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91.
Marek's disease virus serotype 1 (MDV-1) strains cause malignant lymphoma in chickens. MDV-1 has been previously reported to be widespread in white-fronted geese (Anser albifrons); however, the prevalence of MDV-1 in other wild birds has not been determined. In this study, we investigated the prevalence of MDV-1 in various wild birds in Hokkaido, Japan. The MDV-1 genome was widespread in geese and ducks, but was not detected in other birds. MDV-1 was detected in both sedentary and migratory species. These results suggest that, in Japan, MDV-1 is widespread in wild goose and duck populations, and that resident ducks may be significant carriers and reservoirs of MDV-1.  相似文献   
92.
The volatile components of Citrus sphaerocarpa Tanaka (Kabosu) cold-pressed peel oil were investigated by chemical and sensory analyses. Monoterpene hydrocarbons (more than 94.6%) were predominant in Kabosu peel oil, with limonene and myrcene accounting for the major proportions (70.5% and 20.2%, respectively). The Kabosu oxygenated fraction was characterized by quantitative abundance in aldehydes and a relatively wide variety of alcohols. The weight percentages of aldehydes, alcohols, and esters in Kabosu cold-pressed oil were 1.3%, 0.1%, and 0.1%, respectively. Aroma extract dilution analysis was employed for determination of the odors of Kabosu volatile components, flavor dilution factors, and relative flavor activities. Gas chromatography/olfactometry using Kabosu cold-pressed oil and its oxygenated fraction completed by a chiral analysis revealed that (R)-(+)-citronellal is a characteristic element of Kabosu peel oil odor. Careful sniff testing demonstrated that aqueous solutions of both 0.25% and 0.016% (R)-(+)-citronellal gave an odor similar to that of Kabosu.  相似文献   
93.
To estimate the metabolic profile of trans-permethrin in humans, a comparison of the in vitro metabolism of trans-permethrin in humans and rats was conducted using hepatic microsomes, and cytochrome P450 and UDP-glucuronyltransferase isoforms, which catalyze the metabolism of 3-phenoxybenzyl alcohol (PBalc) and 3-phenoxybenzoic acid (PBacid), respectively. In humans and rats, the major metabolic reaction of trans-permethrin in microsomal incubations was the cleavage of ester linkage to give PBalc, followed by oxidation to 4'-OH-PBalc, 4'-OH-PBacid, and PBacid. As to 4'-hydroxylation of PBalc, several CYPs were able to catalyze the reaction, and CYP2E1 was identified as a predominant isoform. PBacid and its conjugates (glucuronide and glycine) are major urinary metabolites of trans-permethrin in mammals. PBacid is also a metabolite of several pyrethroids, and has been used as a biomarker of human exposure to pyrethroids. Our study indicated that there was no difference in glucuronyltransferase activity of PBacid between humans and rats, and that only UGT1A9 can catalyze the glucuronidation of PBacid among human UGTs. Some UGT1A9 variants are known to have poor glucuronidation activity. From these results, it was assumed that deficiency or polymorphism of UGT1A9 might affect the profile of PBacid and its conjugates in urine collected from persons exposed to trans-permethrin or other pyrethroids. These results are helpful for understanding the metabolism of trans-permethrin in humans and determining methods for quantification of target analytes for assessment of human exposure to trans-permethrin and other pyrethroids that give PBacid and its conjugates as urinary metabolites.  相似文献   
94.
Complete sequences of transcribed spacers and introns from the trnT trnF region of chloroplast DNA (cp DNA) were generated from Musaceae species to establish the phylogenetic relationships among 3 species of Ensete including the economically important Ensete ventricosum (Welw.) Cheesman and 13 species of Musa. Parsimony analysis and pair wise distance data produced a single tree, with Ensete and Musa as clearly distinguished clades. Six Musa and three Ensete clades were generated. The topology of these clades did not change when the data were split into spacers and introns, although the split resulted in poor bootstrap support. Removing a hotspot from the entire data set improved clade support. The clades produced are discussed with reference to existing taxonomic and phylogenetic treatments. In contrast to previous suggestions, most of the Rhodochlamys species that we investigated clustered together with strong support establishing their distinctiveness from the Musa species studied. Ensete glaucum (Roxb.) Cheesman and Musa beccartii Simmonds appear to represent ancestral forms of Ensete and Musa, respectively for the presently studied species, and both genera have a common ancestor that is yet to be established. Our data also show that E. ventricosum cannot be reduced to E. glaucum, nor can E. gilleti (De Wild.) Cheesman be reduced to E. ventricosum, as some authorities have suggested. Ensete gilleti or a species very close to it appears to be the ancestral species of E. ventricosum.  相似文献   
95.
Integration of previously developed Allium cepa linkage maps requires the availability of anchor markers for each of the eight chromosomes of shallot (A. cepa L. common group Aggregatum). To this end, eight RAPD markers originating from our previous research were converted into SCAR markers via cloning and sequencing of RAPD amplicons and designing of 24-mer oligonucleotide primers. Of the eight pairs of SCAR primers, seven resulted in the amplification of single bands of the original RAPDs, and the remaining primer set amplified an additional band. The results of Southern hybridization using RAPD amplicons from genomic DNA of Japanese bunching onion (Allium fistulosum L.)—shallot monosomic addition lines indicated that five SCAR markers were single shallot chromosome-specific markers and were not detected in genomic DNA of A. fistulosum. The eight SCAR primer pairs were applied to other Allium species and exhibited three types of amplification profiles, namely RAPD amplicons observed only in shallot, in shallot and Allium vavilovii, and in several Allium species. A mapping study using 65 F2 plants generated by the selfing of one interspecific cross A. cepa × Allium roylei individual integrated the SCAR marker SAOE17500 into chromosome 5 as expected. The results of the present study show that the eight SCAR primer sets specific to shallot can facilitate the mapping in A. cepa and can also serve as anchor points between maps of different Allium species.  相似文献   
96.
