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991.
992.
Composition of the glutenin macropolymer: effects of flour quality and nonamylolytic enzyme addition 总被引:1,自引:0,他引:1
Cristina?Primo-Martín María?Antonia?Martínez-Anaya Concepción?CollarEmail author 《European Food Research and Technology》2004,218(5):428-436
The effects of the non-amylolytic enzymes pentosanase (PP), glucose oxidase (GLZ) and laccase (LAC), singly and in binary and ternary combinations, and wheat flour—a pure cultivar F0, and low- grade F1 and high-grade F2 commercial blends—on the electrophoretic pattern of the glutenin macropolymer (GMP) were investigated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE). GMP profiles of high (HMW), medium (MMW) and low (LMW) molecular weight glutenin subunits (GS) were correlated with dough and GMP characteristics and with bread quality and keepability.The total relative percentages of separated HMW, MMW and LMW-GS of GMP in control and enzyme-supplemented samples were: 33–37, 11–16 and 46–54% (F0), 47–74, 0 and 26–57% (F1) and 30–47, 15–18 and 32–38% (F2), respectively. HMW-GS/LMW-GS ratios, a quality index of glutenin, were found to range from 0.63 to 0.80 for all flour GMP. Enzyme addition induced moderate effects in pure wheat cultivar F0. Combinations of PP and GLZ (PPGLZ) allowed glutenin repolymerization after resting, leading to an increase of the bands of 104–107 and 88–90 kDa in GMP by SDS–PAGE. Analogously, PP plus LAC (PPLAC) and LAC alone increased the amount of the subunit of 81–82 kDa. Subunits of LMW increased with PPLAC and LAC, the subunit of 37–38 kDa having a higher percentage in GMP probably due to the presence of -, - and -gliadins besides the LMW-GS. Only the subunit of 81–82 kDa was positively associated with the dynamic rheological moduli G and G* and the subunit of 88–90 kDa correlated with a lower delta angle and, consequently, with a more elastic gel. After fermentation, the total percentage of subunits of HMW, MMW and LMW changed mainly in low-grade flour F1 (36–37, 17–19 and 14–19%) compared with high-grade flour F2 (32–37, 14–17 and 47–51%). The subunit of HMW with MW of 120–125 kDa (F1) and 93–95 kDa (F2) was positively correlated with the specific volume of breads and negatively with firmness of fresh and stored bread. Subunits of MMW negatively influenced the quality of fresh and stored bread of F1. The ratio HMW/LMW was positively correlated with bread firmness during staling in breads prepared with F2. 相似文献
993.
LD Kniazeva ES Ketuladze SA Lipkovich NN Zhilina VM Stakhanova 《Canadian Metallurgical Quarterly》1976,16(5):51-55
A method developed by the authors is described that consists in a quantitative test for the evaluation of the reactivity of the microvessels judging by the degree of changes in the resorption speed of isotopes from a tissue depot. In patients with essential hypertension an increased vascular reactivity was revealed with reference to angiotensin, noradrenalin and serotonin, as well as an increased duration of the effect of angiotensin. The highest vascular reactivity was noted in patients with stage II hypertension who have retained a hyperkinetic type of circulation. 相似文献
994.
Exact placement is an essential prerequisite for long-term use of a central venous catheter. Reported data show an extremely wide range of catheteral misplacements: from less than 1% to more than 60%. Some approaches appear to be less advantageous than others, but the highest rates of misplacement occur in the cubital, external jugular and saphenous veins. A series is presented of 378 radiographically controlled central venous catheters analysed for aberrant placement and loop formation. The total occurrence of faulty positioning and coiling reached 5.3%, while the respective incidences were 30% for the external jugular vein, 5.7% for the internal jugular vein, 5.5% for the infraclavicular technique of subclavian venepuncture, 5.3% for the innominate vein and 1.4% for the supraclavicular approach of subclavian venepuncture. The total frequency for pure loop formation was 2.9%. The authors discuss numerous reported data on catheter malpositioning, according to the specific techniques used, and compare them with thier own results. The relatively low incidence in the present series is possibly due to the high proportion of cases where the supraclavicular subclavian approach was used, the omission of the sphrenous/femoral and cubital techniques, and to pre-determining the length of the inserted catheteral segments. 相似文献
995.
Of 256 patients with a major spinal cord injury as a result of fracture of the cervical spine, 38 per cent had a laminectomy. Three months after injury, 33 per cent of the patients with laminectomy required fusion for instability compared to 22 per cent of the nonlaminectomy group. There were no cases of late instability in pure flexion or extension fracture groups. Ninety per cent of the late instability cases were in the groups with hyperflexion and flexion compression fractures. Laminectomy should be avoided for these fractures, but early fusion may be necessary to prevent progressive deformity. 相似文献
996.
Cytological investigations of the bronchial secretion and sputum in particular have acquired in recent years a great practical significance in pulmonary pathology. It is recommended to use cytodiagnosis along with prophylactic X-ray examinations of the population to detect pulmonary pathology, in particular among individuals with a higher risk of developing cancer. A substantiated opinion is put forward that cytodiagnosis should precede examinations of patients with clinico-roentgenologically confirmed changes in the lungs. 相似文献
997.
998.
Two cases of duodenal hematoma secondary to abdominal trauma in children are reported. The latent periods between trauma and the onset of symptoms were two and fifteen days. X-ray studies were conclusive for diagnosis. Pancreatic signs were mild in one case. Both cases were treated surgically, draining the fluid collection extramucosally. The authors advise surgical treatment whenever associated lesions need to be ruled out and when obstruction persists after the first days. 相似文献
999.
1000.