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排序方式: 共有792条查询结果,搜索用时 15 毫秒
621.
Magorzata Brzeziska Yakov Kuzyakov Teresa Wodarczyk Karl Stahr Witold Stpniewski 《植物养料与土壤学杂志》1998,161(6):697-698
It was found that during a 4-day incubation of a Mollic Gleysol with 352 μl 1?1 methane in the headspace, the rate of methane consumption declined exponentially from an initial value of 9.13 μmol kg?1 hour?1 (about 5% of total CO2 evolved) according to first-order kinetics. The increase of dehydrogenase activity due to methane amendment did not exceed 15% of the control value and reached the maximum after two days of incubation. 相似文献
622.
Cristina Fernández José A. Vega Salvador Bará Carmen Beloso Margarita Alonso Teresa Fonturbel 《Annals of Forest Science》2009,66(8):807-807
623.
Paolo Sartor Pierluigi Carbonara Sandro Cerasi Giuseppe Lembo Maria Teresa Facchini Alessandro Lucchetti Rosaria Felicita Sabatella Claudia Musumeci Walter Zupa Maria Teresa Spedicato 《Fisheries Management and Ecology》2019,26(6):661-673
Small‐scale driftnets (SSDs) have been historically used in the Mediterranean without major environmental concern. The introduction of large‐scale driftnets caused unwanted catches of protected species. Specific regulations were therefore issued in European waters, culminating in a proposed moratorium on SSDs. This study aimed to characterise the SSD fishery targeting anchovy (menaide), evaluating its environmental sustainability, economic performance and social relevance. In 2013, a survey by interviews, logbooks and observers on board assessed the order of magnitude of this fishery in terms of fishing capacity and activity, volume of landings and revenues. The menaide fleet consisted in 60 vessels <12 m overall length, moored in little harbours in southern Italy. These nets are highly selective: the target species, European anchovy, Engraulis encrasicholus (L.) and sardine, Sardina pilchardus (Walbaum), dominates the catches, while discards are negligible. The anchovies caught are of high quality and large size; the high prices support fish processing by local factories. Moreover, the results of a SWOT analysis demonstrated that replacing SSDs with a semi‐industrial fishery, like purse seining, would increase impacts on the ecosystem, and a loss of socio‐economic opportunities for several coastal villages. These findings support the option of keeping SSDs operating, in the framework of specifically oriented management measures. 相似文献
624.
Magorzata Rzepkowska Marek ukasz Roszko Magdalena Fajkowska Dobrochna Adamek‐Urbaska Teresa Ostaszewska 《Aquaculture Nutrition》2020,26(3):866-875
A common global trend in modern aquaculture is to reduce or replace fishmeal in fish diets with alternative protein sources, mainly from protein‐rich plants such as soybean; however, plant‐based aquafeeds are a source of substantial amounts of phytoestrogens. Phytoestrogens belong to endocrine‐disrupting chemicals (EDCs) which can negatively interfere with fish reproduction; thus, they should be avoided in sturgeon diet. Therefore, the aim of the study was to evaluate concentrations and the profile of dietary isoflavone phytoestrogens in the two commercial sturgeon diets. A substantial amount of isoflavones, reaching in total from 1.5 to 50 mg/kg of feed, were found in analysed diets. Genistein and daidzein, which are typical constituents of soybean, were the most abundant phytoestrogens in the analysed feeds. Equol, the third most abundant phytoestrogen in the tested samples, was originated most probably from animal components. Additionally, the accumulation of dietary isoflavones in the liver, blood and gonads of two commonly farmed sturgeon species (Acipenser gueldenstaedtii and Acipenser baerii) after long‐term dietary exposure was also assessed. Significant concentrations of isoflavones were found in liver and blood samples of both sturgeon species at 600th and 800th dph, indicating high accumulation of these compounds, which may lead to endocrine disturbance. 相似文献
625.
The objective of this study was to evaluate the effect of probiotics as digestive system maturation promoters in larvae of the California halibut, Paralichthys californicus, during ontogeny. Three commercial probiotics: Levucell®, Bactocell®, and live yeast, were supplied at a concentration of 50 mg/L, using enriched rotifers and Artemia nauplii as vectors. Total and specific activities of trypsin, leucine‐aminopeptidase (LAP), lipase, chymotrypsin, and pepsin were assessed throughout the development. Growth in terms of length was not significantly different between treatments. Total pepsin and chymotrypsin activity were significantly higher at the end of the experiment, 46‐d posthatch (dph) in larvae supplied with Bactocell. However, no significant effect of the probiotic was detected for trypsin, lipase, and LAP. On the basis of the results, California halibut larvae seemed to have adequate alkaline proteolytic activity early in development, whereas acid proteolytic activity was not detected until the complete formation of a functional stomach. The feeding protocol and probiotics evaluated were unable to improve the morphological development of digestive system or the digestive enzyme activity early on. Nevertheless, the increase in activity of pepsin and chymotrypsin observed at 46 dph suggests a potential use of these probiotics once the metamorphosis is completed, and thus warrants further evaluation. 相似文献
626.