Peel yellowing is a major postharvest problem of lime fruit. Research was conducted to control peel yellowing by UV-B irradiation. Mature green lime fruit were irradiated with UV-B doses at 0 (control), 8.8, and 13.2 kJ m?2 and then stored at 25 °C in darkness. UV-B treatment at 8.8 kJ m?2 efficiently delayed the decrease of chlorophyll content. A high level of chlorophyllide a accumulated in mature green fruit and then gradually decreased with the progress of peel yellowing. The chlorophyllide a level was higher in 8.8 kJ m?2 UV-B-treated fruit than it was in the controls. The pheophorbide a level declined in lime fruit treated with 8.8 kJ m?2 UV-B, especially during the development of yellowing. In addition, the pheophytin a level increased by 8.8 kJ m?2 UV-B treatment at the late period of storage. We concluded that UV-B treatment effectively suppressed chlorophyll degradation in mature green lime during storage, which suggests that UV-B irradiation is a usable method for prolonging the postharvest life of lime fruit.  相似文献   
97.
Abstract

The carbon (C) budget of managed grassland in a cool-temperate region of Japan was estimated using a combination of eddy covariance and the biometric method for five years, to evaluate the effect of manure application. Chemical fertilizer was applied to the fertilizer (F) plot at a rate of 79 ± 20 kg N ha?1 yr?1. In the manure (M) plot, dairy cattle manure was applied at a rate of 10 Mg fresh matter ha?1 yr?1 (1923 ± 407 kg C ha?1 yr?1, 159 ± 68 kg N ha?1 yr?1). There was no significant difference in seasonal gross primary production (GPP) and harvest between the treatment plots, indicating that both fertilizer and manure can increase the biomass production. Annual net ecosystem production (NEP) and ecosystem respiration (RE) was significantly different between the treatment plots. The difference in RE, and between M and F plots approximates heterotrophic respiration of manure (RHm), which ranged from 0.9 to 1.3 Mg C ha?1 yr?1. Average annual RHm was 1.1 ± 0.4 Mg C ha?1 yr?1, and accounted for 56% of the total amount of applied manure C. The annual net biome production (NBP) in the M plot (from 0.0 to 1.5 Mg C ha?1 yr?1) was significantly higher than in the F plot (?1.4 to 0.5 Mg C ha?1 yr?1). The long-term effect of manure application combined with chemical fertilizer did not reduce grass production compared with chemical fertilizer only; however, manure application decreased the NEP throughout manure decomposition, and long-term manure application enhanced the NBP.  相似文献   
98.
Interspecific protoplast fusion between two monokaryotic strains (a methionine auxotrophic and chloramphenicol-resistant Pleurotus ostreatus strain and a wild-type strain of Pleurotus pulmonarius) was carried out to introduce mitochondrial DNA (mtDNA) from P. ostreatus into P. pulmonarius. Because mycelial colonies regenerated on minimum medium containing chloramphenicol only after the treatment of protoplast electrofusion, the regenerants were regarded as protoplast fusants. The fusants isolated from regenerated colonies were uninucleate, and their resistance of chloramphenicol seemed to be a stable trait. The fusants mated with P. pulmonarius but not with P. ostreatus, and showed almost identical random amplified polymorphic DNA (RAPD) patterns to that of the parental P. pulmonarius monokaryon. The sizes of mitochondrial genomes were estimated to be 81.5 kb for P. ostreatus monokaryon, 54.9 kb for P. pulmonarius monokaryon, and 84.5 or 86.0 kb for the fusants. BamHI and EcoRI digest patterns of the fusant mtDNAs were almost the same as the parental P. ostreatus monokaryon. From the above results, the fusants seemed to carry nuclei derived from the monokaryon of P. pulmonarius and mtDNA including the chloramphenicol-resistance gene from the P. ostreatus monokaryon, suggesting that the P. ostreatus mtDNA had been introduced into P. pulmonarius cells by interspecific protoplast fusion. Contribution No. 383 of the Tottori Mycological Institute  相似文献   
99.
The canine immune system undergoes continuous remodeling with advancing age. We measured the Th1/Th2 balance in peripheral blood lymphocytes (PBLs) obtained from 23 Beagles ranging in age from 0.5 to 11.8 years by flow cytometric analysis using intracellular cytokine staining. The percentage of CD4 cells producing interferon-gamma (Th1) increased with age. The percentage of CD4 cells producing interleukin-4 (Th2) increased but much less so. In conclusion, we demonstrated that the Th1/Th2 balance in canine peripheral blood could be measured by this flow cytometry technique and the Th1/Th2 balance inclined to dominance of the Th1 subpopulation in PBLs as the dog matured.  相似文献   
100.
Parameters of heart rate variability would explain changes in heart rate during the disease status in cows and to evaluate whether such changes might provide a more sensitive and quantitative indicator of these conditions than crude indices. For this purpose, we recorded electrocardiograms for 24 hr using a Holter-type electrocardiograph and applied power spectral analysis of heart rate variability in both five clinically healthy and four hospitalized cows. The significant findings of the current investigation were that the diurnal variations of autonomic nervous function are abolished in cows that are sick. This abnormal rhythm was induced by predominant parasympathetic inhibition in these cows. Therefore, the heart rate variability may be a useful indicator of sickness condition in cows.  相似文献   
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