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961.
The 7S globulin from sesame seeds was purified by means of selective precipitation and anion-exchange chromatography on Q Sepharose Fast Flow. The 7S globulin migrated as a single band on native PAGE, which suggested homogeneity of the sample. The isolated protein was composed of at least eight polypeptide chains, ranging from 12.4 to 65.5 kDa, judged by SDS–PAGE analysis, and did not contain disulphide bonds. Furthermore, comparison of the polypeptide bands of the 7S and 11S globulins by SDS–PAGE indicated that the purified 7S globulin was free of legumin-like contaminant polypeptides and of 2S albumin. The identity of the purified polypeptides was verified by comparing the N-terminal amino acid sequences of the main polypeptide bands with the amino acid sequence deduced from a cDNA clone, which encoded the sesame 7S globulin precursor. Purification of the 7S globulin from sesame has not previously been reported. 相似文献
962.
A Ubeda M Díaz-Enriquez MA Martínez-Pascual A Parre?o 《Canadian Metallurgical Quarterly》1997,61(17):1651-1656
A number of experimental studies report that biological systems can be affected by in vivo exposure to low frequency and extremely low frequency electromagnetic fields. However, attempts to independently replicate some of these studies have shown the reported effects to be elusive. The difficulty in replicating results could be due to unidentified physical and/or biological parameters which may affect the response of a sample to electromagnetic fields. The present paper reports a failure to independently replicate a study showing that in vivo exposure to a pulsed magnetic field of 1.5 mT caused significant changes on plasma proteins in rats. Although the possibility has to be considered that the results from the seminal work were artifactual, substantial differences in levels of plasma proteins were observed between the control groups of the two studies indicating that the animals in the first study had an infectious illness. This observation supports the hypothesis that the state of physiological equilibrium of a biological system is crucial to its response to a potentially effective electromagnetic field. 相似文献
963.
Six groups of 1-day-old Warren chicks (seven per group) were fed for 15 days on diets with the protein supplement made of mixtures of soybean protein and dried yeast Saccharomyces carlsbergensis recovered from beer. The purpose was to establish the maximum substitution level of the soybean protein isolate by dried yeast, with the least possible related metabolic effects. Each group was fed one of the diets containing 0%, 25%, 50%, 75% and 100% of the protein supplement based on yeast protein, substituting the soybean protein isolate. In order to estimate the NPR value of the yeast protein, a group which received a protein-free diet, was also included. Protein utilization and changes in both plasma and liver total lipids, triglycerides, cholesterol and liver and kidney uric acid, were determined. In triglycerides, cholesterol and liver and kidney uric acid, were determined. In the groups fed diets with 75% and 100% of yeast protein, decreased body weight gain and PER and NPR values were observed, as well as an increment in the liver and kidney uric acid concentrations, although the diet consumption was not substantially modified. Thus, protein utilization, measured as PER and NPR, was lower in these groups. Plasma uric acid was not modified in neither group. The plasma lipids were not altered at whatever yeast concentration, while in the liver, total lipids as well as triglycerides decreased when the dietary yeast was increased. Results indicated that when using whole yeast cells recovered from beer in pre-starting rations for chicks, 50% of yeast protein is the maximum substitution level. 相似文献
964.
João Paulo Costa Pedro Cortesão Godinho João Carlos Clímaco 《International Transactions in Operational Research》2005,12(4):455-472
This paper presents a multiobjective financial planning model and a technique for characterizing its solutions through the visual exploration of the reference point space. The financial planning model includes two objectives: (1) to maximize the company's value and (2) to stabilize the company's capital structure. The model also considers other planning issues like the balance of funds, the stabilization of dividend payout over the years and some limitations on debt. A technique of visual exploration of the reference point space is proposed in order to characterize the non‐dominated (efficient) model solutions. The underlying idea is not simply to choose a plan or a strategy, but to learn, explore and classify different decision strategies, gaining insight into them according to the preferred model of the decision makers. 相似文献
965.
Angel M Zamarreo Jose M García‐Mina Rodrigo G Cantera 《Journal of the science of food and agriculture》2003,83(15):1607-1612
This paper describes a new and convenient methodology for studying the performance of products used in the treatment of ruminal acidosis. The method is based on potentiometric titration of the increase in buffer capacity and acid consuming capacity after the addition of products to a suitable medium at physiological rumen pH values. The testing medium is a mixture of buffer substances (phosphate, maleate and volatile fatty acids) that mimics real ruminal fluid in chemical composition, pH and temperature, providing useful experimental results allowing easy testing of antacids. This methodology was applied to the testing of four raw materials (sodium bicarbonate, two calcium carbonates and magnesium oxide). Results in good agreement with theoretical predictions and field experience were obtained. Copyright © 2003 Society of Chemical Industry 相似文献
966.
