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排序方式: 共有194条查询结果,搜索用时 125 毫秒
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Bibring JP Langevin Y Mustard JF Poulet F Arvidson R Gendrin A Gondet B Mangold N Pinet P Forget F Berthé M Bibring JP Gendrin A Gomez C Gondet B Jouglet D Poulet F Soufflot A Vincendon M Combes M Drossart P Encrenaz T Fouchet T Merchiorri R Belluci G Altieri F Formisano V Capaccioni F Cerroni P Coradini A Fonti S Korablev O Kottsov V Ignatiev N Moroz V Titov D Zasova L Loiseau D Mangold N Pinet P Douté S Schmitt B Sotin C Hauber E Hoffmann H Jaumann R Keller U Arvidson R Mustard JF Duxbury T 《Science (New York, N.Y.)》2006,312(5772):400-404
Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the "phyllocian" era) are found in the oldest terrains; sulfates were formed in a second era (the "theiikian" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the "siderikian") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet. 相似文献
23.
OBJECTIVE: To determine whether the literature filtering process, a vital initial component of a systematic literature review, could be successfully completed by nutrition professionals or non-professionals. DESIGN: Using a diet-disease relationship as the guideline topic, inter-rater agreement for the title and abstract filtering processes between and among professionals and non-professionals was assessed and compared with an expert reference standard. Predetermined eligibility criteria were applied by all raters to 185 titles and 90 abstracts. Filtering decisions were initially made independently and then revised after a within-pair consensus meeting. SUBJECTS: The raters were six dietitians (RD) and six nutrition graduate students (Grad). To assess inter-rater agreement (reliability), each group was divided into three pairs. RESULTS: Weighted and unweighted kappa statistics and percentage agreement were calculated to determine the inter-rater agreement within pairs. Sensitivity and specificity estimates were determined by comparing responses with those of an expert reference standard. Overall, Grad pairs demonstrated greater inter-rater agreement than RD pairs for title filtering (P<0.05); no differences were observed for abstract filtering. Compared with the expert reference standard, every rater and pair had false-negative responses for both title and abstract filtering. CONCLUSIONS: After consensus meetings, both RDs and Grads were comparable in their agreement on title and abstract filtering, although important differences remained compared with the expert reference standard. This study provides preliminary findings on the value of utilising a non-expert pair in developing guidelines, and suggests that the literature filtering process is complex and quite subjective. 相似文献
24.
Queiroz-Castro P Egger C Redua MA Rohrbach BW Cox S Doherty T 《American journal of veterinary research》2006,67(12):1962-1966
OBJECTIVE: To evaluate the effects of ketamine, magnesium sulfate, and their combination on the minimum alveolar concentration (MAC) of isoflurane (ISO-MAC) in goats. ANIMALS: 8 adult goats. PROCEDURES: Anesthesia was induced with isoflurane delivered via face mask. Goats were intubated and ventilated to maintain normocapnia. After an appropriate equilibration period, baseline MAC (MAC(B)) was determined and the following 4 treatments were administered IV: saline (0.9% NaCl) solution (loading dose [LD], 30 mL/20 min; constant rate infusion [CRI], 60 mL/h), magnesium sulfate (LD, 50 mg/kg; CRI, 10 mg/kg/h), ketamine (LD, 1 mg/kg; CRI, 25 microg/kg/min), and magnesium sulfate (LD, 50 mg/kg; CRI, 10 mg/kg/h) combined with ketamine (LD, 1 mg/kg; CRI, 25 microg/kg/min); then MAC was redetermined. RESULTS: Ketamine significantly decreased ISOMAC by 28.7 +/- 3.7%, and ketamine combined with magnesium sulfate significantly decreased ISOMAC by 21.1 +/- 4.1%. Saline solution or magnesium sulfate alone did not significantly change ISOMAC. CONCLUSIONS AND CLINICAL RELEVANCE: Ketamine and ketamine combined with magnesium sulfate, at doses used in the study, decreased the end-tidal isoflurane concentration needed to maintain anesthesia, verifying the clinical impression that ketamine decreases the end-tidal isoflurane concentration needed to maintain surgical anesthesia. Magnesium, at doses used in the study, did not decrease ISOMAC or augment ketamine's effects on ISOMAC. 相似文献
25.
