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231.
Koldo Osoro Rafael Celaya Javier Moreno-Gonzalo Luis M.M. Ferreira Urcesino García Pilar Frutos Luis M. Ortega-Mora Ignacio Ferre 《Strength and Conditioning Journal》2009,62(2):127-135
The aim of this study, performed on 62 adult dry cashmere goats grazing upland perennial ryegrass–white clover pastures and naturally infected with gastrointestinal nematodes, was to investigate the effects of stocking rate (SR: 24 vs. 38 goats · ha-1) and tannin-containing heather supplementation (H: Calluna vulgaris [L.] Hull, Erica spp.) vs. nonsupplementation on parasite burden, fecal egg counts (FEC), and live weight (LW) changes. Goats were randomly assigned to four treatments in a 2 × 2 factorial arrangement and grazed continuously from May to October. Six goats per treatment were slaughtered at the end of the grazing period, and adult worms in the abomasum and small and large intestines of each animal were recovered, counted, and identified. FEC was affected by SR (P < 0.01) but not by H. However, the SR × H interaction was significant (P < 0.05). FEC increased (P < 0.001) along the grazing season in all treatments, and the SR × time interaction was significant (P < 0.001). In general, mean total worm counts in abomasum and small intestine tended to be higher under high SR, although the differences were only significant (P < 0.01) in Trichostrongylus spp. counts. In goats managed under the high SR, the mean of total Teladorsagia circumcincta counts was lower (P < 0.01) in supplemented animals, but no differences were recorded for Trichostrongylus spp., Chabertia ovina, Oesophagostomum columbianum, and Trichuris ovis. The goats gained more LW (P < 0.001) under low SR and when they were heather-supplemented. No significant SR × H interaction was found for LW change. In conclusion, high stocking rate increases the infectivity risk of pasture and the supplementation of grazing goats with heather contributing to improve animals' performance. Notwithstanding, the effect of heather availability on nematode FEC reduction could be highly dependent on the climatic conditions. 相似文献
232.
Fidel Blanco‐Macías Rafael Magallanes‐Quintanar Ricardo D. Valdez‐Cepeda Rigoberto Vázquez‐Alvarado Emilio Olivares‐Sáenz Erasmo Gutiérrez‐Ornelas Juan A. Vidales‐Contreras Bernardo Murillo‐Amador 《植物养料与土壤学杂志》2010,173(6):927-934
Optimum concentrations and/or sufficiency ranges of nutrients are useful for a correct diagnosis and improvement of nutrient status of cultivated plants. To develop boundary‐line approach (BLA) standards for Opuntia ficus‐indica L., a database of N, P, K, Ca, and Mg concentrations in 1‐year‐old cladodes and cladodes fresh‐matter yield was used. The BLA optimum concentrations (associated with estimated maximum yield) for O. ficus‐indica were: N = 13.1 g kg–1, P = 3.2 g kg–1, K = 44.4 g kg–1, Ca = 38.1 g kg–1, and Mg = 17.3 g kg–1. The BLA sufficiency ranges at 95% yield were 8.4–20.3 g kg–1 for N, 2.4–4.2 g kg–1 for P, 38.2–50.8 g kg–1 K, 31.8–45.2 g kg–1 for Ca, and 14.3–20.9 g kg–1 for Mg. The BLA standards are comparable to those obtained in a previous study using compositional‐nutrient‐diagnosis (CND) approach. 相似文献
233.
Sandro R. Urban Albertina X. R. Corrêa Carlos A. F. Schettini Paulo R. Schwingel Rafael M. Sperb Claudemir M. Radetski 《Journal of Soils and Sediments》2010,10(1):65-76
Purpose
Most of the information concerning the effects of contaminated sediments on estuarine organisms deals with the impacts of bed forming sediments. The ecotoxicological potential at the time of a dredging operation is more difficult to assess, and few studies have dealt specifically with resuspended contaminated sediments. The aim of this study was to determine whether release of contaminants through sediment resuspension during a dredging operation in the Itajaí-açu estuary (Brazil) changed the water quality classification and had an ecotoxicological impact on the near-field water column during the critical moment of this operation.Materials and methods
Waters from two sites (control and dredged sites) were analyzed for physicochemical parameters before, during, and after a dredging operation. In parallel, a short-term, sensitive battery of biotests (bacteria, algae, and daphnids) was performed with water samples before and during this operation according to the ISO bioassay protocols.Results and discussion
No short-term toxicity was observed with waters collected before or during the dredging operation. The results showed that desorption of contaminants from suspended particles of sediments with a low level of contamination during a dredging operation lowered the water quality in the near-field water column but that this did not promote significant acute toxicity effects on the organisms tested.Conclusions
More detailed studies are needed (e.g., the question of the reliability of biotests under turbulent, particle-rich conditions) to fully understand this complex issue regarding water column ecotoxicity during the whole dredging operation and to support decisions on the management of dredging activities.234.
