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排序方式: 共有205条查询结果,搜索用时 31 毫秒
41.
Eva van Gorsel Nicolas Delpierre Ray Leuning Andy Black J. William Munger Steven Wofsy Marc Aubinet Christian Feigenwinter Jason Beringer Damien Bonal Baozhang Chen Jiquan Chen Robert Clement Kenneth J. Davis Ankur R. Desai Danilo Dragoni Sophia Etzold Thomas Grünwald Lianhong Gu Bernhard Heinesch Lucy R. Hutyra Wilma W.P. Jans Werner Kutsch B.E. Law Monique Y. Leclerc Ivan Mammarella Leonardo Montagnani Asko Noormets Corinna Rebmann Sonia Wharton 《Agricultural and Forest Meteorology》2009,149(11):1919
Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (FC) and change in storage (FS) of CO2 in the few hours after sundown. The sum of FC and FS reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration RRmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of Fc + Fs extrapolated to zero light, RLRC, and (3) with a detailed process-based forest ecosystem model, Rcast. At most sites respiration rates estimated using the u*-filter, Rust, were smaller than RRmax and RLRC. Agreement of our approach with independent measurements indicates that RRmax provides an excellent estimate of nighttime ecosystem respiration. 相似文献
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Dilini N. Thilakaratne Monique N. Mayer Valerie S. MacDonald Marion L. Jackson Brenda R. Trask Beverly A. Kidney 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(1):79-84
Polymerase chain reaction (PCR) assays for the immunoglobulin and T-cell receptor genes were utilized to determine phenotype and clonality from lymph node cytologic smears and peripheral blood lymphocytes from 10 dogs with lymphoma, before chemotherapy and during remission. Results were compared with those from 13 dogs with a cytologic diagnosis of lymph node hyperplasia. Clonality was identified in 7 of the lymphomas on the basis of either lymph node cytology or peripheral blood lymphocytes before treatment. No lymph node hyperplasia samples were clonal. In 6 of the dogs with lymphoma, clonality was demonstrated during clinical remission. Detection of PCR clonality during clinical remission is an effective means of identifying minimal residual disease in canine lymphoma and thus additional work is warranted to determine if molecular remission is prognostic or predictive for outcome in well-controlled and well-defined lymphoma subtypes. 相似文献
44.
Hordeaux J Deniaud J Bemelmans I Bertrand L Moreau S Amiaud J Wyers M Cherel Y Colle MA 《Veterinary pathology》2011,48(3):616-626
Mucopolysaccharidosis (MPS) types I and VII are inborn errors of metabolism caused by mutation of enzymes involved in glycosaminoglycan catabolism, which leads to intralysosomal accumulation of glycosaminoglycans. In children, severe forms of MPS I and VII are characterized by somatic and neurologic manifestations, including a poorly understood hearing loss. The purpose of this study is to describe the age-related histopathologic changes of the ear in spontaneous canine models of MPS I and VII. Pathologic changes in the ear were assessed in MPS I and VII dogs ranging from 1.6 to 9.3 months of age. Paraffin-embedded sections of the whole ear and Epon-embedded semithin sections of the cochlea were examined. The following lesions were blindly scored in the middle and inner ear: inflammation, cells vacuolization, thickening of osseous and membranous structures, perivascular vacuolated macrophages infiltration, and bone resorption. All dogs had lysosomal storage within cells of tympanic membrane, ossicles, tympanic bone and mucosa, cochlear bone, spiral ligament, limbus, and stria vascularis. The MPS I dogs mainly had progressive cochlear lesions. The MPS VII dogs had severe and early middle ear lesions, including chronic otitis media and bone resorption. The MPS I dog only partially recapitulates the pathology seen in humans; specifically, the dog model lacks inflammatory middle ear disease. In contrast, the MPS VII dog has severe inflammatory middle ear disease similar to that reported in the human. In conclusion, the canine MPS VII model appears to be a good model to study MPS VII-related deafness. 相似文献
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Celina Y. Morimoto Monique N. Mayer Narinder Sidhu Rachel Bloomfield Cheryl L. Waldner 《Veterinary and comparative oncology》2020,18(2):199-205
Sources of residual setup error after image guidance include image localization accuracy, errors associated with image registration, and inability of some treatment couches to correct submillimeter translational errors and/or pitch and roll errors. The purpose of this experimental study was to measure setup error after image‐guided correction of the canine intracranial region, using a four degrees‐of‐freedom couch capable of 1 mm translational moves. Six cadaver dogs were positioned 45 times as for clinical treatment using a vacuum deformable body cushion, a customizable head cushion, a thermoplastic mask and an indexed maxillary plate with a dental mould. The location of five fiducial markers in the skull bones was compared between the reference position and after megavoltage (MV), kilovoltage (kV) and cone‐beam computed tomography (CBCT)‐guided correction using orthogonal kV images. The mean three‐dimensional distance vectors (3DDV) after MV, kV and CBCT‐guided correction were 1.7, 1.5 and 2.2 mm, respectively. All values were significantly different (P < .01). The 95th percentiles of the 3DDV after online MV, kV and CBCT‐guided correction were 2.8, 2.6 and 3.6 mm, respectively. Residual setup error in the clinical scenario examined was on the order of millimetres and should be considered when choosing PTV margins for image‐guided radiation therapy of the canine intracranial region. 相似文献
47.
