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排序方式: 共有59条查询结果,搜索用时 31 毫秒
1.
Mandy L. Wallace Janet A. Grimes Daniel J. Duffy Cameron Kindra Melissa MacIver Samantha Lin Valery F. Scharf Chad W. Schmiedt 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):617
A possible association between the development of nontraumatic, acquired inguinal hernias (NAIH) and perineal hernias (PH) has been postulated in adult dogs. The objective of this study was to evaluate the frequency of concurrent diagnosis of PH in dogs presented with NAIH and determine potential risk factors for concurrent PH and NAIH. Medical records of adult male dogs presented for NAIH to 4 hospitals between 2007 and 2017 were retrospectively reviewed. Twenty-one dogs with NAIH were included, 8 of which had concurrent PH. There were no significant differences between dogs with and without PH; however, among dogs with both conditions, intact dogs (8.1 ± 1.4 years) were younger than neutered dogs (11.7 ± 1.0 years; P = 0.007). Thirty-eight percent of male dogs presenting for NAIH had concurrent PH, indicating that these conditions commonly occur together. Dogs presenting for NAIH should be carefully evaluated for concurrent PH before surgical intervention. 相似文献
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Univalent fragments of gamma-globulin preparations from four individual rabbits were fractionated and the amino acid compositions of end fractions were compared. For amino acids with uncharged side chains, differences were consistently less than one residue per fragment of molecular weight 50,000. There were differences in the content of amino acids, other than glutamic acid, with charged side chains; these were in the direction expected on the basis of relative strength of adherence to carboxymethyl cellulose and electrophoretic mobility. Exclusive of any possible differences in amide, the total difference in charged groups was three to four residues per fragment. Sine the net charge of univalent fragments reflects that of the gamma-globulin molecule from which the fragments are derived, corresponding differences in composition may also exist among whole gamma-globulin molecules. 相似文献
4.
Highly conserved protective epitopes on influenza B viruses 总被引:1,自引:0,他引:1
C Dreyfus NS Laursen T Kwaks D Zuijdgeest R Khayat DC Ekiert JH Lee Z Metlagel MV Bujny M Jongeneelen R van der Vlugt M Lamrani HJ Korse E Geelen Ö Sahin M Sieuwerts JP Brakenhoff R Vogels OT Li LL Poon M Peiris W Koudstaal AB Ward IA Wilson J Goudsmit RH Friesen 《Science (New York, N.Y.)》2012,337(6100):1343-1348
Identification of broadly neutralizing antibodies against influenza A viruses has raised hopes for the development of monoclonal antibody-based immunotherapy and "universal" vaccines for influenza. However, a substantial part of the annual flu burden is caused by two cocirculating, antigenically distinct lineages of influenza B viruses. Here, we report human monoclonal antibodies, CR8033, CR8071, and CR9114, that protect mice against lethal challenge from both lineages. Antibodies CR8033 and CR8071 recognize distinct conserved epitopes in the head region of the influenza B hemagglutinin (HA), whereas CR9114 binds a conserved epitope in the HA stem and protects against lethal challenge with influenza A and B viruses. These antibodies may inform on development of monoclonal antibody-based treatments and a universal flu vaccine for all influenza A and B viruses. 相似文献
5.
Iahtasham Khan Lothar H. Wieler Mahboob Ahmad Butt Mandy C. Elschner Ashiq Hussain Cheema Lisa D. Sprague Heinrich Neubauer 《Journal of Equine Veterinary Science》2012
Glanders is a highly infectious and zoonotic disease of solipeds caused by Burkholderia mallei. Progressive loss of efficiency and fatal outcome resulted in massive economic losses, which forced veterinary authorities throughout the world to implement disease control measures; these measures included mass testing using the complement fixation test and/or malleinization, and the culling of positives. This led to the eradication of glanders from Western Europe and North America in the 1950s. However, in the last decade, the number of outbreaks in Asia and South America increased steadily, and glanders regained the status of a re-emerging transboundary disease. Pakistan has been an endemic country for the past 120 years, but concise data on the presence of disease are not available. A total of 533 serum samples were collected from draught equines, a suspected risk group for glanders, from various districts of Punjab in Pakistan. The complement fixation test and the highly sensitive Western blot technique were used for serodiagnosis. No animal (horse, mule, and donkey) was found to be positive for infection. Glanders seems to be restricted to remote, sporadic pockets of endemicity and may cause outbreaks after being introduced into naive populations by (asymptomatic) shedders. 相似文献
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Mandy Haggith Ravi Prabhu Happyson Mudavanhu Frank Matose Tendayi Mutimukuru Richard Nyirenda Wavell Standa-Gunda 《Small-Scale Forestry》2003,2(2):155-169
This paper explores the challenge of defining the scope of a systems model, emphasising three aspects: boundary, granularity
and conceptual scope. The significance of these is illustrated by reference to a model of land-use decisions made in villages
bordering on the Mafungautsi forest in Zimbabwe. The purpose of this model was to help policy players (Forestry Commission
staff, non-governmental organisations, researchers and local people) to understand the impact of policy interventions on local
people’s livelihoods. Scoping decisions that were made in building the Mafungautsi model were deliberately liberal, to encompass
the interests of all participants in the modelling process. These decisions now present a range of serious challenges: the
difficulty of model calibration, the computational expense of running simulations, and the difficulty for new users to understand
the model. Facilitators of modelling teams need to consider the serious implications of giving everyone what they want and
including all participants’ ideas in a model. In the long run, it may be better to be tough and reject many suggestions at
the outset. The former approach is unlikely to lead to a tractable model, while the latter may ultimately offer greater satisfaction
for all.