Susana Carvalho Manuela Falcão João Cúrdia Ana Moura Dalila Serpa Miguel B. Gaspar Maria Teresa Dinis Pedro Pousão-Ferreira Luís Cancela da Fonseca 《Aquaculture International》2009,17(6):571-587
The present work aims to assess the importance of settlement ponds (SP) in semi-intensive fish farms by studying benthic dynamics
in an aquaculture fish farm, more specifically in the water reservoir (WR) and SP and also in production (P) and nonproduction
(C) ponds during a 16-month period. In Portugal, a SP is only mandatory for intensive fish farms, and another objective of
the present study is to assess the importance of these areas in semi-intensive fish farms. The WR was the area with highest
diversity and evenness, as well as the higher number of exclusive taxa and taxa sensitive to organic enrichment. P and SP
samples showed signs of higher disturbance levels, emphasized namely by the association of the opportunistic annelids Capitella spp. and Tubificidae. However, the benthic data from SP points to lower disturbance levels than P both due to an increase
in the percentage of sensitive taxa observed in June and October 2004 and by the association of this latter sample with water
reservoir samples as evidenced by canonical correspondence analysis. Moreover, a higher and increasing number of taxa when
compared with the P area were also observed. Therefore, in semi-intensive fish farms, where effluents from P ponds are directly
discharged to the lagoon, the potential environmental impacts would be more severe. In conclusion, the imposition of SP in
semi-intensive fish farms should be considered, especially because most fish farms are located within relevant wetland areas. 相似文献
627.
Teresa Ostaszewska Konrad Dabrowski Karolina Kwasek Tiziano Verri Maciej Kamaszewski Jerzy Sliwinski Lukasz Napora‐Rutkowski 《Aquaculture Research》2011,42(12):1796-1806
The aim of the present study was to evaluate the effects of three formulated diets: wheat gluten protein‐based diets supplemented with Lys–Gly dipeptide (PP) or free lisine and glycine (AA), and a control diet without lysine supplementation (CON), two commercial starters: Aller Futura (AF), Aglo Norse (AN) and frozen Chironomidae larvae (CH) for on the growth and digestive system development of rainbow trout. The experiment lasted 28 days and survival at the end of the experiment was the highest in the group fed AF (87.9±4.2%) and the lowest in the group fed the CON diet (74.0±4.3%). Fish fed the CON diet showed a significantly lower crude protein content, and the AA group had a significantly higher lipid level (P≤0.05) in body carcass compared with the other groups. The highest density of intestinal goblet cells (P≤0.05) was observed in fish fed the CON diet, while the lowest density was seen in the distal intestine in the AF group. The hepatocyte cytoplasm of all fish stored more glycogen than lipids. These results indicate that wheat gluten protein‐based diets supplemented with dipeptide Lys–Gly (PP) or free lysine and glycine (AA) supported growth, protein efficiency rate and intestine epithelium homeostasis. On the other hand, fish fed CON (lysine‐deficient diet) showed lower survival and growth rate, and disturbances of intestine epithelium homeostasis, probably as a result of lysine deficiency. 相似文献
628.
Production of diatom–bacteria biofilm isolated from Seriola lalandi cultures for aquaculture application 下载免费PDF全文
Controlled incorporation of selected microalgae and bacteria in aquaculture systems can be beneficial because they can act as microbiological control. That is why the characteristics of biofilm generated naturally in Seriola lalandi culture cages were analysed, their potential benefit to the growth of larvae was studied, and their controlled use for improving the larval viability and as a vector to improve incorporation of previously studied probiotic bacteria was tested. According to biodiversity results, these biofilms are composed of a diatom–bacteria mix showing a decrease in biodiversity in laboratory culture conditions being dominated by Navicula phyllepta and bacteria of the family Rhodobacteraceae. This can be produced on mesh substrates incorporated in bioreactors with rapid growth rate and adhesiveness. Preliminary results from the addition of substrates with this specific biofilm in larvae culture systems showed that it is consumed by the larvae without negative effects, while positive effects on the viability of larvae in combination with probiotics were observed. Considering preliminary results, the addition of these specific substrates with diatom–bacteria biofilms could be a good improvement for aquaculture systems and together with the use of probiotics can contribute to maintaining a stable and controlled system improving the viability of the larval fish culture in its early stages. 相似文献
629.
Margarita Gonzlez-Martín Vanessa Silva Patricia Poeta Juan Alberto Corbera María Teresa Tejedor-Junco 《The Veterinary quarterly》2022,42(1):1
Osteomyelitis is a challenging infectious disease affecting humans and animals. It is difficult to diagnose because, in many cases, symptoms are non-specific and, for example in implant-related cases, can appear long time after surgery. In addition to this, it is also difficult to treat due to the need to find the appropriate antibiotic regime and delivery system to reach the site of infection and to avoid development of bacterial resistance. The central purpose of this review is to compare the microbiological aspects of osteomyelitis in human and veterinary medicine, with the aim of improving the microbiological diagnosis and treatment of this infection in animals. Furthermore, the study of osteomyelitis in animals may help to improve the development of animal models for testing new treatments in humans. Host factors and underlying conditions have been studied mainly in humans, although aspects as immunodeficiency have been described in some veterinary cases. Even when Staphylococcus aureus is still considered the most prevalent causing microorganism, this prevalence should be reviewed using molecular diagnostic techniques, and this could affect treatment options. New approaches to treatment include local delivery of antibiotics using different biomaterials, antimicrobial photodynamic therapy, and new antimicrobial compounds. We would like to remark the need of large, high-quality clinical trials and of the development of guides for the diagnosis and treatment of osteomyelitis in different animal species. 相似文献
630.
Diego Iribarren Paula Dagá María Teresa Moreira Gumersindo Feijoo 《Aquaculture International》2012,20(4):779-789
Probiotics are a live microbial feed supplement that beneficially affects the host animal. As aquaculture is one of the main areas where probiotics can be applied, the environmental suitability of using probiotics in hatching and nursing facilities for turbot farming was evaluated through the life cycle assessment (LCA) methodology. This LCA study showed that the potential environmental impacts associated with probiotic production are generally offset by the impact reductions linked to lower consumption levels and reduced waste and emission generation rates within the hatching and nursing subsystem. Thus, the use of probiotics is recommended in order to enhance the performance of turbot aquaculture systems provided that operational and economic advantages are attained. 相似文献