Raquel Yvonne Arantes Baccarin Marco Antonio Pereira Neimar Vanderlei Roncati Rafael Ramalho Corso Bergamaschi Stefano Carlo Filippo Hagen 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(10):1079-1084
This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the “age of no return” is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions in both joints of Lusitano foals up to 12 months of age. 相似文献
235.
236.
Porcine respiratory and reproductive syndrome virus (PRRSV) disease, one of the most economically significant viral diseases in the swine industry, is characterized by miscarriages, premature farrowing, stillborn pigs, and respiratory disease associated with death and chronic poor performance of nursing and weaned pigs. Interleukin-12 (IL-12) is a key component in driving the development of cell-mediated immunity as well as stimulating interferon-gamma (IFN-gamma) production from T cells and natural killer cells. Although some studies have investigated the use of IL-12 as a vaccine adjuvant in swine, little is known about its effectiveness as a treatment against viral diseases in swine. The present study investigated whether recombinant porcine IL-12 (rpIL-12) enhances the immune response and thereby diminishes the effects of PRRSV infection in young pigs. Interestingly, in vitro experiments demonstrated that rpIL-12 is capable of inducing swine pulmonary alveolar macrophages (PAMs), the target cells of PRRSV, to produce IFN-gamma in a dose and time dependent manner. In addition, in vitro studies also revealed that rpIL-12 treatment was capable of significantly reducing PRRSV viral titers in PAMs. In vivo administration of rpIL-12 significantly decreased PRRSV titers in the lungs and blood of infected animals. Furthermore, treatment with rpIL-12 prevented significant growth retardation in PRRSV-infected animals. Finally, in response to viral antigen recall challenge, PAMs isolated from rpIL-12-treated/PRRSV-infected animals produced greater amounts of IFN-gamma and lesser amounts of interleukin-10 than PAMs isolated from non-rpIL-12-treated/PRRSV-infected animals. Taken together our data indicate that treatment with rpIL-12 may provide an effective approach to control or ameliorate PRRSV-induced disease in swine. 相似文献
237.
Friton GM Cajal C Ramirez Romero R Kleemann R 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(7-8):304-309
The clinical efficacy of two non-steroidal anti-inflammatory drugs (NSAIDs), meloxicam (Metacam 20 mg/ml) and flunixin meglumine (Finadyne), as adjuncts to antibacterial therapy in the treatment of acute febrile respiratory disease in cattle was compared. The randomised blind, positive controlled study was conducted under feedlot conditions in Mexico. Overall, 201 female cattle (weighing 220-250 kg) diagnosed with bronchopneumonia at the feedlot were recruited into the study. On Day 0 all animals were treated with 20 mg oxytetracycline/kg body-weight (Bivatop 200) by subcutaneous injection, in conjunction with either meloxicam (0.5 mg/kg subcutaneously, Metacam 20 mg/ml, n = 100), or flunixin meglumine (2.2 mg/kg intravenously, Finadyne, n = 101). According to label instructions, meloxicam was administered as a single dose, whereas flunixin meglumine could be administered daily for up to 3 consecutive days depending on the rectal temperature (with re-administration, if rectal temperature > or = 40.0 degrees C). Rectal temperature, respiratory rate, appetite, dyspnoea, coughing, nasal discharge and general condition were recorded on Days 0 (prior to treatment), 1, 2, 3 and 7 using a weighted numerical score. Scores were summed to generate a 'Clinical Sum Score' (CSS, range 7 to 24 points). Individual animal body weights were measured on Days 0 and 7. Nasal swabs were collected from 10 animals per treatment group on Day 0 for microbiological culture. Clinical parameters and the mean CSS showed no significant differences between treatment groups with mean CSS on Days 0 and 7 of 16.18 and 10.55 in the meloxicam group and 16.41 and 10.88 in the flunixin meglumine group. However, a significantly lower mean rectal temperature was measured in the meloxicam group on Day 2 (p < or = 0.01). No significant differences in mean body weights were found between groups. Repeated administration of flunixin meglumine was performed in 45% of the animals. No suspected adverse drug events related to treatments were reported. It is concluded that a single subcutaneous dose of meloxicam was as clinically effective as up to 3 consecutive daily intravenous doses of flunixin meglumine when used as an adjunctive therapy to antibacterial therapy in the treatment of acute febrile respiratory disease in feedlot cattle. 相似文献
238.
