhoeff's elastic tissue stain which was previously developed and used in the elastic-Masson combination. Both early fibrin and red blood cells are shown by lissamine fast yellow. Mature fibrin, some types of collagen and other cytoplasmic changes are stained by a combination of acid fuchsin, Biebrich scarlet and ponceau 2R, while old fibrin is demonstrated by the collagen stain. This method takes about 1 hr to perform and has the added advantage that several entities are clearly shown in a single slide. 相似文献
86.
Nabil M. Elsayed Mohammad G. Mustafa Allen D. Hacker Klaus Kuehn Gerhard N. Schrauzer 《Biological trace element research》1984,6(3):249-261
We fed female strain A/St mice selenium (Se) test diets containing either no Se (?Se) or 1 ppm Se (+Se) for 11 wk. Both diets contained 55 ppm vitamin E. We then exposed three groups of mice from each dietary regimen to either 0.8 ppm (1568 μg/m3) O3 (low-level) continuously for 5 d, 10.0 ppm (19,600 μg/m3) O3 (high-level) for 12 h, or filtered room air, where the latter served as a control for both O3 exposures. After O3 exposures we analyzed the lungs for various physical and biochemical parameters, and compared the results to those obtained from the air controls. The results showed that the difference in dietary Se intake produced an eightfold difference in Se content and a three-fold difference in glutathione peroxidase (GP) activity in the lung, but few changes in other lung parameters. With low-level O3 exposure, NADPH production increased significantly in +Se mice, but did not change in ?Se mice. With high-level O3 exposure we observed comparable effects for both dietary regimens, including animal mortality, which was 24% for ?Se and 14% for +Se mice. Thus, it seems that diminished GP activity resulting from Se deficiency and the ensuing lack of increase in NADPH production were poorly correlated with mouse tolerance to O3. The lung Se content increased in both dietary regimens after O3 exposure, but the increase was greater after high-level O3 exposure. This suggests a “mobilization” of Se to the lung under O3 stress. It is possible that such a mobilization contributes to the lung reserve of antioxidants, and hence the comparable mortality in both dietary Se regimens. 相似文献
87.
The quantitative estimation of total dopamine (DA), noradrenaline (NE), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content in the whole brain tissue of normal Nile grass rat, Arvicanthis niloticus, gives and average of 631 +/- 12 ng DA/g, 366 +/- 12 ng NE/g, 617 +/- 15 ng 5-HT/g and 431 +/- 10 ng 5-HIAA/g fresh brain tissue. The effect of barbitone sodium and thiopental sodium on the total DA, NE, 5-HT and 5-HIAA content in the brain tissue of the Nile grass rat, Arvicanthis niloticus, was studied. The total DA, NE, 5-HT and 5-HIAA contents were determined 5 hr after i.p. injection of different doses of barbitone sodium (20, 40 and 80 mg/ml/100 g body wt) and thiopental sodium (5, 10 and 20 mg/ml/100 g body wt). The effect of different time intervals (1, 10, 30 min, 1, 2.5, 5, 8, 16, 24 and 48 hr) on the total brain DA, NE, 5-HT and 5-HIAA content was investigated after i.p. injection of 40 mg of barbitone sodium and 10 mg of thiopental sodium/ml/100 g body wt. Both barbitone sodium and thiopental sodium caused an increase in DA, NE and 5-HT content and a decrease in 5-HIAA content in the brain tissue of Arvicanthis niloticus. The increase in the whole brain contents of DA, NE and 5-HT after the administration of barbitone sodium and thiopental sodium may be due either to inhibition of transmitter release by an action at the monoamine nerve terminal or to effects causing a decrease in nerve impulse flow. On the other hand, the decrease in 5-HIAA may be due to the decrease in the turnover of 5-HT. 相似文献
88.
Eman M. Dokla Amr H. Mahmoud Mohamed S. A. Elsayed Ahmed H. El-Khatib Michael W. Linscheid Khaled A. Abouzid 《PloS one》2012,7(11)
This study provides a comprehensive computational procedure for the discovery of novel urea-based antineoplastic kinase inhibitors while focusing on diversification of both chemotype and selectivity pattern. It presents a systematic structural analysis of the different binding motifs of urea-based kinase inhibitors and the corresponding configurations of the kinase enzymes. The computational model depends on simultaneous application of two protocols. The first protocol applies multiple consecutive validated virtual screening filters including SMARTS, support vector-machine model (ROC = 0.98), Bayesian model (ROC = 0.86) and structure-based pharmacophore filters based on urea-based kinase inhibitors complexes retrieved from literature. This is followed by hits profiling against different extended electron distribution (XED) based field templates representing different kinase targets. The second protocol enables cancericidal activity verification by using the algorithm of feature trees (Ftrees) similarity searching against NCI database. Being a proof-of-concept study, this combined procedure was experimentally validated by its utilization in developing a novel series of urea-based derivatives of strong anticancer activity. This new series is based on 3-benzylbenzo[d]thiazol-2(3H)-one scaffold which has interesting chemical feasibility and wide diversification capability. Antineoplastic activity of this series was assayed in vitro against NCI 60 tumor-cell lines showing very strong inhibition of GI50 as low as 0.9 uM. Additionally, its mechanism was unleashed using KINEX™ protein kinase microarray-based small molecule inhibitor profiling platform and cell cycle analysis showing a peculiar selectivity pattern against Zap70, c-src, Mink1, csk and MeKK2 kinases. Interestingly, it showed activity on syk kinase confirming the recent studies finding of the high activity of diphenyl urea containing compounds against this kinase. Allover, the new series, which is based on a new kinase scaffold with interesting chemical diversification capabilities, showed that it exhibits its “emergent” properties by perturbing multiple unexplored kinase pathways. 相似文献
89.
Plasmonics - In this work, a transparent metasurface absorber/emitter (TMAE) is proposed based on the transparent metal of indium tin oxide (ITO) and substrate layer consisting of (ZnS). This... 相似文献
90.
Ansermot N Fathi M Veuthey JL Desmeules J Hochstrasser D Rudaz S 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,857(1):92-99
As a potential alternative to cyclosporine A (CsA) monitoring in whole blood, a sensitive and selective method was developed for quantifying this immunosuppressive drug in human peripheral blood mononuclear cells (PBMCs) by liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS). PBMCs were isolated from whole blood by density gradient centrifugation. After purification, cell counts were performed to express CsA amounts per single cell. The pelleted cells were then lysed and CsA was extracted with methanol (MeOH) containing 27-demethoxy-sirolimus as internal standard. After evaporation of the supernatant under nitrogen, the residue was reconstituted in MeOH, further diluted with water and injected onto a column-switching unit. On-line solid-phase extraction was performed using a C8 column with an acidic aqueous mobile phase containing 5% MeOH. The analytes were transferred in the back-flush mode on a C18 column with 65% MeOH and the chromatographic separation performed with a MeOH gradient (65-90%). The detection was carried out with a single quadrupole analyzer and the sodium adducts [M+Na](+) were monitored for quantification. This sensitive method was fully validated in the range of 5-400 ng/mL. This allowed the measurement of very small CsA amounts present in cells up to 0.5 fg/PBMC in clinical samples. Trueness (95.0-113.2%), repeatability (5.1-9.9%) and intermediate precision (7.0-14.7%) were found to be satisfactory. This method represents a new potential tool for therapeutic drug monitoring of CsA and could be used in clinical conditions if the utility of intracellular measurements is confirmed in prospective clinical trials. 相似文献