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951.
Hee Ock Boo Jeong Hun Park Hag Hyun Kim Soo Jeong Kwon Sun Hee Woo 《Journal of Crop Science and Biotechnology》2018,21(2):183-191
This study was executed to evaluate the phenolic content, DPPH, ABTS radical scavenging rate, nitrite scavenging rate, and anti-inflammatory activity from in vitro cultured adventitious root extract of different Platycodon grandiflorum(PG) variety. Total polyphenol and flavonoid content showed the highest amount in adventitious root extract of tetraploid PG, and followed by green petal, double petal and diploid PG extract. The DPPH radical scavenging activity showed that the increase was proportional to the concentration, especially, the scavenging activity at a concentration of 10 mg mL-1 was higher than 80%. The ABTS radical scavenging activity was not significantly different among the PG varieties at the concentration of 5 mg mL-1 or more, and generally showed high scavenging activity. The nitrite scavenging activity was affected by pH, at pH of 1.2, the scavenging effect of all of the extracts tested observed higher than that of the other two pH ranges. The cytotoxicity of PG extract at various concentrations, the survival rate of RAW 264.7 cell was more than 90% at a concentration of 200 μg mL-1 or less, and it was confirmed that the macrophage cell showed little toxicity. After PG extract pretreatment at 50, 100, and 200 μg mL-1, LPS-treated experimental group significantly inhibited NO production in a dose-dependent manner. The dose-response trends followed quadratic regressions in all PG varieties. The PG extracts showed a considerable range of influence on cytokine secretion. The effect of adventitious root extracts of PG against inflammatory mediators TNF-α, IL-6 and IL-1β production showed the most significant anti-inflammatory activity. 相似文献
952.
Standardized total tract digestibility of phosphorus in various inorganic phosphates fed to growing pigs
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An experiment was conducted to determine the standardized total tract digestibility (STTD) of phosphorus (P) in five sources of inorganic phosphate fed to growing pigs, including dicalcium phosphate (DCP), monodicalcium phosphate (MDCP), monocalcium phosphate (MCP), tricalcium phosphate (TCP) and monosodium phosphate (MSP, reagent grade). Six barrows (42.4 ± 1.1 kg) individually housed in metabolism crates were allotted to a 6 × 6 Latin square design with six dietary treatments and six periods. Each experimental period consisted of a 4 day adaptation period and a 5 day collection period. The five experimental diets contained 0.24 to 0.34% of P from each inorganic phosphate as a sole source of P. A P‐free diet was also prepared to estimate the basal endogenous loss of P. The STTD of P in MSP (94.9%) was not different from the STTD of P in MCP (93.0%), but was greater (P < 0.05) than that in DCP, MDCP and TCP (87.0, 86.5 and 71.3%, respectively). In conclusion, digestibility of P in reagent‐grade MSP was greater than that in feed‐grade inorganic phosphates such as DCP, MDCP and TCP, and digestibility of P in DCP and MDCP was greater than that in the TCP. 相似文献
953.
Rebecca Lewis Cerrie A. Sherfield Christopher R. Fellows Rachel Burrow Iain Young Alex Dugdale 《Veterinary anaesthesia and analgesia》2017,44(3):567-576
Objective
To determine the frequency of provision and main providers (veterinary surgeons, nurses or trainees) of manual ventilation in UK veterinary practices. Furthermore, to determine the variation in peak inspiratory (inflation) pressure (PIP), applied to a lung model during manual ventilation, by three different groups of operators (inexperienced, experienced and specialist), before and after training.Study design
Questionnaire survey, lung model simulator development and prospective testing.Methods
Postal questionnaires were sent to 100 randomly selected veterinary practices. The lung model simulator was manually ventilated in a staged process over 3 weeks, with and without real-time biometric feedback (PIP display), by three groups of volunteer operators: inexperienced, experienced and specialist.Results
The questionnaires determined that veterinary nurses were responsible for providing the majority of manual ventilation in veterinary practices, mainly drawing on theoretical knowledge rather than any specific training. Thoracic surgery and apnoea were the main reasons for provision of manual ventilation. Specialists performed well when manually ventilating the lung model, regardless of feedback training. Both inexperienced and experienced operators showed significant improvement in technique when using the feedback training tool: variation in PIP decreased significantly until operators provided manual ventilation at PIPs within the defined optimum range. Preferences for different forms of feedback (graphical, numerical or scale display), revealed that the operators’ choice was not always the method which gave least variation in PIP.Conclusions and clinical relevance
This study highlighted a need for training in manual ventilation at an early stage in veterinary and veterinary nursing careers and demonstrated how feedback is important in the process of experiential learning. A manometer device which can provide immediate feedback during training, or indeed in a real clinical setting, should improve patient safety. 相似文献954.
