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101.
The aim of this study is to determine the effect of approach direction and pace on flight distance of beef breeding cows. Five Japanese Black breeding cows were used as experimental cattle. Three approach directions were tested; that were the approach toward the head of the test cow from the front direction (FRONT), the approach toward to the foreleg of the test cow from the right or left (SIDE) and the approach toward to hind‐leg of the test cow diagonally from the right or left rear (BACK). Three levels of approach pace were also tested; that were the approach at a pace of 7 km/h, the approach at a pace of 4 km/h, and the approach at a pace of 1 km/h. The shortest distance between observer and cow's at the moment of the cow's withdrawal was defined as the flight distance. The flight distance in FRONT was significantly shorter than that in SIDE. The effect of the approach pace was significant. The faster an observer approached to cow, the greater the flight distance shown by the cow. The manner of approach to cattle markedly affects the flight distance. Therefore, the manner of approach to cattle must be standardized to measure flight distance for sharing results obtained by several researchers under various conditions.  相似文献   
102.
We used conventional cross-breeding techniques to develop a carnation with low ethylene sensitivity. A time-lapse video recording system for evaluating ethylene sensitivity of flowers, developed in our earlier study, proved useful for this breeding. We selected 10 new ethylene-resistant lines, in addition to the previously selected line 64–54. Lines 902–48a, 234–43S, and 234–36S showed extremely low ethylene sensitivity. The response time to 10 μL L−1 ethylene of these three lines exceeded 50 h in two independent experiments (2004 and 2005), whereas that of three sensitive control cultivars (‘White Sim’, ‘Excerea’, and ‘Scania’) was 6.2–8.0 h. The mean vase life of the ethylene-resistant lines ranged from 7.6 to 12.7 days (1.4–2.3 times that of ‘White Sim’). The application of ethylene to carnation flowers induced autocatalytic ethylene production in both petals and gynoecia of 9 of the 11 ethylene-resistant lines without petal wilting, indicating that the autocatalytic ethylene production was regulated independently of the petal wilting reaction. This result further suggests that these lines have normal ethylene receptors and produce ethylene autocatalytically, but their petal wilting reaction stops at a point beyond the receptor. Two lines (118–64S and 120–69S) showed extremely low ethylene production at flower senescence and very low autocatalytic ethylene production from petals and gynoecia.  相似文献   
103.
An R664X nonsense mutant AE1 is responsible for dominant hereditary spherocytosis in cattle and is degraded by the proteasomal endoplasmic reticulum-associated degradation. The present study demonstrated that R664X AE1 translated in vitro had the trypsin-sensitve site identical to that of the wild-type AE1. The P661S/R664X mutant containing a possible N-glycosylation site at Asn660 showed an increase in size by 3 kDa both in the cell-free translation system and in transfected HEK293 cells. Moreover, steady state levels of R664X and P661S/R664X in HEK293 cells were markedly increased in the presence of a proteasome inhibitior. These findings indicate that the truncated C-terminal region of R664X AE1 has lumenal localization in the endoplasmic reticulum and is not accessible to proteasomal machineries in the cytosol.  相似文献   
104.
We investigated the population density and range use of sika deer,Cervus nippon, on Mt. Ohdaigahara, central Japan, from July 1996 to July 1997. The deer population density estimated by the block count was high at 17.5–30.9 deer/km2. Although the deer remained this area from spring to fall, they moved out in winter, probably because of deep snow. A spotlight count showed that the deer prefer the eastern area as spring-summer range, where the forest consists of coniferous trees over a floor cover ofSasa nipponica, andS. nipponica grassland. The deer also use dense coniferous forest for cover, especially in summer and fall. Part of this study was presented at the 108th Annual Meeting of the Japanese Forestry Society (1997). This study was financially supported by the Environment Agency, Japan.  相似文献   
105.
The proton budgets of deciduous and coniferous forest ecosystems on volcanogenous regosols in Hokkaido, northern Japan, were studied by measuring the biogeochemical fluxes (atmospheric deposition, canopy leaching, vegetation uptake and leaching from soil) at each site during a three year period. The proton budgets were developed for individual compartments of the ecosystem: vegetation canopy, organic and mineral soil layers. At both sites, atmospheric S deposition was the dominant proton source in the vegetation canopy. In organic horizons, dissociation of weak acids (bicarbonate and/or organic acids) and vegetation uptake of base cations were the dominant proton sources, and the net mineralization of base cations was the dominant proton sink. Atmospheric acid deposition was almost neutralized in the forest canopy and organic horizon. At both sites, weathering and/or ion exchange of base cations and protonation of weak acids (mainly bicarbonate) were the dominant proton sinks in the mineral soil. In both organic and mineral soil, internal proton sources (mainly vegetation uptake of base cations and dissociation of weak acids) exceeded external proton sources, indicating that acid deposition was not the main driving force of soil acidification in the studied forest ecosystems.  相似文献   
106.
Sarcocystis hominis was first isolated from slaughtered cattle raised in Japan. Cysts were 1,220-4,460 x 80-384 microns in size and their wall was 3 to 6 microns thick and appeared radially striated in the histopathological sections because of the presence of palisade-like villar protrusions on the surface. The protrusions were 3.1-4.3 x 0.7-1.1 microns in size and had many microtubules in the core. Two cynomolgus monkeys, Macaca fascicularis, fed with the Sarcocystis cysts began to pass sporocysts, which measured a size of 14.3-15 x 9.5-10 microns, in the feces 10 days after ingestion.  相似文献   
107.
