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排序方式: 共有864条查询结果,搜索用时 15 毫秒
21.
Laddawan Krongpong Kunihiko Futami Takayuki Katagiri Makoto Endo Masashi Maita 《Fisheries Science》2008,74(5):1055-1061
Furazolidone, an antibacterial drug that was once widely used in the livestock industry and aquaculture, is now prohibited
in numerous countries. It is difficult to detect residual furazolidone because it is readily metabolized in animal tissues
but, by using and liquid chromatography coupled with tandem mass spectrometry, its metabolite, 3-amino-2-oxazolidinone (AOZ)
can be detected. Here we describe the validity of an enzyme-linked immunosorbent assay (ELISA) kit to detect AOZ in Japanese
eel Anguilla japonica tissue. ELISA is capable of detecting AOZ at 1.0 μg/kg in an eel sample with excellent accuracy and precision. Our results
show that ELISA is suitable for regulatory purposes and for studying the fate of AOZ residues in eel treated with furazolidone.
To measure the persistence of AOZ in eel tissues, eels (1.4–6.5g) were immersed in tanks containing 2 and 10 mg furazolidone/L
for 3 h, and then maintained in a tank supplying well water for the next 160 days. The half-lives of AOZ, calculated from
the linear terminal part of the excretion curve, were 25.0 days in muscle and 21.6 days in liver from fish exposed to 2 mg/L
furazolidone. In the eels treated with 10 mg/L furazolidone, by contrast, high levels of AOZ were detected in liver and muscle,
but the half-lives of AOZ were similar to those in fish treated with 2 mg/L furazolidone. The half-lives of AOZ in eel tissues
were prolonged by the condition of low water temperature. 相似文献
22.
Identification of reaction products of acylated anthocyanins from red radish with peroxyl radicals 总被引:2,自引:0,他引:2
Matsufuji H Otsuki T Takeda T Chino M Takeda M 《Journal of agricultural and food chemistry》2003,51(10):3157-3161
Red radish anthocyanin extract, which consists of 12 known acylated anthocyanins, was reacted with 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) to generate peroxyl radicals under acidic pH conditions at 37 degrees C. The reaction products were isolated using preparative HPLC, and their chemical structures were determined to be p-hydroxybenzoic acid (1), 6-O-(E)-p-coumaroyl-2-O-beta-d- glucopyranosyl-alpha-d-glucopyranoside (3), p-coumaric acid (4), 6-O-(E)-feruloyl-2-O-beta-d-glucopyranosyl-alpha-d-glucopyranoside (5), and ferulic acid (6). Some products were not identified. HPLC analyses of the mixture of acylated pelargonidin isolated from red radish and AAPH revealed that the acylated pelargonidins possess the radical scavenging ability on some common sites even if the characteristics of the intramolecular acyl units are different. Degradation rates of acylated pelargonidins and the formation rates of the resulting reaction products were found to be quite different. 相似文献
23.
24.
We determined the changes in the contents of three gamma-glutamyl peptides and four sulfoxides in garlic cloves during storage at -3, 4, and 23 degrees C for 150 days using a validated high-performance liquid chromatography method that we reported recently. When garlic was stored at 4 degrees C for 150 days, marked conversion of the gamma-glutamyl peptides, gamma-L-glutamyl-S-allyl-L-cysteine and gamma-L-glutamyl-S-(trans-1-propenyl)-L-cysteine (GSPC), to sulfoxides, alliin and isoalliin, was observed. Interestingly, however, when garlic was stored at 23 degrees C, a decrease in GSPC and a marked increase in cycloalliin, rather than isoalliin, occurred. To elucidate in detail the mechanism involved, the conversion of isoalliin to cycloalliin in both buffer solutions (pH 4.6, 5.5, and 6.5) and garlic cloves at 25 and 35 degrees C was examined. Decreases in the concentration of isoalliin in both the solutions and the garlic cloves during storage followed first-order kinetics and coincided with the conversion of cycloalliin. Our data indicated that isoalliin produced enzymatically from GSPC is chemically converted to cycloalliin and that the cycloalliin content of garlic cloves increases during storage at higher temperature. These data may be useful for controlling the quality and biological activities of garlic and its preparations. 相似文献
25.
Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil 总被引:2,自引:0,他引:2
To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, 13C CPMAS NMR spectra, and δ13C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and NaBH4+0.1 M Na4P2O7 (pH 10.5). It was found that the water- and 0.25 M Na2SO4-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH4+0.1 M Na4P2O7 (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields. 相似文献
26.
