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51.
Miranda JP Nascimento EM Cruz HJ Yin H Zweygarth E Oliva AG 《American journal of veterinary research》2006,67(11):1908-1913
OBJECTIVE: To establish optimal conditions for long-term culture of the erythrocytic stage of Theileria uilenbergi. SAMPLE POPULATION: Red blood cells from 3 splenectomized sheep experimentally infected with a blood stabilate of T uilenbergi. PROCEDURES: Cultures of T uilenbergi were initiated by use of blood from experimentally infected sheep collected when parasites were detected in Giemsa-stained thin blood smears. Different culture conditions were tested to optimize in vitro growth of the organisms. Subcultures were performed at a ratio of 1:2, 1:4, and 1:8 when the percentage of parasitized erythrocytes (PPE) was at least 1% or when the initial PPE was doubled. RESULTS: The optimal culture medium was HL-1 medium (a complete chemically defined medium) supplemented with 20% sheep serum and 0.75% chemically defined lipids. Optimal culture conditions included incubation in a humidified 2% O(2), 5% CO(2), and 93% N(2) atmosphere at 37 degrees C. Cultures of the merozoite stage of the parasite were continuously propagated in vitro for > 1 year. The PPE reached values of up to 3%. CONCLUSIONS AND CLINICAL RELEVANCE: Optimization of culture conditions to reach a high PPE seems worthwhile. The continuous propagation of T uilenbergi in culture allows the production of parasite material without infecting animals and provides a continuous laboratory source of parasites for further studies. 相似文献
52.
In perennial ryegrass seed production, the establishment of seed yield potential occurs until the point of anthesis. However, utilizing potential seed yield is predominately focused on processes after anthesis, namely seed set (%) and seed filling. In practice, seed yield is the product of the number of harvested seeds remaining after cleaning and average seed weight. For this study, the anthesis patterns and seed set were recorded in a diploid variety grown in seed production fields in three different Danish regions with contrasting weather conditions and investigated in 2013 and 2014. Increases in the total precipitation during anthesis reduced the anthesis synchrony and the seed set, which ranged from 50% to 66%. Under semi‐controlled environmental conditions in which the influence of precipitation was excluded, the seed set was found to be influenced by the floret position in the spikelet and ranged from 73% in the florets in basal positions to 25% in the distal florets. It is suggested that a lower number of florets per spikelet will reduce the anthesis period. These results may provide insights for breeding programmes focused on increasing seed yield. 相似文献
53.
João Carvalho Óscar Cardoso Mário Costa Abel Rodrigues 《European Journal of Forest Research》2017,136(1):185-192
This work presents the results of a study on the variation of the chemical composition of Pyrenean oak (Quercus pyrenaica Willd.) heartwood among different sites and its relationship with the soil chemical characteristics. The chemical characteristics of the heartwood are quantified in terms of proximate and ultimate analysis, calorific value and ash composition. Subsequently, the relationship between the wood chemical characteristics and the soil characteristics was also examined. The results showed no significant differences between the wood chemical characteristics from different sites. There are, however, significant differences between trees from the same site regarding the wood ash content, the calorific value and the contents of nitrogen and hydrogen. Strong correlations were observed between the heartwood ash contents of BaO, MnO, CuO and TiO2 and the soil nitrogen, phosphorous and potassium and the soil exchangeable base contents. 相似文献
54.
Marie Fiers Catherine Chatot Véronique Edel-Hermann Yves Le Hingrat Abel Yanougo Konate Nadine Gautheron Emmanuel Guillery Claude Alabouvette Christian Steinberg 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):353-371
Skin blemishes of potato (Solanum tuberosum L.) tubers can cause severe economical losses to production. Some blemishes are due to known pathogens and others whose causes
are unknown are called atypical blemishes. The present work aims at determining the origin of superficial atypical blemishes
on a set of 204 tubers coming from 12 different French regions producing potato. The diversity of fungi and Streptomyces bacteria associated with blemishes was investigated by systematic isolation followed by identification by sequencing the
internal transcribed spacer of the ribosomal DNA for fungi and by sequencing the 16S ribosomal DNA for bacteria. We found
a high microbial diversity represented by 349 fungal isolates belonging to at least 47 different species and 21 bacterial
strains of Streptomyces sp. The most represented fungi belonged to the genera Fusarium, Rhizoctonia, Alternaria, Penicillium, and Clonostachys. The pathogenicity of representative isolates was assessed in three bioassays; two bioassays based on single inoculations
in previously sterilized potting mixture, and one bioassay based on both single and double inoculations under hydroponic conditions.
