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The ash content and the content of Ca, Mg, K, and Na in the bristles of pigs is influenced by the age of the animal and by the season of the year. The peak concentrations of ash, Ca and Mg in the bristles of eight boars (cut every month) were found in June, shortly before the change in hair coat. (P less than 0.05-0.001). The concentrations of K and Na in the bristles deviated functionally from the change in the hair coat. In the first half of the year the bristles of the boars contained significantly more K and Na than in the second half. Values for the elements P, Zn, Fe, Cu, and Mn were subject to great variations through the year. These variations were found to be different with different animals. The influence of endogenic factors on the Mn content of the bristles was particularly striking, also in regard of the order of magnitude. The processes of Mn metabolism in the bristles are obviously still archaic in origin and would thus only allow to make comparison with other values of the mineral content of bristles at the very time of sampling. Differences in the P, Zn, Fe and Cu content of bristles in the different months were, in some instances, statistically significant although variations in the annual mean values were found to be relatively small. 相似文献
113.
M Grün M Anke A Hennig W Seffner M Partschefeld G Flachowsky B Groppel 《Archives of Animal Nutrition》1978,28(5):341-347
Lambs received 250, 1000 and 1750 mg Fe per kg concentrate dry matter. The Fe-supplementations caused the Fe-levels of spleen, liver, kidneys and ribs to rise significantly. Liver and spleen reflected most markedly the high Fe-supply. The Fe-supplementation reduced the Cu-content in the liver and the share of Zn in the kidneys. The Mn-content of all body parts analysed was not significantly influenced by Fe-supplementation. 相似文献
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Vadivel V Nandety A Biesalski HK 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):245-253
The methanolic extract of Cassia hirsuta L. seed materials, an underutilized food legume collected from India, was analyzed for antioxidant activity and health relevant functionality. The methanolic extract of raw seeds contained a total free phenolic content of 15.82?±?1.69 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1,446 mmol Fe[II]/mg extract), inhibition of ß-carotene degradation (48.81%) and scavenging activity against DPPH (64.40%) and superoxide (43.78%) radicals were exhibited by the raw samples. Further, 83.11% of α-amylase and 62.79% of α-glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay were also recorded. Sprouting + oil-frying caused an apparent increase on the total free phenolic content and a significant improvement in the antioxidant and free radical scavenging capacity of methanolic extract of C. hirsuta seeds, while soaking + cooking as well as open-pan roasting treatments showed diminishing effects. The analysis of the phenolic profile revealed the presence of gallic acid, p-coumaric acid and (+)-catechin in the methanolic extract of these seeds. 相似文献
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Determining some parameters of capillary moisture transport in porous building materials. Part 3: Tests on mortars and sands Because a mortar component ultimately belongs to brickwork, the contribution of sand, which serves as an aggregate, to capillary liquid rise was investigated. Since up to now this kind of transport can only be observed with difficulty, as also confirmed by experiment, due to complex interaction of the individual characteristic values, an attempt was made to also enhance present experience on other material than brick. 相似文献
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Intensification of weather extremes is currently emerging as one of the most important facets of climate change. Research frontiers are in analyzing (1) the consequences for the hydrological cycle and (2) the effects of multifactor scenarios on ecosystems. However, in all theoretical and experimental scenarios, challenges arise as to how precipitation regimes translate into variation in soil moisture. Here, we explore soil‐moisture response to experimental changes in the precipitation regime in Central Europe over a period of 5 y, particularly focusing on the effects of recurrent extreme weather events. Intraannual difference in weekly precipitation sums imposed by extreme‐drought or heavy‐rainfall manipulations clearly exceeded interannual variation in the ambient precipitation pattern during the growing season between 2005 and 2009. However, soil‐moisture variability in the experimental plots did not clearly reflect any altered patterns in response to the manipulated precipitation regime. Natural variation in soil moisture between years was similar to within‐season differences between manipulations. Strong differences in soil‐moisture dynamics during the growing season can, however, be generated by changing the temporal distribution of rainfall events while keeping the magnitude of the precipitation sum constant. Our findings confirm a common methodological dilemma in precipitation‐change experiments searching for a logical way to determine how precipitation change affects communities and ecosystems on relatively short time scales: Alteration of weather regimes according to extreme‐value statistics and future scenarios vs. systematic alteration of soil moisture. For Central Europe, our data suggest that other factors rather than the magnitude of rainfall exclusion or addition would appear to be decisive for ecosystem response to more extreme precipitation regimes. Response of soil moisture to frequency, return interval, and timing of events is a promising approach for further exploration. In addition, buffer capacity of the ecosystem under study has to be taken into account. 相似文献