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61.
From January 1999 to April 2002, 14 free-ranging elk were darted with a mixture of Telazol reconstituted with xylazine hydrochloride (HCl) in a forested habitat in southwestern Oklahoma and north-central Arkansas. Elk were darted from ground blinds, tree stands, or a vehicle at distances of 14-46 m and were recovered 37-274 m from the dart site. Elk were located using radiotelemetry with 3-cc disposable Pneu-dart transmitter darts. Mean+/-SD dose of Telazol and xylazine HCl was 590+/-192 mg/ml and 276+/-153 mg/ml, respectively, and mean time to standing after injection of reversal agent was 27 min (range: 1-65 min). The combination of Telazol and xylazine HCl successfully immobilized free-ranging elk, and transmitter-equipped darts permitted successful location of sedated elk by two people in areas of dense forest cover. The dose required to sedate elk appeared to vary depending on physiology and behavior, but no drug-induced mortality occurred despite the wide variance in the doses administered. We recommend 500 mg Telazol reconstituted with 300 mg xylazine HCl as an initial dose for a >or=200 kg elk. If needed to achieve full sedation, up to 3 additional ml of the mixture may be administered without adverse effects.  相似文献   
62.
SpecAlign--processing and alignment of mass spectra datasets   总被引:3,自引:0,他引:3  
SUMMARY: Pre-processing of chromatographic profile or mass spectral data is an important aspect of many types of proteomics and biomarker discovery experiments. Here we present a graphical computational tool, SpecAlign, that enables simultaneous visualization and manipulation of multiple datasets. SpecAlign not only provides all common processing functions, but also uniquely implements an algorithm that enables the complete alignment of each mass spectrum within a loaded dataset. We demonstrate its utility by aligning two datasets each containing six spectra; one set was acquired prior to instrument calibration and the other following calibration. AVAILABILITY: The software is free of charge and available for download from http://ptcl.chem.ox.ac.uk/~jwong/specalign. Supports Windows operating systems including Windows 9X/NT/2000/XP.  相似文献   
63.
BACKGROUND: Biochemical testing for pheochromocytoma by measurement of fractionated plasma metanephrines is limited by false positive rates of up to 18% in people without known genetic predisposition to the disease. The plasma normetanephrine fraction is responsible for most false positives and plasma normetanephrine increases with age. The objective of this study was to determine if we could improve the specificity of fractionated plasma measurements, by statistically adjusting for age. METHODS: An age-adjusted metanephrine score was derived using logistic regression from 343 subjects (including 33 people with pheochromocytoma) who underwent fractionated plasma metanephrine measurements as part of investigations for suspected pheochromocytoma at Mayo Clinic Rochester (derivation set). The performance of the age-adjusted score was validated in a dataset of 158 subjects (including patients 23 with pheochromocytoma) that underwent measurements of fractionated plasma metanephrines at Mayo Clinic the following year (validation dataset). None of the participants in the validation dataset had known genetic predisposition to pheochromocytoma. RESULTS: The sensitivity of the age-adjusted metanephrine score was the same as that of traditional interpretation of fractionated plasma metanephrine measurements, yielding a sensitivity of 100% (23/23, 95% confidence interval [CI] 85.7%, 100%). However, the false positive rate with traditional interpretation of fractionated plasma metanephrine measurements was 16.3% (22/135, 95% CI, 11.0%, 23.4%) and that of the age-adjusted score was significantly lower at 3.0% (4/135, 95% CI, 1.2%, 7.4%) (p < 0.001 using McNemar's test). CONCLUSION: An adjustment for age in the interpretation of results of fractionated plasma metanephrines may significantly decrease false positives when using this test to exclude sporadic pheochromocytoma. Such improvements in false positive rate may result in savings of expenditures related to confirmatory imaging.  相似文献   
64.
Phylogenetic context and Basal metazoan model systems   总被引:5,自引:1,他引:4  
In comparative studies using model organisms, extant taxa areoften referred to as basal. The term suggests that such taxaare descendants of lineages that diverged early in the historyof some larger taxon. By this usage, the basal metazoans comprisejust four phyla (Placozoa, Porifera, Cnidaria, and Ctenophora)and the large clade Bilateria. We advise against this practicebecause basal refers to a region at the base or root of a phylogenetictree. Thus, referring to an extant taxon or species as basal,or as more basal than another, can be misleading. While muchprogress has been made toward understanding some of the phylogeneticrelationships within these groups, the relationships among themare still largely not known with certainty. Thus, sound inferencesfrom comparative studies of model organisms demand continuedillumination of phylogeny. Hypotheses about the mechanisms underlyingmetazoan evolution can be drawn from the study of model organismsin Cnidaria, Ctenophora, Placozoa, and Porifera, but it is clearthat these model organisms are likely to be derived in manyrespects. Therefore, testing these hypotheses requires the studyof yet additional model organisms. The most effective testsare those that investigate model organisms with phylogeneticpositions among two sister groups comprising a larger cladeof interest.  相似文献   
65.