Eric O. Young Donald S. Ross Bruce R. Hoskins 《Communications in Soil Science and Plant Analysis》2017,48(20):2434-2446
Colorimetric P determination mainly reflects inorganic P, whereas inductively coupled plasma spectroscopy (ICP) measures all P in solution. We compared Morgan extractable P for ICP (MP-ICP) and colorimetry (MP-Color) using dairy farm field samples (0 to 20 cm) across northern New York (n = 250) and hayfield transect samples (0–15, 15–30, 45–50 cm; n = 164). Soil organic matter, pH, and extractable cations were also measured. Mean ratio of MP-ICP: MP-Color was 1.46 and differed significantly among Morgan P categories, ranging from 1.89 for low to 1.06 for very high. The numeric difference between MP-ICP and MP-Color ranged from 0 to 12.9 mg kg?1. Organic matter, Al, and pH jointly accounted for 55% of the variability between methods across samples. Fertilizer P recommendations differed based on the two methods, suggesting results from both methods should be reported, particularly in the responsive range. 相似文献
955.
Blended nanofiber webs of poly(L-lactic acid) (PLLA)/poly(L-lysine) (PLys) with a PLys content of up to 3 % were prepared using an electro-spinning process with trifluoroacetic acid
as the spinning solvent, and employed as a substrate for silicification. Silica formation on the surface of the PLLA/PLys
nanofibers was carried out by immersing the nanofiber webs in silicic acid solutions at various concentrations for different
times. The effects of the silicification conditions and PLys content on silicification were examined by scanning electron
microscopy, FT-IR, energy dispersive spectroscopy, and the increase in weight of the substrates. Although the amount of silica
formed on the PLLA nanofibers increased with increasing silicification time and silicic acid concentration, the uniformity
of the coated layer was not controlled. However, the incorporation of small amounts of PLys in the PLLA nanofibers increased
the amount and uniformity of the silica formed on the nanofibers. 相似文献
956.
The dyeing and color fastness properties of three reactive-disperse dyes containing a sulphatoethylsulphone group on Nylon,
cotton and N/C mixture fabrics were examined. Reduction-clearing was more effective in removing the unfixed dyes than soaping
since the reactive-disperse dye became hydrophobic during dyeing process. Nylon was dyed well with three reactive-disperse
dyes at pH 5∼8 and difference in chemical structure between dyes did not affect the final color strength of the dyed Nylon
fiber, but their build-up properties on Nylon were not so good. The color strength of the dyed cotton was not as high as that
of Nylon. The color strength of cotton increased by lowering dyeing temperature when the reactive-disperse dyes having hydroxy
group were used. Nylon absorbed more dye molecules than cotton in simultaneous dyeing, the color difference between Nylon
and cotton could be reduced as the dyeing temperature decreased. N/C mixture fabric was dyed well at 60 °C with the reactive-disperse
dyes having hydroxyl group when applied at pH 7 and 60 °C, and their build-up properties were good. It was also found that
washing fastness and rubbing fastness of dyed Nylon, cotton and N/C fabrics with the reactive-disperse dyes were excellent,
while light fastness was moderate. 相似文献
957.
This study investigated the main origin of the thermochromism of a novel compound, 1,3-bis(hydroxyethylamino)-4,6-dinitrobenzene
(BDB). In order to unravel the relative dependence of reversible color change between yellow and orange on proton transfer
reaction and crystal-crystal phase transformation, kinetic experiments were executed. The recovery rates of thermochromic
transition, proton transfer reaction, and crystal-crystal phase transformation were calculated from the data measured through
UV-vis spectrophotometry, IR spectrometry, and X-ray diffractometry with a lapse of time at fixedtemperatures (30, 40, and
50 °C) after cooling from heated temperature (150 °C). The kinetic experiments revealed that the recovery takes place more
quickly at lower temperature. At each fixed-temperature, the recovery rate is in the order of the crystal-crystal phase transformation
> the proton transfer reaction > the thermochromic transition. It is concluded that the proton transfer reaction is the main
origin for thermochromism of BDB in solid state and the crystal-crystal phase transformation is a collateral one. 相似文献
958.