Chemical composition,nutritive value and voluntary intake of tropical tree foliage and cocoyam in pigs 总被引:1,自引:0,他引:1
Pascal Leterme Angela M Londoo Fernando Estrada Wolfgang B Souffrant Andr Buldgen 《Journal of the science of food and agriculture》2005,85(10):1725-1732
The composition of the leaves of cocoyam (Xanthosoma sagittifolium) and of two trees (Trichanthera gigantea and mulberry, Morus alba), their nutritive value in pigs and voluntary intake by pigs were determined. The average protein content ranged from 170 to 240 g kg?1 dry matter (DM) and that of neutral detergent fibres from 218 to 398 g kg?1 DM. The leaves are interesting sources of calcium (up to 69 g kg?1 DM), potassium, iron and manganese. The proteins are well balanced in essential amino acids, with lysine ranging from 43 to 57 g kg?1 proteins. The apparent faecal digestibility was determined by difference in 35 kg pigs fed a diet containing 35% leaf meal. The digestibility coefficients of DM, N and energy were, respectively, 47–57, 33–36 and 51–53%. The digestible energy value ranged from 1.674 to 2.037 kcal kg?1 DM. The voluntary intake of Trichanthera and Xanthosoma was measured in sows weighing 100 kg on average. The intake reached 3.4 kg fresh leaves day?1 (0.51 kg DM) and 1.0–1.1 kg dry leaf meal/day. It is concluded that low energy density is the main limiting factor of tree foliage for pig nutrition but that they are good sources of minerals and well‐balanced proteins. Copyright © 2005 Society of Chemical Industry 相似文献
967.
In the present study, the efficiency of several primer sets for the RT-PCR detection of hepatitis A virus (HAV) and astrovirus from both crude viral extracts and experimentally infected shellfish tissues was evaluated. Differences were observed depending on the primer set employed in the sensitivity of amplification of both viral types. For HAV primers, HAV240/HAV68 yielded the higher sensitivity: showing a detection limit of 0.02-0.1 infectious particles/microL or mg of tissue (either crude extracts or seeded mussel tissues). Regarding detection of AsV, a better performance was observed with primer set A1/A2 achieving a sensitivity of 0.1-1 PFU/microL or mg of tissue. The results obtained in this work strongly indicated that selection of primer sets to be employed for the routine detection of enteric viruses was a critical point in the design of the RT-PCR protocols. 相似文献
968.
Vales-Alonso J. de Vicente F.I. Gonzalez-Castano E.J. Pousada-Carballo J.M. 《Communications Letters, IEEE》2001,5(6):275-276
The authors propose a feasible real-time GSM terminal detector, to be located in a restricted area. All idle terminals entering it are forced to emit signaling information, which can be captured. As far as the authors know, market alternatives are nonexistent. A possible application is presented: a mobile terminal detector for airport access bridges 相似文献
969.
L. Rejn A. Rosas‐Zavala J. Porcayo‐Calderon V. M. Castao 《Polymer Engineering and Science》2000,40(9):2101-2104
Percolation in carbon black‐filled polymeric concrete, is discussed based on the measured changes in electrical conductivity and morphology of the composite at different concentrations of carbon black. The percolation threshold ranged between 6 and 7 wt% (based on resin weight) of carbon black. Above this concentration, the filler particles formed agglomerates in contact with each other, suggesting that the conduction process is nearly ohmic in nature. A power law predicted by percolation theory described the behavior of the conductivity as a function of carbon black content. Microscopic analysis showed the presence of a continuous structure formed by the polyester resin and carbon black, in which silica particles were embedded. 相似文献
970.
LS Belli L de Carlis G Rondinara AB Alberti G Bellati A De Gasperi D Forti G Idèo 《Canadian Metallurgical Quarterly》1998,27(6):1524-1529
Maintenance of adequate immunosuppression and avoidance of side-effects are the goals of long-term management of all organ-transplanted patients. We here report the final results of a prospective, randomized trial comparing early cyclosporine monotherapy versus double-drug therapy (cyclosporine and steroids) in adult liver transplantation patients. One hundred four patients were randomized 3 months after transplantation either to continue (Group I = 50 patients) or to stop steroids (Group II = 54 patients). Patients on a double-drug regimen were maintained long term on methylprednisolone at a dose of 0.1 mg/kg/d. Target cyclosporine trough levels were between 150 and 250 ng/mL in both groups. Our main points of interest were the prevalence of acute and chronic rejections and steroid-related side-effects in the two groups of patients. Mean follow-up was 41 +/- 16 months (range, 4-68 months). Patient actuarial survival 2 and 5 years after randomization was similar in the two groups (82% vs. 83% and 82% vs. 77%). The prevalence of acute rejections after randomization was, respectively, 8% and 4%. A single episode of chronic rejection was observed only in a patient on long-term steroid therapy. Side-effects of steroid therapy were less frequent in patients weaned off steroids, and when considering hypertension and diabetes, the differences between the two groups were statistically significant. Early cyclosporine monotherapy is a safe undertaking in liver transplantation because it allows a significant reduction of steroid-related side-effects without increasing the risk of acute and chronic rejection. After 5 years, patient survival was similar in patients with or without steroids. 相似文献