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1.
Stands of clonal Salix viminalis (in 1985) and Populus trichocarpa(in 1986) were grown for one growing season from cuttings incontainers, at 0.3 m spacing, supplied with trickle irrigationand nutrients. Woody biomass production (Bw) in the first yearwas analysed as the product of the proportion of dry matterpartitioned to wood ({macron}), the seasonal mean efficiencywith which intercepted light was used to produce dry matter({macron}), the mean fraction of incident light interceptedby the canopies (f{macron}), and the amount of incoming solarradiation over the season (A). Thus, Bw = {macron}f{macron}{macron}A. For Salix, Bw=10 t ha1y1, while for Populus, Bw= 5 t ha1y1, mainly because of differences in{macron} and f{macron}. The Populus partitioned more dry matterto roots (and correspondingly less to stems) and interceptedless light over the growing season. The Salix and Populus cloneshad surprisingly similar ({macron}) values, namely 1. 58 and1. 50 g MJ1, respectively (based on total dry matterand total solar radiation), which are very like the {macron}values measured on C3 agricultural crops in Britain. Also, theSalix and Populus clones produced canopies with similar lightextinction coefficients and hence similar relationships betweenfractional interception and leaf area index. 相似文献
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The physical conditions of the Border hills are briefly described.The general problems of both private and State-owned woodlandsare discussed; in particular those of afforestation of peatareas and the danger of windblow. Future management and regenerationis considered and the probable methods to be used are suggested. 相似文献
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Acke E Carroll C O'Leary A McGill K Kelly L Lawlor A Madden RH Moran L Scates P McNamara E Moore JE Jones BR Fanning S Whyte P 《Irish veterinary journal》2011,64(1):6-4
The genetic similarity of Campylobacter jejuni isolates from pets, compared to human clinical cases and retail food isolates collected in Ireland over 2001-2006 was investigated by cluster analysis of pulsed-field gel electrophoresis (PFGE) fingerprinting profiles. Comparison of the PFGE profiles of 60 pet isolates and 109 human isolates revealed that seven (4.1%) profiles were grouped in clusters including at least one human and one pet C. jejuni isolate. In total six (1.6%) of 60 pet and 310 food profiles were in clusters with at least one food and one pet C. jejuni isolate. The detection of only a small number of genetically indistinguishable isolates by PFGE profile cluster analysis from pets and from humans with enteritis in this study suggests that pets are unlikely to be an important reservoir for human campylobacteriosis in Ireland. However, genetically indistinguishable isolates were detected and C. jejuni from pets may circulate and may contribute to clinical infections in humans. In addition, contaminated food fed to pets may be a potential source of Campylobacter infection in pets, which may subsequently pose a risk to humans. 相似文献
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Abstract— Anagen defluxion is an unusual cause of non-pruritic alopecia in many species. Two cases are described in horses, the onset coinciding with upper respiratory disease associated with pyrexia. Skin biopsies showed typical changes with follicles containing broken hairs of irregular shaft diameter. The alopecia resolved slowly without therapy. Résumé— L'effluvium anagène est une cause rare d'alopécie non prurigineuse dans de nombreuses espèces. Deux cas ont été obserés chez des chevaux. Le début a coincidé avec une atteinte des voies respiratoires supérieures associées à une fièvre. Les biopsies cutanées ont révélé des lésions caractéristiques: follicules contenant des poils cassés de diamètre iérrgulier. L'alopécie s'est progressivement résorbée sans traitement. Zusammenfassung— Anagen-Deflux ist eine ungewöhnliche Ursache für eine nicht pruritische Alopezie bei vielen Spezies. Beim Pferd werden zwei Fälle beschrieben, wobei der Beginn mit einer fieberhaften Erkrankung der oberen Atemwege zusammenfällt. Hautbiopsien zeigten typische Veränderungen mit Follikeln, die abgebrochene Haare mit unregelmäßigem Schaftdurchmesser enthielten. Die Alopezie heilte langsam ohne Therapie ab. Resumen La defluxión de la fase anagenica del pelo es una rara causa de alopecia de tipo no pruriginoso en una variedad de especies. En este artículo se describe el caso de dos caballos, en los cuales el punto más agudo de la enfermedad coincide con afeccion de las vías respiratorias altas acompañada de fiebre. Las biopsias cutáneas demostraron la presencia de cambios típicos en los folículos pilosos que contenían pelos rotos o de diámetro irregular. La alopecia se resolvió de manera lenta sin ningun tipo de terapia. 相似文献
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Stover J Bertozzi S Gutierrez JP Walker N Stanecki KA Greener R Gouws E Hankins C Garnett GP Salomon JA Boerma JT De Lay P Ghys PD 《Science (New York, N.Y.)》2006,311(5766):1474-1476
A strong, global commitment to expanded prevention programs targeted at sexual transmission and transmission among injecting drug users, started now, could avert 28 million new HIV infections between 2005 and 2015. This figure is more than half of the new infections that might otherwise occur during that period in 125 low- and middle-income countries. Although preventing these new infections would require investing about U.S.$122 billion over this period, it would reduce future needs for treatment and care. Our analysis suggests that it will cost about U.S.$3900 to prevent each new infection, but that this will produce a savings of U.S.$4700 in forgone treatment and care costs. Thus, greater spending on prevention now would not only prevent more than half the new infections that would occur from 2005 to 2015 but would actually produce a net financial saving as future costs for treatment and care are averted. 相似文献
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D. L. DOXEY ELSPETH M. MILNE C. P. MACKENZIE 《The Journal of small animal practice》1985,26(9):555-561
This paper describes the results of a retrospective survey of 43 cases of canine diabetes mellitus. The epidemiological data were in general agreement with previous surveys. Blood glucose, serum alkaline phosphatase, serum alanine aminotransferase, blood urea and serum cholesterol levels measured before starting treatment were found to be of limited value in forming a pre-treatment prognosis, although markedly raised values were a poor prognostic sign. 相似文献
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Hawkins EC Basseches J Berry CR Stebbins ME Ferris KK 《Journal of the American Veterinary Medical Association》2003,223(11):1628-1635
OBJECTIVE: To determine demographic, clinical, and radiographic features of bronchiectasis in dogs. DESIGN: Retrospective study. ANIMALS: 289 dogs identified through the Veterinary Medical Database (VMDB) and 27 dogs examined at the North Carolina State University Veterinary Teaching Hospital. PROCEDURE: Demographic characteristics of dogs identified through the VMDB were compared with characteristics of the entire population of dogs entered in the VMDB. Medical records of dogs examined at the teaching hospital were reviewed; the diagnosis was confirmed through review of thoracic radiographs. RESULTS: Analysis of data from the VMDB indicated that American Cocker Spaniels, West Highland White Terriers, Miniature Poodles, Siberian Huskies, English Springer Spaniels, and dogs > 10 years old had an increased risk of bronchiectasis. Among dogs examined at the teaching hospital, coughing was the most common clinical sign. There was evidence for excessive airway mucus but not hemorrhage. A variety of bacterial organisms were isolated from tracheal wash and bronchoalveolar lavage samples. On thoracic radiographs, cylindrical bronchiectasis, generalized disease, and right cranial lung lobe involvement were most common. Seven of 14 dogs for which follow-up radiographs were available did not have any progression of radiographic lesions. Median duration of clinical signs prior to diagnosis of bronchiectasis was 9 months (range, 1 day to 10 years). Median survival time was 16 months (range, 2 days to 72 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that despite substantial clinical abnormalities, dogs with bronchiectasis may survive for years. Certain purebred dogs and older dogs may have an increased risk of developing bronchiectasis. 相似文献