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61.
62.
A strip-tillage production system for tomatoes (Lycopersicon esculentum Mill.) is impacted by nutrient competition from bahiagrass (Paspalum notatum Flügge). Tomato and bahiagrass differ in mycorrhizal responsiveness and our objective was to evaluate the influence of arbuscular mycorrhizal (AM) fungi on the competitive pressure of bahiagrass on growth of tomato. The first experiment evaluated the effect of bahiagrass competition, soil pasteurization, and AM fungal inoculation on tomato growth, P content, and root colonization in a low-P soil. Tomato grown alone was very responsive to mycorrhizal colonization - shoot dry mass of inoculated plants was up to 243% greater than that of noninoculated plants. Tomato grown with bahiagrass had reduced root and shoot growth across all treatments compared with tomato grown alone, but there was an increase in shoot mass following AM fungal inoculation across both pasteurized and nonpasteurized treatments resulting in a >50% increase in shoot dry mass of tomato compared to noninoculated controls. A second experiment was conducted to test bahiagrass competition, soil pasteurization, AM fungal inoculation, and P amendment on tomato growth in a moderate-P soil. With bahiagrass competition and no P addition, inoculation increased root mass by 115% and shoot mass by 133% in pasteurized soil; however, with the application of 32 mg P kg-1 the trend was reversed and inoculated plants were smaller than noninoculated controls. We conclude that the role of mycorrhizae in plant competition for nutrients is markedly impacted by soil nutrient status and reduced P application may allow tomatoes to take advantage of their inherent responsiveness to mycorrhizae in a low to moderate soil-P environment. 相似文献
63.
64.
Development in organic farming has been stimulated by farmers and consumers becoming interested in healthy food products and
sustainable environment. Organic agriculture is a holistic production management system which is based on the principles of
health, ecology, care, and fairness. Organic development in Uganda has focused more on the crop sector than livestock sector
and has primarily involved the private sector, like organic products export companies and non-governmental organizations.
Agriculture in Uganda and many African countries is predominantly traditional, less mechanized, and is usually associated
with minimum use of chemical fertilizers, pesticides, and drugs. This low external input agriculture also referred to as “organic
by default” can create basis for organic farming where agroecological methods are introduced and present an alternative in
terms of intensification to the current low-input/low-output systems. Traditional farming should not be confused with organic
farming because in some cases, the existing traditional practices have consequences like overstocking and less attention to
soil improvement as well as to animal health and welfare, which is contrary to organic principles of ecology, fairness, health,
and care. Challenges of implementing sustainable organic practices in the Ugandan livestock sector threaten its future development,
such as vectors and vector-borne diseases, organic feed insufficiency, limited education, research, and support to organic
livestock production. The prospects of organic livestock development in Uganda can be enhanced with more scientific research
in organic livestock production under local conditions and strengthening institutional support. 相似文献
65.
Effects of road type during transport on lamb welfare and meat quality in dry hot climates 总被引:1,自引:1,他引:0
Miranda-de la Lama GC Monge P Villarroel M Olleta JL García-Belenguer S María GA 《Tropical animal health and production》2011,43(5):915-922
This study determined whether transporting lambs on paved (PR) or unpaved roads (UR) for 3 h had an effect on plasma stress
indicators (cortisol, lactate, glucose, creatine kinase [CK], red blood cells, white blood cells, hematocrit, and neutrophil/lymphocyte
[N/L] ratio) and instrumental meat quality (pH24, bruising score, water holding capacity [WHC], color, and texture). A total
of 48 Rasa Aragonesa male lambs were used that were approximately 100 days old (12.5 kg ± 1.64, carcass weight). The results
suggest that transport on unpaved roads had a significant influence on physiological and hematological stress parameters.
Road type had a significant effect on all variables, except for white and red blood cells, and hematocrit levels. The UR lambs
had significantly higher (at least p ≤ 0.01) cortisol, lactate, glucose, and CK levels and a higher N/L ratio than PR lambs. Meat from UR lambs had some dark-cutting
characteristics, with a darker color, higher ultimate pH, and higher tenderness values than PR. In conclusion, lambs transported
on unpaved roads had a more intense stress response and poorer meat quality than lambs transported on paved roads. An effort
to improve the logistics associated with route planning is necessary to prevent welfare problems during transport to slaughter. 相似文献
66.
Djajadiningrat-Laanen S Galac S Kooistra H 《Journal of Feline Medicine and Surgery》2011,13(9):641-650
PRACTICAL RELEVANCE: Primary hyperaldosteronism is probably the most common adrenocortical disorder in cats. As in humans, it is often unrecognised, which excludes a potentially large number of cats from appropriate treatment. PATIENT GROUP: Affected cats present at a median age of 13 years (range 5-20 years). A breed or sex predilection has not been documented. The excessive secretion of mineralocorticoids usually leads to hypokalaemia and/or systemic arterial hypertension. Most affected cats present with muscular weakness and/or ocular signs of arterial hypertension. DIAGNOSTICS: In any cat presenting with hypokalaemia and/or arterial hypertension, other potential causes should be excluded. The ratio of plasma aldosterone concentration to plasma renin activity (aldosterone:renin ratio) is currently the best screening test for feline primary hyperaldosteronism. Diagnostic imaging is required to differentiate between adrenocortical neoplasia and bilateral hyperplasia, and to detect any distant metastases. CLINICAL CHALLENGES: The differentiation between adrenocortical neoplasia and bilateral hyperplasia is imperative for planning optimal therapy, but the limited sensitivity of diagnostic imaging may occasionally pose a problem. For confirmed unilateral primary hyperaldosteronism, unilateral adrenalectomy is the treatment of choice, and offers an excellent prognosis, but potentially fatal intra- and postoperative haemorrhage is a reported complication and risk factors have yet to be identified. EVIDENCE BASE: Only a few case reports are available on which to base the optimal diagnostic and therapeutic approach to feline primary hyperaldosteronism. This article reviews the physiology of aldosterone production and the pathophysiology of primary hyperaldosteronism, and summarises the currently available literature on the feline disease. Practical suggestions are given for the diagnostic investigation of cats with suspected primary hyperaldosteronism. 相似文献
67.