Ullmann LS Hoffmann JL de Moraes W Cubas ZS dos Santos LC da Silva RC Moreira N Guimaraes AM Camossi LG Langoni H Biondo AW 《Journal of zoo and wildlife medicine》2012,43(2):223-228
Leptospirosis is a bacterial zoonosis of worldwide distribution and is endemic in tropical countries, where rodents and other wild mammals are abundant and may act as reservoirs. Leptospirosis has become a concern in captive wild animals, due mostly to their exposure to contaminated urine or environment. Although domestic cats (Felis catus) have been reported refractory to leptospirosis, serology and disease in captive wild felids is still unclear. In this study 57 adult, clinically healthy felids, including 1 Geoffroy's cat (Leopardus geoffroyi), 3 jaguarundis (Puma yagouaroundi), 17 margays (Leopardus wiedii), 22 little spotted cats (Leopardus tigrinus), and 14 ocelots (Leopardus pardalis) kept in captivity at the Sanctuary at the Itaipu Binacional hydroelectric power plant (Bela Vista Biological Sanctuary), Foz do Iguacu City, Paraná State, Brazil, were serologically surveyed for the presence of antibodies against 28 serovars of Leptospira spp. by microagglutination test (MAT). Two animals (3.5%) were seropositive: one male ocelot to the serovar Cynopteri (titer 100) and one female margay to Autumnalis (100) and Butembo (200). The captive-born, 5-yr-old ocelot had been solitary housed in an individual cage. The approximately 21-yr-old wild-caught margay was also kept individually. None of the tested animals showed signs ofleptospirosis. During a study conducted 4 yr previously in the same facility, this particular margay also tested positive for the same two serovars, among others. The present study indicates that the felids tested for Leptospira spp. by MAT were exposed to serovars, but did not demonstrate clinical signs of disease. Comparison with a previous study suggests that serovar titers may vary over time and that leptospirosis dynamics remains unclear in wild felids. 相似文献
26.
DVMK. Marcia Murphy 《Clinical Techniques in Small Animal Practice》2001,16(4):236-241
Otitis externa, inflammation of the externa ear canal, is relatively easy to diagnose based on the history and physical examination findings. The diagnosis of otitis media, inflammation of the middle ear cavity, is more challenging, with the work-up being both costly and, at times, invasive. The pathogenesis of otitis externa has been classified into predisposing, primary, and perpetuating factors. It is critical to the management of ear disease that the clinician recognize and investigate which factors are contributing to each individual patient's ear disease. Failure to identify and address the primary and/or predisposing factors is the most common cause of chronic recurrent otitis externa. Chronic inflammation of the ear canal leads to the development of the perpetuating factors, which may be the major reason for treatment failure, regardless of the primary cause of the ear disease. In this article, the predisposing, primary, and perpetuating factors involved in ear disease will be presented, along with a review of the techniques used in the diagnosis of otitis externa and otitis media. 相似文献
27.
Hematological and coagulation profiles were studied in crossbred dogs experimentally infected with Angiostrongylus vasorum. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L(3)) of A. vasorum per kilogram of body weight. A third group of five uninfected animals was used as control. One sample of 10 ml of blood was collected from each animal on the 10, 20, 30, and 45 days after inoculation (dai) and at 30-day intervals thereafter for the remainder of the 210-day experimental period. The blood sample was used for the complete hemogram and platelet count, as well as measurements of prothrombin time, partial thromboplastin time and factors V and VIII. Anemia was observed in infected dogs, 6 weeks after the infection. The eosinophils presented peaks in four periods after infection. Thrombocytopenia became accentuated on the 72 dai. Decreased prothrombin time activity and increased partial thromboplastin time were observed at the 6 and 9 weeks after infection and decreased of factors VIII and V activities occurred from 4 to 6 weeks after infection. It may be conclude that infection by A. vasorum in dogs may cause a discrete anemia during the acute phase which is probably regenerative. In addition, important hemostatic alterations due to the infection suggest a chronic intravascular consumption coagulopathy. 相似文献
28.
