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111.
Quantifying the historical range and variability of landscape composition and structure using simulation modeling is becoming an important means of assessing current landscape condition and prioritizing landscapes for ecosystem restoration. However, most simulated time series are generated using static climate conditions which fail to account for the predicted major changes in future climate. This paper presents a simulation study that generates reference landscape compositions for all combinations of three climate scenarios (warm-wet, hot-dry, and current) and three fire regime scenarios (half historical, historical, and double historical fire frequencies) to determine if future climate change has an effect on landscape dynamics. We applied the spatially explicit, state-and-transition, landscape fire succession model LANDSUM to two large landscapes in west-central Montana, USA. LANDSUM was parameterized and initialized using spatial data generated from the LANDFIRE prototype project. Biophysical settings, critical spatial inputs to LANDSUM, were empirically modeled across the landscape using environmental gradients created from historical and modeled future climate daily weather data summaries. Successional pathways and disturbance probabilities were assigned to these biophysical settings based on existing field data and extensive literature reviews. To assess the impact of changes in climate and fire regime, we compared simulated area burned and landscape composition over time among the different simulation scenario combinations using response variables of Sorenson's index (a global measure of similarity) and area occupied by the dominant vegetation class (simple indicator of change in landscape composition). Results show that simulated time series using future predicted climate scenarios are significantly different from the simulated historical time series and any changes in the fire regime tend to create more dissimilar and more variable simulated time series. Our study results indicate that historical time series should be used in conjunction with simulated future time series as references for managing landscapes. 相似文献
112.
Amy Trauger Carolyn Sachs Mary Barbercheck Kathy Brasier Nancy Ellen Kiernan 《Agriculture and Human Values》2010,27(1):43-55
Civic agriculture is characterized in the literature as complementary and embedded social and economic strategies that provide
economic benefits to farmers at the same time that they ostensibly provide socio-environmental benefits to the community.
This paper presents some ways in which women farmers practice civic agriculture. The data come from in-depth interviews with
women practicing agriculture in Pennsylvania. Some of the strategies women farmers use to make a living from the farm have
little to do with food or agricultural products, but all are a product of the process of providing a living for farmers while
meeting a social need in the community. Most of the women in our study also connect their business practices to their gender
identity in rural and agricultural communities, and redefine successful farming in opposition to traditional views of economic
rationality. 相似文献
113.
114.
Woodpeckers (family Picidae) show promise as indicators of avian diversity in forests because their populations can be reliably monitored, and their foraging and nesting activities can positively influence the abundance and richness of other forest birds. A correlation between woodpecker richness and richness of forest birds is known to exist at the landscape scale, but uncertainty remains whether this correlation occurs at the smaller stand-level spatial scales where forest management activities take place. We used data collected under a diverse range of forest types, harvest treatments, and forest health conditions during a long-term study of bird communities in interior British Columbia, Canada, to examine two basic questions: (1) at the level of individual forest stands, is woodpecker richness correlated with bird richness (measured as richness of all other bird species)? and (2) do woodpecker richness and bird richness have similar habitat correlates? Bird richness was positively correlated with woodpecker richness (β = 0.59, SE = 0.22, 95% CI = [0.14 1.03]). Richness of both woodpeckers and all other birds were positively correlated with tree species richness and negatively correlated with density of pines, and the effect for forest harvest type was similar for both measures of avian richness (uncut < partial harvest < clearcut with reserves). The effect of density of lodgepole pines killed by mountain pine beetles differed between the two richness measures, being positive for woodpecker richness and negative for forest bird richness. We conclude that the richness of woodpeckers is indeed correlated with the richness of other birds at the stand-level, and can serve as a reliable indicator of overall bird richness in most forest stands and conditions, except during insect outbreaks when differential responses by woodpeckers and the rest of the avian community may decouple the relationship between bird richness and woodpecker richness. 相似文献
115.
Pollard CM Miller MR Daly AM Crouchley KE O'Donoghue KJ Lang AJ Binns CW 《Public health nutrition》2008,11(3):314-320
OBJECTIVE: The Western Australian Health Department's Go for 2&5 campaign aimed to increase adults' awareness of the need to eat more fruit and vegetables and encourage increased consumption of one serving over five years. DESIGN: The multi-strategy fruit and vegetable social marketing campaign, conducted from 2002 to 2005, included mass media advertising (television, radio, press and point-of-sale), public relations events, publications, a website (www.gofor2and5.com), and school and community activities. Campaign development and the evaluation framework were designed using health promotion theory, and assessed values, beliefs, knowledge and behaviour. Two independent telephone surveys evaluated the campaign: the Campaign Tracking Survey interviewed 5032 adults monitoring fruit and vegetable attitudes, beliefs and consumption prior to, during and 12 months after the campaign; and the Health & Wellbeing Surveillance System surveyed 17,993 adults between 2001 and 2006, continuously monitoring consumption. SETTING: Population public health intervention-social marketing campaign in Western Australia, population of 2,010,113 in 2005. SUBJECTS: Adults in the Perth metropolitan area. RESULTS: The campaign reached the target audience, increasing awareness of the recommended servings of fruit and vegetables. There was a population net increase of 0.8 in the mean number of servings of fruit and vegetables per day over three years (0.2 for fruit (1.6 in 2002 to 1.8 in 2005) and 0.6 for vegetables (2.6 in 2002 to 3.2 in 2005), significant at P < 0.05). CONCLUSION: Sustained, well-executed social marketing is effective in improving nutrition knowledge, attitudes and consumption behaviour. The Go for 2&5 campaign provides guidance to future nutrition promotion through social marketing. 相似文献
116.
