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1.
A retrospective analysis of the metabolizable energy (ME) intake of privately owned pet cats from the authors’ nutrition consultation practice (years 2007–2011) was carried out to test whether current recommendations are suitable for pet cats. Data of 80 adult cats (median age: 9.0 years, median deviation from ideal weight: +22.5%, majority neutered) at maintenance were available. Six percentage of the cats were healthy and the others were affected by various chronic diseases. A standardized questionnaire was used, cat owners weighed cat and food. For ration calculation, the software Diet Check Munich? was used (ME prediction according to National Research Council, 2006: Nutrient Requirements of Dogs and Cats. National Academy Press, Washington, DC). Data were analysed for the factors deviation from ideal weight, breed, age, gender, disease and type of feeding [prepared food (dry, wet) vs. home‐made]. Over‐ or underweight were defined as ≥15% deviation from ideal body weight (BW) according to Kienzle and Moik (British Journal of Nutrition 2011, 106, Suppl 1: S113). Cat owner's estimation of ideal BW was higher than literature data from Kienzle and Moik (2011). Based on literature data, 26.3% of the pet cats were normal weight, 63.7% overweight and 10% underweight. The mean ME intake of all adult cats amounted to 0.40 ± 0.14 MJ/kg actual BW0.67 (n = 80). When the data were analysed according to normal, over‐ and underweight, there was a significant effect with normal weight cats eating 0.46 MJ/kg BW0.67. Underweight cats ate even more (0.49 MJ/kg BW0.67), whereas overweight cats ate considerably less (0.36 MJ/kg BW0.67). The other factors had no influence on ME intake of adult cats.  相似文献   
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To determine the role of the spleen in the pathogenesis of canine visceral leishmaniasis (CVL), we analyzed cellular immunophenotypic profiles of 52 dogs naturally infected with Leishmania infantum, clinically classified as follows: asymptomatic dogs-I (AD-I), seronegative/PCR+; asymptomatic dogs-II (AD-II), seropositive/PCR+; oligosymptomatic dogs (OD) and symptomatic dogs (SD). Seven non-infected dogs (CD) were included as a control group. AD-II presented higher levels of CD8+ T splenocytes and lower TCD4+/TCD8+ ratio in comparison with CD. OD and SD showed lower percentages of CD21+ as compared with AD-II. All seropositive dogs presented lower levels of CD45RA+ than CD. Regardless of the stimuli used, the proliferation index from splenocytes in vitro was inversely correlated with clinical status. After LSA stimulation, there was a higher percentage of specific CD8+ T in AD-II than CD and non-stimulated culture. In contrast, splenocytes from SD under in vitro LSA stimulation induced decreased MHC-II+ expression in comparison with all groups, and non-stimulated culture. In conclusion, the role of CD8+ T splenocytes seems to be important for an effective immunological response, a hallmark of asymptomatic CVL, whereas the pronounced loss of MHC-II expression upon LSA stimulation is a biomarker of symptomatic CVL.  相似文献   
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The Ecological Areawide Management (TEAM) Leafy Spurge project is a United States Department of Agriculture and Agricultural Research Service (USDA–ARS) regional, Integrated Pest Management (IPM) program focused on the Little Missouri River drainage in the states of North and South Dakota, Montana, and Wyoming, U.S.A. TEAM Leafy Spurge project represents the first large-scale, systematic study and demonstration of weed management alternatives under USDA–ARS's Areawide Pest Management Program. The other three projects previously approved under the program targeted insect pests. TEAM Leafy Spurge's primary goal has been to demonstrate the use of ecologically based IPM strategies to achieve effective, affordable leafy spurge control. TEAM Leafy Spurge is co-chaired and overseen by the USDA–ARS in cooperation with the USDA–Animal and Plant Health Inspection Service. Both agencies have many years of experience in research and implementation of leafy spurge control tactics as well as valuable contacts and resources. Together those federal partners make a powerful team to address the leafy spurge problem on a multi-state basis. Additional federal agencies participating in TEAM Leafy Spurge include: Bureau of Land Management, U.S. Forest Service, National Park Service, Bureau of Indian Affairs, Bureau of Reclamation, and U.S. Geological Service. State partners include: state departments of agriculture and other state agencies, Cooperative Extension Services, land grant universities, and county weed managers, while private sector representatives include landowners and ranchers. A non-partisan ad hoc committee consisting of state and federal researchers, land managers, representatives from local, state, and federal entities, and private landowners/ranchers provides guidance and helps to ensure the quality and applicability of the program. The extensive partnerships are of particular importance because they help to ensure continued dissemination of information past the limited life span of TEAM Leafy Spurge, which is set to expire in 2003.The five components of TEAM Leafy Spurge research and demonstration project are: (1) Program management; (2) Operations; (3) Assessment; (4) Supporting research, and (5) Technology transfer. As of this writing, the bulk of the research work has been completed and now TEAM Leafy Spurge is focusing its energies on assessment and technology transfer projects. Where available, brief outlines of research results are included here in addition to discussion of the program's key components, overall structure and general operation.  相似文献   
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Dehydroleucodine (DhL), a sesquiterpene lactone obtained from Artemisia douglasiana, was screened for antidiarrheal effects. DhL inhibited castor oil-induced diarrhea in mice by judged by a decrease in the number of wet faeces in the DhL-treatment groups. DhL significantly reduced intestinal transit in mice. Yohimbine and phentolamine counteracted the inhibitory effect of DhL. It is suggested that alpha(2)-adrenergic receptors mediate the effect of DhL in intestinal motility. DhL reduced also intraluminal accumulation of fluid. Thus, the antidiarrheal activity of DhL is possibly related, at least in part, to its inhibitory action against gastrointestinal motility and the inhibition of enteropooling property.  相似文献   
6.
