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11.
It was evaluated whether trout hemoglobin (Hb)-mediated oxidation of minced washed cod muscle lipids could be prevented by an aqueous isolate from cod and some other muscle sources. Lipid hydroperoxides and painty odor developed approximately 4 days faster in washed than unwashed cod mince. When adding back an aqueous fraction (press juice) isolated from unwashed mince to washed mince at 2-6-fold dilutions, development of hydroperoxides and painty odor was either delayed or completely prevented. The inhibitory substances were heat stable, and their effect was slightly reduced at reduced pH. The <1 kDa fractions of whole and heated press juices were as inhibitory as the unfractionated press juices. Inhibition by the unheated, heated, and ultrafiltered (30 kDa) press juices was lost after dialysis. These findings implied the presence of one or more highly effective aqueous low molecular weight antioxidants in cod muscle press juice. The same antioxidative properties were found in heated haddock, dab, and winter flounder muscle press juices but not in heated herring and chicken muscle press juices. Unheated chicken press juice was however highly inhibitory. 相似文献
12.
The objective of this research was to study the effect of the antioxidants, delta-tocopherol, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tertiary butylhydroquinone (TBHQ), and propyl gallate in a model system of lean muscle and canola oil and to compare the effects with those in minced herring. Two carrier solvents with different dielectric constants (epsilon), ethanol (epsilon = 24) and oil (epsilon= 2), were used. Oxidation was measured using thiobarbituric acid reactive substances (TBARS) and sensory analysis. In both the lean muscle-canola oil model system and in herring muscle, the hydrophilic antioxidants, propyl gallate and TBHQ, were more effective in providing oxidative stability than the lipophilic antioxidants, delta-tocopherol and BHT. The oxidative stability of a cod muscle-canola oil system in the presence of propyl gallate, and delta-tocopherol was not affected by the dielectric constant of the carrier solvent, while BHA was more effective as an antioxidant when added in the polar solvent ethanol. 相似文献
13.
增加光照及其与改变源库互作对大豆产量构成因素的影响 总被引:8,自引:2,他引:6
生殖生长期间的光照强度是决定大豆产量的关键环境因素.在美国麻省和中国黑龙江两地,通过在不同时期,对不同密度的大豆群体进行增加光照和改变源库处理,研究了两地产量及产量构成因素对增加光照光变化的反应.结果表明,不同时期增加光照光处理的增产效果不同,开花初期和结荚初期增加光照最为明显,花期增加光照增加单株荚粒数,而结荚初期增加光照增加百粒重.鼓粒期增加光照处理,百粒重不同品种在不同密度条件下增产不显著,说明鼓粒期后的光照条件对大豆产量及百粒重的调节有限.在不同的光照条件下,源库在产量形成中的作用不同.在自然光照条件下,剪叶处理产量下降幅度较去荚大,即源在产量形成中更加重要些,而在花期的增加光照处理条件下,库也成为影响产量的重要因子,可见,光照条件在源库关系中起着显著的协调作用. 相似文献
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Herbert Offner 《Forstwissenschaftliches Centralblatt》1933,55(7):231-253
Ohne Zusammenfassung 相似文献
16.
Jian Jin Xiaobing Liu Guanghua Wang Liang Mi Zhongbao Shen Xueli Chen Stephen J. Herbert 《Field Crops Research》2010,115(1):116-123
Increasing yield is a high priority in most breeding programs. Approximately 600 soybean cultivars had been released by the end of the last century in Northeast China. Understanding the agronomic and physiological changes is essential for planning further plant breeding strategies in soybean. In this study, 45 representative soybean cultivars, from maturity groups 00 and 0, released from 1950 to 2006 in Northeast China were compared in field conditions for 3 consecutive years. A positive correlation between seed yield and year of cultivar release was indicated with a 0.58% average annual increase. Seed number per plant was the most important contributor to yield gain, with a 0.41% increase per year. Pod number per plant and seed size varied slightly with the year of cultivar release. Although variation in protein was from 37.0% to 45.5%, and oil concentration was from 16.7% to 22.0%, their concentrations were not consistently related to year of cultivar release. A 33% increase in the photosynthetic rate, 10.6% increase in plant dry weight and 19.0% increase in harvest index (HI) were found, while leaf area index (LAI) decreased by 17.3%. Modern cultivars have higher photosynthetic rates than their predecessors. The reduced plant height gave increased resistance to lodging, with the lodging score dropping from 3.2 in 1951 to 1.0 in 2006. Seed resistances to disease and pest infestation were also improved. Yield stability was enhanced over years, which could be attributed to the stable pod production across different environments. A flow diagram to explain the contributors to genetic improvement of soybeans in Northeast China was developed. 相似文献
17.
The annular ligament constriction is characterized by a disproportion between the available space and the contents within the fetlock tunnel. The main symptoms are a persisting lameness, distention of the tendon sheath, a typical "notch" when the fetlock is viewed from the side and a hyperflexion pain in the fetlock. The surgical treatment consists of the transection of the fetlock annular ligament. The conservative management can be considered as a independent therapy or as a preparation for a subsequent desmotomy. The medical records of 75 horses suffering from fetlock tunnel syndrome presented at the Veterinary Surgery Clinic of the University of Zurich were studied. 39 horses with 41 affected limbs were reexamined clinically and ultrasonographically. 70% of the surgical cases and 82% of the conservatively treated cases were judged to be sound. Altogether it can be said that the surgical case group had a success rate of 62% while the conservatively treated group showed a success rate of 58%. 相似文献
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Toxocara canis second stage larvae (L2) hatched in the stomach of mice and within 2 h reached all parts of the small intestine, the posterior half being the preferred site for larval penetration. Following penetration at the base of crypts of leiberkuhn they followed tortuous routes in the lamina propria, and entered the tunica muscularis obliquely. Larvae only appeared to be arrested in their migration in the submucosa and lamina propria by an inflammatory reaction composed mainly of lymphocytes and eosinophils. Larvae were seen entering and within lymphatic vessels as well as the peritoneal cavity and invasion of the vascular system followed though actual penetration of intestinal blood vessels was not seen. Proteolytic enzyme activity was detected in culture media in which L2 larvae were maintained. 相似文献