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1.
Plant Foods for Human Nutrition - The purpose of this study was to compare the yield, chemical composition, antimicrobial and antioxidant properties of essential oils isolated from leaves of Laurus...  相似文献   
2.
Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds.  相似文献   
3.
New Forests - The article [Effect of soil preparation method on root development of P. sylvestris and P. abies saplings in commercial forest stands], written by [Santa Celma, Katrīna Blate,...  相似文献   
4.
Although poppy seed oil is an expensive article of trade, no literature about identification methods for adulteration with cheaper vegetable oils, like sunflower oil, has been published. This kind of adulteration is a challenge for routine analytical methods, such as the determination of fatty acid composition, because of almost similar fatty acid ratios. The detection of adulteration of poppy seed oils with sunflower oils at different levels (5-40%, w/w) by using SPME-GC-MS and MALDI-ToF-MS is the subject of our investigation. With the mentioned SPME-GC-MS method, it was possible to detect an admixture of sunflower oils in all relevant (5-40%) amounts by using alpha-pinene as a marker compound. Admixture of sunflower oil with high levels of triolein (high-oleic acid type) could be undoubtedly detected by MALDI-MS down to the 5-10% level. In contrast, adulteration of pure poppy seed oil by "standard" sunflower oils remained indistinguishable using this MALDI-MS.  相似文献   
5.

Background

Previous studies indicated that the iron (Fe)/manganese (Mn) ratio in forage of sheep was significantly higher on scrapie-afflicted farms than on farms in other scrapie categories. This study was conducted to examine whether Fe and Mn in forage of sheep varied in general according to the scrapie status of different areas in the country. Copper (Cu) and zinc (Zn) were also included because of a possible relation to scrapie.

Methods

The country was subdivided into seven Areas (I-VII). Three Areas (I, IV, VII) were designated scrapie-free (never diagnosed or eradicated) and three as scrapie-endemic (II, III, VI); status of Area V was taken as unsettled. Of the harvest 2007 1552 samples were analysed from 344 farms all over the country, mostly grass silage from plastic bales (>90%) and from the first cut (70% or more). Results were expressed as mg kg-1 dry matter.

Results

Fe varied enormously from less than 100 mg kg-1 to 5000 mg kg-1. Mn varied nearly thirtyfold (17-470 mg kg-1). Fe concentration was significantly lower in Area I than in Areas II, V and VI. Mn concentration was significantly higher in Areas I, IV and VII than in Areas II, III, V and VI. The Fe/Mn ratio was significantly less in Area I than in the other areas (except Area IV). Mean Cu concentration was 6.6-8.3 mg kg-1 and the mean Zn concentration was 24-29 mg kg-1. They differed significantly in some areas.

