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121.
Establishing grazing and grazing-excluded patches increases plant and invertebrate diversity in a Mediterranean oak woodland 总被引:1,自引:0,他引:1
Miguel N. Bugalho Xavier Lecomte Merícia GonçalvesMaria C. Caldeira Manuela Branco 《Forest Ecology and Management》2011,261(11):2133-2139
Grazing is a global, dominant land use affecting biodiversity and ecosystem processes. In Mediterranean ecosystems grazing is a major ecological and evolutionary driver but, surprisingly, there is little information on the use of grazing as a tool to manage biodiversity in these ecosystems. We conducted an experiment to assess if establishing grazing and small scale grazing-excluded areas would increase plant and invertebrate diversity in a Mediterranean evergreen oak woodland. Plant community traits were different between treatments. Biomass of herbs (176.7 ± 18.3 g m−2vs 100.4 ± 10.6 g m−2) and litter (291.0 ± 38.3 g m−2vs 186.8 ± 26.4 g m−2), as well as the total cover of legumes (0.83 ± 0.05 vs 0.91 ± 0.03) were higher, and the proportion of bare ground (0.83 ± 0.05 vs 0.91 ± 0.03) was lower, in ungrazed plots. There were no differences in the number of plant species between treatments. Some plant species and invertebrate taxa were recorded exclusively in grazed or ungrazed plots. Invertebrate detritivores and sap sucking insects were more abundant in ungrazed plots. Ant assemblages were functionally different between treatments: Honeydew-gatherer ants were associated with ungrazed and higher plant biomass plots, and seed-eaters as well as aggressive predator ant species were associated with grazed, open habitat, plots. Management practices that maintain grazing and small scale grazing-excluded areas can increase habitat heterogeneity and promote herbaceous plant and invertebrate diversity at the local level. 相似文献
122.
Santos RL Almeida AP Xavier MN Paixão TA Wilson RP Dandekar S Raffatellu M Bäumler AJ 《Veterinary pathology》2011,48(5):933-941
The goal of this study was to morphologically characterize a ligated ileal loop model of Salmonella enterica serotype Typhimurium infection in rhesus macaques (Macaca mulatta) and to verify the occurrence of Salmonella-induced cell death in vivo. Eight adult healthy male rhesus macaques were used for ligated ileal loop surgery. Four macaques had been intravenously inoculated with simian immunodeficiency virus (SIV) mac251. Ileal ligated loops were inoculated with wild-type (WT) S. Typhimurium strain IR715 (ATCC14028 nal (r)), an isogenic noninvasive mutant strain (ATCC14028 nal (r) ΔsipAΔsopABDE2), or sterile Luria Bertani broth. Loops were surgically removed at 2, 5, and 8 hours post-inoculation (hpi). Intestinal samples were processed for histopathology, immunohistochemistry for detecting Salmonella, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and transmission electron microscopy. Combined histopathology scores were similar between SIV-infected and control macaques. As expected, the invasion-deficient mutant was less pathogenic than WT S. Typhimurium. Neutrophil infiltrate in the intestinal mucosa correlated with bacterial loads (r = 0.7148; P < .0001) and fluid accumulation (r = 0.6019; P < .0001) in the lumen of the intestinal loops. Immunolabeled WT S. Typhimurium was observed in the epithelium and lamina propria at the tip of the villi at 2 hpi, progressing toward deeper lamina propria at 5-8 hpi. Most TUNEL-positive cells localized to the lamina propria, and some had morphological features of macrophages. Ultrastructurally, bacteria were observed intracellularly in the lamina propria as well as within apoptotic bodies. This study provides morphological evidence of Salmonella-induced cell death in vivo in a relevant nonhuman primate model. 相似文献
123.