Serum Fructosamine Concentration as an Index of Glycemia in Cats With Diabetes Mellitus and Stress Hyperglycemia 总被引:2,自引:0,他引:2
Kathy L. Crenshaw Mark E. Peterson DVM Laurie A. Heeb Scott D. Moroff Rhett Nichols 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(6):360-364
The purpose of this study was to evaluate fructosamine concentrations in clinically healthy cats, sick cats with stress hyperglycemia, and untreated diabetic cats to determine the usefulness of this test in diagnosing diabetes mellitus in cats, and in differentiating the disease from stress-induced hyperglycemia. In addition, we evaluated if the degree of glycemic control in cats treated for diabetes influenced their serum fructosamine concentrations. In the 14 sick cats with stress hyperglycemia, the median serum fructosamine concentration (269 μmol/L) was not significantly different from the median value in the 26 clinically normal cats (252 μmol/L). Two of the 14 cats with stress hyperglycemia (14.3%) had serum fructosamine concentrations above the upper limit of the reference range (175 to 400 μmol/U; on the basis of these results, the test specificity was calculated as 0.86. In 30 cats with untreated diabetes mellitus, the median serum fructosamine concentration was 624 μmol/L, markedly higher than the value in either the normal cats or the cats with stress hyperglycemia. All but 2 of the 30 untreated diabetic cats (6.7%) had serum fructosamine concentration above the upper limit of the reference range; on the basis of these results, the sensitivity of serum fructosamine concentration as a diagnostic test for diabetes mellitus was 0.93. When 30 diabetic cats receiving treatment were divided into 3 groups according to their response to treatment (ie, poor, fair, and good), the 16 cats that had a good response to treatment had significantly lower serum concentrations of both glucose and fructosamine compared with cats that had either a fair or poor response to treatment. A significant correlation (rs= .70, n = 100, P < .001) was found between serum concentrations of glucose and fructosamine. Results of this study indicate that quantification of serum fructosamine concentration is a meaningful test for the diagnosis of diabetes, for differentiating diabetes from stress hyperglycemia; and for monitoring the metabolic control in treated diabetic cats. 相似文献
117.
AIfred M. Legendre DVM MS Kathy L. Mitchener DVM Leon N. D. Potgieter BVSc MS PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1990,4(2):92-98
A commercial feline leukemia virus (FeLV) vaccine was evaluated in a natural exposure system. All kittens were negative for FeLV antigen on two enzyme-linked immunosorbent assay (ELISA) tests and one indirect immunofluorescence antibody (IFA) test before vaccination or exposure. Twenty-three kittens were vaccinated subcutaneously at nine and 12 weeks of age. The vaccinated kittens and 14 unvaccinated littermates were housed in an infected environment starting at 14 weeks. The kittens were exposed for 24 weeks by living in a large room with one feline leukemia virus-positive, asymptomatic adult cat for each five kittens. Sixty-four percent of the unvaccinated kittens and 70% of the vaccinated kittens became infected as determined by ELISA. Forty-three percent of unvaccinated kittens and 39% of vaccinated kittens died. There was no difference between the infection and mortality of vaccinated kittens that developed antibodies to anti-FeLV glycoprotein 70-envelope antigen and those that did not. Consideration should be given to evaluation of feline leukemia virus vaccines using "street" virus in a natural exposure system. 相似文献
118.
119.
120.
Khoo C Cunnick J Friesen K Gross KL Wedekind K Jewell DE 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(1):43-56
The objective of this study was to evaluate the effect of supplementary antioxidants (AOX) and whey protein on the immune function health of puppies. Four groups of 10 puppies were fed a control and 3 different test foods (control + antioxidants (AOX), control + AOX + 1% whey protein, and a grocery brand (low AOX)) for 6 weeks. A standard vaccination protocol with a combination canine parvovirus (CPV) and distemper (CDV) vaccine was carried out at 2 and 4 weeks. The results showed that animals on high AOX foods had significantly increased titers, memory cells and serum E concentrations compared to the control and groc groups respectively. 相似文献