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61.
The interaction between tectonism and erosion produces rugged landscapes in actively deforming regions. In the northwestern Himalaya, the form of the landscape was found to be largely independent of exhumation rates, but regional trends in mean and modal elevations, hypsometry (frequency distribution of altitude), and slope distributions were correlated with the extent of glaciation. These observations imply that in mountain belts that intersect the snowline, glacial and periglacial processes place an upper limit on altitude, relief, and the development of topography irrespective of the rate of tectonic processes operating. 相似文献
62.
Long‐term Effects of Pyrethrin and Cyfluthrin,a Type II Synthetic Pyrethroid,Insecticide Applications on Bull Reproductive Parameters 下载免费PDF全文
JL Stewart CF Shipley FA Ireland VL Jarrell CL Timlin DW Shike TL Felix 《Reproduction in domestic animals》2016,51(5):680-687
The objectives of this study were to determine effects of cyfluthrin and pyrethrin spray products, used in combination with cyfluthrin topical and ear tag applications, on bull reproductive parameters over 18 weeks. Angus or Angus x Simmental bulls were randomly assigned to one of three treatment groups: (i) no exposure to pyrethrins/cyfluthrin (CONT; n = 10), (ii) cyfluthrin ear tag and topical applications (ET; n = 10), or (iii) cyfluthrin ear tag, topical, premise spray and pyrethrin fog spray applications (ET+S; n = 8). Bull body weight was measured every 3 week, and body condition score and scrotal circumference were recorded on weeks 0, 9 and 18. Semen and serum were collected every 3 weeks for sperm evaluation and testosterone measurement, respectively. There was a treatment × week interaction (p < 0.01) for sperm with primary defects; bulls in CONT group had a greater (p = 0.01) percentage of sperm with primary defects than bulls treated with insecticides at week 18. Overall and progressive sperm motility, normal sperm morphology, secondary sperm defects and serum testosterone concentrations changed (p < 0.01) over time in all bulls; however, treatment did not affect (p ≥ 0.13) any of these parameters. There were also no treatment effects (p ≥ 0.08) on bull body weight, body condition score or scrotal circumference. The use of pyrethrin‐ and cyfluthrin‐based insecticides, regardless of application, did not negatively affect reproductive parameters in beef bulls when administered over 18 weeks. 相似文献
63.
Hinchcliff KW Rush BR Farris JW 《Journal of the American Veterinary Medical Association》2005,227(2):276-280
OBJECTIVE: To evaluate plasma epinephrine and norepinephrine concentrations and serum cortisol concentration in horses with colic and assess the relationship of these variables with clinical signs, routinely measured clinicopathologic variables, and outcome in affected horses. DESIGN: Prospective observational study. ANIMALS: 35 horses with colic. PROCEDURE: Blood samples were collected within 30 minutes of arrival at the veterinary hospital from horses referred because of colic. Plasma and serum samples were analyzed for cortisol, epinephrine, norepinephrine, lactate, and electrolyte concentrations and acid-base variables. Heart rate at admission and outcome (survival or nonsurvival) were recorded. Univariate logistic regression was used to calculate crude (unadjusted) odds ratios and 95% confidence intervals. RESULTS: Of the 35 horses with colic, 26 survived. Higher plasma epinephrine, plasma lactate, and serum cortisol concentrations were significantly associated with increased risk of nonsurvival, but plasma norepinephrine concentration was not associated with outcome. Plasma epinephrine concentration was significantly correlated with heart rate (r = 0.68), plasma lactate concentration (r = 0.87), blood pH (r = -0.83), anion gap (r = 0.74), and base excess (r = -0.81). CONCLUSIONS AND CLINICAL RELEVANCE: The risk of death appears to be greater in colic-affected horses with high circulating concentrations of epinephrine and cortisol. The correlation of epinephrine with other biochemical markers of illness severity and with heart rate indicates that the degree of sympathetic activation in horses with colic can be inferred from routinely measured variables. 相似文献
64.
