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排序方式: 共有1348条查询结果,搜索用时 15 毫秒
31.
32.
Medical records from 111 threatened bald eagles (86%, Haliaeetus leucocephalus) and peregrine falcons (14%, Falco peregrinus) admitted to the Wildlife Center of Virginia from 1993 to 2003 were reviewed to identify submitters, causes of morbidity and mortality, and final disposition. Half of all patients admitted were submitted by the Virginia Department of Game and Inland Fisheries personnel. Trauma was the most common reason for presentation in bald eagles (70%) and peregrine falcons (81%). Additional causes of morbidity and mortality in bald eagles included toxicoses (10%), infectious diseases (8%), and orphaned young (1%). Neoplasia was confirmed in two trauma cases, suggesting underlying disease might have increased susceptibility to acute traumatic injuries. Peregrine falcons were also admitted for infectious disease (19%). The most frequent infectious disease for both species was West Nile virus. Thirty-nine percent of patients were released back into the wild, 28% were euthanized, 20% died, and 13% were placed in captivity. Postrelease monitoring that would determine whether rehabilitated animals survived to contribute to threatened populations was not performed in this study. 相似文献
33.
Amanda B McLaughlin Jonathan H Epstein Vibhu Prakash Craig S Smith Peter Daszak Hume E Field Andrew A Cunningham 《Journal of zoo and wildlife medicine》2007,38(3):446-452
Although bats of the genus Pteropus are important ecologically as pollinators and natural hosts for zoonotic pathogens, little is known about their basic physiology. Hematology and plasma biochemistries were determined from wild-caught flying foxes (Pteropus giganteus) in northern India (n=41). Mean lymphocyte differential count was higher for juveniles than adults. Mean platelet count was lower than previously reported. No hemoparasites were observed. No differences were observed between plasma biochemistry values of male and female bats, juveniles and adults, or lactating and nonlactating females. Variation in aspartate aminotransferase (AST) was seen based on body condition score. Blood urea nitrogen and cholesterol concentrations were lower in P. giganteus than other mammalian groups, but were consistent with those reported from other Pteropus species. Alanine aminotransferase and AST concentrations were higher than those reported for Pteropus vampyrus, a closely related species. This study provides basic physiologic information that can be used in future health and disease studies of Indian flying foxes. 相似文献
34.
Sarah L. Rawlings Richard J. OConnell Jonathan R. Green 《Physiological and Molecular Plant Pathology》2007,70(4-6):110-119
The spores (conidia) of the bean anthracnose fungal pathogen, Colletotrichum lindemuthianum, adhere to the aerial parts of plants to initiate the infection process. In previous studies we have shown that the Colletotrichum spores are surrounded by a fibrillar spore coat, comprising several major glycoproteins. Previous evidence showed that a monoclonal antibody (UB20) that recognised these glycoproteins was able to inhibit adhesion of spores to a hydrophobic surface. In this paper we have further studied the role of the spore coat in adhesion, germination and fungal development by studying the effects of UB20 and protease treatment of spores. The latter treatment has previously been shown to remove the spore coat. Spores germinate on glass, polystyrene and water agar, however, appressoria only develop on glass or polystyrene, showing a requirement for a hard surface. Removal of the spore coat with protease inhibits adhesion at 30 min, before the secretion of ECM glycoproteins. Protease treatment also inhibits the development of appressoria and reduces pathogenicity on leaves. Incubation of spores with the MAb UB20 inhibits adhesion at 30 min, but does not affect appressorium formation or pathogenicity. The results suggest that an intact spore coat has two functions; it is required for adhesion to a hydrophobic surface and for the detection of a hard surface necessary for appressorium formation. We suggest that contact with a hard surface, rather than adhesion, is the key event leading to appressorium formation. 相似文献
35.
Jonathan E. Hare Laurent Viel 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(3):163-170
Horses are known to acquire small airway disease (SAD), an allergen-induced naturally occurring syndrome of reversible obstructive lung disease accompanied by airway hyperresponsiveness and increased inflammatory cell numbers on bronchoalveolar lavage (BAL). This disorder has received scant attention in young racehorses. The purpose of the present report was to examine the effect of BAL eosinophilia in young racehorses on clinical examination, BAL, hematology, airway responsiveness, and on pulmonary function at rest and after a standardized exercise challenge. Five (3 males, 2 females; age 2.6 ± 0.9 years) with a history of respiratory compromise and BAL eosinophil differential count <5% and 6 controls (4 males, 2 females; age 3.5 ± 1.0 years) training and performing to expectation with normal BAL cell differential (eosinophils < 1%) were studied. Respiratory system clinical examination was performed and expressed as a clinical score. Arterial blood gas measurements, CBC, and pulmonary function testing were performed at rest. Pulmonary mechanics measurements were repeated 1 hour and 20 hours after a standardized treadmill exercise challenge. Incremental histamine inhalation challenge was performed and the concentration of histamine effecting a 35% decrease in dynamic compliance (PC35CDyn ) was determined. Significant differences were noted between and controls with regard to clinical score ( P = .01), blood eosinophils ( P = .04), BAL cell count ( P = .04), BAL macrophage differential ( P = .04), PC35CDyn ( P = .008), and tidal volume and respiratory rate at 20 hours following exercise challenge ( P = .05). We conclude that pulmonary eosinophilia and airway hyperresponsiveness are manifest in some young horses without overt airway obstruction at rest. We speculate that these may be early events in the natural progression of heaves. 相似文献
36.
