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81.
82.
Federico Ferreres Graciliana Lopes Angel Gil-Izquierdo Paula B. Andrade Carla Sousa Teresa Mouga Patrícia Valent?o 《Marine drugs》2012,10(12):2766-2781
Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC50 = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC50 = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC50 = 0.93 mg/mL dry weight), followed by F. spiralis (IC50 = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process. 相似文献
83.
Carla Roncoli Benjamin S. Orlove Merit R. Kabugo Milton M. Waiswa 《Agriculture and Human Values》2011,28(1):123-138
Climate change is confronting African farmers with growing uncertainties. Advances in seasonal climate predictions offer potential
for assisting farmers in dealing with climate risk. Experimental cases of forecast dissemination to African rural communities
suggest that participatory approaches can facilitate understanding and use of uncertain climate information. But few of these
studies integrate critical reflections on participation that have emerged in the last decade which reveal how participatory
approaches can miss social dynamics of power at the community level and in the broader context. Furthermore, neither climate
application research nor theoretical critiques of participation fully examine the culturally constructed nature of participation.
Drawing on sociolinguistic analysis, in-depth interviews, and ethnographic observation, this paper examines how Ugandan farmers
engage in participation in the context of discussions of seasonal climate forecasts. Forecasts were presented to farmers groups
whose members were then asked to discuss the forecast among themselves. In doing so, groups sought to develop a common understanding
of the forecast and consensual plans for response strategies. Focusing on one particular group meeting as an example, we show
how different cultural styles of participation affect the interpretation of the forecast and the formulation of response strategies.
Group interaction is shown to be mostly structured around two styles of participation. On the one hand, there is the “Western”
style advocated by NGOs and the government, which centers on ensuring that all individuals who are present have opportunities
to speak during discussion and to vote on group decisions. On the other hand, a “Kiganda” style of participation emphasizes
the importance of affirming ties to a collectivity, respect for social hierarchy, deployment of good manners, and consensus
building. The case study illuminates how the performance of different styles of participation is grounded in localized frameworks
of language and culture but also draw on political and policy discourses at the national level. Although a cultural high value
on consensus may work in favor of prominent members, the availability of multiple styles of participation also enables group
members to exercise their agency in positive ways. Attention to the interplay of different styles of participation throws
light on the subtle social processes that shape how knowledge is assessed, which sources are trusted, which and whose interpretations
prevail, what options are deemed viable, how costs and benefits are calculated, and whose resources are mobilized in the effort
to reduce vulnerability to climate risk. These are key questions for an assessment of the role of boundary organizations,
such as farmer associations, in the communication and application of climate forecasts in agriculture. 相似文献
84.
Camilla A Santos Bruno C Rossini Carla G Marques Pedro M Galetti Jr Patrícia D Freitas 《Aquaculture Research》2012,43(10):1567-1570
In the present work, EST‐SSR (expressed sequence tag‐simple sequence repeat) loci were obtained by screening 45 000 ESTs from the Pacific white shrimp Litopenaeus vannamei, which was available in a database of the ShEST (Shrimp EST Genome Project) consortium. Fifty‐two of 600 EST‐SSR loci were selected. From this total, 21 EST‐SSRs were polymorphic among 40 individuals and had their gene products ascribed. Two to 20 alleles per locus were detected and the observed heterozygosity ranged from 0.15 to 0.86. Eight loci presented a significant heterozygote deficit after the Bonferroni correction, which was attributed to null alleles. Seven loci were able to have their protein products, molecular functions and biological processes determined. Our results are promising for future studies that relate the levels of these gene polymorphisms with different biological responses to stress in aquaculture. 相似文献
85.
This study evaluated the effect of dietary supplementation with l-tryptophan (L-TRP), a serotonin precursor, on the aggressiveness of juvenile matrinxã Brycon amazonicus. Fish were kept in individual aquaria for 7 days receiving the diets: D1 (control: 0.47% of TRP), D2 (0.94% of TRP), D3 (1.88% of TRP), and D4 (3.76% of TRP). After this, they were grouped with an intruder fish to establish a resident–intruder relationship during periods of 20 min. Blood cortisol, glucose, chloride, sodium and calcium; hemoglobin, hematocrit, red blood cell count and volume; liver glycogen and lipids were measured. Territoriality had significant effect on the aggressiveness of matrinxã (the residents were more aggressive than intruders, P < 0.001) and tryptophan significantly affected their behavior. Fish fed with the D2 diet presented a longer latency until the first attack (P = 0.0069) and bit the intruder fewer times (P = 0.0136) during the period of observation, compared to the control group. The frequency of bites and chases after the first attack was not affected by the dietary supplementation of TRP. Physiological variables were not significantly affected by the diet, except for a moderate increase in cortisol level in fish fed with D2 diet after the fight, indicating slight activation of the hypothalamus–pituitary–interrenal axis. The results show that juvenile matrinxã have aggressive and territorial behavior and that a diet containing 9.4 g TRP kg?1 alter their aggressiveness, without affecting the stress-related physiological parameters. 相似文献
86.
