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51.
Radiocesium is an extremely harmful radionuclide because of its long half-life; it is important to reduce its transfer from contaminated soil into crops. Here we surveyed genetic variation for seed cesium (Cs) concentration in soybean mini-core collections representing large genetic diversity. The collections grown over 3 years in rotational paddy fields exhibited varying seed Cs concentrations with significant year-to-year correlations, although the phenotypic stability of Cs concentration was lower than that of the congeners potassium (K) and rubidium (Rb). Although Cs is supposedly accumulated in plants via the K transport system, there was no apparent relationship between Cs and K concentrations, whereas a clear positive correlation was observed between Cs and Rb concentrations. Cs and K concentrations in seed showed slightly positive and negative correlations, respectively, with days to flowering. We selected several high or low Cs accumulator candidates on the basis of the 3 years of seed concentration data. These two groups showed significantly different seed Cs concentrations in another field. The differences could not be explained by flowering time alone. These results suggest that genetic variation for seed Cs concentration is present in soybean germplasm and would be useful for breeding low Cs-accumulating varieties.  相似文献   
52.
S. Kato    S. Ishikawa    S. Imakawa    S. Komori    T. Mikami  Y. Shimamoto 《Plant Breeding》1993,111(2):162-165
Three apple (Malus×domestica) cultivars and 11 Malus accessions have been investigated by the probe hybridization method on their mitochondrial DNA (mtDNA). The gene probes used were: coxI, coxII, atpA, atp6, and atp9. Our results revealed enough variation to characterize ten mtDNA haplotypes among the Malus genotypes examined. The taxonomic and phylogenetic implications of mtDNA polymorphism are also discussed.  相似文献   
53.
Seventy-two accessions covering six varieties of Cucumis melo were characterized by using 35 morphological characters with emphasis on shelf-life, and the relationships between shelf-life and related characters was investigated. Principal component analysis (PCA) revealed that development period of plant and fruit, size of seed and fruit, shelf-life, stem hair, flesh juiciness, netting, abscission of peduncle, rapid yellowing of epidermis at maturity, Brix value, and color of flesh and epidermis etc. were the principal characters to discriminate melon accessions examined in the present study. According to the scatter diagram, vars. acidulusand makuwa, both of which belong to the Oriental melon, are closely related because of their short growth duration, small seed, thin pericarp and poor shelf-life, while American cantaloupe (var.reticulatus) and European cantaloupe (var. cantalupensis) are rather closely related due to their climacteric fruit with orange flesh, slipped peduncle and rapid yellowing of epidermis at maturity, which is closely related with their shelf-life. PCA also indicated that var. saccharinus was closer to var. inodorus than to the other varieties, due to their requirement of long period for development, large size of seed and fruit, and half- or non-slipped peduncle. Shelf-life of melon fruit was significantly correlated with the following characters: quality of flesh, size of seed and fruit, abscission of peduncle, development periods of plant and fruit, rapid yellowing of epidermis at maturity, Brix value and color of flesh and epidermis. Accessions with good shelf-life were mostly found in vars. saccharinus and inodorus. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
54.
Arabinoglucuronoxylans (AGXs) isolated from the holocellulose of sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) contained one 4-O-methyl-d-glucopyranosyluronic acid (4-O-Me-d-GlcAp) residue per 6.2 d-xylopyranose (d-Xylp) residues and one 4-O-Me-d-GlcAp residue per 3.8 d-Xylp residues. These AGXs were subjected to partial acid hydrolysis. Analyses by size exclusion chromatography and electrospray-ionization mass spectroscopy of the neutral sugar fractions in the hydrolysates showed the presence of xylooligosaccharides having a degree of polymerization of 2-8 in addition to d-Xyl, suggesting that the AGXs from sugi and hinoki contained unsubstituted chains consisting of at least eight d-Xyl residues. The acidic sugars in the hydrolysates were separated into two series of aldouronic acids composed of 4-O-Me-d-GlcAp and d-Xylp by ion-exchange chromatography. The first series included aldouronic acids from aldobiouronic acid (4-O-Me-d-GlcAp-Xyl) to aldopentaouronic acids (4-O-Me-d-GlcAp-Xyl4). The second series were aldouronic acids composed of two 4-O-Me-d-GlcAp residues and 2-4 d-Xyl residues. In these acidic sugars, the uronic acid side chains were located on two contiguous d-Xyl residues. These facts indicated that AGXs from sugi and hinoki had a structural unit containing two 4-O-Me-d-GlcAp residues on two contiguous d-Xyl residues as well as AGXs from spruce and larch.  相似文献   
55.
Antioxidative compounds from the outer scales of onion   总被引:2,自引:0,他引:2  
Antioxidative compounds were isolated from the methanol extract of dry outer scales of onion (Allium cepa L.). Nine phenolic compounds (1-9) were finally obtained by reversed-phase high-performance liquid chromatography, and their structures were elucidated by NMR and mass spectrometry analyses. They were the six known compounds, protocatechuic acid (1), 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2), quercetin 4'-O-beta-D-glucopyranoside (3), quercetin (5), 4'-O-beta-d-glucopyranoside of quercetin dimer (7), and quercetin dimer (8), and three novel compounds, condensation products of quercetin with protocatechuic acid (4), adduct of quercetin with quercetin 4'-O-beta-D-glucopyranoside (6), and quercetin trimer (9). These phenolic compounds were tested for their antioxidant properties using autoxidation of methyl linoleate in bulk phase or free radical initiated peroxidation of soybean phosphatidylcholine in liposomes. The flavonoid compounds having o-dihydroxy substituent in the B-ring were shown to be effective antioxidants against nonenzymic lipid peroxidation.  相似文献   
56.
