首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   29篇
  免费   2篇
林业   4篇
基础科学   1篇
  9篇
综合类   5篇
水产渔业   3篇
畜牧兽医   7篇
植物保护   2篇
  2014年   1篇
  2011年   1篇
  2006年   2篇
  2005年   4篇
  2004年   3篇
  2002年   2篇
  2001年   1篇
  2000年   2篇
  1999年   2篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   2篇
  1990年   1篇
  1984年   2篇
  1983年   1篇
  1979年   3篇
  1964年   1篇
排序方式: 共有31条查询结果,搜索用时 15 毫秒
1.
Oat globulin was modified by a calcium-independent microbial transglutaminase (TG). The TG-polymerized protein had higher solubility than the control at acidic pH and had improved water- and fat-binding properties. Incubation of 10% (w/v) oat globulin dispersions in the presence of TG at 37 degrees C led to the formation of a well-developed viscoelastic gel network with a microstructure characterized by thick strands and large clusters. The TG-induced gels had higher modulus values, lower loss tangent values, and lower frequency dependency than the heat-induced gels. The TG-induced gel system has the characteristics of classical polymer gel with permanent "chemical" cross-links, whereas the heat-denatured system has the characteristics of a temporary "physical" gel with breakable cross-links. Fourier transform infrared spectroscopy showed marked shift and intensity changes in several major bands, suggesting pronounced changes in protein conformation during TG-induced gelation. Aggregation of protein molecules was also indicated by the progressive increases in two infrared bands (1679-1682 and 1622-1625 cm(-)(1)) associated with the formation of intermolecular beta-sheets and strands. Results suggest that new food polymers with unique functionality can be produced from oat globulin treated with TG and that elastic gels can be formed near neutral pH, instead of the alkaline pH required for thermally induced oat globulin gels.  相似文献   
2.
黄酮类化合物是具有广泛应用前景的天然药物。鱼腥草资源丰富,可作为黄酮类化合物的主要来源之一。阐述了鱼腥草黄酮类化合物的提取、分离方法,并对各提取分离方法的利弊进行了分析;提出了鱼腥草黄酮类化合物提取分离技术的发展前景。  相似文献   
3.
4.
乐果和三硫磷对为害苹果树的山楂紅蜘蛛和苹果紅蜘蛛均具较高的杀虫效力,后者尚有杀卵效能。这两种药剂对苹小食心虫显示良好的杀卵效力,乐果稍高于三硫磷。对初孵化幼虫同样具有一定的杀虫效力,也是乐果稍高于三硫磷。从田间防治試驗中初步看出,乐果和三硫磷对防治山楂红蜘蛛的效果良好,但逊于內吸磷。乐果防治苹小食心虫的效果接近于对硫磷,对卷叶虫較差;三硫磷防治卷叶虫的效果接近于对硫磷,对苹小食心虫较差。  相似文献   
5.
马铃薯、腌酸菜是青海农民及市民冬春季节最喜食的副食品,营养丰富,可口。但是马铃薯、腌酸菜,在贮存与腌渍过程中,会产生一些有害物质,如果食用不当就会发生中毒,甚至会致人中毒死亡。这主要是绿皮马铃薯中的龙葵素和腌咸菜中的亚硝酸盐所致。因此在加工、食用时应多加注意,少食或不食变质、腐烂蔬菜、腌渍不透的蔬菜和发芽、晒绿的马铃薯。  相似文献   
6.
Three food protein products, soy protein isolates, spray-dried egg white, and whey protein isolates, were chemically modified to varying levels with succinic anhydride, and the extent of modification of these proteins were determined by standard wet chemistry methods. Raman spectra (500-2000 cm(-1)) of the modified proteins were obtained. New C=O stretching vibrations were observed at 1420 and 1737 cm(-1) and were attributed to the carboxylate (COO-) and ester carbonyl (RCOO-) groups, respectively, which were appended to the proteins during succinylation. Two series of calibration curves were obtained by plotting the intensity ratio of the 1420 and 1737 cm(-1) to 1003 cm(-1) phenylalanine stretching band (used as an internal standard) against the extent of substituted epsilon-amino (and alpha-amino) groups and aliphatic hydroxyl groups, respectively. Linear fits were obtained with correlation coefficient r > 0.988. The Raman spectral data were also analyzed to study the effect of succinylation on the conformation of the three proteins. Some conformational changes were observed, including a transition from ordered to disordered structures, an exposure of tryptophan residues from a buried, hydrophobic microenvironment, and probably conformational shift of cystine residues.  相似文献   
7.