Conclusions

1) Fe tended to be in lower amounts in sheep forage in scrapie-free than in endemic areas; 2) Mn was in higher amounts in forage in scrapie-free than endemic areas; 3) the Fe/Mn ratio was lower in scrapie-free than in endemic areas; 4) the Fe/Mn ratio may possibly be used as an indicator of scrapie status; 5) Cu and Zn in sheep forage were not related to scrapie; 6) further study on the role of Fe and Mn in the occurrence of scrapie in Iceland is needed.  相似文献   
6.
The biological control agent Rotstop® composed of a suspension of spores of Phlebiopsis gigantea (Fr.) Jül. is widely used for protecting conifer stumps from aerial infection by Heterobasidion species. The efficacy of Rotstop application on Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) stumps was determined in several locations and at different seasons in Latvia. Mean efficacy in controlling natural infection by Heterobasidion spp. in spruce stumps was 64%, calculated on the basis of number of infected stumps, and 89%, calculated on the basis of area of infected wood on sample discs cut from the stumps. Corresponding proportions for pine were 82% and 95%. The results show that Rotstop can be successfully used for stump treatment in Latvia, although improved efficacy is desirable, particularly in spruce. A Latvian isolate of P. gigantea, selected from numerous isolates in preliminary tests, was included in one experiment and was shown to be as effective as the Rotstop isolate. In untreated spruce stumps Heterobasidion spp. and P. gigantea were present in the same stump three times more frequently than in untreated pine stumps. Heterobasidion spp. infection in untreated spruce stumps was low when P. gigantea covered more than 10% of stump dissection.  相似文献   
7.
  1. Freshwater gastropods are imperilled globally and are among North America's most vulnerable major animal groups. Habitat loss, invasive species, and inadequate information about species distributions and assemblages all impair efforts to conserve freshwater gastropods. Conservation efforts are also impaired by difficulty obtaining and using distributional data for snails and other inconspicuous organisms, which are required to assess habitat associations.
  2. A gastropod‐specific sampling protocol was developed and used to survey 110 sites from 24 sub‐basins in two major river basins of the Intermountain West, USA. Habitat associations of individual taxa and groups of taxa that co‐occurred together more frequently than expected by chance were also examined.
  3. Using the gastropod‐specific sampling protocol, snails were found at most sites, even in regions where general macroinvertebrate sampling did not detect snails. Thus, these results show that general macroinvertebrate surveys do not accurately reflect the diversity of freshwater gastropods. Although snails of the same family are typically expected to live in the same habitats, this study found that in most cases, within a gastropod family, taxa exhibited unique habitat associations because they co‐occurred more frequently with taxa from different gastropod families. Five genera or sub‐genera were associated with specific mesohabitat or substrate types while two groups of co‐occurring taxa were associated with specific land classes or landform types.
  4. For diverse, inconspicuous taxa such as freshwater gastropods, qualitative, class‐specific sampling methods, and analyses of habitat associations based on co‐occurring taxa, rather than relatedness, should facilitate conservation efforts.
  相似文献   
8.

Background

Preliminary studies indicated decreased glutathione peroxidase (GPX) activity in blood of ewes on scrapie-afflicted farms. Other studies have shown decreased GPX activity in brain of prion-infected mice and in prion-infected cells in vitro. The aim of this study was to examine the GPX activity in blood as well as the distribution of GPX-activity levels from ewes on farms in scrapie-afflicted areas in Iceland.

Methods

Blood samples were collected from 635 ewes (non-pregnant [n = 297] and pregnant [n = 338]) on 40 farms in scrapie-afflicted areas during the years 2001–2005, for analysis of GPX activity. The farms were divided into three categories: 1. Scrapie-free farms (n = 14); 2. Scrapie-prone farms (earlier scrapie-afflicted, restocked farms) (n = 12); 3. Scrapie-afflicted farms (n = 14). For comparison, 121 blood samples were also collected from non-pregnant ewes on one farm (farm A) in a scrapie-free area (scrapie never registered). Chi-square test was used to test for normal distribution of GPX-results, and Kruskal-Wallis test to compare GPX-results between categories.

Results

The GPX-results appeared to be biphasically distributed in ewes in all three scrapie categories and on farm A. The presumptive breaking point was about 300 units g Hb-1. About 30–50% of the GPX-results from ewes in all three scrapie categories were below 300 units g Hb-1 but only about 13% of the GPX-results from ewes on farm A. The mean GPX activity was highest on farm A, and was significantly lower on scrapie-prone farms than on scrapie-free or scrapie-afflicted farms (non-pregnant and pregnant ewes: P < 0.005, respectively; non-pregnant and pregnant ewes combined: P < 0.0005).

Conclusions

1) the distribution of GPX-results in blood of Icelandic ewes apparently has a biphasic character; 2) the GPX-results were higher in ewes on one farm in a scrapie-free area than in ewes on farms in the scrapie-afflicted areas; 3) GPX-activity levels were significantly lowest on earlier scrapie-afflicted, restocked farms, which might have a bearing on the recurrence of sporadic scrapie on these farms; 4) further study on the possible role of GPX activity in the occurrence of scrapie in Iceland is warranted.  相似文献   
9.
New Forests - Soil preparation is a common practice that precedes outplanting of Norway spruce (Picea abies) and Scots Pine (Pinus sylvestris) in boreal forests. It has been proven to enhance the...  相似文献   
10.
Oral treatment with the water extracts of Scoparia dulcis whole aerial parts, at doses of 50, 100 and 200 mg/kg, dose dependently inhibited the indomethacin-induced gastric damages in rats.  相似文献   
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