Digangi BA Gray LK Levy JK Dubovi EJ Tucker SJ 《Journal of Feline Medicine and Surgery》2011,13(12):912-918
Serum antibody titers are a useful measurement of protection against infection (feline panleukopenia virus [FPV]) or clinical disease (feline herpesvirus-1 [FHV] and feline calicivirus [FCV]), and their determination has been recommended as part of disease outbreak management in animal shelters. The objective of this study was to determine the sensitivity, specificity, and inter-observer and inter-assay agreement of two semi-quantitative point-of-care assays for the detection of protective antibody titers (PAT) against FPV, FHV and FCV in shelter cats. Low sensitivity for FPV antibodies (28%) rendered a canine point-of-care assay inappropriate for use in cats. The feline point-of-care assay also had low sensitivity (49%) and low negative predictive value (74%) for FPV PAT detection, but was highly accurate in the assessment of FHV and FCV PAT. Improvements in accuracy and repeatability of FPV PAT determination could make this tool a valuable component of a disease outbreak response in animal shelters. 相似文献
68.
Modeling the impact of global change on regional agricultural land use through an activity-based non-linear programming approach 总被引:1,自引:0,他引:1
Martin Henseler Alexander Wirsig Sylvia Herrmann Tatjana Krimly Stephan Dabbert 《Agricultural Systems》2009,100(1-3):31-42
Assessing the impact of climate change on agriculture is a new challenge for quantitative model-based policy analysis. The impact of climate change will vary strongly across regions depending on pre-existing climatic, agronomic, and political conditions. Most of the present modeling approaches, which aim to analyze the impact of global change on agriculture, deliver aggregated results both with regard to content and spatial resolution. To deliver results with a higher spatial resolution and to produce a more detailed picture of agricultural production, the county-based agro-economic model known as ACRE-Danube was developed. The German and Austrian part of the Upper Danube basin, a study area with great diversity in agricultural landscapes and climatic conditions, was chosen for study. For the analysis, two scenarios of climatic and socio-economic change were derived. The first and more economically and globally oriented scenario, termed “Full Liberalization,” included significant temperature increases. The second and more environmentally and regionally oriented “Full Protection” scenario included a moderate temperature increase. Both scenarios produce different results regarding agricultural income and land use. While the developments in the Full Protection scenario are small, the Full Liberalization scenario yields extreme regional changes in agricultural income, an increase in cereal production and extensive grassland farming. 相似文献
69.
Patterson EV Reese MJ Tucker SJ Dubovi EJ Crawford PC Levy JK 《Journal of the American Veterinary Medical Association》2007,230(3):359-363
OBJECTIVE: To determine the frequency and duration of feline panleukopenia virus (FPV) vaccine-induced interference with fecal parvovirus diagnostic testing in cats. DESIGN: Prospective controlled study. ANIMALS: Sixty-four 8- to 10-week-old specific-pathogen-free kittens. PROCEDURES: Kittens were inoculated once with 1 of 8 commercial multivalent vaccines containing modified-live virus (MLV) or inactivated FPV by the SC or intranasal routes. Feces were tested for parvovirus antigen immediately prior to vaccination, then daily for 14 days with 3 tests designed for detection of canine parvovirus. Serum anti-FPV antibody titers were determined by use of hemagglutination inhibition prior to vaccination and 14 days later. RESULTS: All fecal parvovirus test results were negative prior to vaccination. After vaccination, 1 kitten had positive test results with test 1, 4 kittens had positive results with test 2, and 13 kittens had positive results with test 3. Only 1 kitten had positive results with all 3 tests, and only 2 of those tests were subjectively considered to have strongly positive results. At 14 days after vaccination, 31% of kittens receiving inactivated vaccines had protective FPV titers, whereas 85% of kittens receiving MLV vaccines had protective titers. CONCLUSIONS AND CLINICAL RELEVANCE: Animal shelter veterinarians should select fecal tests for parvovirus detection that have high sensitivity for FPV and low frequency of vaccine-related test interference. Positive parvovirus test results should be interpreted in light of clinical signs, vaccination history, and results of confirmatory testing. Despite the possibility of test interference, the benefit provided by universal MLV FPV vaccination of cats in high-risk environments such as shelters outweighs the impact on diagnostic test accuracy. 相似文献
70.
Kaplan Hülya Ratering Stefan Hanauer Thomas Felix-Henningsen Peter Schnell Sylvia 《Biology and Fertility of Soils》2014,50(5):735-744
Biology and Fertility of Soils - Agriculturally used soils (Kastanozems) of experimental fields in the Mashavera Valley in southeast Georgia show various degrees of trace metal contamination (Cd,... 相似文献