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181.
Leila Pirmoradi Mohammad Taghi Mohammadi Akbar Safaei Fakhardin Mesbah Gholam Abbas Dehghani 《Iranian Biomedical Journal》2014,18(3):173-180
Background: Data shows vanadium protects pancreatic beta cells (BC) from diabetic animals. Whether this effect is direct or through the relief of glucose toxicity is not clear. This study evaluated the potential effect of oral vanadyl sulfate (vanadium) on glycemic status and pancreatic BC of normal and diabetic rats. Methods: Rats were divided into five groups of normal and diabetic. Diabetes was induced with streptozocin (40 mg/kg, i.v.). Normal rats used water (CN) or vanadium (1 mg/ml VOSO4, VTN). Diabetic rats used water (CD), water plus daily neutral protamine Hagedorn insulin injection (80 U/kg, ITD) or vanadium (VTD). Blood samples were taken for blood glucose (BG, mg/dL) and insulin (ng/dL) measurements. After two months, the pancreata of sacrificed rats were prepared for islet staining. Results: Pre-treated normal BG was 88 ± 2, and diabetic BG was 395 ± 9. The final BG in CD, VTD, and ITD was 509 ± 22, 138 ± 14, and 141 ± 14, respectively. Insulin in VTN (0.75 ± 0.01) and VTD (0.78 ± 0.01) was similar, higher than CD (0.51 ± 0.07) but lower than CN (2.51 ± 0.02). VTN islets compared to CN had larger size and denser central core insulin immunoreactivity with plentiful BC. CD and ITD islets were atrophied and had scattered insulin immunoreactivity spots and low BC mass. VTD islets were almost similar to CN. Conclusion: Besides insulin-like activity, vanadium protected pancreatic islet BC, and the relief of glucose toxicity happening with vanadium had a little role in this action. Key Words: Vanadium, Rats, Diabetes, Protection, Beta cells 相似文献
182.
Hideo?NakasoneEmail author Muhammad?Akhtar?Abbas Hisao?Kuroda 《Paddy and Water Environment》2004,2(3):115-124
Our understanding of nitrogen transformation in paddy fields or wetlands is limited due to the complex interactions between soil, water, and biomass. Therefore, we studied transformation patterns resulting from the oxic level in the soil, and studied saturated (anoxic) and unsaturated (oxic) flow conditions. We present a model designed to predict concentrations of nitrate and ammonium at several soil depths resulting from the processes of nitrification, denitrification, and ammonification. Model equations were obtained that describe NO3-N and NH4-N concentrations in terms of position, rate constant, and average flow velocity. Although many parameters were included in the model equations, some were determined from the literature and others were derived from experiments. A sensitivity analysis of the rate coefficients for NO3-N and NH4-N revealed that they are extremely sensitive to denitrification and ammonification respectively. Experimental results show that there were large differences in the transformations of NO3-N and NH4-N, the water pressure distributions, and the oxygen reduction potentials (ORP) between saturated and unsaturated pore water flow conditions. The performance of the model for sequential transformations during the transport of NO3-N is well documented under both saturated and unsaturated flow conditions. 相似文献
183.
Mohsen Shanbeh Fatemeh Ataee Abbas Tabibi Sedigheh Khanmohammadi 《Fibers and Polymers》2014,15(2):373-381
Set marks are fabric defects in weft direction which are caused by an interruption of the weaving process. In this study, based on one-quarter fractional factorial design, among eight parameters of weaving machine, i.e. horizontal and vertical position of back rest roller, horizontal position of warp stop motion, shed crossing degree, shed crossing point position, warp tension, stoppage position of machine, and stoppage time, four most effective parameters was determined. These parameters were stoppage position of machine, vertical position of back rest roller, shed crossing point, and horizontal position of warp stop motion. Then using full factorial design effectiveness of these parameters was evaluated statistically at 99 % confidence level and effect of them on set mark studied in detail. Statistical evaluations showed that the stoppage position of machine was the most effective parameters on intensity of set mark of multifilament polyester fabric. A specific image capturing device for using on weaving machine based on CCD camera was designed. Image processing technique was used to measure the pickspacing in stop zone objectively. Five picks before and five picks after stoppage was considered as stop zone and the standard deviation of pickspacing was used as a criterion which interpret this defect. Dynamic loading of warp yarns were execute to evaluate the relaxation behavior of polyester multifilament warp yarns. 相似文献
184.
