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排序方式: 共有137条查询结果,搜索用时 31 毫秒
71.
P A Pryor B L Hart M J Bain K D Cliff 《Journal of the American Veterinary Medical Association》2001,219(12):1709-1713
OBJECTIVE: To evaluate effects of environmental management alone on marking frequency in cats with urine marking and to obtain demographic data on cats with urine marking and data on owner-perceived factors that contributed to urine marking behavior. DESIGN: Single-intervention study. ANIMALS: 40 neutered male and 7 spayed female cats. PROCEDURE: During a 2-week baseline phase, owners maintained a daily record of the number of urine marks. This phase was followed by a 2-week environmental management phase during which owners cleaned recently deposited urine marks daily, scooped waste from the litter box daily, and changed the litter and cleaned the litter box weekly while continuing to record urine marks. RESULTS: Male cats and cats from multicat households were significantly overrepresented, compared with the general pet cat population in California. The most commonly mentioned causative factors for urine marking were agonistic interactions with other cats outside or inside the home. Environmental management procedures resulted in an overall reduction in urine marking frequency. Among cats that marked > or = 6 times during the baseline phase, females were significantly more likely to respond to treatment (> or = 50% reduction in marking frequency) than were males. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that male cats and cats from multicat households are more likely to exhibit urine marking behavior than females and cats from single-cat households. Results also suggest that attention to environmental and litter box hygiene can reduce marking frequency in cats, regardless of sex or household status of the cats, and may come close to resolving the marking problem in some cats. 相似文献
72.
Chemical and mineralogical weathering rates and processes in an upland granitic till catchment in Scotland 总被引:1,自引:0,他引:1
Weathering in an upland granitic till catchment receiving an intermediate level of acidic deposition has been studied by chemical and mineralogical analyses of soil profiles and chemical analysis of precipitation and streamwater. Long-term weathering rates for base cations calculated from analyses of soil profile horizons using Zr as an internal, immobile, index element are similar for alpine podzols and peaty podzols and are 2–3 meq.m–2.a–1 for Ca and Mg, and 10–11 meq.m–2.a–1 for K and Na. The high loss of Na is associated with the weathering of oligoclase, particularly in the coarse sand fraction. Loss of K is related to weathering of K-feldspar and micas. Current weathering rates for base cations calculated from input-output budgets are higher than long-term rates by factors of 12, 8 and 3 for Ca, Mg and Na, but lower by a factor of 7 for K probably due to biomass uptake. The higher current overall loss of base cations may be due to increased rates of weathering in recent times but this is not conclusive as there are large uncertainties inherent in both methods of estimation. 相似文献
73.
S. J. Langan M. E. Hodson D. C. Bain R. A. Skeffington M. J. Wilson 《Water, air, and soil pollution》1995,85(3):1075-1081
The release of base cations from chemical weathering is the fundamental process by which base cations lost through leaching or biological uptake are replenished. Soils with a high content of easily weatherable minerals will, in general, be readily able to neutralise incoming acidity and satisfy biological requirements through this supply of base cations from weathering. Conversely those soils with a low content of such minerals will be unable to buffer acid inputs or meet biological demands and will be vulnerable to acidification. It is evident therefore that an accurate estimate of the rate of chemical weathering is a prerequisite for any assessment of ecosystem sensitivity to acidification. The principal methods by which these calculations are made can be grouped into those based on element depletion in soil horizons calculated against a conservative element reference, catchment fluxes, laboratory studies and the use of mathematical models which utilise data from each of these sources. A review of the published data has been undertaken to determine if a systematic variation in weathering rates can be observed for a range of parent materials and/or methods used. Variations of 0.03–0.8 keq ha?1yr?1 for K+, 0.0–1.0 keq ha?1yr?1 for Na+, 0.01–1.39 keq ha?1yr?1 for Mg2+ and 0.0–5.8 keq ha?1yr?1 for Ca2+ were found. In general individual cation weathering rates determined from catchment fluxes, and also the model MAGIC, are dominated by Ca2+, with Mg2+ being the next most significant release rate. However it has not been possible to determine any other systematic variations due to the limited number of sites where weathering rate has been determined by more than one method. 相似文献
74.
