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981.
The Fusarium species are a group of saprophytic fungal organisms that are occasionally the cause of opportunistic infections in humans and animals. Central nervous system disease associated with a Fusarium species is most commonly described in horse, resulting in equine leukoencephalomalacia. This report describes a 2-year-old, spayed, female German Shepherd Dog with meningoencephalitis secondary to infection with Fusarium spp. Meningoencephalitis in dogs secondary to a species of Fusarium has not been previously reported. The diagnosis was made based on the histopathologic examination of brain tissues postmortem and special immunohistochemical stains specific for Fusarium solani. The clinical signs in this dog were indicative of multifocal brain disease and included seizures and a paradoxical vestibular syndrome. The clinical findings, diagnostic and histopathologic test results, and the comparative characterizations of other disseminated fungal diseases, especially aspergillosis, are described.  相似文献   
982.
983.
    
A study on the occurrence of coccidiosis and distribution of Eimeria species in dead chickens 1-60 days of age, at Kombolcha Poultry Multiplication and Research Center (KPMRC), Ethiopia was conducted from November 2002 to April 2003. Out of the 965 dead birds, 370 (38.34%) were found to have clinical coccidiosis. The Eimeria species identified in this study were Eimeria brunetti, E. tenella, E. acervulina and E. necatrix with prevalence rates of 45.3%, 40.8%, 9.7%, and 4.1%, respectively. In the current study, E. brunetti was reported for the first time in Ethiopia. It was noted that clinical coccidioisis was more prevalent in those between 5 and 6 weeks of age. A statistically significant difference (p < 0.05) was observed in clinical coccidiosis prevalence among the different age groups studied. Various managerial problems that are associated with this high prevalence of clinical coccidiosis are identified and appropriate control strategies are recommended.  相似文献   
984.
985.
Homoploid hybrid speciation in an extreme habitat   总被引:1,自引:0,他引:1  
According to theory, homoploid hybrid speciation, which is hybrid speciation without a change in chromosome number, is facilitated by adaptation to a novel or extreme habitat. Using molecular and ecological data, we found that the alpine-adapted butterflies in the genus Lycaeides are the product of hybrid speciation. The alpine populations possess a mosaic genome derived from both L. melissa and L. idas and are differentiated from and younger than their putative parental species. As predicted, adaptive traits may allow for persistence in the environmentally extreme alpine habitat and reproductively isolate these populations from their parental species.  相似文献   
986.
  总被引:7,自引:0,他引:7  
Water samples collected once a week from early April 1996 to the end of August 1996 from four sites on the Shinano River in Japan were analyzed for pesticides and their metabolites using a gas chromatograph-mass spectrometer. Among the total of 53 chemicals found, 22 were herbicides, 15 were insecticides, 11 were fungicides, and 5 were metabolites. The concentrations of chemicals found ranged from 3 ng/L (bromobutide) to 8200 ng/L (isoprothiolane). Herbicides were found primarily during May and June at all four sites. Insecticides and fungicides were found primarily during July and August at all four sites. The presence of pesticides in the river water correlated with the time of pesticide application to the rice fields near the river.  相似文献   
987.
    
Advances in the deposition process have led to dramatic improvements in the electronic properties of polycrystalline diamond films produced by chemical vapor deposition (CVD). It is now possible to produce CVD diamond with properties approaching those of IIa natural diamonds. The combined electron-hole mobility, as measured by transient photoconductivity at low carrier density, is 4000 square centimeters per volt per second at an electric field of 200 volts per centimeter and is comparable to that of the best single-crystal IIa natural diamonds. Carrier lifetimes measured under the same conditions are 150 picoseconds for the CVD diamond and 300 picoseconds for single-crystal diamond. The collection distance at a field of 10 kilovolts per centimeter is 15 micrometers for the CVD diamond as compared to 30 micrometers for natural diamonds. The electrical qualities appear to correlate with the width of the diamond Raman peak. Also, although the collection distance at the highest fields in the films nearly equals the average grain size, there is no evidence of deleterious grain boundary effects.  相似文献   
988.
During the period July 1977 to June 1984, specimens from 1402 broiler chicken flocks were submitted to the Veterinary Research Institute, Victoria, Australia for investigation of morbidity, mortality and, or, poor performance. A total of 19,450 post mortem examinations, as well as numerous ancillary tests, were performed. The findings on these flocks are presented and the consequences of some particular diseases noted.  相似文献   
989.
    
Precipitation events were collected during the period from October 1996 to April 1997 from two sites in the city of Amman, Jordan. The samples were analyzed for major cations (Na+, K+, Ca2+, Mg2+ and NH4+), major anions (F-, Cl-, NO3- and SO42-), in addition to heavy metals (Cu2+, Cd2+, Zn2+, and Pb2+). High levels of Ca2+ and SO42- were observed. The results were comparable with some regional values and they indicate that about 58% of Na+ and Cl- are of marine origin, while Ca2+, K+ and a large fraction of SO42- are of soil dust origin. Heavy metals were detectable in most of the samples, zinc showed the highest concentrations. Significant correlation was obtained between zinc and lead, which may indicate automobile emission source.  相似文献   
990.
An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice.  相似文献   
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