Shannon C. Thorum Sarah S. Comstock Shelly N. Hester Jill M. Shunk Marcia H. Monaco Sharon M. Donovan 《Veterinary immunology and immunopathology》2013,151(1-2):63-72
Bronchial-associated immune development is critically important to protect neonates from respiratory infections. Herein, bronchial-associated immune development in formula-fed and sow-reared pigs is described. Colostrum-fed newborn piglets were fed medicated sow milk replacer formula beginning at 48 h of life or remained with the sow. Blood and tissues were sampled at one-week (d7) and three-weeks (d21) of age. Lymphocyte subpopulations, including T helper 2, cytotoxic T, memory T, and NK cells, in peripheral blood, mediastinal lymph nodes, and thoracic lymph nodes were identified using flow cytometry. Additionally, IL-1β, IL-6, IL-12, TNFα, TGF-β1, TGF-β2, IFNα, IFNβ, and dectin gene expression were analyzed by quantitative RT-PCR. Total IgG, IgM, and IgA concentrations in serum were analyzed. Dietary and developmental effects were observed. This set of baseline measurements provides a framework for future respiratory challenge studies where the effects of diet on the neonate's ability to resist and/or recover from infection can be tested. 相似文献
29.
This meta‐analysis based on 19 studies from Finland comprising 43 grass silages was undertaken to evaluate the effect of silage quality on liquid yield, liquid composition and retained compounds in liquid using four different liquid–solid separation methods. Silages were classified according to species (grass, clover or a mixture of them), additive treatment (no, biological or formic acid‐based additive) and harvest (primary growth or regrowth). A mixed model regression analysis with random study effect was used to evaluate the impact of silage characteristics on biorefinery efficiency. There was a large variation in silage quality in the data set. Silage dry‐matter concentration was the characteristic most highly correlated with liquid yield for all separation methods, and when used as an independent variable in the model, it resulted in the best predictions. The liquid–solid separation methods presented a great variation in the liquid yield, ranging from 0.26 to 0.56 when silage dry‐matter concentration was standardized to 250 g/kg. There was no effect of additive treatment and harvest in the estimation of the biorefinery potential, but species was a significant variable in predicting liquid yield for the laboratory‐scale presses with higher liquid yield for mixed grass and legume. The high correlation between silage quality and liquid yield and liquid composition provides potential to predict the biorefinery potential based on equations developed for each separation method. This information can be used to modify the silage production systems so that they best meet the requirements of a green biorefinery process. 相似文献
30.
Multivariate approach to the measurement of tomato maturity and gustatory attributes and their rapid assessment by Vis-NIR spectroscopy 总被引:1,自引:0,他引:1
Standard methods for determining quality and maturity are time- and labor-consuming and generally measure individual criteria at a specific time, without considering relationships among quality parameters. To propose a rapid and nondestructive analysis method describing multidimensional quality variables, an experiment was undertaken with mature green to overripe tomato fruits found on the North American retail markets. Factor analysis was used to analyze results. Four factors were considered, representing 81% of total variance. The first one, tomato maturity stage (TMS), is related to color, lycopene content, firmness, titratable acidity (TA), pH, and soluble solids (SS). Nondestructive rapid assessment by vis-NIR spectroscopy can predict TMS (r(2)=0.93). Factors 2 and 3 are both related to taste and should be considered simultaneously. Factor 2, called the gustatory index, is linked to electrical conductivity (EC), SS, TA, and pH. Factor 3, defined by SS, can be directly measured by a refractometer. Four categories of taste are proposed; the most desirable one ranks high both in soluble solids (above 4.5 degrees Brix) and in gustatory index (above 0). It was not possible to measure the gustatory index by vis-NIR spectroscopy (r(2)=0.17), but it can be estimated by EC, using a simple formula. The proposed limit between high and low gustatory index then corresponds to an EC of 5.4 mS/cm. Factor 4, variety, mostly discriminates the pink tomato type and field-grown samples from other varieties. 相似文献