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排序方式: 共有326条查询结果,搜索用时 93 毫秒
191.
Martini Mina Altomonte Iolanda Sommer Matteo Federico Gili Claudia Biancani Barbara Licitra Rosario Salari Federica 《Veterinary research communications》2022,46(2):577-583
Veterinary Research Communications - Research data on milk composition in cetaceans are scattered and fragmentary. This paper analyses the gross and mineral composition, the fatty acids profile and... 相似文献
192.
We report on a wind-tunnel study with 1 : 75 scale model treesdesigned to examine the influence of canopy structure on theformation of turbulent gusts above forests. This was to testthe hypothesis that more irregular canopy structures produceless intense gusts because the change in wind speed with heightat canopy top is less severe. Measurements were made of windspeeds and turbulence within and above the model forests andof the wind loading on model trees in four different silviculturalsystems. The systems tested were even-aged, single-tree selection,shelterwood/group selection and strip felling. The measurementsshowed that the profiles of different mean wind and turbulencecharacteristics above the forests are remarkably similar whenvertical heights are normalized by the height of the tallesttree but differences do exist within the canopy. The wind loadingmeasurements indicated no difference between the systems interms of stability except possibly for the shelterwood/groupselection. In the shelterwood/group selection system the presenceof smaller sub-canopy trees appears to reduce the loading onthe main canopy trees either by providing support and increasingdamping or by absorption of energy from the canopy-penetratinggusts. 相似文献
193.
Sierra-de-Grado R Pando V Martínez-Zurimendi P Peñalvo A Báscones E Moulia B 《Tree physiology》2008,28(6):835-846
Stem straightness is an important selection trait in Pinus pinaster Ait. breeding programs. Despite the stability of stem straightness rankings in provenance trials, the efficiency of breeding programs based on a quantitative index of stem straightness remains low. An alternative approach is to analyze biomechanical processes that underlie stem form. The rationale for this selection method is that genetic differences in the biomechanical processes that maintain stem straightness in young plants will continue to control stem form throughout the life of the tree. We analyzed the components contributing most to genetic differences among provenances in stem straightening processes by kinetic analysis and with a biomechanical model defining the interactions between the variables involved (Fournier's model). This framework was tested on three P. pinaster provenances differing in adult stem straightness and growth. One-year-old plants were tilted at 45 degrees, and individual stem positions and sizes were recorded weekly for 5 months. We measured the radial extension of reaction wood and the anatomical features of wood cells in serial stem cross sections. The integral effect of reaction wood on stem leaning was computed with Fournier's model. Responses driven by both primary and secondary growth were involved in the stem straightening process, but secondary-growth-driven responses accounted for most differences among provenances. Plants from the straight-stemmed provenance showed a greater capacity for stem straightening than plants from the sinuous provenances mainly because of (1) more efficient reaction wood (higher maturation strains) and (2) more pronounced secondary-growth-driven autotropic decurving. These two process-based traits are thus good candidates for early selection of stem straightness, but additional tests on a greater number of genotypes over a longer period are required. 相似文献
194.
Eunice Badu James S. Kaba Evans K. Dawoe O. Agbenyega Rex V. Barnes 《Journal of plant nutrition》2013,36(19):2407-2422
AbstractMaize (Zea mays L.) is a major nitrogen consuming crop, as nitrogen is considered as an important determinant of its grain yield. Though inorganic fertilizer is widely recommended, the problem of high cost and inaccessibility limit its usage by resource poor farmers. Biochar application provides a new technology for both soil fertility and crop productivity improvement. With limited research on the suitability of biochar for soil improvement practices in Ghana, our objective was to determine the synergistic effect of biochar and inorganic fertilizer on the nitrogen uptake, nitrogen use efficiency, and yield of maize. Field experiment was conducted in Ghana, KNUST, in the major and minor raining seasons. Biochar was applied at 0, 5, 10, 15, and 20 t ha?1 and fertilizer N applied at 0, 45, and 90?kg ha?1. The results showed significantly (p?.05) higher N uptake, N use efficiency and yield of maize when biochar was applied with fertilizer N compared to both the control and sole N fertilizer plots. Biochar applied at 10 t ha?1 supplemented with 45?kg N ha?1 increased N uptake by 200%, and grain yield by 213% and 160% relative to the control in the minor and major rainy seasons, respectively. The greater yield of maize recorded on biochar-amended soils was attributed to the improved N uptake and nitrogen use efficiency. In conclusion, our finding suggests that the application of combined biochar and inorganic N fertilizer is not only ecologically prudent, but economically viable and a practicable alternative to current farmers’ practice of cultivating maize in Ghana. 相似文献
195.
196.