Etminan Samaneh Jalali Vahidreza Mahmoodabadi Majid Khashei Siuki Abbas Pourreza Bilondi Mohsen 《Paddy and Water Environment》2022,20(2):227-239
Paddy and Water Environment - Uncertainty in the model’s structure, parameters, and input data can be viewed as the three primary sources of hydrological models failure; hence, doing an... 相似文献
185.
Ms Salam A. R. Kabbara Ibrahim R. Abbas Joseph C. Scheerens Ann M. Tinsley James W. Berry 《Plant foods for human nutrition (Dordrecht, Netherlands)》1987,36(4):295-307
Tepary samples were examined for patterns of hydration, dry matter losses during the processes of soaking and cooking, residual hardness in partially cooked samples and heat lability of endogenous proteinaceous antinutritional factors. At 24 °C, teparies imbibed water equivalent to their weight (100% hydration) in 4 h and continued to absorb water rapidly for an additional 4 h before reaching an equilibrium hydration. During the processes of soaking and cooking, materials leached from raw beans represented 7.3 and 13.5% of their dry weight, 4.3 and 12.4% of their protein content, 7.1 and 12.2% of their stored carbohydrate and 22.4 and 33.4% of their mineral levels, respectively. In samples prepared at different cooking times (60, 90, 120, 150, 180 min) and cooking temperatures (80, 85, 90, 95°C), longer times and higher temperatures resulted in greater reductions in residual bean hardness; interactive effects of time and temperature treatments were significant. Residual activity of trypsin and chymotrypsin inhibitors in partially-cooked samples appeared to be negligible. In addition, at least 80% of the original hemaglutinating activity of lectins in raw beans was lost during partial-cooking of samples under all cooking regimes. 相似文献
186.
Mehdi Ghahartars Shabnam Abtahi Zahra Zeinali Mohammad Javad Fattahi Abbas Ghaderi 《Iranian Biomedical Journal》2021,25(2):88
Background:TNF-α and IL-6 are both pleiotropic cytokines playing major roles in cancer-associated cytokine networks. They have previously been investigated for their function in skin malignancies, mostly melanomas, and studies on NMSC patients are relatively rare. In this study, we aimed to assess the associations of serum levels of IL-6 and TNF-α with NMSCs and its clinicopathological features. Methods:This cases-control study was carried out to investigate the serum levels of TNF-α and IL-6 in 70 NMSC patients, in comparison with 30 healthy individuals, by means of flow cytometric bead-based immuneoassay. Results:Serum levels of both TNF-α and IL-6 were significantly higher in NMSC patients (6.470 vs. 4.355 pg/ml; p = 0.0468, respectively), compared to healthy individuals (3.205 vs. 0.000 pg/ml; p = 0.0126, respectively). In the subgroup analysis, SCC patients had higher serum levels of IL-6 compared to healthy individuals (3.445 vs. 0.000 pg/ml; p = 0.0432). No other significant differences were observed in the serum levels of these two cytokines among different clinicopathological subgroups of the patients. Conclusion:The increased levels of TNF-α and IL-6 in NMSC patients can be introduced as an epiphenomenon of a complex cancer-induced cytokine cascade. Key Words: Biomarkers, Cytokines, Interleukin-6, Tumor Necrosis Factor-alpha 相似文献
187.
Porifera have long been a reservoir for the discovery of bioactive compounds and drug discovery. Most research in the area has focused on sponges from tropical and temperate waters, but more recently the focus has shifted to the less accessible colder waters of the Antarctic and, to a lesser extent, the Arctic. The Antarctic region in particular has been a more popular location for natural products discovery and has provided promising candidates for drug development. This article reviews groups of bioactive compounds that have been isolated and reported from the southern reaches of the Arctic Circle, surveys the known sponge diversity present in the Arctic waters, and details a recent sponge collection by our group in the Aleutian Islands, Alaska. The collection has yielded previously undescribed sponge species along with primary activity against opportunistic infectious diseases, malaria, and HCV. The discovery of new sponge species and bioactive crude extracts gives optimism for the isolation of new bioactive compounds from a relatively unexplored source. 相似文献
188.