Guimarães Ade S Gouveia AM do Carmo FB Gouveia GC Silva MX Vieira Lda S Molento MB 《Veterinary parasitology》2011,176(2-3):265-269
Parasitic infection is recognized worldwide as a limiting factor in the production of goats, and various control methods are used to reduce economic losses, often without considering the epidemiology of the parasites. This has led to the development of highly tolerant parasite populations and the presence of chemical residues in the beef and milk. The objective of this study was to determine the level of knowledge of goat farmers about parasitic diseases and to correlate this with the epidemiology of endoparasites and parasite control practices in goat farms in the state of Minas Gerais, Brazil. The analysis was based on a questionnaire applied by trained veterinarians. The sample was homogeneous throughout the state, covering 18.4% (157/853) of municipalities. Eighty-four dairy goat farms in 81 municipalities and 200 properties with beef goats in 76 municipalities were evaluated. The herd size per goat farm ranged from 4 to 57 (average 24) for beef herds and from 2 to 308 (average 63) for dairy farms. The majority of the beef herd production was extensive and semi-extensive (98.5%), while the dairy herds were maintained under intensive farming (98.8%). The mixed production of goats and sheep was reported by 36.5% of beef goat farmers and by 20.2% of dairy goat farmers. Among the beef goats farms on which the technological level was determined, 2.0% were categorized as having high technological level, 34.5% as medium, and 63.5% as low. Of the 84 dairy farms, 30% operated at a high, 47% at a medium, and 23% at a low technological level. The adoption of practices to reduce parasitism, such as the quarantine of animals, treatment of newly arrived animals, regular cleaning of the floor, and technical assistance, was significantly higher on dairy farms than on beef farms. Although 85.7% of dairy farmers and 83% of beef farmers medicate their animals, the treatments were performed without technical criteria, and deworming intervals ranged from 30 to 120 days or more. The average interval between treatments was significantly longer in dairy goat herds (4.8 months) than in the beef herds (3.6 months). The most commonly used drugs were macrocyclic lactones (37.7% in dairy and 39.5% in beef herds) and benzimidazoles (48.9% in dairy and 31.5% in beef herds). Goat production in Minas Gerais is still in its infancy, and even though using a control program associated with other health practices, producers still rely heavily on chemicals to get satisfactory results. 相似文献
124.
Manteca X 《Topics in companion animal medicine》2011,26(1):33-36
With increasing age, some dogs develop a neurogenerative disease that is commonly referred to as canine cognitive dysfunction syndrome (CDS). Diagnosis of CDS can be clinical or based on laboratory tests. The main behavioral changes associated with CDS are disorientation, altered interactions with people or other animals, sleep-wake cycle alterations, house-soiling, and changes in activity level. Ruling out medical conditions that can cause similar changes in behavior is important when performing a clinical diagnosis. Management of CDS includes dietary and pharmacological intervention. Dietary treatment of CDS has been based on the use of antioxidants and mitochondrial cofactors, and recent work has shown that long-term supplementation with medium-chain triglycerides can improve cognitive function in aged dogs. CDS must be considered an animal welfare issue and the implications of this are discussed in this article. 相似文献
125.
Social network analysis has generated a great number of research findings in the organizational and management literature, in which the so‐called territorial clusters have often been represented through the network metaphor. However, while scholars primarily examine the network structure and the internal heterogeneity, we have specifically analyzed the diverse types or roles of informational brokers which firms can perform. We also posit that innovation generated by these firms is moderated by their own capabilities and, more particularly, we analyze how innovation is affected by brokerage roles and the moderating effect of R&D in the Spanish ceramic tile cluster. Our results show that different brokerage roles played by clustered firms have different implications in terms of innovation. Another relevant and related result refers to the interactive effect of brokerage roles and absorptive capacity, which becomes more or less significant depending on the role being played in each case. 相似文献
126.
Bhargavi Priyadarshini Martin Xavier Binaya Bhusan Nayak Tony Apang 《Journal Of Aquatic Food Product Technology》2018,27(5):643-655
Surimi was prepared by washing with single washing cycle with cold water (T-1), alkaline saline (0.2% NaHCO3 and 0.15% NaCl; T-2) solution, and with calcium chloride and salt (0.2% CaCl2 and 0.1% NaCl; T-3), respectively, and compared with conventional washed (CW) surimi. T-2 exhibited significantly (p ≤ 0.05) increased moisture content, which correlated with increased yield, pH and also significantly decreased lipid and ash content. A significant (p ≤ 0.05) decrease in expressible moisture content was also observed in T-2, which suggested higher water holding capacity compared to other treatments. Heat-induced surimi gels exhibited highest L* (p ≤ 0.05), followed by surimi in all the treatments. In the case of L*, T-1 showed highest lightness, followed by T-2, which was comparable to CW. The lowest myoglobin content was exhibited by CW surimi (p ≤ 0.05), which is due to repeated washings. T-2 gel showed higher elasticity, texture, and overall acceptability than others (p ≤ 0.05), except for the whiteness. In all the aspects, T-2 was comparable with CW. Washing with one cycle of T-2 solution can not only improve the quality of surimi but can reduce the wastage of water that is released into the environment without further treatment. 相似文献
127.