E L McMonagle S Taylor H van Zuilekom L Sanders N Scholtes L J Keanie C A Hopkins N A Logan D Bain D J Argyle D E Onions V E Schijns L Nicolson 《Equine veterinary journal》2001,33(7):693-698
Interleukin-12 (IL-12) is a key cytokine in the development of cell-mediated immune responses. Bioactive IL-12 is a heterodimeric cytokine composed of disulphide linked p35 and p40 subunits. The aim of this study was to verify biologically activity of the products expressed from equine interleukin-12 (IL-12) p35 and p40 cDNAs and to establish whether equine IL-12 could be expressed as a p35/p40 fusion polypeptide, as has been reported for IL-12a of several mammalian species. We report production of equine IL-12 through expression of p35 and p40 subunits in mammalian and insect cells and of a p35:p40 fusion polypeptide in mammalian cells. Conditioned medium recovered from cultures transiently transfected with constructs encoding equine p35 and p40 subunits or single chain IL-12 enhanced IFN-gamma production in cells derived from equine lymph nodes. Preincubation of IFN-gamma inducing preparations with anti-p40 monoclonal antibody resulted in a significant decrease in IFN-gamma induction capacity. Medium recovered from p35 and p40-expressing baculovirus infected cultures enhanced target cell IFN-gamma production and proliferation. Experimental studies in mice and other animals have revealed a therapeutic benefit of IL-12 in cancer, inflammatory and infectious disease and an adjuvant effect in prophylactic regimes. Production of a bioactive species-specific IL-12 is a first step towards an investigation of its potential application in equine species. 相似文献
75.
Summary Several clones from a potato breeding programme at the Scottish Crop Research Institute (SCRI) produced acceptable (pale)
coloured fry products after five months' storage at 4°C. Chemical analysis of tuber samples taken at five-week intervals during
storage at 4°C and 10°C gave a substantial variation in glucose, fructose and sucrose concentrations among the 22 clones examined.
Several unnamed SCRI clones showed little accumulation of reducing sugars when stored at 4°C. In marked contrast, the cultivars
Record and Pentland Dell, currently the most widely used cultivars for fry processing in the UK, accumulated far greater levels
of sugar during low temperature storage. Glucose concentration proved more important than fructose concentration in determining
fry colour. Clones with the lowest concentrations of glucose after storage at 4°C also showed lowest concentrations when stored
at 10°C. These results are in agreement with previous reports on the predictive value of glucose levels at harvest, but this
is the first identification of such low temperature, low sweetening variants in agronomically adapted clones of the cultivated
tetraploid potato. 相似文献
76.
Otranto D Brianti E Dantas-Torres F Weigl S Latrofa MS Gaglio G Cauquil L Giannetto S Bain O 《Veterinary parasitology》2011,182(2-4):221-229
Dermal microfilariae found in a dog from Sicily, Italy, were characterized morphologically and genetically and differentiated from those of all the other blood microfilariae commonly found in dogs. In particular, the microfilariae were short (mean length of 186.7 μm), presented a body flattened dorso-ventrally and a rounded head, bearing a tiny cephalic hook. The genetic identity of microfilariae herein studied was also assessed by molecular amplification, sequencing and analyzing of multiple ribosomal ITS-2 and mitochondrial (cox1 and 12S) target genes. Both morphologic and genetic characterization as well as the molecular phylogenetic history inferred using sequences of a barcoding dataset were concordant in supporting the identification of Cercopithifilaria at the genus level. Surprisingly, microfilariae here examined were well distinct from Cercopithifilaria grassii (Noè, 1907), from northern Italy, and resembled those of a species described in Brazil, Cercopithifilaria bainae Almeida & Vicente, 1984. This paper provides evidence for the existence of a Cercopithifilaria species infesting a dog from Sicily and also presents a PCR protocol on skin samples as a tool for further epidemiological studies, which could provide evidence on the aetiology and the natural history of this filarial species. 相似文献
77.
