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排序方式: 共有49条查询结果,搜索用时 31 毫秒
1.
Viklund GA Olsson KM Sjöholm IM Skog KI 《Journal of agricultural and food chemistry》2008,56(15):6180-6184
Acrylamide is formed via the Maillard reaction between reducing sugars and asparagine in a number of carbohydrate-rich foods during heat treatment. High acrylamide levels have been found in potato products processed at high temperatures. To examine the impact of harvest year, information on weather conditions during growth, that is, temperature, precipitation, and light, was collected, together with analytical data on the concentrations of free amino acids and sugars in five potato clones and acrylamide contents in potato chips (commonly known as crisps in Europe). The study was conducted for 3 years (2004-2006). The contents of acrylamide precursors differed between the clones and the three harvest years; the levels of glucose were up to 4.2 times higher in 2006 than in 2004 and 2005, and the levels of fructose were 5.6 times higher, whereas the levels of asparagine varied to different extents. The high levels of sugars in 2006 were probably due to the extreme weather conditions during the growing season, and this was also reflected in acrylamide content that was approximately twice as high as in preceding years. The results indicate that acrylamide formation is dependent not only on the content and relative amounts of sugars and amino acids but also on other factors, for example, the food matrix, which may influence the availability of the reactants to participate in the Maillard reaction. 相似文献
2.
Per Wallgren Inger Marit Brunborg Gunilla Blomqvist Gunnar Bergstr?m Frida Wikstr?m Gordon Allan Caroline Fossum Christine Monceyron Jonassen 《Acta veterinaria Scandinavica》2009,51(1):13
Background
Postweaning Multisystemic Wasting Syndrome (PMWS) is an emerging disease in pigs of multifactorial origin, but associated to porcine circovirus type 2 (PCV2) infection. PMWS was first diagnosed in Sweden at a progeny test station that received pigs aged five weeks from 19 different nucleus herds on the day after weaning. The objective of this study was to examine, for the first time in an index outbreak of PMWS, the relationship between PCV2 virus, antibodies to PCV2 and serum amyloid a (SAA) in sequentially collected serum samples from pigs with and without signs of PMWS.Methods
Forty pigs of the last batch that entered the station at a mean age of 37.5 days were monitored for signs of PMWS during the first 55 days after arrival. Serum was collected on six occasions and analysed for presence of PCV2 DNA and antibodies to PCV2, as well as for levels of SAA.Results
Four of the pigs (10%) were concluded to have developed PMWS, with necropsy confirmation in three of them. These pigs displayed low levels of maternal antibodies to PCV2, more than 107 PCV2 viral DNA copies per ml serum and failed to mount a serological response to the virus. Starting between day 23 and 34 after arrival, an increase in PCV2 viral load was seen in all pigs, but PCV2 did not induce any SAA-response. Pigs that remained healthy seroconverted to PCV2 as the viral load was increased, regardless of initially having low or high levels of PCV2-antibodies.Conclusion
In this index case of PMWS in Sweden, pigs affected by PMWS were not able to mount a relevant serum antibody response which contributed to the disease progression. The maximal PCV2 virus load was significantly higher and was also detected at an earlier stage in PMWS-affected pigs than in healthy pigs. However, a viral load above 107 PCV2 DNA copies per ml serum was also recorded in 18 out of 34 pigs without any clinical signs of PMWS, suggesting that these pigs were able to initiate a protective immune response to PCV2. 相似文献3.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.4.
5.
The present study aimed at describing older persons’ experiences of outdoor environments at nursing homes in Sweden in terms of what factors are important and in what way they are important. Twelve residents and seven next of kin from three nursing homes participated in 16 interviews. Two main themes were identified. The first theme, access to nature and surrounding life, describes the outdoor environment as a means for change and as promoting a feeling of freedom. This theme calls for an inspiring design. The second theme, being comfortable in the outdoor environment, describes how important it is that going outdoors can be something easy and natural, and it calls for a comfortable design. The results are intended to facilitate practical knowledge that is useful to planners, decision-makers and care workers striving to create attractive and useable environments that are part of the daily life of nursing home residents. The themes also exemplify how the outdoor environment at nursing homes can serve as a resource in promoting restoration, a feeling of being at home and positive development late in life. 相似文献
6.
A rapid quantitative method for the gas chromatographic determination of volatile fatty acids in aqueous media is described. It includes the use of formic acid for the elimination of “ghost peaks” and of iso-valeric acid as an internal standard. The method has been used for the examination of bovine rumen fluid and of silage.Statistical treatment of the result shows that the fluid from lactating cows has a significantly higher content of butyric acid than has the fluid from dry cows; such a difference could not be demonstrated as to acetic, propionic and valeric acid.Some experience from the determination of the volatile fatty acids in silage is also reported. 相似文献
7.