Gulnara Balakishiyeva Madat Qurbanov Alamdar Mammadov Shaniyar Bayramov Jalal Aliyev Xavier Foissac 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(4):457-462
‘Candidatus Phytoplasma brasiliense’, a phytoplasma taxon associated with hibiscus witches’ broom disease was first described in 2001
in Brazil. In September 2007, a peach tree (Prunus persica) displaying yellowing symptoms reminiscent of phytoplasma infection was sampled in Guba region of Azerbaijan. A phytoplasma
was detected in the diseased peach tree by nested PCR amplification of its 16S rDNA with universal primers for phytoplasmas.
Phylogenetical analyses of the amplified 16S rDNA showed that the phytoplasma infecting the peach tree corresponded to ‘Ca. P. brasiliense’, a species never reported in Euro-Mediterranean area. To set up a detection assay, cloning of a ‘Ca. P. brasiliense’ DNA fragment was undertaken by comparative RAPD. The amplified dnaK-dnaJ genetic locus was used to design a nested PCR assay able to amplify all ‘Ca. P. brasiliense’ isolates of the subgroup 16SrXV-A without amplifying the related members of the group 16SrII. This assay
also allowed confirming the first detection of ‘Ca. P. brasiliense’ in diseased basil collected in south Lebanon. 相似文献
128.
Stoécio Malta Ferreira Maia Francisco Alisson S. Xavier Teógenes Senna Oliveira Eduardo Sá Mendonça João A. Araújo Filho 《Agroforestry Systems》2007,71(2):127-138
Many environmental benefits have been attributed to agroforestry systems in various ecosystems around the world. However,
there is a limited amount of information to evaluate this agricultural system in the semi-arid region, specifically in the
region of Ceará, Brazil. The objective of this work was to evaluate five agricultural (four agroforestry and one conventional)
systems in order to test the hypothesis that the agroforestry systems promote an increase in the soil organic carbon stocks
and organic carbon pools, thus improving soil quality. The following treatments were tested: agrosilvopasture (AGP), silvopasture
(SILV), traditional agroforestry (TRAG), intensive cropping (IC), and native forest (NF). The soil samples were collected
at four depths: 0–6, 6–12, 12–20 and 20–40 cm. Total soil organic carbon stocks and the organic carbon pools (microbial biomass-C,
mineralizable-C, oxidizable-C, free, occluded light fraction organic matter, and C in the humic substances) were analyzed.
After 5 years of experimental cultivation, the soil under the SILV system presented the best results for the attributes studied,
preserving, and in some cases, improving these attributes, when compared to the other conditions. The traditional agroforestry
system (TRAG) reduced total organic carbon stocks and, consequently, C in some organic matter compartments, indicating that
the fallow period was not sufficient to maintain soil quality. The AGP and IC systems presented significant losses in some
of the soil organic matter (SOM) pools, suggesting that the soil environment had been degraded. The most labile SOM components
were considered sensitive indicators of change in the soil quality. The silvopasture system can, therefore, be recommended
as an alternative soil management strategy for food production and for the maintenance of soil quality and agricultural sustainability
in the semiarid region of Ceará state. 相似文献
129.
Luboya Luboya Wa Malangu Mposhy Kaleka Mwenyi Ngulu Nsasi Nkokele Bimwala Maryabo Kazembe Pourrut Xavier Vincent Tom Gonzalez Jean-Paul 《Tropical animal health and production》2017,49(4):875-878
Tropical Animal Health and Production - Caprine tuberculosis is a major health problem for goats and a major zoonosis of veterinary public health interest. In order to prepare a response to and... 相似文献
130.