J. E. Cottrell C. M. Duffus L. Paterson G. R. Mackay M. J. Allison H. Bain 《Potato Research》1993,36(2):107-117
Summary Reducing sugar content, and activities of three starch hydrolysing enzymes, alpha-amylase, beta-amylase and debranching enzyme
were measured over several months in tubers of five cultivars stored at 4°C or 10°C. Cultivars differed in their sensitivity
to storage temperature. Reducing sugar content of tubers and the activities of three starch hydrolysing enzymes increased
sharply during the first weeks of storage at 4°C. At 10°C, reducing sugar content, and the activity of the three enzymes remained
constant or increased only slightly.
Deceased. 相似文献
78.
Recent research exposing environmental and social externalities of biofuels has undermined the earlier national consensus that they would provide climate mitigation and rural development benefits, but support for ethanol remains strong in Iowa. The objective of this paper is to understand how stakeholder groups in Iowa have framed the benefits and risks associated with ethanol’s impact on the local economy and environment. Our case study draws on in-depth, semi-structured interviews conducted with key informants from agricultural organizations, environmental organizations, and government departments in the state. We find that in Iowa, widespread support for ethanol production exists among government, energy, and farm groups, and that they frame ethanol production as economically beneficial to rural communities and agriculture, while minimizing the possibility of associated environmental risks. Although participants from environmental organizations in Iowa express apprehension about the environmental impacts of expanded corn ethanol production, their unease is muted in relation to economic benefits and in relation to other environmental issues, and few have publicly voiced their concerns. To understand these findings, we draw from the environmental sociology literature that examines the role of powerful natural resource interests in framing the importance of resource extraction and commodity production to community identity and economy and in delegitimizing and naturalizing associated environmental issues and problems. We argue that powerful natural resource interests in Iowa both naturalize environmental problems related to ethanol production and engage in diversionary reframing to emphasize the economic benefits while minimizing or rejecting the potential environmental risks. 相似文献
79.
Md. Shahjahan Md. Helal Uddin Victor Bain Md. Mahfuzul Haque 《Fish physiology and biochemistry》2018,44(5):1309-1318
The increase of water temperature due to global warming is a great concern of aquaculturists and fishery biologists. In the present study, we examined the effects of high temperature on hematological parameters and blood glucose levels in striped catfish, Pangasianodon hypophthalmus exposed to three temperature conditions (28, 32, and 36 °C) for 7 days. Fish were sacrificed at days 1, 3, and 7. Erythroblasts (Ebs), erythrocytic cellular abnormalities (ECA), and erythrocytic nuclear abnormalities (ENA) were assayed using peripheral erythrocytes of the sampled fishes. Hemoglobin (Hb) and red blood cell (RBC) significantly (P?<?0.05) decreased at 36 °C after 3 and 7 days of exposure, whereas white blood cell (WBC) showed opposite scenario. Blood glucose levels significantly (P?<?0.05) increased at 36 °C on day 3. Frequencies of Ebs, ECA, and ENA were found to be elevated at increased temperature. Differential leucocytes count showed significant increases in neutrophil and decreases in lymphocytes in the highest temperature (36 °C). Dissolved oxygen decreased and free CO2 increased significantly (P?<?0.05) with increasing temperature, while the pH and total alkalinity of the water were almost unchanged throughout the study period. Therefore, the present study demonstrated that striped catfish feel better adaptation at 28 and 32 °C, while high temperature 36 °C is likely stressful to this fish species. 相似文献
80.
The r?le of infection in infertility in the thoroughbred mare 总被引:1,自引:0,他引:1
A M Bain 《The Veterinary record》1966,78(5):168-173