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1.
We explore two methods that correct for differential sampling effort when estimating the true number of species in a region based on samples such as those typically recorded in museum or conservation databases. The two methods are: (1) a phenomenological model that relies on a saturating sampling curve; and (2) a model based on a lognormal distribution of species abundances. We test these methods using a database for the butterflies of Oregon and find that the distribution of high-diversity areas, using the estimated, or “asymptotic”, diversities, is strikingly different from the geographic pattern one would deduce if the raw data were used, without correcting for differential sampling effort. Further, we show that differences in accuracy exist between the two estimation procedures, and that these differences are aggravated at small sample sizes; we argue that estimates based on the lognormal distribution should be preferred because they can offer substantial improvement over analyses based solely on the raw data, generally without risking overestimation. Lastly, using both the database and estimated values of butterfly diversity, we show that the distribution of endangered and numerically rare butterflies rarely coincides with “hotspots” or centers of biodiversity. Thus, protecting regions of Oregon rich in overall butterfly diversity will not normally protect the bulk of rare or endangered butterfly species.  相似文献   
2.
This case report describes tuberculosis (TB) due to infection with Mycobacterium bovis (M. bovis) in alpaca (Lama pacos) on a farm in Ireland. Two severely debilitated alpaca were presented to the University Veterinary Hospital, University College Dublin in November 2004. Bloods were taken, and haematology and biochemistry results were indicative of chronic infection. Radiological examination showed evidence of diffuse granulomatous pneumonia suggestive of tuberculosis. On necropsy there were granulomatous lesions present throughout many body organs including lung, liver, kidney, intestine as well on peritoneum and mesentery. Culture of acid-fast bacilli from lesions led to a diagnosis of tuberculosis due to M. bovis. The use of intradermal skin testing proved inefficient and unreliable for ante mortem diagnosis of tuberculosis in alpaca. Infection due to M. bovis should be considered among the differential diagnoses of debilitating diseases in alpaca, particularly those farmed in areas known to be traditional black spots for tuberculosis in cattle.  相似文献   
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The effect of temperature on the in vitro growth rates and pathogenicity of a European Fusarium collection consisting of isolates of Fusarium graminearum, F. culmorum, F. avenaceum, F. poae and Microdochium nivale was examined. Irrespective of geographic origin, the optimum temperature for the growth of F. graminearum, F. culmorum and F. poae was 25 °C, while that for F. avenaceum and M. nivale was 20 °C. In general, the growth rates of F. graminearum, F. culmorum and F. poae increased between 10 and 25 °C and those of F. avenaceum and M. nivale increased between 10 and 20 °C. Pathogenicity tests were carried out by examining the effect of the five species on the in vitro coleoptile growth rate of wheat seedlings (cv. Falstaff). Irrespective of geographic origin, the temperature at which F. avenaceum, F. culmorum and F. graminearum caused the greatest retardation in coleoptile growth ranges 20–25 °C (>89.3% reduction), whilst for F. poae and M. nivale it was 10–15 °C (>45.6% retardation), relative to uninoculated control seedlings. In general, F. culmorum and F. graminearum were the most pathogenic of the five species, causing at least a 69% reduction in coleoptile growth at 10, 15, 20 and 25 °C. General linear model analysis (GLIM) showed that species accounted for 51.3–63.4% of the variation in isolate growth and from 19.5% to 44.3% of the variation in in vitro pathogenicity. Country of origin contributed from 22.6% to 51.9% to growth rate variation and from 0.73% to 7.61% to pathogenicity variation. The only significant correlation between in vitro growth and pathogenicity was that observed for M. nivale at 15 °C (r = -0.803, P < 0.05).  相似文献   
4.
Dental pulp tissue from three elephants was examined histologically with hematoxylin and eosin and s-100 protein stains. In all specimens, normal pulp was found with the exception that no nerve fibers (myelinated or non-myelinated) were demonstrable in any of the numerous sections prepared.  相似文献   
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Fagan  William F.  Meir  Eli  Carroll  Steven S.  Wu  Jianguo 《Landscape Ecology》2001,16(1):33-39
Data on permits for new housing starts are a key source of information on recent changes in the urban landscape of central Arizona, USA. Drawing primarily on the conceptual parallels between the process of urban expansion and the spatial spread of non-human species, we outline a nested series of 'colonization' models that could be used to study changes in urban landscapes through simulations of housing starts.Within our probabilistic colonization framework, the ecological principle of density-dependence (operating simultaneously on different spatial scales) governs the positioning of new housing units. These simple models afford a great diversity of possible spatial patterns, ranging from tight clustering of houses to urban sprawl to more subtle patterns such as aversion of housing developments from (and aggregation near) different kinds of landscape features. These models can be parameterized from a variety of types of governmental housing data. Ultimately, such a framework could be used to contrast development patterns among cities and identify pertinent operational scales and factors influencing processes associated with urbanization.  相似文献   
7.
An adult male lowland gorilla had been treated with diphenylhydantoin for 6 months following several acute convulsive episodes. The gorilla remained clinically normal during that period. Then, for no apparent reason, it refused its usual diet. Physical examination revealed acute inflammatory gingival hyperplasia. Full mouth gingivectomy and antibiotic and analgesic therapy resolved the oral inflammation and the anorexia.  相似文献   
8.
Tuberculosis (TB), due to infection with Mycobacterium bovis was diagnosed in a flock of alpaca in Ireland in 2004. An epidemiological investigation was conducted to identify the risk of TB for farmed alpaca where TB is endemic, the origin of the infection, the potential for alpaca-to-alpaca transmission and appropriate control measures. The investigation focused on the alpaca flock (including the farm, animal movements and breeding, feeding and flock health practice), the disease episode (including animal disease events and subsequent control measures) and TB infection risk in the locality. The TB risk to alpaca is high in areas where infection is endemic in cattle and badgers and where biosecurity is inadequate. It is most likely that the source of infection for the alpaca was a local strain of M. bovis, present in cattle in this area since at least 2001. Genotyping of isolates identified a single variable number tandem repeat (VNTR) profile in both cattle and alpaca in this region. Although a tuberculous badger was also removed from the vicinity, bacterial isolation was not attempted. On this farm, infection in alpaca was probably derived from a common source. Alpaca-to-alpaca transmission seems unlikely. Two broad control strategies were implemented, aimed at the rapid removal of infected (and potentially infectious) animals and the implementation of measures to limit transmission. Tests that proved useful in detecting potentially-infected animals included measurement of the albumin-to-globulin ratio and regular body condition scoring. Skin testing was time consuming and unproductive, and early detection of infected animals remains a challenge. The flock was managed as a series of separate groupings, based on perceived infection risk. No further TB cases have been detected.  相似文献   
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The cheese industry has continually sought a robust method to monitor milk coagulation. Measurement of whey separation is also critical to control cheese moisture content, which affects quality. The objective of this study was to demonstrate that an online optical sensor detecting light backscatter in a vat could be applied to monitor both coagulation and syneresis during cheesemaking. A prototype sensor having a large field of view (LFV) relative to curd particle size was constructed. Temperature, cutting time, and calcium chloride addition were varied to evaluate the response of the sensor over a wide range of coagulation and syneresis rates. The LFV sensor response was related to casein micelle aggregation and curd firming during coagulation and to changes in curd moisture and whey fat contents during syneresis. The LFV sensor has potential as an online, continuous sensor technology for monitoring both coagulation and syneresis during cheesemaking.  相似文献   
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