66.
Cancer cells are capable of serum- and anchorage-independent growth, and focus formation on monolayers of normal cells. Previously, we showed that RACK1 inhibits c-Src kinase activity and NIH3T3 cell growth. Here, we show that RACK1 partially inhibits v-Src kinase activity, and the serum- and anchorage-independent growth of v-Src transformed cells, but has no effect on focus formation. RACK1-overexpressing v-Src cells show disassembly of podosomes, which are actin-rich structures that are distinctive to fully transformed cells. Together, our results demonstrate that RACK1 overexpression in v-Src cells partially reverses the transformed phenotype of the cells. Our results identify an endogenous inhibitor of the oncogenic Src tyrosine kinase and of cell transformation.  相似文献   
67.
We investigated the formation and pharmacology of prostaglandin E(3) (PGE(3)) derived from fish oil eicosapentaenoic acid (EPA) in human lung cancer A549 cells. Exposure of A549 cells to EPA resulted in the rapid formation and export of PGE(3.) The extracellular ratio of PGE(3) to PGE(2) increased from 0.08 in control cells to 0.8 in cells exposed to EPA within 48 h. Incubation of EPA with cloned ovine or human recombinant cyclooxygenase 2 (COX-2) resulted in 13- and 18-fold greater formation of PGE(3), respectively, than that produced by COX-1. Exposure of A549 cells to 1 microM PGE(3) inhibited cell proliferation by 37.1% (P < 0.05). Exposure of normal human bronchial epithelial (NHBE) cells to PGE(3), however, had no effect. When A549 cells were exposed to EPA (25 microM) or a combination of EPA and celecoxib (a selective COX-2 inhibitor), the inhibitory effect of EPA on the growth of A549 cells was reversed by the presence of celecoxib (at both 5 and 10 microM). This effect appears to be associated with a 50% reduction of PGE(3) formation in cells treated with a combination of EPA and celecoxib compared with cells exposed to EPA alone. These data indicate that exposure of lung cancer cells to EPA results in a decrease in the COX-2-mediated formation of PGE(2), an increase in the level of PGE(3), and PGE(3)-mediated inhibition of tumor cell proliferation.  相似文献   
68.
We report the development of 11 polymorphic microsatellite loci in pacific white shrimp (Litopenaeus vannamei) using an unenriched genomic library. The number of the alleles ranged from two to 18 and observed hererozygosity ranged from 0.0286 to 0.9429, indicating that these markers will be useful for population studies and mapping in pacific white shrimp. Seven loci were detected deviated from Hardy–Weinberg, caused by deficiency of heterozygote, suggesting population genetic structure across the sampled population. No evidence for linkage disequilibrium was found.  相似文献   
69.
70.
Scientists predict that global agricultural lands will expand over the next few decades due to increasing demands for food production and an exponential increase in crop‐based biofuel production. These changes in land use will greatly impact biogeochemical and biogeophysical cycles across the globe. It is therefore important to develop models that can accurately simulate the interactions between the atmosphere and important crops. In this study, we develop and validate a new process‐based sugarcane model (included as a module within the Agro‐IBIS dynamic agro‐ecosystem model) which can be applied at multiple spatial scales. At site level, the model systematically under/overestimated the daily sensible/latent heat flux (by ?10.5% and 14.8%, H and λE, respectively) when compared against the micrometeorological observations from southeast Brazil. The model underestimated ET (relative bias between ?10.1% and –12.5%) when compared against an agro‐meteorological field experiment from northeast Australia. At the regional level, the model accurately simulated average yield for the four largest mesoregions (clusters of municipalities) in the state of São Paulo, Brazil, over a period of 16 years, with a yield relative bias of ?0.68% to 1.08%. Finally, the simulated annual average sugarcane yield over 31 years for the state of Louisiana (US) had a low relative bias (?2.67%), but exhibited a lower interannual variability than the observed yields.  相似文献   
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