A newly recognized blood group in domestic shorthair cats: the Mik red cell antigen     

Weinstein NM  Blais MC  Harris K  Oakley DA  Aronson LR  Giger U 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):287-292

BACKGROUND: Naturally occurring alloantibodies produced against A and B red cell antigens in cats can cause acute hemolytic transfusion reactions. Blood incompatibilities, unrelated to the AB blood group system, have also been suspected after blood transfusions through routine crossmatch testing or as a result of hemolytic transfusion reactions. HYPOTHESIS: Incompatible crossmatch results among AB compatible cats signify the presence of a naturally occurring alloantibody against a newly identified blood antigen in a group of previously never transfused blood donor cats. The associated alloantibody is clinically important based upon a hemolytic transfusion reaction after inadvertent transfusion of red cells expressing this red cell antigen in a feline renal transplant recipient that lacks this red cell antigen. METHODS: Blood donor and nonblood donor cats were evaluated for the presence of auto- and alloantibodies using direct antiglobulin and crossmatch tests, respectively, and were blood typed for AB blood group status. Both standard tube and novel gel column techniques were used. RESULTS: Plasma from 3 of 65 cats and 1 feline renal transplant recipient caused incompatible crossmatch test results with AB compatible erythrocytes indicating these cats formed an alloantibody against a red cell antigen they lack, termed Mik. The 3 donors and the renal transplant recipient were crossmatch-compatible with one another. Tube and gel column crossmatch test results were similar. CONCLUSIONS AND CLINICAL IMPORTANCE: The absence of this novel Mik red cell antigen can be associated with naturally occurring anti-Mik alloantibodies and can elicit an acute hemolytic transfusion reaction after an AB-matched blood transfusion.  相似文献   

Genetic consequences of low local tree densities - Implications for the management of naturally rare, insect pollinated species in temperate forests     

Urs Kamm  Felix Gugerli 《Forest Ecology and Management》2011,262(6):1047-1053

Early on, researchers of evolutionary biology recognised that heterogeneity in the mating environment is an important source of variation in mating patterns. Focusing on the mating environment, we assessed the effect of conspecific tree density on mating patterns in the naturally scattered forest tree Sorbus domestica L. In an area of more than 100 km², we mapped and genotyped all 189 adult trees and performed a paternity analysis on seeds produced by single mothers. Despite a self-incompatibility system, average selfing rate was 31.9%, but with high variation among mother trees. Over 70% of this variation was explained by local density of conspecifics (i.e. within a radius of 300 m), with isolated trees being more prone to selfing. While we detected high selfing rates in progeny, adult trees showed no signs of inbreeding. As almost all inbreeding in the offspring could be attributed to self-fertilisation, we hypothesise that there is strong selection against selfed individuals. The effective reproductive output of isolated trees, which mainly self, is therefore greatly reduced. These findings have important consequences for the management of naturally scattered, insect-pollinated temperate tree species, often belonging to the family of Rosaceae. For these species, local density of conspecifics should be maintained above a certain threshold (i.e. 0.05 trees/ha in S. domestica), to avoid negative fitness consequences from selfing.  相似文献   

Variable rate nitrogen fertilizer response in wheat using remote sensing     

Bruno Basso  Costanza Fiorentino  Davide Cammarano  Urs Schulthess 《Precision Agriculture》2016,17(2):168-182

Nitrogen (N) fertilizer application can lead to increased crop yields but its use efficiency remains generally low which can cause environmental problems related to nitrate leaching as well as nitrous oxide emissions to the atmosphere. The objectives of this study were to: (i) to demonstrate that properly identified variable rates of N fertilizer lead to higher use efficiency and (ii) to evaluate the capability of high spectral resolution satellite to detect within-field crop N response using vegetation indices. This study evaluated three N fertilizer rates (30, 70, and 90 kg N ha^?1) and their response on durum wheat yield across the field. Fertilizer rates were identified through the adoption of the SALUS crop model, in addition to a spatial and temporal analysis of observed wheat grain yield maps. Hand-held and high spectral resolution satellite remote sensing data were collected before and after a spring side dress fertilizer application with FieldSpec, HandHeld Pro^® and RapidEye?, respectively. Twenty-four vegetation indices were compared to evaluate yield performance. Stable zones within the field were defined by analyzing the spatial stability of crop yield of the previous 5 years (Basso et al. in Eur J Agron 51: 5, 2013). The canopy chlorophyll content index (CCCI) discriminated crop N response with an overall accuracy of 71 %, which allowed assessment of the efficiency of the second N application in a spatial context across each management zone. The CCCI derived from remotely sensed images acquired before and after N fertilization proved useful in understanding the spatial response of crops to N fertilization. Spectral data collected with a handheld radiometer on 100 grid points were used to validate spectral data from remote sensing images in the same locations and to verify the efficacy of the correction algorithms of the raw data. This procedure was presented to demonstrate the accuracy of the satellite data when compared to the handheld data. Variable rate N increased nitrogen use efficiency with differences that can have significant implication to the N₂O emissions, nitrate leaching, and farmer’s profit.  相似文献   

Reaction of thiometon and disulfoton with reduced sulfur species in simulated natural environment     

Gan Q  Jans U 《Journal of agricultural and food chemistry》2006,54(20):7753-7760

The reactions of thiometon and its ethyl analogue, disulfoton, with reduced sulfur species [e.g., bisulfide (HS-), polysulfide (S(n)2-), thiophenolate (PhS-), and thiosulfate (S2O3(2-))] were examined in well-defined aqueous solutions under anoxic conditions. The role of reduced sulfur species was investigated in the abiotic degradation of thiometon and disulfoton. Experiments at 25 degrees C demonstrated that HS-, S(n)2-, PhS-, and S2O3(2-) promoted the degradation of thiometon to a great extent while only S(n)2- and PhS- showed a small accelerating effect in the degradation of disulfoton. Reactions were monitored at varying concentrations of reduced sulfur species to obtain the second-order rate constants. The reactivity of the reduced sulfur species decreased in the following order: S(n)2- > PhS- > HS- approximately S2O3(2-). Transformation products were confirmed by standards or characterized by gas chromatography mass spectrometry. The results illustrate that multiple pathways occur in the reactions with reduced sulfur species, among which the nucleophilic attack at the alpha-carbon of the alkoxy group was the predominant pathway. Activation parameters of the reaction of thiometon and disulfoton with HS- were also determined from the measured second-order rate constants over a temperature range. DeltaH( not equal) values indicated that the reactivity of thiometon toward HS- was much greater than for disulfoton. Nucleophilic attack at the alkoxy group was more important for thiometon than disulfoton. When the measured second-order rate constants at 25 degrees C are multiplied by [HS-] and Sigma[S(n)2-] reported in saltmarsh porewaters, predicted half-lives show that reduced sulfur species present at environmentally relevant concentrations may present an important sink for thiometon in coastal marine environments.  相似文献   

Feline leukocyte adhesion (CD18) deficiency caused by a deletion in the integrin β2 (ITGB2) gene          下载免费PDF全文

Thomas R. Bauer Jr.  Suzanne M. Pratt  Christina M. Palena  Karthik Raj  Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(3):391-400

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