We are grateful to the UK’s Department for International Development (DFID) and the European Community for financial support
of this project. Thanks also to all of the ACM team who have contributed ideas on the process and content of the modelling
work and who make it fun to undertake collaborative research. Thanks also to the participants in the Zimbabwe FLAC workshops
for their input into the specification of the Mafungautsi model. Finally thanks to Robert Muetzelfeldt, Jasper Taylor, Jonathan
Massheder, Fergus Sinclair and Jerry Vanclay for helping us to ride on the FLORES bandwagon. 相似文献
8.
Chueh WC Falter C Abbott M Scipio D Furler P Haile SM Steinfeld A 《Science (New York, N.Y.)》2010,330(6012):1797-1801
Because solar energy is available in large excess relative to current rates of energy consumption, effective conversion of this renewable yet intermittent resource into a transportable and dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low conversion efficiencies, particularly with CO(2) reduction, as well as utilization of precious materials have limited the practical generation of solar fuels. By using a solar cavity-receiver reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO(2) and H(2)O, yielding CO and H(2), respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale and design rather than by chemistry. 相似文献
9.
Improving our knowledge of pre-anthropogenic landscapes is vital for understanding landscape-scale heterogeneity and for setting goals and objectives for ecological restoration. This is especially important in highly modified landscapes that contain few remnants of pre-impact ecosystems. This study aims to develop new methodology to improve understanding of historical vegetation, using the now-degraded inhabited highlands of the Galapagos Islands as a case study. Our multidisciplinary approach innovatively combines data from interviews with residents who were familiar with the vegetation before most degradation occurred with the more traditional sources of historical aerial photography and information from early explorer and scientist reports. We reconstruct historical vegetation across the landscape by mapping it in the year 1960 and discussing this map in the historical context of anthropogenic change. Our results confirm published vegetation types but also define some other types not previously described, and suggest much greater spatial, temporal and structural heterogeneity than commonly understood. This result can be used by Galapagos land managers to better match species assemblages with sites and plan restoration actions that will maximise resilience against the ongoing and future threats of climate change and species invasions. Our methodology can be applied in extensive areas of the world where the majority of anthropogenic disturbance to natural ecosystems has been within the past 60 years. 相似文献
10.
Schuler D Chevalier HJ Merker M Morgenthal K Ravanat JL Sagelsdorff P Walter M Weber K McGregor D 《Journal of toxicologic pathology》2011,24(3):149-162
Inhalation of vanadium pentoxide clearly increases the incidence of
alveolar/bronchiolar neoplasms in male and female B6C3F1 mice at all
concentrations tested (1, 2 or 4 mg/m3), whereas responses in F344/N
rats was, at most, ambiguous. While vanadium pentoxide is mutagenic in
vitro and possibly in vivo in mice, this does not
explain the species or site specificity of the neoplastic response. A nose-only
inhalation study was conducted in female B6C3F1 mice (0, 0.25, 1 and
4 mg/m3, 6 h/day for 16 days) to explore histopathological,
biochemical (α-tocopherol, glutathione and F2-isoprostane) and genetic (comet
assays and 9 specific DNA-oxo-adducts) changes in the lungs. No treatment
related histopathology was observed at 0.25 mg/m3. At 1 and
4 mg/m3, exposure-dependent increases were observed in lung
weight, alveolar histiocytosis, sub-acute alveolitis and/or granulocytic
infiltration and a generally time-dependent increased cell proliferation rate of
histiocytes. Glutathione was slightly increased, whereas there were no
consistent changes in α-tocopherol or 8-isoprostane F2α. There was no evidence
for DNA strand breakage in lung or BAL cells, but there was an increase in
8-oxodGuo DNA lesions that could have been due to vanadium pentoxide induction
of the lesions or inhibition of repair of spontaneous lesions. Thus, earlier
reports of histopathological changes in the lungs after inhalation of vanadium
pentoxide were confirmed, but no evidence has yet emerged for a genotoxic mode
of action. Evidence is weak for oxidative stress playing any role in lung
carcinogenesis at the lowest effective concentrations of vanadium pentoxide. 相似文献