全文获取类型
收费全文 | 253篇 |
免费 | 9篇 |
专业分类
林业 | 6篇 |
农学 | 9篇 |
31篇 | |
综合类 | 61篇 |
农作物 | 11篇 |
水产渔业 | 3篇 |
畜牧兽医 | 129篇 |
园艺 | 4篇 |
植物保护 | 8篇 |
出版年
2023年 | 2篇 |
2020年 | 8篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 9篇 |
2013年 | 9篇 |
2012年 | 10篇 |
2011年 | 8篇 |
2010年 | 12篇 |
2009年 | 4篇 |
2008年 | 8篇 |
2007年 | 9篇 |
2006年 | 7篇 |
2005年 | 11篇 |
2004年 | 8篇 |
2003年 | 13篇 |
2002年 | 9篇 |
2001年 | 4篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1986年 | 7篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1972年 | 2篇 |
1970年 | 3篇 |
1967年 | 3篇 |
1966年 | 3篇 |
1954年 | 2篇 |
1930年 | 2篇 |
1928年 | 4篇 |
1910年 | 2篇 |
1892年 | 1篇 |
1888年 | 1篇 |
1885年 | 1篇 |
1884年 | 8篇 |
1883年 | 6篇 |
排序方式: 共有262条查询结果,搜索用时 62 毫秒
101.
Geun‐Pyo Hong Nicole Avramenko Andrea Stone Dawn Abbott Hank Classen Michael Nickerson 《Cereal Chemistry》2012,89(6):276-283
Extractability and molecular modifications of gliadin and glutenin proteins withdrawn from different stages of a commercial ethanol fuel/distillers dried grains with solubles (DDGS) process using a wheat feedstock were investigated. Materials were taken postliquefaction (PL), postdistillation (whole stillage), and postdrying (DDGS) during the process and then fractionated to separate the gliadins and the soluble high‐ and low‐molecular‐weight glutenins following a modified Verbruggen extraction method. Each fraction was characterized based on the extraction efficiencies within various aqueous alcohols of propan‐1‐ol, electrophoretic patterns, intrinsic and extrinsic fluorescence, free and total sulfhydryl content, and total disulfide bond levels. Findings indicated significant changes to the composition of extracted proteins and modifications to the protein structure (i.e., surface properties and conformation) throughout the ethanol/DDGS process, beginning with the first step of production (PL, ≈83°C). Overall, processing resulted in a shift toward an unextractable gluten matrix, accompanied by increases in hydrophobicity, disulfide bridging, and excessive protein aggregation. 相似文献
102.
Sanjutha Shanmugam Lynette K. Abbott Daniel V. Murphy 《Biology and Fertility of Soils》2014,50(7):1047-1059
The addition of clay to lime-amended biosolids has been proposed as a soil amendment (LaBC®) for remediating acidic-sandy soil. We investigated whether the presence of clay in LaBC® altered soil microbial processes over a 30-week period. Aerobic-incubation and CO2 respiration assays were used to monitor water repellence and chemical and microbiological properties of amended soil. Dry LaBC® was applied at equivalent wet weight of 50, 100 and 150 t ha?1. In addition, dry components of LaBC® (lime, clay, lime + clay (LAC) and lime + biosolids (LAB)) were applied separately at rates equivalent to their fractions within LaBC®. Inclusion of clay in LaBC® was effective in eliminating water repellence at all application rates. Inclusion of clay in LaBC® decreased nitrogen (N) release from the biosolids (by 58 %), even at 50 t ha?1, but only during the first 2 weeks of incubation. LaBC® consistently decreased soil microbial respiration compared with LAB alone when applied at 150 t ha?1 thereby protecting organic matter decomposition. There was no significant N release with lime and clay amendment alone or in combination (LAC) in the absence of the biosolids. There may be a complex interaction between clay, lime and organic matter, but each may have had a role in altering N release from biosolids at different times during the 30-week incubation. Addition of clay to LAB increased its effectiveness in remediating this water-repellent, acidic-sandy soil and prolonged the N release from the biosolids following soil amendment. 相似文献
103.
Erin N. Kishi Shannon P. Holmes Jeffrey R. Abbott Nicholas J. Bacon 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(4):383-388
A 12-year-old dachshund dog was presented for persistent hypercalcemia and hyperparathyroidism despite bilateral parathyroidectomy. Magnetic resonance imaging of the head, neck, and cranial mediastinum identified an increased number of cranial mediastinal lymph nodes with heterogeneous signal intensity. Hypercalcemia and hyperparathyroidism resolved after surgery to remove multiple cranial mediastinal lymph nodes, one of which contained presumed metastatic parathyroid tissue. 相似文献
104.
Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy (SEM) observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEM than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization ofbiochar from hyphae in the agricultural soil used in this study. 相似文献
105.