Rex Brennan Linzi Jorgensen Christine Hackett Mary Woodhead Sandra Gordon Joanne Russell 《Euphytica》2008,161(1-2):19-34
The first genetic linkage map of blackcurrant (Ribes nigrum L.) was constructed using AFLP, SSR (genomic and EST-derived) and SNP markers, in a mapping population derived from two diverse
breeding clones of blackcurrant from the SCRI breeding programme. Cluster analysis of the population revealed that the individuals
within the population formed two distinct sub-populations, with segregation ratios consistent with one sub-population having
the two intended parents, and the other being selfed segregants. The latter sub-population improves the map by providing a
more informative estimate of recombination frequency than the crossed sub-population for some marker configurations, and also
revealed the presence of two unlinked loci affecting viability. Several important phenological, agronomic and fruit quality
traits were evaluated in the mapping population, and QTLs affecting these are located on the linkage map. This provides a
framework for the development of marker-assisted breeding strategies for blackcurrant, to improve breeding efficiency and
time to cultivar. 相似文献
197.
Mario Armando Gómez-Favela Roberto Gutiérrez-Dorado Edith Oliva Cuevas-Rodríguez Vicente Adrián Canizalez-Román Claudia del Rosario León-Sicairos Jorge Milán-Carrillo Cuauhtémoc Reyes-Moreno 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(4):345-352
Chia (Salvia hispanica L.) plant is native from southern Mexico and northern Guatemala. Their seeds are a rich source of bioactive compounds which protect consumers against chronic diseases. Germination improves functionality of the seeds due to the increase in the bioactive compounds and associated antioxidant activity. The purpose of this study was to obtain functional flour from germinated chia seeds under optimized conditions with increased antioxidant activity, phenolic compounds, GABA, essential amino acids, and dietary fiber with respect to un-germinated chia seeds. The effect of germination temperature and time (GT = 20–35 °C, Gt = 10–300 h) on protein, lipid, and total phenolic contents (PC, LC, TPC, respectively), and antioxidant activity (AoxA) was analyzed by response surface methodology as optimization tool. Chia seeds were germinated inside plastic trays with absorbent paper moisturized with 50 mL of 100 ppm sodium hypochlorite dissolution. The sprouts were dried (50 °C/8 h) and ground to obtain germinated chia flours (GCF). The prediction models developed for PC, LC, TPC, and AoxA showed high coefficients of determination, demonstrating their adequacy to explain the variations in experimental data. The highest values of PC, LC, TPC, and AoxA were obtained at two different optimal conditions (GT = 21 °C/Gt = 157 h; GT = 33 °C/Gt = 126 h). Optimized germinated chia flours (OGCF) had higher PC, TPC, AoxA, GABA, essential amino acids, calculated protein efficiency ratio (C-PER), and total dietary fiber (TDF) than un-germinated chia seed flour. The OGCF could be utilized as a natural source of proteins, dietary fiber, GABA, and antioxidants in the development of new functional beverages and foods. 相似文献
198.
M.A.E. Rex M.A. Vet.M.B. M.R.C.V.S. 《New Zealand veterinary journal》2013,61(7):94-95
Abstract Extract Hydronephosis is a relatively rare condition in the cat (Imhoff, 1964; Bloom, 1954). The case reorted here is of interest because the abnormality was only discovered when the animal was presented at the hospital for removal of an abdominal testicle, the owner having noted no signs of ill health referable to the kidney lesion. 相似文献
199.
M.A.E. Rex M.A. Vet.M.B. M.R.C.V.S. 《New Zealand veterinary journal》2013,61(2):45-46
Extract The use of an intra-medullary pin for repair of a midshaft fracture of the dog's femur is usually followed by excellent bone healing. Untoward sequelae may follow poor technique, or the use of pins in cases in which other techniques are indicated. This communication records an unusual sequel to intra-medullary pinning which the writer has not observed previously. 相似文献
200.
James G. Carew Trudi Gillespie Julie White Henry Wainwright Rex Brennan Battey Nick 《The Journal of Horticultural Science and Biotechnology》2013,88(5):504-509
SummaryWalnut (Juglans regia L.) leaves provide a source of healthy compounds, phenolics, which could be useful for the prevention of diseases in which free radicals are involved. In this study, walnut leaves from 14 different cultivars were studied for their total phenolics contents and anti-oxidant activities. Anti-oxidant activities were evaluated by measuring the scavenging activities of leaf extracts against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The total phenolics contents of the cultivars ranged from 17.7 mg gallic acid equivalents (GAE) g–1 FW to 39.6 mg GAE g–1 FW. The highest scavenging activities were found in methanol extracts of walnut leaves. Total phenolics contents were highly correlated with anti-oxidant activity (R2= 0.94 – 0.92). 相似文献