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   16篇
  免费   0篇
  7篇
农作物   1篇
畜牧兽医   7篇
园艺   1篇
  2019年   1篇
  2015年   1篇
  2014年   1篇
  2012年   4篇
  2011年   1篇
  2008年   1篇
  2006年   1篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
  2001年   1篇
排序方式: 共有16条查询结果,搜索用时 343 毫秒
11.
Foot and mouth disease (FMD) was detected in a wild boar in Southeastern Bulgaria in December 2010. The occurrence and spread of the disease in wild cloven-hoofed animals may pose an unexpected and significant threat to FMD virus (FMDV)-free areas within and outside the European Union. So far, only one well documented experimental infection with FMD in wild boar has been published. In order to obtain more epidemiologically relevant data regarding the disease in wild boar we conducted an experiment with the 2010 Bulgarian FMDV type O isolate. Two young wild boar were challenged while two domestic pigs and two additional wild boar served as contact controls. While the domestic pigs developed severe clinical signs of FMD, the wild boar showed relatively mild course of the disease. Viremia started in contact wild boar 2 days post exposure (DPE) and lasted until 6 DPE. The virus shedding lasted until 9 DPE. On 27 DPE, when the animals were slaughtered, viral RNA was detected in lymphoid tissues and oropharyngeal fluid but no virus could be isolated. Commercial ELISAs and virus neutralisation tests detected antibodies against FMDV on 8 or 6 DPE, respectively. The data of the present study will help to understand FMD in wild boar populations and can be used in models to evaluate the potential role of wild boar in FMD epidemiology.  相似文献   
12.
This study was conducted to measure the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se), and lead (Pb) in canine liver, renal cortex, and renal medulla, and the association of these concentrations with age, gender, and occurrence of chronic kidney disease (CKD). Tissues from 50 dogs were analyzed using inductively coupled plasma mass spectrometry. Cu, Zn, and Mn levels were highest in the liver followed by the renal cortex and renal medulla. The highest Sr, Cd, and Se concentrations were measured in the renal cortex while lower levels were found in the renal medulla and liver. Female dogs had higher tissue concentrations of Sr (liver and renal medulla), Cd (liver), Zn (liver and renal cortex), Cr (liver, renal cortex, and renal medulla), and Pb (liver) than male animals. Except for Mn and Sb, age-dependent variations were observed for all element concentrations in the canine tissues. Hepatic Cd and Cr concentrations were higher in dogs with CKD. In conclusion, the present results provide new knowledge about the storage of specific elements in canine liver and kidneys, and can be considered important reference data for diagnostic methods and further investigations.  相似文献   
13.
To meet the global demand for animal protein, sustainable intensification of existing livestock systems may be possible, especially through integration of livestock with crops or forestry. Thus, our objective was to compare forage production and animal performance in grass monoculture and integrated systems in the Brazilian Amazon biome. The four systems were (a) livestock (L) with Marandu palisadegrass {Brachiaria brizantha (Hochst. ex A. Rich.) R. D. Webster} as monoculture, (b) palisadegrass pastures integrated with eucalyptus trees (Eucalyptus urograndis; hybrid of Eucalyptus grandis W. Hill ex Maiden and Eucalyptus urophylla S. T. Blake) arranged in three‐row groves with groves spaced 30 m apart (livestock–forestry; LF), (c) palisadegrass after two years of crops (crop–livestock; CL) and (d) palisadegrass after two years of crops with single rows of eucalyptus trees spaced 37 m apart (crop–livestock–forestry; CLF). From July 2016 to July 2017, all experimental units were continuously stocked using a variable stocking rate. Greater herbage accumulation (HA) occurred in CL and CLF in comparison with L and LF (21,310, 24,050, 19,500 and 18,890 kg DM/ha respectively). The gain per hectare of L, LF and CL (average of 932 kg ha–1) was less than CLF (1,190 kg ha–1). Average daily gain was similar among systems (0.69 kg/day). We conclude that integrated systems can support similar (LF or CL) or greater (CLF) levels of animal production than palisadegrass monocultures while increasing diversity of outputs, thereby providing a greater range of viable systems for livestock production in the Brazilian Amazon biome.  相似文献   
14.