Quesada-Pascual F Jimenez-Flores R Flores-Langarica A Silva-Sanchez A Calderon-Amador J Mendez-Cruz R Limon-Flores AY Estrada-Parra S Santos-Argumedo L Estrada-Garcia I Flores-Romo L 《Veterinary immunology and immunopathology》2008,124(3-4):220-229
Armadillos are apparently important reservoirs of Mycobacterium leprae and an animal model for human leprosy, whose immune system has been poorly studied. We aimed at characterizing the armadillo's langerhans cells (LC) using epidermal sheets instead of tissue sections, since the latter restrict analysis only to cut-traversed cells. Epidermal sheets by providing an en face view, are particularly convenient to evaluate dendritic morphology (cells are complete), spatial distribution (regular vs. clustered), and frequency (cell number/tissue area). Lack of anti-armadillo antibodies was overcome using LC-restricted ATPase staining, allowing assessment of cell frequency, cell size, and dendrites extension. Average LC frequency in four animals was 528 LC/mm(2), showing a rather uniform non-clustered distribution, which increased towards the animal's head, while cell size increased towards the tail; without overt differences between sexes. The screening of antibodies to human DC (MHC-II, CD 1a, langerin, CD86) in armadillo epidermal sheets, revealed positive cells with prominent dendritic morphology only with MHC-II and CD86. This allowed us to test DC mobilization from epidermis into dermis under topical oxazolone stimulation, a finding that was corroborated using whole skin conventional sections. We hope that the characterization of armadillo's LC will incite studies of leprosy and immunity in this animal model. 相似文献
239.
Feather content of porphyrins in Eurasian eagle owl (Bubo bubo) fledglings depends on body condition and breeding site quality
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Ismael GALVÁN María del Mar DELGADO Pablo R. CAMARERO Rafael MATEO Rui LOURENÇO Vincenzo PENTERIANI 《Integrative zoology》2018,13(5):569-578
Porphyrins are pigments produced in most animal cells during the synthesis of heme, but their importance for external coloration is unclear. Owls (Order Strigiformes) are among the few animals that accumulate porphyrins in the integument, where it could serve as a means of signaling. Here we hypothesized that the porphyrin content of feathers may depend on body condition and breeding site quality in Eurasian eagle owl (Bubo bubo) fledglings and, thus, constitute amplifiers of the quality of the area where they are born. Using high‐performance liquid chromatography, we found 2 porphyrins (protoporphyrin IX and coproporphyrin III) in the body feathers of 19 eagle owl fledglings from 7 breeding territories. Coproporphyrin III, but not protoporphyrin IX feather concentration, was positively associated with the body mass of fledglings and with the quality of the breeding sites where they were reared with respect to food quality and availability. As coproporphyrin III is produced under oxidative stress, we suggest that good breeding sites may lead to fledglings in good condition. This, in turn, may make fledglings induce a certain level of free radical and coproporphyrin III production to signal to conspecifics their site‐mediated capacity to cope with oxidative stress. This is the first time that porphyrin content in the integument has been found to be related to individual quality, opening a new scenario for studying evolution of animal coloration. 相似文献
240.
Rafael Carrasco-Reinado María Bermudez-Sauco Almudena Escobar-Nio Jesús M. Cantoral Francisco Javier Fernndez-Acero 《Marine drugs》2022,20(1)
Most of the marine ecosystems on our planet are still unknown. Among these ecosystems, microalgae act as a baseline due to their role as primary producers. The estimated millions of species of these microorganisms represent an almost infinite source of potentially active biocomponents offering unlimited biotechnology applications. This review considers current research in microalgae using the “omics” approach, which today is probably the most important biotechnology tool. These techniques enable us to obtain a large volume of data from a single experiment. The specific focus of this review is proteomics as a technique capable of generating a large volume of interesting information in a single proteomics assay, and particularly the concept of applied proteomics. As an example, this concept has been applied to the study of Nannochloropsis gaditana, in which proteomics data generated are transformed into information of high commercial value by identifying proteins with direct applications in the biomedical and agri-food fields, such as the protein designated UCA01 which presents antitumor activity, obtained from N. gaditana. 相似文献