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81.
A specially designed scintillation probe has been assembled and applied in a promising diagnostic study of malignant melanoma in the human eye. When used in conjunction with a new radiopharmaceutical agent recently developed at The University of Michigan, 125I labeled chloroquine analog, the probe permits simple and nonsurgical gamma ray counting as a substitute for more elaborate techniques required in 32p beta scanning for the same prupose. Preferential uptake of the agent in ocular melanomas has been previously reported using a modified 5-inch NaI (Tl) crystal scanner as the detector. We have realized a substantial improvement in both sensitivity and reproducibility by substituting a hand-held probe placed in contact with the patient's closed eyelid. The counting rate over each eye is followed for a period ranging from 3 to 21 days after dosage. A melanoma in one eye gives rise to an enhanced rate over that eye. Data are presented on a total of 12 patients, including two with confirmed ocular melanomas. In both of these cases, the involved eye consistently shows a significantly greater activity than the opposite eye. In the remaining cases considered "negative", measured eye-to-eye asymmtries are much lower, and a measure of the variance associated with these cases is presented.  相似文献   
82.
83.
To establish cheese as a dairy product with health benefits, we embarked on examining the multifunctional role of cheeses, especially in the field of cancer prevention. The current study was designed to investigate whether different types of commercial goat cheeses may possess antiproliferative activity, using an HL-60 human promyelocytic leukemia cell line as a cancer cell model. Among 11 cheese extracts tested at 500μg/mL, 6 (Crottin de Chavignol, Pouligny Saint-Pierre, Chabichou du Poitou, Valencay, Kavli, and Sainte-Maure de Touraine) resulted in a significant decrease of cell viability, which is consistent with a decrease in viable cell number. Compared with the half-maximal inhibitory concentration (IC(50)) value of individual cheeses in cellular proliferation assays, the Pouligny Saint-Pierre extract showed strong inhibition. Incubation of cells in the presence of Pouligny Saint-Pierre extract resulted in induction of cellular morphological changes and apoptotic DNA fragmentation as well as expression of the active form of caspase-3 protein. Based on the quantification of the ratio of free fatty acids to triglycerides in different cheese samples, a significant correlation was detected between lipolytic ripeness and IC(50) values for antiproliferative capacity tested in HL-60 cells. Collectively, these results support a potential role of highly lipolyzed goat cheeses in the prevention of leukemic cell proliferation.  相似文献   
84.
This work aimed to evaluate the effect of certain factors on the production of volatile phenols from the metabolism of p-coumaric acid by lactic acid bacteria (LAB) (Lactobacillus plantarum, L. collinoides and Pediococcus pentosaceus). The studied factors were: pH, L-malic acid concentration, glucose and fructose concentrations and aerobic/anaerobic conditions. It was found that, in the pH range of 3.5 to 4.5, the higher the pH the greater the production of volatile phenols. This behaviour is correlated with the effect of pH on bacterial growth. Increasing levels of L-malic acid in the medium diminished the production of 4-vinylphenol (4VP) and stimulated the production of 4-ethylphenol (4EP) by L. plantarum NCFB 1752 and L. collinoides ESB 99. The conversion of 4VP into 4EP by the activity of the vinylphenol reductase may be advantageous to the cells in the presence of L-malic acid, presumably due to the generation of NAD+, a cofactor required by the malolactic enzyme. Relatively high levels of glucose (20 g/L) led to an almost exclusive production of 4VP by L. plantarum NCFB 1752, while at low concentrations (≤ 5 g/L), 4EP is mainly or solely produced. Part of the glucose may be diverted to the production of mannitol as an alternative pathway to regenerate NAD+. This is corroborated by the experiments done with fructose, a compound that can be used as an electron acceptor by some bacteria becoming reduced to mannitol. In anaerobiosis, the reduction of 4VP into 4EP is clearly favoured, which is consistent with the need to increase the availability of NAD+ in these conditions. This study shows that the amount and the ratio 4VP/4EP produced by LAB are greatly affected by certain environmental and medium composition factors. The behaviour of the bacteria seems to be driven by the intracellular NAD+/NADH balance.  相似文献   
85.