Valerie H. Teetor Denise V. Duclos Elisabeth T. WittenbergKelly M. Young Jeerawan ChawhuaymakMark R. Riley Dennis T. Ray 《Industrial Crops and Products》2011,34(2):1293-1300
Sweet sorghum (Sorghum bicolor (L.) Moench) is an annual crop currently being investigated for biofuel production in the arid southwest United States (U.S.). Sweet sorghum is an ideal candidate because it can be grown under reduced inputs (water, fertilizer) and responds more efficiently to stresses than traditional crops. Many varieties have been bred for high sugar, syrup, and forage production, but much biodiversity still remains to be utilized.Studies performed in 2006 and 2007 found that high biomass and percent juice extracted were the best predictors of potential ethanol yield per area. This investigation was undertaken to determine what effects planting dates have on overall sugar and predicted ethanol yields.Four varieties (Dale, M81E, Theis, and Topper) were planted in April, May, June, and July of 2008. They were harvested at physiological maturity, with dates ranging from August 26 to December 2. Biomass, juice weight, and Brix of the juice were recorded in the field. Samples were analyzed in the laboratory by High Performance Liquid Chromatography (HPLC) for fructose, glucose, and sucrose.Theoretical ethanol yields were calculated based on biomass, juice weight, and percent sugar. These were compared to actual yields obtained from laboratory-scale fermentations of the harvested juice, which ranged from 7.4% to 11.2% (58.1-88.6 g L−1). Since our predictive model uses the maximum conversion rate of sugar to ethanol and this was not reached in the lab, the predicted yields were always higher than the actual yields. However, the model can be a useful tool for estimating ethanol yield per area.Total sugars and predicted ethanol production were influenced by planting date, but the degree of the effects depended on the cultivar planted. Overall a May planting date at this location is preferable due to consistently higher values for the yield components analyzed, and Theis is not recommended due to its high susceptibility to heat. Sweet sorghum juice has been successfully fermented into ethanol, which indicates this crop may be able to play a transitory role in the emerging biofuel market. 相似文献
959.
Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing. 相似文献
960.
The H5N1 type A influenza viruses classified as Qinghai-like virus (clade 2.2) are a unique lineage of type A influenza viruses with the capacity to produce significant disease and mortality in gallinaceous and anseriform birds, including domestic and wild ducks. The objective of this study was to determine the susceptibility and pathogenesis of chickens and domestic ducks to A/Whooper Swan/Mongolia/224/05 (H5N1) high pathogenicity avian influenza (HPAI) virus when administered through respiratory or alimentary routes of exposure. The chickens and ducks were more susceptible to the H5N1 HPAI virus, as evidenced by low infectious and lethal viral doses, when exposed by intranasal as compared to alimentary routes of inoculation (intragastric or oral-fed infected chicken meat). In the alimentary exposure pathogenesis study, pathologic changes included hemorrhage, necrosis, and inflammation in association with virus detection. These changes were generally observed in most of the visceral organs of chickens, between 2 and 4 days postinoculation (DPI), and are similar to lesions and virus localization seen in birds in natural cases or in experimental studies using the intranasal route. Alimentary exposure to the virus caused systemic infection in the ducks, characterized by moderate lymphocytic encephalitis, necrotized hepatitis, and pancreatitis with a corresponding demonstration of virus within the lesions. In both chickens and ducks with alimentary exposure, lesions, virus, or both were first demonstrated in the upper alimentary tract on 1 DPI, suggesting that the alimentary tract was the initial site affected upon consumption of infected meat or on gavage of virus in liquid medium. However, as demonstrated in the infectivity study in chickens, alimentary infection required higher exposure doses to produce infection as compared to intranasal exposure in chickens. These data suggest that upper respiratory exposure to H5N1 HPAI virus in birds is more likely to result in virus infection and transmission than will consumption of infected meat, unless the latter contains high doses of virus, as found in cannibalized infected carcasses. 相似文献