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941.
鸡实验性尿酸盐沉积症的肾脏病理学研究 总被引:5,自引:2,他引:3
将120只35日龄迪卡商品代蛋用雏鸡随机分为高钙组、高蛋白组和对照组,分别饲喂高钙(含钙3.9%)、高蛋白(含粗蛋白44.0%)和全价(含钙0.8%,粗蛋白18.2%)饲料。试验第25天,各组剖检5只鸡,作肾脏的光镜和电镜观察。结果表明,高钙、高蛋白饲料均能引发尿酸盐沉积。高钙组鸡肾脏肿大,表面及切面有大量尿酸盐结晶;输尿管扩张,管内充满白色尿酸盐沉积物。光镜观察,肾小球肿胀,近曲及远曲小管上皮细胞肿胀、变性。电镜观察,近曲小管上皮绒毛短缩、肿胀、断裂、脱落,线粒体肿胀、嵴断裂;远曲小管线粒体肿胀,呈现空泡,核呈锯齿型。高蛋白组眼观病变不明显,肾脏的光镜、电镜病变与高钙组相似,但损伤程度较轻。作者认为,高钙、高蛋白所致肾脏损害是鸡尿酸盐沉积症的重要原因。 相似文献
942.
新疆野生油菜芥酸含量的遗传分析 总被引:5,自引:2,他引:3
通过新疆野生油菜高、低芥校组合正反交F1、F2,回交一代及相应的杂交亲本种子中芥权的测定,分析了新疆野生油菜芥酸的遗传。结果表明,新疆野生油菜芥权酸含量受两对加性基因控制,每个芥权基因控制的芥量为5%左右。 相似文献
943.
《Journal of Crop Improvement》2013,27(1-2):345-369
Abstract Oil quality in vegetable oils is determined by both nutritional and functional aspects, which are, in turn, primarily determined by the fatty acid profile (i.e., fatty acid composition) of the oil. The naturally occurring fatty acid composition of Brassica oils has been extensively modified using conventional plant breeding and biotechnology-based techniques to create unique and improved quality vegetable oils. New Brassica cultivars displaying a wide range of edible oil qualities have been developed, and commercialized in recent years. Improved Brassica cultivars which produce an industrial oil have also been developed and commercialized in the last two decades. World vegetable oil markets are highly competitive, so the steady improvement in oil quality of the Brassica oilseeds is essential to maintain or increase market share, and/or to create new niche markets. The main challenges facing Brassica oilseed breeders are (1) to determine the desirable fatty acid profiles of the oil for each end-use market application to create improved oils and (2) to quickly develop improved Brassica cultivars which can produce the new fatty acid profile oils at competitive prices. 相似文献
944.
945.
《Journal of plant nutrition》2012,35(3):418-428
AbstractAlthough crude oil contamination is a constraint for crop production, some plants can develop under crude oil contaminated conditions by utilizing crude oil as nutrients after decomposition. A greenhouse trial was conducted to investigate growth, nutritional composition and enzymatic response of vetiver grass in confronting with crude-oil contamination as affected by gibberellic acid (GA) and Tween 80. Application of GA or co-application of GA with Tween 80 significantly increased mean shoot dry weight. Application of Twee 80 alone or in combination with GA significantly increased mean root dry weight as compared to control which was attributed to the effectiveness of Tween 80 alone or in combination with GA on the removal of total petroleum hydrocarbons from polluted soil. Application of crude oil diminished shoot phosphorus, iron, zinc and manganese uptakes. Application of GA and Tween 80, however, compensated the decrease in nutrient uptakes in vetiver grass resulted from crude-oil contamination. Application of crude oil at both 2 and 4% (W/W) levels increased catalase (CAT) activity and proline (PRO) content. Superoxide dismutase (SOD) activity increased only following the application of 2% crude oil level, while addition of all amendments decreased CAT activity. Addition of GA decreased activity of SOD. None of the studied amendments had a significant effect on PRO content. Application of a combination of GA and Tween 80 under crude oil contamination are recommendable since such treatments not only inhibited adverse effect of crude oil on nutrients uptake but also caused that vetiver grass tolerated high level of crude oil contamination. 相似文献
946.
947.