Troncoso IC Cazenave J Bacchetta C Bistoni Mde L 《Fish physiology and biochemistry》2012,38(3):693-702
This study evaluated the histopathological changes in gills and liver of Prochilodus lineatus inhabiting the Salado River basin. Fish were collected in four different sampling stations. The histological lesions in the tissues were examined under light microscopy and evaluated with quantitative analyses. The morphometric analysis of the gills showed a significant shortening of secondary lamellae and a lower percentage of area for gas exchange in fish from station 1 (an urban area, located near the mouth of the Salado River) in comparison with fish gills from the reference site (station 4, a relatively pristine area). Moreover, a significantly higher area occupied with necrotic foci and the occurrence of an important inflammatory response were observed in fish liver of station 1 than the samples caught from other stations. Thus, histopathological evidences showed differences among sites, which could be related to different environmental conditions. 相似文献
87.
88.
Ediófila Brito-Rocha Letícia dos Anjos Ana Cristina Schilling Ândrea Carla Dalmolin Marcelo S. Mielke 《Agroforestry Systems》2017,91(1):9-15
Carpotroche brasiliensis is a dioecious tree species native of the Brazilian Atlantic rainforest. Due to medical and industrial use of the oil extracted from its seeds, C. brasiliensis has a great potential for cultivation as non-timber forest product in agroforestry systems. This study was conducted with the objective to analyze the leaf dimensions of male and female adult trees and seedlings of C. brasiliensis. Two hypotheses were tested: (a) leaf dimensions do not differ between male and female adult genotypes; and (b) it is possible to develop single regression models for predicting leaf area (LA) from dimensional variables encompassing male and female adult genotypes and seedlings. LA, leaf length (L) and maximum leaf width (W) were measured in leaves collected from seven male and seven female adult genotypes and three seedling lots. The feasibility of using a single model for leaves of males and females, and seedlings and adults, was tested by analysis of covariance (ANCOVA). The prediction errors (PE) for each of the regression models were calculated from the cross-validation method. The average values of L, W and LA were, respectively, 136, 142 and 457 % higher in adults than in seedlings, and the average values of leaf shapes (L:W) of seedlings were intermediate between the average values of L:W of adult males and females. The average values of L did not differ between adult males and females, but significant differences were observed between males and females for W, LA and L:W (both p < 0.01, nested ANOVA). The mean L:W values of adult males and females, and seedlings, indicate that leaf shape should be used as a criterion for sex differentiation in this species. It was not possible to develop single models encompassing adult males and females, and seedlings; but high accurate predictive models of LA from L × W measurements were developed for adult males (R2 = 0.98, PE = 0.69, n = 350), adult females (R2 = 0.98, PE = 0.01, n = 350), and seedlings (R2 = 0.99, PE = 6.80, n = 150). 相似文献
89.
Recreational Multifunctionality refers to those farms providing at least one recreational service to members of the farm household
or the public. Based on the types of recreational services offered, two types of landowners have been identified: Productivists and Ruralists. They differ on their extent of Recreational Multifunctionality, farm household attributes and farm representation. Both
types of landowners also have different behavior and understanding of agroforestry. This study builds on the Recreational
Multifunctionality construct to identify message content, channels and agencies that can better facilitate the diffusion of
agroforestry. In 2006, 353 randomly selected landowners from Missouri were interviewed and clustered in two groups: Productivists (38.0%) and Ruralists (62.0%). These groups were examined to identify differences regarding their perceptions of being a good farmer (i.e., message
content); their preferred source of information (i.e., communication channel); and their preferred agencies for learning purposes
(i.e., communication agencies). Study results show differences between Productivists and Ruralists in all three aspects of diffusion examined (i.e., message content, channels and agencies), suggesting that all landowners
should not be approached in the same way when promoting agroforestry. Messages conveyed to Productivists should emphasize the economic benefits of agroforestry, while messages to Ruralists should emphasize the conservation benefits of agroforestry. Touring farms with active tree management is a good way to disseminate
agroforestry practices among Productivists while state and federal extension agents appear to be more suitable to approach Ruralists. Both groups can effectively be reached using printed materials, especially through official conservation magazines. 相似文献
90.
Carla M. Koretsky Andrew MacLeod Ryan J. Sibert Christine Snyder 《Water, air, and soil pollution》2012,223(3):1415-1427
Redox stratification, especially hypolimnetic anoxia resulting from eutrophication, and salinization resulting from application
of salts for road deicing is investigated in three kettle lakes in southwest Michigan. Two of the lakes (Asylum and Woods
Lakes) are located in urban Kalamazoo, Michigan, and the third (Brewster Lake) is located in rural Hastings, Michigan. In
summer, the water columns of all three lakes are distinctly redox stratified, with anoxic hypolimnia and significant accumulation
of reduced solutes (e.g., Mn(II), Fe(II), ammonia) in the lake bottom waters. Extremely elevated conductivity, chloride, sodium,
and potassium levels are observed in the urban Asylum and Woods Lakes compared to the rural Brewster Lake, presumably due
to runoff of road salt deicers applied in the surrounding watershed. These significant changes in water quality are of concern
because they may detrimentally impact lake mixing, biodiversity, and ecosystem function in the urban lakes. 相似文献