Antioxidative compounds were isolated from the methanol extract of fresh rhizome of smaller galanga (Alpinia officinarum Hance). Seven phenylpropanoids (1-7) were finally obtained by reversed-phase HPLC, and their structures were elucidated by MS and NMR analyses. They comprised the two known compounds, (E)-p-coumaryl alcohol gamma-O-methyl ether (1) and (E)-p-coumaryl alcohol (6), and the five novel compounds, stereoisomers of (4E)-1,5-bis(4-hydroxyphenyl)-1-methoxy-2-(methoxymethyl)-4-pentene (2a and 2b), stereoisomers of (4E)-1,5-bis(4-hydroxyphenyl)-1-ethoxy-2-(methoxymethyl)-4-pentene (3a and 3b), (4E)-1,5-bis(4-hydroxyphenyl)-1-[(2E)-3-(4-acetoxyphenyl)-2-propenoxy]-2-(methoxymethyl)-4-pentene (4), (4E)-1,5-bis(4-hydroxyphenyl)-2-(methoxymethyl)-4-penten-1-ol (5), and (4E)-1,5-bis(4-hydroxyphenyl)-2-(hydroxymethyl)-4-penten-1-ol (7). Compounds 1-7 were detected for the first time as constituents of galanga rhizomes and exhibited antioxidative activities against the autoxidation of methyl linoleate in bulk phase.  相似文献   
57.
Spelt wheat, Triticum spelta L., has been proved to be rich-sources of useful genes for tolerance to biotic and abiotic stress, and grain quality. But this crop plant has some undesirable traits including glume tenacity and brittle rachis. Free-threshing and reduced fragility of rachis are very important traits for cultivation. The objectives in the present study were to investigate genetic variation of rachis fragility in a wide range of spelt accessions, to examine its genetic segregation pattern, and to clarify if rachis fragility is associated with dosage of chromosome 5A in aneuploid lines of bread wheat. The results demonstrated that spelt germplasm contains a wide range of rachis toughness, and thus selection of spelt wheat with desirable characteristics combined with an appropriate level of tough rachis would be possible. Spike morphology in the F2 plants was segregated into the three types, square-headed, speltoid, and compactoid. The F2 plants with compactoid spikes had the most brittle rachis, followed by the speltoid and square-headed spike F2 plants. Rachis fragility in bread wheat also had genetic variation and was associated with dosage of chromosome 5A.  相似文献   
58.
The precipitation chemistry in northern Japan, especially Hokkaido, has been investigated since 1982. This area has often been found to have high concentrations of alkaline road dust (asphalt dust) in the air, caused by the use of studded tires during the winter. It is well known that the composition of precipitation in these areas is often dominated by asphalt dust including calcium bicarbonate. However, recently the concentration of asphalt dust in the air has decreased owing to a ban on the use of studded tires. Simultaneously, in precipitation, the lowering of pH values and the increase of hydrogen ion depositions have been occurring owing to the decrease of non-sea-salt calcium ions (nss-Ca2+) concentrations and depositions derived from asphalt dust. In addition, we found that a decrease of nss-Ca2+ firstly leads to a decrease of bicarbonate ions (HCO3 ?), the counter ion to nss-Ca2+ in asphalt dust. Therefore, the increase of H+ concentrations and depositions was great in comparison with the decrease of nss-Ca2+ concentrations and depositions in areas where the HCO3 ?concentrations, varied by pH, and depositions had been low. Furthermore, this variation was mainly observed in the ionic composition of snow cover and snowfall at sites along the Japan Sea in northern Japan during winter. In this area, the Acid Shock effect may become a serious problem from the decline of pH values in melting snow. Moreover, we found that ammonium ions and non-sea-salt sulfate ions depositions have also been decreasing in response to a decrease of nss-Ca2+ depositions, derived from asphalt dust. It seems that this phenomenon is caused by the decrease of asphalt dust concentrations in the air.  相似文献   
59.
60.
We have investigated the inhibitory effects of polyphenols from natural products, such as green tea, bilberry, grape, ginkgo, and apple, on rainbow trout gelatinase activities. Gelatinases from the skin, muscle, and blood of rainbow trout contained serine proteinase, metalloproteinase, and other proteinase activities as measured by gelatin zymography. The polyphenols of green tea caused the strong inhibition of some gelatinase activities when compared with those of the other products. This inhibition was quite similar to that of metalloproteinase by ethylenediaminetetraacetic acid, suggesting that the effects of green tea polyphenols on proteinase activities are specific for metalloproteinases. The major catechins of green tea polyphenols were then separated and identified by reverse-phase chromatography to be (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin, (-)-epicatechin gallate, and (-)-epicatechin. The effects of these catechins on gelatinase activities were examined; the most potent inhibitor of metalloproteinase activities was found to be EGCG. These results have indicated that green tea polyphenols including EGCG are useful for regulating metalloproteinase activities of fish meat.  相似文献   
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