Journal of Soils and Sediments - The concentration and spatial distribution of many potentially toxic elements (PTEs) have not been studied in the mining areas of tropical soils in the Amazon. The...  相似文献   
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Paleolimnological techniques were utilized to determine whether diatom and scaled chrysophyte assemblages in Daisy, Swan, and Tilton lakes (Sudbury, Ontario) have recovered toward their preimpact conditions as a result of reduced inputs of anthropogenic pollutants (SO 4 2? and metals) or whether other environmental stressors have affected recovery trajectories. In addition, geochemical analysis was used to track trends in sedimentary nickel and copper concentrations through time. Preindustrial algal assemblages were primarily dominated by circumneutral to alkaline and pH-indifferent taxa. However, with the onset of open-pit roasting and smelting operations, there was a stratigraphic shift toward acid-tolerant species. With wide-scale smelter emission reductions commencing in the 1970s, scaled chrysophyte assemblages in Swan and Daisy lakes have started to show signs of biological recovery in ~1984 and ~1991, respectively. Although the scaled chrysophyte assemblage in Tilton Lake has not recovered toward the predisturbance assemblage, the decline in acidophilic taxa and increase in circumneutral taxa in recently deposited lake sediments indicate that the community is responding to increased lake water pH. Conversely, diatom assemblages within each of the study lakes have not begun to recover, despite well-documented chemical recovery. It is suspected that biological recovery in Sudbury area lakes may be impeded by other environmental stressors such as climate warming. Copper and nickel concentrations in lake sediments increased with the onset of mining activities and subsequently declined with emission controls. However, metal concentrations in lake sediments remain elevated compared to preindustrial concentrations. Together, biological and geochemical evidence demonstrates the clear environmental benefits associated with smelter emission controls.  相似文献   
9.
Taxonomic understanding is a necessary prerequisite for intelligent germplasm maintenance and evaluation. Here, we use molecular evidence to address the generic position of the poorly known and morphologically unusual taxon Gossypium trifurcatum Vollesen. This species possesses dentate leaves, a feature not otherwise found in Gossypium L. but one that is common in Cienfuegosia Cav., a related genus in the small Malvaceous tribe Gossypieae. G. trifurcatum is a rare plant, restricted to deserts of Eastern Somalia and known from only two collections, the last in 1980. Using DNA extracted from an herbarium specimen, we amplified and sequenced the chloroplast gene ndhF. Phylogenetic analysis reveals G. trifurcatum to be cladistically nested within Gossypium. These data diagnose dentate leaves as an autapomorphy within a genetically diverse assemblage of African–Arabian species, which remain the least well-represented cottons in germplasm collections.  相似文献   
10.
Molecular analysis, serology and immunophenotyping for T lymphocytes and their subsets, B lymphocytes and monocytes were performed on dogs naturally infected with Leishmania infantum. Animals were categorised as asymptomatic dogs I (AD-I), with negative serology and positive molecular results, and asymptomatic dogs II (AD-II), with positive serology and positive molecular results, and these were compared to symptomatic dogs (SD) and control dogs (CD). AD-I exhibited immunophenotypic features similar to those of CD, including isotype profiles and concentrations of monocytes. Similar biomarkers were found in AD-II and SD, such as, higher levels of immunoglobulins IgG, IgG2, IgM and IgA and higher concentrations of eosinophils. High frequencies of T lymphocytes and CD4(+) T cells were observed in both AD-I and AD-II compared to SD, whereas CD8(+) T cells were higher only in AD-II compared with SD. Analysis of B lymphocytes revealed an increased frequency of this cell type only in AD-II animals compared with SD. Asymptomatic dogs appear to have a dichotomous infection spectrum that can influence the humoral and cellular immunological status during canine visceral leishmaniasis.  相似文献   
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