Codend selectivity for the jack mackerel Trachurus japonicus and the whitefin jack Kaiwarinus equula were evaluated based on data from trouser trawl experiments carried out in the East China Sea, using a test codend of 60 mm diamond mesh and a control codend made of minnow net with a square mesh of 9 mm bar length. Between-haul variations in parameters and the mean selection curves were tested with the catch data in the SELECT approach, and then the model of between-haul variation in the split parameter with the mean selection curve was chosen as the best fit using Akaike’s information criterion model selection. The 50% retention lengths and the selection ranges were 11.4 and 3.36 cm for jack mackerel and 8.83 and 0.93 cm for whitefin jack, respectively. The selection curve for whitefin jack was sharp, whereas that for jack mackerel was relatively wide. As the estimated split parameters indicated, about 80% of the whitefin jack entered the control codend, but 85 and 90% of the jack mackerel entered the control codend in the second and third hauls, respectively. The inequality in the split parameter is discussed from the viewpoint of the animal’s swimming behavior and water movement based on underwater video observations.  相似文献   
108.
The red alga Kappaphycus alvarezii is economically important as an edible species and as a source of carrageenan, and has been extensively cultivated in many tropical countries. For this species, different color strains, which differ from each another in growth rate and carrageenan content, have been reported for decades. In this study, lectins from brown, red, and green strains of K. alvarezii cultivated in Vietnam were isolated and characterized for evaluation of their biochemical properties and contents. The results showed that each color strain contained in common the three lectins, named KAA-1, KAA-2, and KAA-3, which shared the hapten-inhibition profile of hemagglutination, 20 N-terminal amino acid sequence, and equivalent molecular mass within a range of 28,016 ± 1.2 to 28,021 ± 1.8 Da, but differed in their yields, with the highest yield of KAA-2. These properties of the three isolectins were also comparable among the three different color strains. However, the sum of the yields of the three isolectins decreased in the order: red (21.4 mg) to green (15.9 mg) to brown strains (15.1 mg), from 500 g fresh alga. Thus, this algal species can be a good source of useful lectins, irrespective of color strain.  相似文献   
109.
In an effort to determine genus- or species-level taxonomic profiles and diversity of bacterial consortia in the Tama River around urban Tokyo, next-generation sequencing technology targeting a 16S ribosomal RNA (rRNA) gene amplicon was employed. Metagenomic analysis performed by an Ion Personal Genome Machine after sequentially filtering samples through 5-, 0.8- and 0.2-μm filters yielded 1.48 Gb of 16S sequences (average 2.38 M reads/sample). The results indicated that half of the bacterial sequences belonged to Proteobacteria, followed by Bacteroidetes, Actinobacteria and Cyanobacteria. Flavobacterium (Bacteroidetes), possibly including a potential fish pathogen, was the most numerous genera in the Tama River metagenome, and accounted for?~?16% of assigned 16S reads, followed by Mycobacterium. Other dominant bacterial genera including Zoogloea, Sediminibacterium, Hyphomicrobium, Sphingopyxis, Thiothrix and Lysobacter, were thought to be associated with waste water and sludge. MiSeq metagenomic analysis revealed that environmental factors, particularly water temperature, influenced the bacterial composition throughout the year, with a strong negative correlation observed for Proteobacteria and a positive correlation for Bacteroidetes. In terms of bacterial genera, Flavobacterium was positively correlated with temperature, while Polaromonas, Pseudomonas and Bradyrhizobium were negatively correlated with this, suggesting dynamic change in the free-living bacterial population throughout the year and versatile adaptation strategies in relation to environmental factors.  相似文献   
110.
In coral mariculture, growth is one of the most common ways to track success. However, numerous methods of monitoring coral growth make comparative studies challenging. A literature review of 39 studies from 1982 to 2017 indicated that the most predominant non‐invasive methods used were linear and areal measurement and these were evaluated for their accuracy using nursery‐reared corals. The monthly change in linear and areal growth rates of six coral species (= 215), Pocillopora acuta, Hydnophora rigida, Merulina ampliata, Podabacia crustacea, Echinopora lamellosa and Platygyra sinensis were measured via photogrammetry. We tested whether the planar area of coral colonies can be estimated using three geometric formulas of linear measurements. Based on the literature review, the six types of measurement methods were namely linear, volume, weight, area, count of polyps/branches and calcification, in decreasing order of application. Our results showed that the change in area calculated by geometric mean diameter (GMD) formulas provided the most accurate estimation among the three formulas and was strongly correlated with planar area (R2 ≥ .60; p < .05) for all coral species, except E. lamellosa and Pl. sinensis. However, our findings suggest that it is not ideal to use geometric formulas to estimate the change in area. Instead, we posit that areal photogrammetry represents the simplest yet accurate non‐invasive method for rapid monitoring of extensive areas of corals in situ. Lastly, we discuss the recommendations and limitations for areal photogrammetry.  相似文献   
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