Monique Soro Fidèle Tiendrébéogo Justin S. Pita Edwig T. Traoré Koussao Somé Ezechiel B. Tibiri James B. Néya J. Musembi Mutuku Jacques Simporé Daouda Koné 《Plant pathology》2021,70(9):2207-2216
Surveys were conducted in 2016 and 2017 across the main cassava-growing regions of Burkina Faso to assess the status of cassava mosaic disease (CMD) and to determine the virus strains causing the disease, using field observation and phylogenetic analysis. CMD incidence varied between regions and across years but was lowest in Hauts-Bassins (6.0%, 2016 and 5.4%, 2017) and highest in Centre-Sud (18.5%, 2016) and in Boucle du Mouhoun (51.7%, 2017). The lowest CMD severity was found in Est region (2.0) for both years and the highest in Sud-Ouest region (3.3, 2016) and Centre-Sud region (2.8, 2017). The CMD infection was primarily associated with contaminated cuttings in all regions except in Hauts-Bassins, where whitefly-borne infection was higher than cuttings-borne infection in 2016. PCR screening of 687 samples coupled with sequence analysis revealed the presence of African cassava mosaic-like (ACMV-like) viruses and East African cassava mosaic-like (EACMV-like) viruses as single infections at 79.5% and 1.1%, respectively. Co-infections of ACMV-like and EACMV-like viruses were detected in 19.4% of the tested samples. In addition, 86.7% of the samples positive for EACMV-like virus were found to be positive for East African cassava mosaic Cameroon virus (EACMCMV). Phylogenetic analysis revealed the segregation of cassava mosaic geminiviruses (CMGs) from Burkina Faso into three clades specific to ACMV, African cassava mosaic Burkina Faso virus (ACMBFV), and EACMCMV, confirming the presence of these viruses. The results of this study show that EACMCMV occurrence may be more prevalent in Burkina Faso than previously thought. 相似文献
48.
Jocelyne Delisle Jean Amiot Germain-J. Brisson Monique Lacroix 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(2-3):173-177
Although the efficiency ratio (PER) of vegetable proteins can be improved by supplementation with the limiting free amino acids, the digestibility of these proteins remains lower than that of animal proteins. The digestibility of a rapeseed protein concentrate measured in rats was improved from a value of 81 to 87% by water solubilization and ammonium sulfate precipitation. 2S and 12S fractions were also prepared from a rapeseed protein concentrate by a method based on differences of solubility in ammonium sulfate solutions. Protein digestibility of the rapeseed protein concentrate was found to be 82%, as compared to 87% and 89% for 2S and 12S fractions. A reduction of protein efficiency ratio was also recorded and was found to result from losses in amino acids. 相似文献
49.
J. Barrat Marie Jos Barrat Monique Picard M. F. A. Aubert collaboration technique Y. Gerard Chantal Patron Josiane Ambert B atrice Quillou 《Comparative immunology, microbiology and infectious diseases》1988,11(3-4):207-214
Mouse inoculation test (MIT) is a highly sensitive test for rabies diagnosis but slow and expensive. To detect rabies virus an in vitro technique using Neuro 2a cell culture (CC) was compared with MIT in two laboratories.
In one laboratory, CC appeared to be on the whole more sensitive than MIT, nevertheless MIT was the only one to detect some positive samples. In the other laboratory, MIT was more sensitive. These results justify the use of CC for epidemiological diagnosis but emphasize the interest of MIT (the reference technique) for special cases. 相似文献
50.