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121.
Rickettsia species antibodies have been detected in some cats but it is unknown whether infected cats develop clinical signs. The prevalence of Rickettsia species deoxyribonucleic acid (DNA) in blood from clinically ill cats has not been determined. The objective of this study was to determine if cats with fever (body temperature >or=102.5 degrees F [39.2 degrees C]) were more likely to have evidence of rickettsial infection than healthy, age-matched, control cats with a body temperature<102.5 degrees F. Rickettsia species polymerase chain reaction (PCR) assays were performed to detect rickettsial DNA extracted from blood (71 paired samples), indirect immunofluorescence assays (IFA) were performed to detect serum antibodies against Rickettsia felis (90 paired samples) and Rickettsia rickettsii (91 paired samples), and the results between pairs were compared. All samples were negative for Rickettsia species DNA. More cats with fever were seropositive for R felis or R rickettsii than control cats, but results were not statistically significant. Results of this pilot study failed to show an association between Rickettsia species DNA or Rickettsia species antibodies and fever.  相似文献   
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To evaluate the isotopic composition of the solar nebula from which the planets formed, the relation between isotopes measured in the solar wind and on the Sun's surface needs to be known. The Genesis Discovery mission returned independent samples of three types of solar wind produced by different solar processes that provide a check on possible isotopic variations, or fractionation, between the solar-wind and solar-surface material. At a high level of precision, we observed no significant inter-regime differences in 20Ne/22Ne or 36Ar/38Ar values. For 20Ne/22Ne, the difference between low- and high-speed wind components is 0.24 +/- 0.37%; for 36Ar/38Ar, it is 0.11 +/- 0.26%. Our measured 36Ar/38Ar ratio in the solar wind of 5.501 +/- 0.005 is 3.42 +/- 0.09% higher than that of the terrestrial atmosphere, which may reflect atmospheric losses early in Earth's history.  相似文献   
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In this retrospective study, we describe 14 cats diagnosed with hepatic abscesses. The objective of the study was to report the clinical signs, physical examination findings, clinicopathologic findings, and outcomes in affected cats. These findings were then compared with those previously reported in dogs and humans. Clinical signs were vague and included anorexia, lethargy, and weight loss. Only 23% of cats had fever, whereas 31% were hypothermic. Increases in serum activities of alanine aminotransferase and alkaline phosphatase were found in 45 and 18%, respectively, of the 11 cats that had laboratory work performed. Abdominal ultrasound examinations were performed in 7 cats, and abnormalities were found in 71% of them. Four cats had solitary abscesses, all of which were located in the right liver lobes. The other 10 cats had multifocal small abscesses or microabscesses, and all of these cats had clinical signs suggestive of sepsis. Cytologic evaluation of samples obtained by abdominocentesis indicated septic inflammation in 67% of cats in which peritoneal fluid was analyzed. Hepatic abscess cultures yielded polymicrobial growth in 66% of the cats: Escherichia coli was the most commonly cultured organism. Overall mortality rate was 79%. All survivors underwent exploratory laparotomy for partial hepatectomy to resect the abscess followed by medical management. Hepatic abscesses should be considered in cats with signs consistent with sepsis. More routine use of ultrasonography may aid in earlier diagnosis of hepatic abscesses, potentially improving prognosis and outcome.  相似文献   
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Earthworms are recognized to play an important role in the decomposition of organic materials. To test the use of earthworms as an indicator of plant litter decomposition, we examined the abundance and biomass of earthworms in relation to plant litter decomposition in a tropical wet forest of Puerto Rico. We collected earthworms at 0–0.1 m and 0.1–0.25 m soil depths from upland and riparian sites that represent the natural variation in soils and decomposition rates within the forest. Earthworms were hand-sorted and weighed for both fresh and dry biomass. Earthworms were dominated by the exotic endogeic species Pontoscolex corethrurus Müller; they were more abundant, and had higher biomasses in the upland than in riparian sites of the forest. Plant leaf litter decomposed faster in the upland than riparian sites. We found that earthworm abundance in the upper 0.1 m of the soil profile positively correlated with decomposition rate of plant leaf litter. Ground litter removal had no effect on the abundance or biomass of endogeic earthworms. Our data suggest that earthworms can be used to predict decomposition rates of plant litter in the tropical wet forest, and that the decomposition of aboveground plant litter has little influence on the abundance and biomass of endogeic earthworms.  相似文献   
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