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11.
Analysis of the interlayer infrared conductivity of cuprate high-transition temperature superconductors reveals an anomalously large energy scale extending up to midinfrared frequencies that can be attributed to formation of the superconducting condensate. This unusual effect is observed in a va- riety of materials, including Tl2Ba2CuO6+x, La2-xSrxCuO4, and YBa2Cu3O6.6, which show an incoherent interlayer response in the normal state. Midinfrared range condensation was examined in the context of sum rules that can be formulated for the complex conductivity. One possible interpretation of these experiments is in terms of a kinetic energy change associated with the superconducting transition.  相似文献   
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Sheep were immunised with Corynebacterium pseudotuberculosis toxoid formulated as a monocomponent vaccine with aluminium adjuvant or in combination with 5 clostridial antigens, and also in the combined form with sodium selenate. Immunised and control sheep were experimentally infected 16 days after vaccination and slaughtered and inspected after a further 3 months to determine their resistance to infection. All 3 vaccines afforded an equal and high level of protection; 91% of vaccinated sheep exhibiting no lesions of caseous lymphadenitis compared with 51.5% affected sheep in the control group. Average lesion counts were 1.2 per affected vaccinated sheep and 4.5 per affected control sheep. Antitoxin responses to the clostridial toxoids incorporated in the combined vaccines were not affected by inclusion of the C pseudotuberculosis toxoid or the sodium selenate.  相似文献   
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An epidemiologic study was conducted by use of the Veterinary Medical Data Base to investigate risk factors for blastomycosis in dogs. From January 1980 through June 1990, 971 cases of blastomycosis in dogs from 22 North American veterinary teaching hospitals were identified. Of these cases, 114 (11.7%) were excluded from the study because of incomplete information regarding age, body weight, sex, and neuter status. A control group of 417,079 dogs was selected that included all other dogs with medical conditions unrelated to blastomycosis for which records were submitted to the data base during the same period. The prevalence of blastomycosis in dogs was 205/100,000 admissions during the study period. When veterinary teaching hospitals were grouped on the basis of their general geographic location, dogs in the East South central, East North central, West South central, and South Atlantic regions had a significantly (P < 0.05) increased risk of acquiring blastomycosis, compared with that of dogs in the Mountain/Pacific region. When teaching hospitals from all geographic regions were considered, dogs had a significantly (P < 0.05) increased risk of acquiring blastomycosis in autumn, compared with that in spring. Sporting dogs and hounds, as defined by the American Kennel Club, were at increased risk for blastomycosis. At highest risk were Bluetick Coonhounds, Treeing-walker Coonhounds, Pointers, and Weimaraners, compared with mixed-breed dogs. Ages of dogs with blastomycosis tended to be normally distributed. Generally, the highest-risk group was composed of sexually intact male dogs, 2 to 4 years old, weighing 22.7 to 34.1 kg. This same pattern was observed for sporting dogs and hounds.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis.  相似文献   
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Background

South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species.

Results

Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data.

Conclusions

Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be particularly useful for mapping poorly known, fragmented, or degraded vegetation. We wish to highlight that biome delimitation is not an exact science, and that transparency is needed on how biomes are used as study units in macroevolutionary and ecological research.  相似文献   
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CASE HISTORY: A feral cat captured in the Manawatu region of New Zealand was treated for worms and fleas, and kept confined in a metabolic cage. It showed good appetite and weight gain but had intermittent watery, yellow diarrhoea.

CLINICAL FINDINGS: Clinical examination under sedation was unremarkable and routine blood tests showed no significant abnormalities. The cat was negative for feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Different canned cat foods did not alter the course of the diarrhoea, and the cat was euthanised 6 months after capture. At necropsy, two sections of adult Spirometra tapeworms were found in the jejunum and typical Spirometra eggs were found in colonic contents. Molecular identification of the parasite was undertaken, using the cytochrome- c oxidase subunit-1 gene (cox1) sequence.

DIAGNOSIS: Chronic intermittent diarrhoea associated with Spirometra erinacei / S. erinaceieuropaei infection.

CLINICAL RELEVANCE: Spirometra has not been reported in New Zealand before but has been associated with gastrointestinal disease in cats in other parts of the world. It requires speciestargeted treatment to be eliminated effectively, and is zoonotic. Diagnosis could be diffi cult for clinicians who are not familiar with the parasite and its life cycle.  相似文献   
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The aim of this study was to evaluate the influence that different protocols of urethral catheterization after pharmacological induction (Ur.Ca.P.I.) may have on the semen quality of the domestic cat. The study has been divided into two experiments: one in which different dosages of medetomidine administrated are evaluated and the second one in which the timing of the catheterization after pharmacological induction is tested. In the first experiment, 18 cats were sedated with the recommended dosage of medetomidine (130 μg/kg i.m.) while the other 18 were sedated with a lower dose of the same drug (50 μg/kg i.m.). In the second experiment, three groups were implemented, each containing 25 subjects. In group 1, the semen collection was performed immediately once the pharmacological effect of the drug was reached; in group 2, the semen collection was performed three times every 5 min after the pharmacological effect was reached; finally, in group 3, Ur.Ca.P.I. was performed 20 min after the pharmacological effect was reached. All the different protocols permitted sperm collection, nevertheless the first experiment showed a better quality in terms of volume, concentration, total number of spermatozoa (p < 0.01) and quality of the movement (motility p < 0.05 and forward progressive motility p < 0.01), using a high medetomidine dosage rather than 50 μg/kg i.m. In the second experiment, forward motility was statistically higher (p < 0.01) in the first group and total volume was higher (p < 0.01) in the second and third group, while other parameters were statistically not different. Results suggest that a single catheterization immediately after the onset of the pharmacological effect leads to a good‐quality semen with the lowest possibility of damaging the urethra and that a sedation with 130 μg/kg of medetomidine leads to a better quality sperm collection than 50 μg/kg does.  相似文献   
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