Freeman LM Rush JE Farabaugh AE Must A 《Journal of the American Veterinary Medical Association》2005,226(11):1864-1868
OBJECTIVE: To develop and evaluate a questionnaire (functional evaluation of cardiac health [FETCH] questionnaire) for assessing health-related quality of life in dogs with cardiac disease. DESIGN: Prospective study. ANIMALS: 360 dogs with cardiac disease PROCEDURE: The questionnaire was developed on the basis of widely accepted clinical signs of cardiac disease in dogs. A FETCH score was calculated by summing responses to questionnaire items; possible scores ranged from 0 to 85. For questionnaire validation, owners of 60 dogs were asked to complete the questionnaire and provide an overall assessment of their dogs' quality of life (16 owners completed the questionnaire twice). Disease severity was assessed with the International Small Animal Cardiac Health Council (ISACHC) classification for cardiac disease. Following validation, the final questionnaire was administered to owners of the remaining 300 dogs. RESULTS: Internal consistency of the questionnaire was good, and the FETCH score was significantly correlated with the owner-reported quality-of-life score and with ISACHC classification. For owners that completed the questionnaire twice, scores were significantly correlated. During the second phase of the study, the FETCH score ranged from 0 to 70 (median, 7) and was significantly correlated with ISACHC classification, but did not vary significantly with underlying disease. For dogs examined twice, the change in FETCH score was significantly greater for dogs in which ISACHC classification improved than for dogs in which ISACHC classification was unchanged. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the FETCH questionnaire is a valid and reliable method for assessing health-related quality of life in dogs with cardiac disease. 相似文献
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Smith CE Rozanski EA Freeman LM Brown DJ Goodman JS Rush JE 《Journal of the American Veterinary Medical Association》2004,225(8):1237-1241
OBJECTIVE: To determine duration of administration, complications, and frequency of aortic thromboembolism associated with administration of low molecular weight heparin (dalteparin) in cats. DESIGN: Retrospective study. ANIMALS: 57 cats treated with dalteparin PROCEDURE: Data were recorded from the medical records of cats treated with dalteparin, and owners were contacted by telephone for information regarding ease of administration and possible adverse effects. RESULTS: Dalteparin was easily administered by owners. Median dose was 99 U/kg (45 U/lb) once or twice daily. Bleeding complications were infrequent. Of 43 cats with cardiomyopathy that received owner-administered dalteparin for a median follow-up time of 172 days, 8 cats developed documented or possible arterial thromboembolism. CONCLUSIONS AND CLINICAL RELEVANCE: Dalteparin was easily administered by owners and was well tolerated by cats. Whether dalteparin administration can reduce the frequency or severity of arterial thromboembolism is not yet known. 相似文献
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69.
Remote detection of rhizomania in sugar beets 总被引:4,自引:0,他引:4
ABSTRACT As a prelude to remote sensing of rhizomania, hyper-spectral leaf reflectance and multi-spectral canopy reflectance were used to study the physiological differences between healthy sugar beets and beets infested with Beet necrotic yellow vein virus. This study was conducted over time in the presence of declining nitrogen levels. Total leaf nitrogen was significantly lower in symptomatic beets than in healthy beets. Chlorophyll and carotenoid levels were reduced in symptomatic beets. Vegetative indices calculated from leaf spectra showed reductions in chlorophyll and carotenoids in symptomatic beets. Betacyanin levels estimated from leaf spectra were decreased at the end of the 2000 season and not in 2001. The ratio of betacyanins to chlorophyll, estimated from canopy spectra, was increased in symptomatic beets at four of seven sampling dates. Differences in betacyanin and carotenoid levels appeared to be related to disease and not nitrogen content. Vegetative indices calculated from multi-spectral canopy spectra supported results from leaf spectra. Logistic regression models that incorporate vegetative indices and reflectance correctly predicted 88.8% of the observations from leaf spectra and 87.9% of the observations for canopy reflectance into healthy or symptomatic classes. Classification was best in August with a gradual decrease in accuracy until harvest. These results indicate that remote sensing technologies can facilitate detection of rhizomania. 相似文献
70.
White HL Rozanski EA Tidwell AS Chan DL Rush JE 《Journal of the American Veterinary Medical Association》2003,222(11):1573-5, 1547
Two adult domestic shorthair cats were examined because of pneumothorax. Neither had a history of trauma, and spontaneous pneumothorax secondary to small airway disease was diagnosed. In both cats, treatment consisted of thoracocentesis for evacuation of air and administration of anti-inflammatory agents. One cat had multiple episodes of pneumothorax and eventually died; the other had only a single episode of pneumothorax. Small airway disease should be considered as a potential underlying cause in cats that develop spontaneous pneumothorax. Additionally, the potential for pneumothorax should be considered in cats with small airway disease, particularly when clinical signs suddenly become much worse. 相似文献