Secondary data sources can often be used to help address questions about the health status, health behavior, health resources allocation, and utilization of health services of rural Canadians. But the task of deciding which Canadian databases are amenable to rural health research remains a challenge. As part of a larger research project titled "Canada's Rural Communities: Understanding Rural Health and Its Determinants," an inventory of 51 Canadian databases that have the potential of being used for rural health research was compiled, and it continues to be maintained and updated. The websites maintained by two of Canada's leading statistical data centers were systematically searched, along with other published articles and national reports, to produce this inventory. The criteria used to determine which data sources to include in this inventory are: (1) databases containing data at the national level that can be accessed by researchers, (2) databases containing data that are relevant to a variety of rural health issues, and (3) databases containing data that could be partitioned into rural and non-rural geographies. Detailed information is available by searching the inventory of national rural health research-related databases through the internet (www.cranhr.ca) or by contacting the lead author of this article. This article examines some of the issues in developing this resource and demonstrates the usefulness of its contents to Canadian and other rural health researchers.  相似文献   
8.
In a longitudinal investigation (3 points of time n = 214, 206 resp. 202) the hemoglobin quota (Hb), the hematocrit (Hct) resp. the average corpuscular hemoglobin concentration (MCHC) were analysed at male calves receiving semi-liquid feed in the transitional period from pre-ruminal to ruminal digestion (56d). Breed, live weight development, consumption of milk, concentrated feed resp. dried forage, diseases of the calves as well as the father and the milk yield resp. the lactation age of the mother were registered as reference conditions. The percentage of calves with an Hb less than 10.5 g/dl was at the three points of time 50.00%, 86.41% resp. 41.58%, of calves with an Hct less than 33,5% it was 43.46%, 66.02% resp. 31.68% and of calves with an MCHC less than 30.5 g Hg/dl erythrocytes 51.87%, 76,21 resp. 47,03%. 21.50%, 33.50% resp. 4.46% of all test animals even had an Hb of less than 8.5 g/dl.  相似文献   
9.
195 rearing calves, which immediately after their gathering from various dairy farms had an anaemia frequency of 57.4% and an average age of 22 d and an average live weight of 43 kg, were at random divided into 3 groups and received in addition to the iron in the rations oral (B), intramuscular (C) or no (A) ferridextrane applications during their 56-day stay in the fluid feed range of a rearing farm. The average live weight gain of the calves during these 56 days in groups A, B, and C was 882 +/- 171, 949 +/- 145 and 912 +/- 170 g/d resp. and during the 57-day stay in the weaning range 664 +/- 205, 715 +/- 222 and 670 +/- 226 g/d resp. The significant advantage in the development reached by the calves in group B over those in group A during their stay in the fluid feed range did not get lost after the change to the weaning range. Based on the cost of medicine and on the development of the live weight of the calves in the 3 test groups in the fluid feed and weaning ranges the economic effect of ferridextrane applications was calculated. Under the rearing conditions given, iron intervention proved to be sensible for both health and economic reasons.  相似文献   
10.
The heat-induced aggregation of common buckwheat (Fagopyrum esculetum Moench) globulin (BWG) was studied using size-exclusion chromatography (SEC) combined with on-line multiangle laser light scattering (MALLS) and quasielastic light scattering (QELS). The unheated BWG was found to exist mainly as a hexamer, with an estimated weight-average molecular weight (M(w)) of 342 000, close to that deduced from the genomic cloned data of 13S buckwheat globulin. The QELS data predicted that the hexamer exists as two annular trimeric rings (diameter approximately 10.8 nm) placed on top of each other, forming an oblate cylinder (height approximately 9.1 nm). Upon heating, hexamers and trimers were dissociated and then associated to form extended small aggregates, finally forming compact, large macroaggregates. N-Ethylmaleimide would favor macroaggregate formation and increased the molar masses and hydrodynamic radii of the soluble aggregates, suggesting a different aggregation process in the presence of the sulfhydryl-blocking agent. A plot of log hydrodynamic radius versus log molar mass showed changes in the slope during heat treatment, suggesting conformational transformation in the heat-denatured and aggregated BWG molecules.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号