Prof. Dr. M. W. Roomi T. Abbas A. H. Shah S. Robina S. A. Qureshi S. S. Hussain K. A. Nasir 《Journal of pest science》1993,66(8):155-157
Four dominating species of fruit-fliesDacus zonatus, D. cucurbitae, D. dorsalis andD. ciliatus are widely distributed throughout Pakistan. They cause heavy damage to ripe and semi-ripe fruits and vegetables annually in our country. A natural attractant of plant origin, i.e., from Tulsi (Ocimum sanctum L.) was isolated and extracted in PCSIR Laboratories Complex, Karachi, with a view to applying for the control of fruit-flies. Different extracts of roots, stems, flowers, seeds, bark, and leaves were prepared in chloroform, acetone, ethylene chloride, ethanol, and ethyl acetate; and were tested for trapping fruit-flies in specially designed traps under different field conditions. A cotton pad (0.3 mg) treated with 0.25 ml of leaves extract in ethyl acetate is found to be a potent attractant for luring and trapping the fruit-flies (Dacus spp.) from a distance of 0.8 km. Methyl eugenol used as a standard attractant also gave the same results. 相似文献
189.
Ten Egyptian and imported entomopathogenic nematodes were evaluated for their pathogenicity to R. ferrugineus in both the laboratory and the field. In the laboratory, most nematodes were pathogenic to the pest larvae, pupae and adults. Larvae and adults were more susceptible to nematode infection (mostly 100?% mortality) than pupae enclosed in their cocoons. In the field however, the highest insect larval mortality was 66.67?% and most of nematodes failed in controlling the pest. Such failure could be due to hot weather, the tunnelling behaviour of the pest larvae and the too much sap in the infested sites in the trunks of palm trees. 相似文献
190.
Abbas Sharifi-Tehrani Marcello Zala Andreas Natsch Yvan Moënne-Loccoz Geneviève Défago 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(7):631-643
Fluorescent pseudomonads producing the antimicrobial compound 2,4-diacetylphloroglucinol (Phl) are being studied extensively for use as biocontrol agents of soil-borne fungal diseases. Some of them can produce pyoluteorin (Plt) in addition to Phl, whereas others synthesise only Phl. Here, a collection of seven Phl+ Plt- pseudomonads, seven Phl+ Plt+ pseudomonads and seven Phl- biocontrol pseudomonads were compared for protection of plant roots against fungal pathogens. The seven Phl+ Plt+ pseudomonads were identical by restriction analysis of amplified spacer ribosomal DNA (spacer ARDRA), whereas the Phl+ Plt- pseudomonads and especially the Phl- biocontrol pseudomonads were quite diverse by spacer ARDRA. Collectively, the Phl+ Plt- pseudomonads proved superior to the Phl+ Plt+ pseudomonads and the Phl- biocontrol pseudomonads for protection of tomato against Fusarium crown and root rot (in rockwool microcosms) or cucumber against Pythium damping-off (in non-sterile soil microcosms). There was no correlation between protection in vivo and inhibition of the corresponding fungal pathogen on plates. However, there was a significant correlation between the amount of Phl produced on plates and protection of tomato against Fusarium crown and root rot, but not with protection of cucumber against Pythium damping-off. Interestingly, the minority of strains unable to produce HCN, an extracellular protease, or both, were among those unable to protect plants in both pathosystems. A seedling assay was developed to compare pseudomonads for suppression of Fusarium crown and root rot in vitro, and a significant correlation was found between disease severity in vitro and in vivo. Overall, results suggest that promising biocontrol pseudomonads may be identified based on the ability to produce Phl and/or specific ARDRA-based fingerprints. 相似文献