Improved planting methods and foliar application of glycinebetaine (GB) and salicylic acid (SA) can improve the water productivity in field crops under limited water supply conditions. A 2‐year field study was conducted to evaluate the possible role of different planting methods and foliar applications of GB and SA in improving the yield, quality and water productivity of hybrid sunflower (Helianthus annuus L.). The crop was planted by flat sowing (75 cm spaced rows) and ridge sowing (75 cm spaced ridges), with GB and SA applied exogenously at 100 and 0.724 mm , respectively, at both budding and flowering stages, while control plots received distilled water. Ridge sowing, rather than flat sowing, improved the biological yield, oil yield, leaf area index (LAI), crop growth rate (CGR), plant height, water‐use efficiency and final achene yield during both the years. Foliar applications of GB and SA at both the stages improved the achene yield, although foliar application of GB at flowering was the most effective. Neither the planting methods nor the foliar application of GB and SA altered the achene oil contents during both the years. Foliar application of GB and SA increased the free proline content of the leaf and GB contents at flowering but reduced the achene protein contents, whereas planting method had no effect on these attributes across the years. Of the foliar applied chemicals, GB was more effective in improving sunflower growth and yield and water productivity than SA. To conclude, ridge sowing coupled with foliar application of GB at flowering stage could be beneficial for achieving maximum yields of hybrid sunflower under relatively water limited conditions in the field. 相似文献
948.
合成了3个新的锰-超氧化物歧化酶(Mn-SOD)模拟物Mn(L-Leu)2(1),Mn(L-Val)2·3/2HCl(2)和Mn(L-Phe)2·HCl(3)(L-Leu=L-亮氨酸,L-Val-L-缬氨酸和L-Phe=L-苯丙氨酸).用元素分析、红外光谱对模拟物进行了表征.并用 NBT 光还原法检测了模拟物的SOD活性.结果表明3个模拟物均具有相对较高的类似于 SOD 催化超氧阴离子自由基(O2·-)歧化活性,抑制率为 50%时配合物的浓度,即一个活性单位值 IC50值分别为 0.311、0.274 和 0.378μmol/L.有望成为具有良好应用前景的新型 SOD 模拟物抗拟增产剂而应用于农业生产中. 相似文献
949.
The effect of variations in the amount or quality of food provided on the amino acid profile of larvae, was tested in two marine fish species, the Senegal sole (Solea senegalensis) and the sea bass (Dicentrarchus labrax). The objective was to assess whether such nutritionally suboptimum dietary patterns, which simulate situations that may occur in hatcheries, result in variations in the concentration of one or more amino acids that could be used as indicators of nutritional condition of larvae. Restriction in the normal food ration by 60% had no clear effect on the amino acid profile of sea bass, while the concentration of some amino acids (Arg, Ala and Phe) showed significant variations in sole. Feeding on artificial diets, which have shown their inadequacy a priori, resulted also in no significant effect on the profile of sea bass, but in a dramatic modification of the amino acid profile in sole. In addition, changes in the amino acid profiles considered as a whole were evaluated using the cluster analysis instead of paired comparisons between amino acid concentrations in each treatment. The analysis clearly separated profiles of larvae fed restrictedly or inadequately from their controls, irrespective of the species. This demonstrated the potential value of evaluating whole changes in amino acid profile as nutritional indicator. Besides, it was demonstrated that sensitivity of larvae to nutritional changes that may be reflected in the amino acid profile is greatly conditioned by the species and developmental stage. 相似文献
950.
Masanori TOHNO Hisami KOBAYASHI Masaru NOMURA Maki KITAHARA Moriya OHKUMA Ryuichi UEGAKI Yimin CAI 《Animal Science Journal》2012,83(2):111-120
Twenty-three lactic acid bacteria (LAB) isolated from three cultivars (Akiaoba, Nagahahikari and Tachiwase) of Italian ryegrass (Lolium multiflorum Lam.) silage were precisely characterized by a combination of phenotypic tests, genotypic 16S ribosomal DNA sequencing and rapid PCR-based analyses, focusing on their useful phenotypes for silage preparation as inoculants. We successfully identified both at the species and subspecies levels: phenotypically novel Lactococcus lactis subsp. lactis, Lactobacillus brevis, Lactobacillus coryniformis subsp. torquens, Lactobacillus curvatus, Lactobacillus plantarum subsp. plantarum, Lactobacillus sakei subsp. carnosus, Leuconostoc mesenteroides subsp. dextranicum and Pediococcus parvulus. This is the first report to elucidate the presence of Lactobacillus coryniformis ssp. torquens and Leuconostoc mesenteroides subsp. dextranicum in Italian ryegrass silages. Physiological and biochemical tests revealed that phenotypic characteristics are different among the different strains of the same species and subspecies, and that the isolates show unique and diverse phenotypes related to fermentation factors, such as available carbohydrates, optimal growth pH and temperature. These results suggest that, for various well-preserved silage preparations, the isolates may be useful in producing novel inoculants corresponding to their optimally climatic and ecological niches. 相似文献