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31.
Jerome C. Pekas 《Pesticide biochemistry and physiology》1983,19(1):31-35
A method for the total collection of portal vein blood over extended periods has been developed. The method has been applied in gastrointestinal toxicology research involving rats. The method facilitated quantitative recovery of portal vein blood for 120 min for measurement and identification of absorbed radiolabeled components derived from a toxic lipphilic pesticide placed in the lumen of the small intestine. The method can be applied to any substance—nutrient, anutrient, xenobiotic chemical, or endocrine factor—absorbed into the portal vein from the gastrointestinal tract. The method (a) provides for collection of compounds absorbed from the gastrointestinal tract before distribution to nondigestive tissues (i.e., liver), (b) allows measurement of the compounds absorbed without the need to monitor flow rate, and (c) facilitates accumulation of sufficient material from the total portal circulation for analyses when submicrogram quantities are absorbed. The latter two features are important but impossible to attain with small samples of portal blood and are crucial in research with minute quantities of substrate. These features become requirements in metabolism and toxicology research. The method involves replacement of the portal blood with a suspension of perfluorohydrocarbons to substitute for the major functions of natural blood. The total-continuous portal vein fistula makes it possible to investigate metabolic and transport phenomena in live animals which previously could be explored only by in vitro methods. The method may be applied to conscious animals with further refinements. 相似文献
32.
Several studies ofLeveillula taurica have been carried out in India, France, Israel and the USA. This report describes a promising source ofL. taurica resistance that can be incorporated into Mediterranean pepper cultivars. The present data suggest that full resistance depends
on three pairs of genes. 相似文献
33.
Jerome T McKay Tiffany A Brigner Brian E Caplin Kimberly S McCurdy Richard L Forde 《Journal of veterinary diagnostic investigation》2008,20(2):209-212
The objective of this study was to report a reliable real-time polymerase chain reaction assay compatible with the Roche LightCycler 2.0 capable of genotyping sheep for scrapie susceptibility at codon 171. The single nucleotide polymorphisms (SNPs) in the prion protein gene in sheep that may govern resistance to scrapie at codon 171 encode for lysine (K), histidine (H), glutamine (Q), and arginine (R). A modified proteinase K method for leukocytes or whole blood was used to isolate genomic DNA from sheep blood. Fluoresentric developed and optimized primers and probes for the codon 171 SNP assay. The assay was initially validated using 218 determinations from whole blood of known genotypes with 100% correct identity. The assay was further validated through a whole-blood check test provided annually by the National Veterinary Services Laboratory with a correct identification rate of 100%. From January 2005 to December 2006, 3,672 samples from blood were genotyped at codon 171. The genotypes were QR(171) (n = 1,838, 50.05%), RR(171) (n = 1,423, 38.75%), QQ(171) (n = 407, 11.08%), HR(171) (n = 2, 0.05%), and HQ(171) (n = 2, 0.05%). The combination of this simple extraction method and the novel Fluoresentric assay is very accurate, is capable of identifying all 4 SNPs at codon 171 in one reaction, and has proven to be a useful tool for producers in their selective breeding programs. 相似文献
34.
Jerome K. Vanclay 《Small-Scale Forestry》2007,6(2):177-188
An on-line survey during August–September 2006 examined community attitudes toward private native forestry. Views expressed
by the 156 respondents confirmed prior hypotheses that attitudes would correlate with associations (e.g. professionals in
favour of incentives, farmers in favour of freedom to manage, conservationists in favour of regulations), and with interest
(biodiversity enthusiasts in favour of regulations, producers in favour of incentives), but refuted the prior hypotheses that
urban dwellers would be more likely to favour regulations. Respondents appear to reflect different constituencies with divergent
views without a shared understanding of the condition and dynamics of private native forests in NSW. This indicates the need
for more extension and public education, particularly since forests continue to be an election issue. The survey did not gauge
support for private native forestry, but helps to untangle the views from the constituencies promoting them. Regulatory approaches
received most support from respondents affiliated with an environmental group, with a national concern for biodiversity, who
fear that private native forests are in poor condition and will degrade further. Advocates for more landholder freedom tend
to be landholders who believe that private native forests are in better condition than comparable State Forests, and who are
optimistic about the future for private native forests. Advocates for incentives tend to be urban dwellers with a production
focus and professional affiliation. 相似文献
35.
Wavell Standa-Gunda Tendayi Mutimukuru Richard Nyirenda Ravi Prabhu Mandy Haggith Jerome K Vanclay 《Small-Scale Forestry》2003,2(2):313-326
Participatory modelling can be a useful process to encourage critical examination of livelihood options and foster sustainable
natural resource use through enhanced social learning, collective action and mobilization. The broom-grass group in the Mafungautsi
Forest Reserve serves as a case study of the process and outcomes of such participatory modelling. Innovative group facilitation
methods enhanced participation in the modelling process. The modelling process complements broader efforts to achieve higher
levels of adaptive collaborative management.
This work was conducted as part of the Adaptive Co-Management project of CIFOR, the Center for International Forestry Research.
We are grateful to the UK’s Department for International Development (DFID) and the European Community for financial support
of this project. 相似文献
36.
