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41.
Clinical features of 36 dogs with histologically confirmed fibrocartilaginous embolism (FCE) were contrasted with those of 26 dogs in which FCE was suspected based on characteristic clinical findings and the absence of compressive spinal cord disease on myelography. Dogs with confirmed and suspected FCE were of similar signalment, and had acute, nonprogressive dysfunction, often associated with trauma or exercise. The "suspected" group included fewer giant breeds and more often had asymmetric lesions, intact nociception, and upper motor neuron involvement. Dog size and severity of clinical signs probably contributed to owners choosing euthanasia in dogs with confirmed lesions. Accordingly, data from such patients may be skewed relative to these clinical features. J Vet Intern Med 1996;10:241–245. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   
42.
OBJECTIVE: To determine the accuracy of asymmetry indices of ground reaction forces (GRF) for diagnosis of hind limb lameness in dogs. ANIMALS: 36 healthy dogs and 13 dogs with naturally acquired cranial cruciate ligament rupture or hip dysplasia. PROCEDURES: Lameness for affected dogs ranged from not detectable to minor and constant. While dogs trotted on an instrumented treadmill, GRF variables were recorded and analyzed with asymmetry indices. Each index was tested for its ability to discriminate between healthy and affected dogs. Combinations of several indices were also assessed. RESULTS: Vertical force variables had better accuracy than craniocaudal force variables. Peak vertical force was the most accurate variable. Partial asymmetry during trotting was detected in healthy dogs. A multivariate approach that used peak vertical force and maximal rising slope yielded the optimum combination to distinguish between healthy and affected dogs. In addition, sensitivity of 92% or specificity of 95% may be achieved with 2 cutoff values while simultaneously maintaining specificity or sensitivity, respectively, at > 85%. CONCLUSIONS AND CLINICAL RELEVANCE: Asymmetry indices of GRFs were accurate for detection of hind limb lameness in dogs. This is particularly relevant for study designs in which only a single gait evaluation is possible.  相似文献   
43.
Taro (Colocasia esculenta) is the tropical root crop species featuring the greatest flavonoids diversity. Their quantification is important for breeding programmes focusing on biofortification. This study aims at developing an HPTLC protocol to compare the flavonoids fingerprints of more than 1800 hybrids belonging to 24 full‐sib families and to select genotypes with high levels of antioxidants. Twenty different chemical markers were identified based on bands Rf and colour. Flavonoids differ among individuals both quantitatively and qualitatively. Marker ‘A’ yielded the strongest antioxidant response to DPPH, equivalent to the one with quercetin pure standard. Overall, 377 high flavonoids content (HFC) hybrids were selected from 14 different families. The mean corm weight of HFC hybrids always appeared higher than the mean corm weight of the family they belong to. This method allows unambiguous selection of HFC hybrids. It also contributes to taro genetic improvement for nutritional value and access to new markets and to strengthen corm tolerance to pests and diseases. It could be applied to other tropical root crop species.  相似文献   
44.

• Introduction   

Stem taper equations have been widely used for volume estimation to varied top diameter limits or for biomass calculations. However, their main drawback is that specific calibration is often necessary for each species or clone, and accounting for genetic and environmental effects is often a challenge.  相似文献   
45.
Gas-phase, water-soluble components of cigarette smoke cause delayed fibrin self-assembly and prevent fibrin cross-linking by inactivation of factor XIIIa (plasma transglutaminase). These anticoagulant properties of smoke are demonstrable in plasma, suggesting they play a role in the pathophysiology of smoking.  相似文献   
46.
Biological nitrogen fixation in Lake Erie   总被引:4,自引:0,他引:4  
Biological nitrogen fixation, as determined by acetylene reduction, occurs in Lake Erie. Fixation potential by blue-green algae in situ in water and by bacteria in collected sediments was demonstrated. Nitrogen-fixing activity occurred from June through November suggesting that it is significant over the extremes of seasonal variation in light, temperature, and nutrients.  相似文献   
47.
Alkanes adopt extended conformations in solution that minimize steric interactions and maximize surface area. Folding can reduce the amount of hydrophobic surface exposed to solvent, but sterically unfavorable gauche interactions result. However, we found that the alkyl chains of two common surfactants in aqueous solution adopt helical conformations when bound within a synthetic receptor. The receptor recognizes the helical alkane better than the extended conformation, even though 2 to 3 kilocalories per mole of strain is introduced. The proper filling of space and burial of hydrophobic surface drive the molecular recognition between the receptor and the coiled alkane.  相似文献   
48.
Floc-forming bacteria isolated from Lake Erie adsorb and concentrate aldrin from colloidal dispersion so that the settling of the bacterial flocs removes aldrin from the water phase. Contemporary sediments forming in Lake Erie contain aldrin and could adsorb more. The sediments consist of a conglomerate floc of bacteria, diatoms, and inorganic and detrital particles. Flocculent bacteria also adsorb microparticulates, and this adsorption capacity represents a mechanism for sediment formation and for the removal of suspended particles including aldrin from the water column.  相似文献   
49.
Deep Impact observations by OSIRIS onboard the Rosetta spacecraft   总被引:1,自引:0,他引:1  
The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging system) onboard the European Space Agency's Rosetta spacecraft observed comet 9P/Tempel 1 for 17 days continuously around the time of NASA's Deep Impact mission. The cyanide-to-water production ratio was slightly enhanced in the impact cloud, compared with that of normal comet activity. Dust particles were flowing outward in the coma at >160 meters per second, accelerated by the gas. The slope of the brightness increase showed a dip about 200 seconds after the impact. Dust Afrho values before and long after the impact confirm the slight decrease of cometary activity. The dust-to-water mass ratio was much larger than 1.  相似文献   
50.
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