We fulfilled the Koch’s postulates for Rhizoctonia solani AG 3 producing sclerotia. For other fungal and bacterial strains, our results did not show any causality or relationship
between a single isolate or a complex and the occurrence of the blemishes. Moreover, the observation of irregular polygonal
sunken corky lesions (polygonal lesions)—the most frequent atypical blemish—on non-inoculated tubers, suggested that the atypical
blemishes could as well be a reaction of the plant to stressful environmental conditions. 相似文献
55.
We present the first reported study of Pearl millet (Pennisetum typhoides) goitrogenesis and enterohepatonephropathy in 5-9-month-old Nubian goats of either sex. The goats were fed 0.25 or 1 g millet per kg body weight per day for 62 days. The effects on thyroid follicles, intestines, liver and kidneys are described and correlated with clinical signs, changes in serum and tissue iodine and selenium concentrations and alterations in serum aspartate transaminase, gamma glutamyl transferase, total protein, total lipids and other constituents and haematological values. 相似文献
56.
57.
Chol D. T. Abel Saroj K. Sharma Yona N. Malolo Sung Kyu Maeng Maria D. Kennedy Gary L. Amy 《Water, air, and soil pollution》2012,223(8):5205-5220
Soil aquifer treatment (SAT) is a cost-effective natural wastewater treatment and reuse technology. It is an environmentally friendly technology that does not require chemical usage and is applicable to both developing and developed countries. However, the presence of organic matter, nutrients, and pathogens poses a major health threat to the population exposed to partially treated wastewater or reclaimed water through SAT. Laboratory-based soil column and batch experiments simulating SAT were conducted to examine the influence of temperature variation and oxidation?Creduction (redox) conditions on removal of bulk organic matter, nutrients, and indicator microorganisms using primary effluent. While an average dissolved organic carbon (DOC) removal of 17.7?% was achieved in soil columns at 5?°C, removal at higher temperatures increased by 10?% increments with increase in temperature by 5?°C over the range of 15 to 25?°C. Furthermore, soil column and batch experiments conducted under different redox conditions revealed higher DOC removal in aerobic (oxic) experiments compared to anoxic experiments. Aerobic soil columns exhibited DOC removal 15?% higher than that achieved in the anoxic columns, while aerobic batch showed DOC removal 7.8?% higher than the corresponding anoxic batch experiments. Ammonium-nitrogen removal greater than 99?% was observed at 20 and 25?°C, while 89.7?% was removed at 15?°C, but the removal substantially decreased to 8.8?% at 5?°C. While ammonium-nitrogen was attenuated by 99.9?% in aerobic batch reactors carried out at room temperature, anoxic experiments under similar conditions revealed 12.1?% ammonium-nitrogen reduction, corresponding to increase in nitrate-nitrogen and decrease in sulfate concentration. 相似文献
58.
Ghislain Moussavou Dong Hoon Kwak Brice Wilfried Obiang-Obonou Cyr Abel Ogandaga Maranguy Sylvatrie-Danne Dinzouna-Boutamba Dae Hoon Lee Ordelia Gwenaelle Manvoudou Pissibanganga Kisung Ko Jae In Seo Young Kug Choo 《Marine drugs》2014,12(9):4898-4911
Seafoods and seaweeds represent some of the most important reservoirs of new therapeutic compounds for humans. Seaweed has been shown to have several biological activities, including anticancer activity. This review focuses on colorectal and breast cancers, which are major causes of cancer-related mortality in men and women. It also describes various compounds extracted from a range of seaweeds that have been shown to eradicate or slow the progression of cancer. Fucoidan extracted from the brown algae Fucus spp. has shown activity against both colorectal and breast cancers. Furthermore, we review the mechanisms through which these compounds can induce apoptosis in vitro and in vivo. By considering the ability of compounds present in seaweeds to act against colorectal and breast cancers, this review highlights the potential use of seaweeds as anticancer agents. 相似文献
59.
Occurrence and recurrence of gastric dilatation with or without volvulus after incisional gastropexy
John F. Przywara Steven B. Abel John T. Peacock Susan Shott 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(10):981-984
This study investigated recurrence of gastric dilatation without (GD) or with volvulus (GDV) after incisional gastropexy (IG) in dogs that underwent IG for prevention of GDV. Signalment, concurrent surgical procedures, presence of GD or GDV at the time of IG were obtained from medical records of dogs that underwent IG. Owners were contacted to determine whether the dogs experienced GD or GDV after IG, dates of postoperative GD or GDV episodes, survival status, date of death for deceased dogs. Gastric dilatation and GDV recurrence rates were calculated for 40 dogs that had at least 2 y follow-up from the time when IG was performed and for dogs that experienced GD or GDV during the follow-up period. No dogs experienced GDV after IG and 2 dogs (5.0%) experienced GD after IG. The results suggest that GD and GDV rates after IG may be comparable to recurrence rates after other methods of gastropexy. 相似文献
60.