Ravi Prabhu Mandy Haggith Happyson Mudavanhu Robert Muetzelfeldt Wavell Standa-Gunda Jerome K. Vanclay 《Small-Scale Forestry》2003,2(2):185-210
ZimFlores (version 4) is the outcome of a participatory modelling process and seeks to provide a shared factual basis for
exploring land-use options for the communal lands surrounding the Mafungautsi forest. The ZimFlores experience underscores
the importance of a sharing a common problem and a common location in which all participants have an interest. Participatory
modelling has proved an effective way to consolidate a diverse body of knowledge and make it accessible. Results demonstrate
the importance of model outputs that are diagnostic, and which offer insights into the issues under consideration.
Many people contributed in many ways to help realize ZimFlores. Some of the people who contributed include Elias Ayuk, Ivan
Bond, Ephraim Chabayanzara, Muyeye Chambwera, Vijay Datadin, Wil de Jong, Peter Frost, James Gambiza, Jode Garbe, Peter Gondo,
Emmanuel Guveya, Chiedza Gwata, John Hansell, Gideon Kamumvuri, Godwin Kowero, Dominic Kwesha, Chris Legg, Tim Lynam, Hilton
Madevu, Simba Mandota, Everisto Mapedza, Frank Matose, Gutura Matoso, Chipo Mlambo, John Mudekwe, Maxwell Mukwekwerere, Dorcas
Mungwari, Tendayi Mutimukuru, Mkhululi Ngwenya, Richard Nyirenda, Bill Ritchie, Lizwelabo Sibanda, Manasa Sibanda, Fergus
Sinclair, Jivas Sithutha, Jasper Taylor, Michael Thomas, Zivanai Tsvuura and Steve Twomlow. We are grateful to the UK’s Department
for International Development (DFID) and the European Community for financial support of this project. 相似文献
37.
The underlying mechanisms governing nonenzymatic pectin and pectate degradation during thermal treatment have not yet been fully elucidated. This study determined the extent of nonenzymatic degradation due to beta-elimination, acid hydrolysis, and demethylation during prolonged heating of citrus pectins and its influence on physicochemical properties. Solutions of citrus pectins, buffered from pH 4.0 to 8.5, were heated at 75, 85, 95, and 110 degrees C for 0-300 min. Evolution of methanol and formation of reducing groups and unsaturated uronides were monitored during heating. Molecular weight and viscosity changes were determined through size exclusion chromatography and capillary viscometry, respectively. Results showed that at pH 4.5, the activation energies of acid hydrolysis, beta-elimination, and demethylation are 95, 136, and 98 kJ/mol, respectively. This means that at this pH, acid hydrolysis occurs more rapidly than beta-elimination. Furthermore, the rate of acid hydrolysis is diminished by higher levels of methyl esterification. Also, citrus pectin (93% esterified) degrades primarily via beta-elimination even under acidic conditions. Acid hydrolysis and beta-elimination caused significant reduction in relative viscosity and molecular weight. 相似文献
38.
Iliev ID Funari VA Taylor KD Nguyen Q Reyes CN Strom SP Brown J Becker CA Fleshner PR Dubinsky M Rotter JI Wang HL McGovern DP Brown GD Underhill DM 《Science (New York, N.Y.)》2012,336(6086):1314-1317
The intestinal microflora, typically equated with bacteria, influences diseases such as obesity and inflammatory bowel disease. Here, we show that the mammalian gut contains a rich fungal community that interacts with the immune system through the innate immune receptor Dectin-1. Mice lacking Dectin-1 exhibited increased susceptibility to chemically induced colitis, which was the result of altered responses to indigenous fungi. In humans, we identified a polymorphism in the gene for Dectin-1 (CLEC7A) that is strongly linked to a severe form of ulcerative colitis. Together, our findings reveal a eukaryotic fungal community in the gut (the "mycobiome") that coexists with bacteria and substantially expands the repertoire of organisms interacting with the intestinal immune system to influence health and disease. 相似文献
39.
Hogsette JA 《Pest management science》2003,59(6-7):835-841
An overview of ARS research in the field of veterinary pests is presented. Results of research from the past three years on ticks, fire ants, nuisance flies, mosquitoes, sand flies and black flies, among others, are included. Where applicable, significance of research is discussed. 相似文献
40.
Wood C Almes K Bagladi-Swanson M Debey B Andrews G Nietfeld J Wilkerson M 《Journal of the American Animal Hospital Association》2008,44(3):144-148
Sézary syndrome is an uncommon leukemic variant of cutaneous lymphoma in cats. This cat had recurrent dermatitis with erythematous, pruritic plaques. Multiple skin imprints and biopsy samples were obtained over a 6-month period, and histopathological findings were consistent initially with eosinophilic miliary dermatitis and later with erythema multiforme. One week before death, Sézary cells were identified in the peripheral blood that expressed cluster of differentiation (CD)3 and CD8 antigens. Massive infiltration of CD3+ lymphocytes was noted in the skin and multiple internal tissues by histopathological examination. This case demonstrates the difficulty in diagnosing cutaneous lymphoma early in the disease course. 相似文献