Okada Y Iimure T Takoi K Kaneko T Kihara M Hayashi K Ito K Sato K Takeda K 《Journal of agricultural and food chemistry》2008,56(4):1458-1464
The foam stability of beer is one of the important key factors in evaluating the quality of beer. The purpose of this study was to investigate the relationship between the level of malt modification (degradation of protein, starch, and so on) and the beer foam stability. This was achieved by examining foam-promoting proteins using two-dimensional gel electrophoresis (2DE). We found that the foam stability of beer samples brewed from the barley malts of cultivars B and C decreased as the level of malt modification increased; however, the foam stability of cultivar A did not change. To identify the property providing the increased foam stability of cultivar A, we analyzed beer proteins using 2DE. We analyzed three fractions that could contain beer foam-promoting proteins, namely, beer whole proteins, salt-precipitated proteins, and the proteins concentrated from beer foam. As a result, we found that in cultivar A, some protein spots did not change in any of these three protein fractions even when the level of malt modification increased, although the corresponding protein spots in cultivars B and C decreased. We analyzed these protein spots by peptide mass finger printing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. As a result, all of these spots were identified as barley dimeric alpha-amylase inhibitor-I (BDAI-I). These results suggest that BDAI-I is an important contributor to beer foam stability. 相似文献
27.
Harada Kousuke Kato Yuria Takahashi Jun Imamura Hiyoko Nakamura Natsume Nishina Atsuyoshi Phay Nyunt Tadaishi Miki Shimizu Makoto Kobayashi-Hattori Kazuo 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):103-109
Plant Foods for Human Nutrition - Adipose tissue is an endocrine organ and its endocrine function is closely associated with type 2 diabetes mellitus. Valeriana officinalis (Valerian) exerts some... 相似文献
28.
Shinichiro Ogawa Makoto Kimata Masamitsu Tomiyama Masahiro Satoh 《Journal of animal science》2022,100(3)
We estimated heritabilities of semen production traits and their genetic correlations with litter traits and pork production traits in purebred Duroc pigs. Semen production traits were semen volume, sperm concentration, proportion of morphologically normal sperms, total number of sperm, and total number of morphologically normal sperm. Litter traits at farrowing were total number born, number born alive, number stillborn, total litter weight at birth, mean litter weight at birth, and piglet survival rate at birth. Litter traits at weaning were litter size at weaning, total litter weight at weaning, mean litter weight at weaning, and piglet survival rate from birth to weaning. Pork production traits were average daily gain, backfat thickness, and loin muscle area. We analyzed 45,913 semen collection records of 896 boars, 6,950 farrowing performance records of 1,400 sows, 2,237 weaning performance records of 586 sows, and individual growth performance records of 9,550 animals measured at approximately 5 mo of age. Heritabilities were estimated using a single-trait animal model. Genetic correlations were estimated using a 2-trait animal model. Estimated heritabilities of semen production traits ranged from 0.20 for sperm concentration to 0.29 for semen volume and were equal to or higher than those of litter traits, ranging from 0.06 for number stillborn and piglet survival rate at birth to 0.25 for mean litter weight at birth, but lower than those of pork production traits, ranging from 0.50 for average daily gain to 0.63 for backfat thickness. In many cases, the absolute values of estimated genetic correlations between semen production traits and other traits were smaller than 0.3. These estimated genetic parameters provide useful information for establishing a comprehensive pig breeding scheme. 相似文献
29.
Takanobu Goto Shusaku Takagi Toshiaki Ichiki Tadashi Sakai Makoto Endo Terutoyo Yoshida Masaharu Ukawa Hisashi Murata 《Fisheries Science》2001,67(1):58-63
SUMMARY: The aim of this study was to investigate the cause of green liver in red sea bream fed substitute protein diets. Red sea bream Pagrus major was given either of the following diets for 28 weeks: (1) control diet (50% fish meal), (2) low level fish meal diet (15% fish meal), and (3) non-fish meal diet (0% fish meal). The green liver was observed in all groups tested, but the incidence was much higher in the experimental diet groups. The feeding of substitute protein diets reduced plasma triglyceride and cholesterol levels. However, there was no significant difference in plasma hepatic enzyme activities and plasma bile salts concentration among the treatments. Fish fed the substitute protein diets showed low hepatic taurine levels with an appearance of a biliverdin in the liver. Moreover, the proportion of ditaurobilirubin to total biliary bile pigments was significantly lower in fish fed the substitute protein diets. These data indicate that feeding of substitute protein diets did not induce any cholestatic hepatobiliary obstructions and that the low hepatic taurine level was one of the probable factors responsible for the occurrence of green liver in red sea bream fed substitute protein diets. 相似文献
30.