OBJECTIVES: To compare the family, educational and animal-related backgrounds and career aspirations of students who were selected on the basis of academic criteria with those selected using additional criteria. METHODS: Questionnaires were completed during class time in the first few weeks of enrolment by incoming veterinary students at the University of Sydney, who had been selected on the basis of academic background, and at Charles Sturt University, selected using more broadly-based criteria. The data were transferred to an Excel spreadsheet, and frequency distributions and chi2 statistics estimated using the SAS System for Windows 8. RESULTS: Students selected principally on academic criteria alone had higher average UAI scores, were more likely to have completed high school in a capital city, and to have parents with higher education levels than those selected using additional criteria. Both groups indicated that their choice of veterinary science was based largely on their affinity for animals and keenness to work in a veterinary practice. However, those at CSU placed much greater importance than those at Sydney on a desire to live and work in a rural area, and a desire to help farmers. The broad-based selection methods were the main reasons for students applying to CSU whereas the reputation of the university was the main attraction for Sydney students. Two-thirds of CSU students, but one-third of Sydney students, planned to enter rural mixed practice when they graduated, and most planned to stay for at least 10 years. Conversely, no CSU students, but 42% of those at Sydney, planned to enter small animal practice initially. The percentage planning to work full-time in the first, fifth and tenth year after graduation was not significantly different between the two groups. CONCLUSIONS: Criteria which included actual experience with farm animals have resulted in the selection of more students who plan to enter and remain in rural mixed practice. Further studies over the longer term will be necessary to assess the extent to which these plans are realized. 相似文献
106.
MacLean HN Abbott JA Ward DL Huckle WR Sisson DD Pyle RL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(2):284-289
Atrial natriuretic peptide (ANP) is an important regulator of fluid homeostasis and vascular tone. We sought to compare N-terminal ANP immunoreactivity (ANP-IR) in plasma from cats with and without hypertrophic cardiomyopathy (HCM). Secondarily, we evaluated relationships between ANP-IR and echocardiographical variables in cats with HCM and healthy cats. Venous blood samples were obtained from 17 cats with HCM and from 19 healthy cats. Plasma ANP-IR concentration was determined by an enzyme-linked immunoassay. Two cats with HCM had clinical evidence of congestive heart failure; the remainder had subclinical disease. Plasma ANP-IR concentration was higher in cats with HCM (3,808 +/- 1,406 fmol/L, mean +/- SD) than in control cats (3,079 +/- 1,233 fmol/L), but this difference was not statistically significant (P = .11; 95% confidence interval [CI] = -166 to 1,622). There was a significant, but modest correlation between plasma ANP-IR concentration and left ventricular posterior wall thickness (r = 0.42; P = .01). Additionally, plasma ANP-IR concentration was weakly correlated with left atrial size (r = 0.35; P = .03). A linear regression model was developed to further explore these relationships. Atrial size and wall thickness were included in the model; the 2 explanatory variables had an interactive effect on plasma ANP-IR concentration (R2 = 0.27; P = .02). There was no appreciable correlation between plasma ANP-IR concentration and any other echocardiographical variable. In a population that included cats with subclinical disease, those with HCM did not have significantly higher plasma ANP-IR concentration than did healthy cats. An exploratory multivariable regression analysis suggested a linear relationship between ANP-IR concentration and atrial size, wall thickness, and their interaction. 相似文献
107.
Rice CP Baldwin Vi RL Abbott LC Hapeman CJ Capuco AV Le A Bialek-Kalinski K Bannerman DD Hare WR Paape MJ McCarty GW Kauf AC Sadeghi AM Starr JL McConnell LL Van Tassell CP 《Journal of agricultural and food chemistry》2007,55(21):8806-8813
Perchlorate has been detected in U.S. milk samples from many different states. Applying data from a recently reported 9-week experiment in which 16 Holstein dairy cows were administered perchlorate allowed us to derive an equation for the dose-response relationship between perchlorate concentrations in feed/drinking water and its appearance in milk. Examination of background concentrations of perchlorate in the total mixed ration (TMR) fed in addition to the variable dose supplied to treated cows as a ruminal infusate revealed that cows receive significant and variable exposure to perchlorate from the TMR. Weekly examination of the TMR disclosed that a change in ingredients midway through the experiment caused a significant (78%) change in TMR perchlorate concentration. Analyses of the ingredients comprising the TMR revealed that 41.9% of the perchlorate came from corn silage, 22.9% came from alfalfa hay and 11.7% was supplied by sudan grass. Finally, USDA Food and Nutrition Survey data on fluid milk consumption were used to predict potential human exposure from milk that contained concentrations of perchlorate observed in our previous dosing study. The study suggests that reducing perchlorate concentration in dairy feed may reduce perchlorate concentrations in milk as well as the potential to reduce human exposure to perchlorate in milk. 相似文献
108.
Biermann F Abbott K Andresen S Bäckstrand K Bernstein S Betsill MM Bulkeley H Cashore B Clapp J Folke C Gupta A Gupta J Haas PM Jordan A Kanie N Kluvánková-Oravská T Lebel L Liverman D Meadowcroft J Mitchell RB Newell P Oberthür S Olsson L Pattberg P Sánchez-Rodríguez R Schroeder H Underdal A Vieira SC Vogel C Young OR Brock A Zondervan R 《Science (New York, N.Y.)》2012,335(6074):1306-1307
109.
110.