Citrus fruits contain a wide range of bioactive compounds. Their carotenoid fraction is inter alia dominated by structural cryptoxanthin isomers as beta-cryptoxanthin and zeinoxanthin. Both xanthophylls were identified in saponified citrus fruit extracts by comparison to reference compounds extracted from corn and by their typical fragmentation pattern in LC-(APCI)MS analyses. alpha-Cryptoxanthin, another structural cryptoxanthin isomer usually found in carrot leaves, was not identified in the citrus fruits studied. Cryptoxanthin concentrations of direct orange juices (D) and reconstituted juices (C) were compared. Although the respective mean values [beta-cryptoxanthin, 62 (C) versus 110 microg/100 g (D); zeinoxanthin, 22 (C) versus 37 microg/100 g (D)] were statistically distinguishable (P < 0.05%), a doubtless classification is not possible because the concentration ranges overlap. To identify esters of structural cryptoxanthin isomers in native orange juice extracts, four saturated acyl esters were synthesized. LC-(APCI)MS studies revealed for the first time that the dominant acylation partners of both xanthophylls were C12:0, C14:0, and C16:0 in nearly equal amounts of roughly one-third, whereas C10:0 and C18:1 were present at lower extents of 5-14%; other acylation partners were not identified. The presented method is appropriate to gain deeper insight into the pattern of structural cryptoxanthin isomers of citrus fruits. Knowledge of acylated cryptoxanthin isomers may be important in the evaluation of the bioavailability of individual esters in future human digestion studies.  相似文献   
15.
Carotenoids are found in food plants in free form or as fatty acid esters. Most studies have been carried out after saponification procedures, so the resulting data do not represent the native carotenoid composition of plant tissues. Therefore, nonsaponified extracts of 64 fruits and vegetables have been screened to determine the amount of carotenoid esters in food plants. Because one of the major problems in the quantitation of carotenoids is the availability of pure standard material, the total carotenoid ester content was calculated as lutein dimyristate equivalents. Lutein dimyristate was independently synthesized from lutein and myristoyl chloride. The highest ester concentrations were found in red chili (17.1 mg/100 g) and orange pepper (9.2 mg/100 g); most of the investigated fruits and vegetables showed concentrations up to 1.5 mg/100 g. Special attention was dedicated to beta-cryptoxanthin esters. To enable an accurate detection of the beta-cryptoxanthin ester content, beta-cryptoxanthin was purified from papaya and used for synthesis of beta-cryptoxanthin laurate, myristate, and palmitate, representing the major beta-cryptoxanthin esters in food plants. The study proved tropical and subtropical fruits to be an additional source of beta-cryptoxanthin esters in the human diet. The contents ranged from 8 microg/100 g beta-cryptoxanthin laurate in Tunisian orange to 892 microg/100 g beta-cryptoxanthin laurate in papaya.  相似文献   
16.
The xanthophylls lutein and zeaxanthin have attracted a lot of interest since it was presumed that an increased nutritional uptake may prevent adult macula degeneration (AMD). Although egg yolks serve as an important dietary source of lutein and zeaxanthin, data on xanthophyll concentrations in commercial egg yolks are not available. Thus, an high-performance liquid chromatography-diode array detector (HPLC-DAD) method was developed allowing for simultaneous separation of eight xanthophylls used to fortify poultry feed. Peak identification was carried out by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry [LC-(APCI)MS]. Egg yolks of four types of husbandry (seven batches each) were examined. Lutein and zeaxanthin were the predominant xanthophylls in egg yolks produced in accordance with ecological husbandry (class 0) because the concentrations of these xanthophylls ranged from 1274 to 2478 microg/100 g and from 775 to 1288 microg/100 g, respectively. Analysis of variance (ANOVA) proved that both mean lutein and mean zeaxanthin concentrations of eggs from class 0 were statistically discriminable from mean lutein and zeaxanthin concentrations from eggs of all other classes (P < 0.01). Mean concentrations of synthetic xanthophylls in eggs of classes 1 (free range), 2 (barn), and 3 (cage) were as follows: canthaxanthin, 707 +/- 284 microg/100 g; beta-apo-8'-carotenoic acid ethyl ester, 639 +/- 391 microg/100 g; and citranaxanthin, 560 +/- 231 microg/100 g. Experiments with boiled eggs proved that beta-apo-8'-carotenoic acid ethyl ester was the xanthophyll with the highest stability, whereas lutein was degraded to the largest extent (loss of 19%). Detailed knowledge about the xanthophyll amounts in eggs is indispensable to calculate the human uptake.  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