Discharge of Green House Gases (GHGs) and the management of municipal solid waste (MSW) continue to be a major challenge particularly in growing economies. However, these are resources which can be converted to green energy. Landfill gas which is essentially methane (50–55%) and carbon dioxide (40–45%) (both GHGs) is released from MSW by biodegradation processes. The estimation of this methane and its economic and environmental benefits for environmental sustainability are the objectives of this study. Methane emission from MSW disposed of in landfills was estimated using Intergovernmental Panel on Climate Change (IPCC) methodology. From the study, based on 8,196,000 tonnes MSW generated in Peninsular Malaysia in 2010, anthropogenic methane emission of about 310,220 tonnes per year was estimated. This was estimated to generate 1.9 billion kWh of electricity year?1 worth over RM 570 million (US$190 million). In addition, this leads to carbon dioxide reduction of 6,514,620 tonnes year?1 equivalent to carbon credit of over RM 257 million (US$85 million). These results were also projected for 2015 and 2020 and the outcomes are promising. Therefore, the exploration of this resource, besides the economic benefits helps in reducing the dependence on the depleting fossil fuel and hence broadening the fuel base of the country.  相似文献   
86.
The present paper proposes the impact of the air temperature on electricity demand as expected. It is clear that the annual maximum load is recorded versus the years starting by the year 2009 up to 2012. At present, the graph fitting technique is applied with some mathematical and computational tools based on the actual values of the years 2009 up to 2012 considering the lower values, the higher values and the average values of the annual maximum loads for Kingdom of Bahrain. For the three scenarios, the models are obtained by curve fitting technique. As well, the model of actual loads is obtained finally which has mostly the closest values obtained.  相似文献   
87.
Energy consumption has increased remarkably over the past half century mainly due to increasing population and economic development. The influences of these two factors are considered. In most developed countries, such as Japan, France, Germany and Korea, the growth rate of energy consumption is due to economic development. The effects of population in Germany and Japan will substantially decline. In the USA, it is due to both factors as well as in the developing countries, such as China, India, Indonesia and Latin America. Economic success is more effective than increasing population in China, India and Indonesia, while both factors are roughly equal in Latin America. In Africa, though the growth rate depends on the effect of increasing population, its contribution to world energy consumption is small. On a worldwide scale, the growth rate of energy consumption will be affected by improving standards of living.  相似文献   
88.
Hybrid composites La2‐xCoxCuO4 (x = 0, 0.1, 0.2, and 0.3) are prepared using one‐step simple hydrothermal route as electrodes for supercapacitors. The effect of varying cobalt content on morphological, structural, and electrochemical properties has been explored using X‐ray diffraction, scanning electron microscopy, and cyclic voltammetry, respectively. The structural parameters obtained by X‐ray diffraction showed tetragonal phase of hybrid composite without any evident impurity phases. The analysis of morphological properties suggested a strong correlation with electrochemical properties, for instance, a relationship between fabric porous structures and electrochemically active sites for redox reactions and intercalation/de‐intercalation processes. The hybrid composite electrodes demonstrated high specific capacitance of the order of 1304 F/g at 10 mV/s scan rate and exhibited decreasing trend on increasing scan rate. Hybrid composites were also tested for their ability as an electrode of high performance supercapacitors in different aqueous electrolytes, i. e, KOH, H2SO4, and Na2SO4 to optimize the best compatible electrolyte. The composite electrode material showed excellent cyclic stability and 98% capacitance retention for 1 A/g after 2000 cycles. The remarkable performance of hybrid composite electrode entails its potential for commercial applications of supercapacitors.  相似文献   
89.
In a field study an adjustable VDT workstation was given to each of the 68 operators for one week. The preferred settings, the body postures and subjective evaluations were assessed during normal working activities of the operators. The preferred ranges disclose the following figures: keyboard height (home row above floor) 71-87 cm, screen height (centre above floor) 92-116 cm, viewing angles (eye to screen centre) + 2 to -26 degrees, visual distance (eye to screen) 61-93 cm. There was practically no correlation between preferred settings and anthropometric data of body length or eye levels above floor. The study of body postures revealed that the great majority of operators tend to lean backwards with trunk inclinations between 97 degrees and 121 degrees (95% confidence interval). Some of the preferred settings strongly differ from those recommended in many brochures and standards. The physical complaints in the neck-shoulder and back area are diminished with the preferred settings.  相似文献   
90.
This paper focused on study of potential biopolymer carboxymethylcellulose (CMC) as electrolyte system for application in solid-state battery, which was prepared via solution casting technique. The highest conducting CMC biopolymer electrolytes (BE) was achieved at 1.12 × 10?4 Scm?1 with addition of 25 wt% NH4Br and was improved to 3.31 × 10?3 Scm?1 when plasticized with 8 wt% EC. The solid-state battery was assembled using both systems with the configuration Zn +ZnSO4.7H2O // highest conducting BE // MnO2 and showed promising performance at room temperature. This work implies that the possible practical application of the present biopolymer CMC as a new invention of electrolytes system in the fabrication of electrochemical devices.  相似文献   
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