Hoac T Lundh T Purup S Onning G Sejrsen K Akesson B 《Journal of agricultural and food chemistry》2007,55(10):4237-4243
To study the role of trace elements for the quality and nutritional value of bovine milk, the distribution of selenium, zinc, and copper in whey was investigated using a method linking size exclusion chromatography to inductively coupled plasma mass spectrometry (SEC-ICP-MS). Three major peaks were detected for selenium, two peaks for zinc, and five peaks for copper. More than 65% of the selenium was found in protein fractions, mainly in fractions coinciding with the major whey proteins beta-lactoglobulin and alpha-lactalbumin. All zinc was associated with low molecular weight compounds (<5 kDa) and one of these compounds was probably citrate. More than 60% of the copper eluted in protein fractions and two of the five major peaks probably contained metallothionein and citrate. This method was used to compare milk and whey produced by organic and conventional feeding procedures. The selenium content in whey and desalted milk produced using organic regimens was significantly lower than that in conventional samples. Moreover, the proportion of selenium in protein fractions of organic whey was significantly smaller than that in conventional whey, but the distributions of zinc and copper did not differ. This study showed that with the SEC-ICP-MS technique the distribution profiles of several trace elements in whey could be studied in the same run and that the selenium profile differed in whey produced by organic and conventional procedures. 相似文献
8.
Subgroups of canine antinuclear antibodies in relation to laboratory and clinical findings in immune-mediated disease 总被引:2,自引:0,他引:2
Hansson-Hamlin H Lilliehöök I Trowald-Wigh G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(4):397-404
Background: Autoimmune system diseases in dogs are commonly referred to as systemic lupus erythematosus (SLE), with a positive antinuclear antibody (ANA) test as a hallmark. In human patients, other systemic ANA-positive diseases with overlapping diagnostic features, referred to as SLE-related diseases, are described. Objectives: The objective of this study was to investigate whether different patterns of ANA reactivity represent different systemic autoimmune diseases in dogs. Methods: Dogs with serum positive for ANA by indirect immunofluorescence (IIF-ANA, titer ≥1:100) (n=56) were identified retrospectively from the patient population at the Department of Small Animal Clinical Sciences, Swedish University of Agricultural Sciences. Dogs were grouped on the basis of ANA staining patterns, and the results of immunodiffusion tests. Clinical, hematologic, serum biochemical, radiologic, and pathologic examinations were described for each group. Results: Dogs with a chromosomal–positive, homogeneous ANA staining pattern (n=14) had clinical signs involving multiple organ systems; 8 dogs were anemic. Dogs with a speckled IIF-ANA staining pattern (n=42) primarily had clinical signs of musculoskeletal disorders, fatigue and fever. Precipitating antibodies by immunodiffusion were found only in dogs with a speckled IIF-ANA staining pattern and comprised 4 different subgroups based on antigen specificity. Conclusions: In dogs with homogeneous IIF-ANA staining, SLE is a probable diagnosis because of the diversity of clinical manifestations and autoantibody reactivity against chromosomal antigens. Dogs with a speckled IIF-ANA pattern may have SLE-related diseases, which, in turn, may be correlated with different immunodiffusion subgroups. These syndromes had overlapping clinicopathologic features, as described for human patients. 相似文献
9.
The objective of this investigation was to comparemoisture conditions and Scots pine (Pinussylvestris L.) seed germination percentages in fourtypes of seedbed substrates, (i.e., feather mosses,mineral soil, humus, and ground organic material). Twoexperiments were conducted, with and withoutirrigation, in the summer of 1996 in a stand innorthern Sweden. The moisture conditions weredetermined by periodically weighing seedsamples. When plots were not irrigated, no seedsgerminated, probably because conditions were too dryin the seedbeds, as indicated by the low seed moisturecontent (under 15%). However, during rainy days, seedmoisture contents were relatively high (20–45%). Onthe irrigated plots the seeds germinated on allseedbed substrates, with the best germinationoccurring in humus (about 40%). Seed moisturecontents were high and relatively consistent in allirrigated seedbed substrates (35–55%). Inirrigated plots temperature rather than moisture, wasa limiting factor, and germination was highest in thewarmest seedbed types which are generally regarded aspoor germination substrates. We suggest that seedbedsin areas scheduled for harvesting be prepared in thestand before clear-cutting, and that the preparationshould enhance not only the substrates's water-holdingcapacity, but its thermal conductivity as well. 相似文献
10.
Monthly bulk deposition of chloride at 49 stations in Southern Sweden between 1989 and 1995 was used to produce quarterly and annual deposition maps through ordinary block kriging. Generally, deposition decreases from the west coast and eastward and displays a large annual variation, governed by the frequency and intensity of midlatitude cyclones. The 1st quarter dominates the temporal pattern all years except 1992. The 4th quarter is the second most important and the 2nd and 3rd quarters have generallylow deposition. The spatial deposition maximum was often displaced from the west coast to the western fringe of the South Swedish highland, due to orographic enhancement of precipitation. On the western rise of the highland, deposition almost entirely co-variates with precipitation. On the west coast and in the eastern part of Southern Sweden, thetemporal pattern is a more complex result of precipitation and frequency of strong westerlies. Comparing the quarterly total dataset with precipitation and frequency of westerly gales shows that both the 3rd and 4th quarters have higher mean precipitation than the 1st quarter, but lower deposition, while the second quarter has substantially lower precipitation but almost equal deposition to the 3rd quarter. The frequency of westerly gales shows a clearer, linear relationship to quarterly deposition. The 1st quarter has the highest variability in deposition and precipitation as well as in frequency of westerly gales. The importance of single highlysalt laden cyclones to the annual deposition is obvious in the 1st quarter of 1993. Changes in cyclone activity due to climate change is therefore of vital importance for the chemical characteristics of the midlatitude atmosphere. 相似文献