37.
A 36 year (1951–1986) record of water temperatures in Mississippi catfish ponds is synthesized from relationships with existing air temperature records. Multiple regression analysis is used to produce the following predictor equations for morning and afternoon pond temperatures: morning pond temperatures = 2.218 + 0.062(max air temp, day before) + 0.285(min air temp, same day) + 0.561 (afternoon pond temp, day before) (1) afternoon pond temperatures
= 2.071 - 0.068(min air temp, same day) + 0.651 (morning pond temp, same day) + 0.373(max air temp, same day) (2)
The derived pond temperature record is analyzed to produce annual average regimes; daily average, maximum, and minimum temperatures with standard deviations; and probabilities at 10 levels of Occurrence through the year and for each individual month. Applications for the aquaculture industry are presented and evaluated. 相似文献
= 2.071 - 0.068(min air temp, same day) + 0.651 (morning pond temp, same day) + 0.373(max air temp, same day) (2)
The derived pond temperature record is analyzed to produce annual average regimes; daily average, maximum, and minimum temperatures with standard deviations; and probabilities at 10 levels of Occurrence through the year and for each individual month. Applications for the aquaculture industry are presented and evaluated. 相似文献
38.
39.
Barbara Moser Christoph Bachofen Jonathan D. Müller Marek Metslaid Thomas Wohlgemuth 《Annals of Forest Science》2016,73(4):959-970
Key message
Pinus sylvestris seedlings quickly expand their roots to deeper soil layers while Pseudotsuga menziesii concentrates its root system in the topsoil, thereby running the risk of desiccation during long dry spells, as indicated by lower survival after simulated summer drought.Context
Pseudotsuga menziesii (Douglas-fir) is regarded as a promising species to maintain the productivity of Central European lowland forests given the projected increase of long dry spells.Aims
Will the species be able to regenerate from seed and spread outside plantations in a drier temperate Europe?Methods
We measured the relative growth rate, biomass allocation, root architecture, and phenotypic plasticity of Pseudotsuga menziesii seedlings sown in a common garden and grown under current precipitation and prolonged drought, respectively. The species’ competitive ability with respect to Pinus sylvestris L., the most drought-tolerant native conifer in Central Europe, was assessed during three growing seasons.Results
Pinus sylvestris seedlings had higher relative growth rates than did Pseudotsuga menziesii seedlings, first in terms of aboveground biomass and later in terms of shoot height. This resulted in heavier and taller seedlings after three growing seasons under both moist and dry conditions. Shorter vertical roots corresponded with lower survival of Pseudotsuga menziesii seedlings under dry conditions.Conclusion
Fast root proliferation allows Pinus sylvestris seedlings to reach deeper water pools that are less rapidly depleted during transient drought. By contrast, the shallow root system might put Pseudotsuga menziesii seedlings at the risk of desiccation during prolonged dry spells.40.
ASSOCIATIONS BETWEEN ULTRASOUND AND CLINICAL FINDINGS IN 87 CATS WITH URETHRAL OBSTRUCTION
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Urethral obstruction is a life‐threatening form of feline lower urinary tract disease. Ultrasonographic risk factors for reobstruction have not been previously reported. Purposes of this retrospective cross‐sectional study were to describe urinary tract ultrasound findings in cats following acute urethral obstruction and determine whether ultrasound findings were associated with reobstruction. Inclusion criteria were a physical examination and history consistent with urethral obstruction, an abdominal ultrasound including a full evaluation of the urinary system within 24 h of hospitalization, and no cystocentesis prior to ultrasound examination. Medical records for included cats were reviewed and presence of azotemia, hyperkalemia, positive urine culture, and duration of hospitalization were recorded. For medically treated cats with available outcome data, presence of reobstruction was also recorded. Ultrasound images were reviewed and urinary tract characteristics were recorded. A total of 87 cats met inclusion criteria. Common ultrasound findings for the bladder included echogenic urine sediment, bladder wall thickening, pericystic effusion, hyperechoic pericystic fat, and increased urinary echoes; and for the kidneys/ureters included pyelectasia, renomegaly, perirenal effusion, hyperechoic perirenal fat, and ureteral dilation. Six‐month postdischarge outcomes were available for 61 medically treated cats and 21 of these cats had reobstruction. No findings were associated with an increased risk of reobstruction. Ultrasonographic perirenal effusion was associated with severe hyperkalemia (P = 0.009, relative risk 5.75, 95% confidence interval [1.54–21.51]). Findings supported the use of ultrasound as an adjunct for treatment planning in cats presented with urethral obstruction but not as a method for predicting risk of reobstruction. 相似文献