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101.
Surveillance and characterization of Newcastle disease viruses isolated from northern pintail (Anas acuta) in Japan during 2006-09 总被引:1,自引:0,他引:1
Ruenphet S Jahangir A Shoham D Morikawa K Miyoshi Y Hanawa E Okamura M Nakamura M Takehara K 《Avian diseases》2011,55(2):230-235
A total of 38 Newcastle disease virus (NDV) isolates were obtained from 6060 fecal samples from northern pintail (Anas acuta) ducks collected in the Tohoku district in Japan during 2006-09. One isolate from each sampling location and date was selected for a total of 38 isolates, then 15 of these were characterized for their pathogenicity by mean death time of minimum lethal dose (MDT/MLD) using chicken embryos and by plaque formation on chicken embryo fibroblasts. Furthermore, nine isolates were randomly selected from these 15 isolates, and the fusion protein genes were sequenced to characterize amino acid sequences around the cleavage site. All 15 were confirmed to be nonvirulent by MDT/MLD test, and nine isolates were also confirmed as nonvirulent by the cleavage site of the fusion protein 112G/E-K/R-Q-G/E-R*L117 that was specific for nonvirulent NDVs. The characteristics of nine isolates identified by phylogenic analysis of the fusion protein gene indicated that the isolates belong to genotype I or II. In addition, we also isolated 68 avian influenza viruses and 28 other hemagglutinating viruses. Our data indicate that northern pintails are subclinically infected by, perpetuate, and distribute NDV along with different subtypes of avian influenza viruses and other hemagglutinating viruses during their migrations across vast areas over the Northern Hemisphere to Japan. 相似文献
102.
Umeki S Suzuki R Shimojima M Ema Y Yanase T Iwata H Okuda M Mizuno T 《Veterinary immunology and immunopathology》2011,142(1-2):119-125
Thirteen different monoclonal antibodies against canine P-selectin glycoprotein ligand-1 (cPSGL-1) were obtained by immunization of rats with cells of a canine lymphoma cell line (Ema). O-sialoglycoprotein endopeptidase treatment of Ema cells showed that all of these antibodies recognized O-glycosylated peptides of canine PSGL-1. Experiments using deletion or point mutants of cPSGL-1 indicated that these antibodies could be categorized into several groups based on their cPSGL-1 recognition characteristics. These anti-cPSGL-1 monoclonal antibodies will be useful for analysis of the canine P-selectin and PSGL-1 system. 相似文献
103.
The interlayered hydroxy-aluminum of a chlorite-smectite intergrade in a dark-red soil derived from a pyroxene andesite altered by hydrothermal action was extracted easily by boiling treatments using both sodium-citrate and ammonium-fluoride solutions. Moreover, this interlayered aluminum was released partially by using a dithionite-citrate-bicarbonate system and an acid ammonium-oxalate solution which were prepared originally for removing the coexistent sesquioxides from soils. 相似文献
104.
Keiichi Murakami Masayuki Hara Takuya Kondo Yohey Hashimoto 《Soil Science and Plant Nutrition》2013,59(5):705-709
Microbial mineralization of urea and uric acid in poultry litter can lead to loss of nitrogen (N) content and its value as a fertilizer. To minimize the loss of N in the composting processes, controlling the water content in litters is a key to reduce the mineralization processes of N compounds. The N content of litter may be influenced by diets, hen age and the type of poultry houses used. The objectives of the present study were i) to determine the relationship between the water content and the decomposition rate of uric acid in poultry litter and ii) to investigate the effect of hen age and crude protein (CP) percentages in diets on the N content of poultry litter. A layer feeding trial was conducted in two poultry farms with windowless and open-floor houses. An incubation study of poultry litter was performed under different levels of water content. Our study found that the diet CP percentage (16.5–18%) and the growth stage of laying hens did not have a significant effect on the amount of total N (52–56?g?kg?1) and uric acid-N (26–31g?kg?1) in fresh litters. At the 7th day of litter incubation study, the concentration of uric acid-N was 22 g kg?1 in litters with a water content of 35%, whereas it further decreased to less than 1.3 g kg?1 in litters with a water content of 55% and higher levels. The decomposition rate of uric acid-N in litter was 0.3–3.1g?kg?1?day?1 in the windowless house and 3.1–7.1g?kg?1?day?1 in the open-floor house. Decomposition of uric acid in litters was positively correlated to the litter moisture content that is controlled to be lower in windowless houses (40–50%) than in open-floor houses (55–80%) during the composting period. Our study suggests that the use of windowless houses for layer chicken production is effective for producing poultry manure with a high N content. 相似文献
105.
Yasuo Kitagawa 《Soil Science and Plant Nutrition》2013,59(4):321-324
Many scientists have attempted to discern the chemical composition and the structure of allophane (2, 4–6). Yoshinaga (7) presented the chemical composition of eighteen samples of pure allophane in detail, and concluded as follows: All samples consisted principally of silica, alumina, and water. The silica-alumina molecular ratio ranged from about 1.3 to 2. Molecular ratios of ignition loss (+H20) and total water (±H2O) to alumina were nearly constant, with the averages about 2.5 and 5.7, respectively. The chemical composition of soil allophane fell into a relatively narrow range, and the change in the percentage composition of the three major elements had a regularity. 相似文献
106.
Effect of Addition of Al Hydroxides on Changes in Dispersibility and Charge Characteristics of Soils
Katsuhiko Itami Yasuo Kitagawa Kazutake Kyuma Takashi Kosaki 《Soil Science and Plant Nutrition》2013,59(3):627-635
Using a soil from a newly reclaimed area where high dispersibility of fine particles had led to poor physical properties in the field, changes in dispersibility and charge characteristics after artificial precipitation of Al hydroxides onto the soil were investigated. Al hydroxides were precipitated by neutralization with NaOH of an acidic A1C13 solution in which the soil samples were placed. When the titration rates were changed, no significant differences in dispersibility were observed in the resultant soils. In the systems with the addition of 2 g kg-1 or less of A1(OH)3, dispersion ratios of clays were almost identical with those of blank samples although the specific surface areas were reduced. In the systems with 5 g kg-1 or more of A1(OH)3, considerable effects of Al hydroxides on reduction of clay dispersibility were recognized (e.g. 10 g kg-1 addition yielded less than one-third of the original ratio of the clay dispersion). A slightly larger decrease in dispersion was observed by the addition of 15 g kg-1 or more. As the amount of added Al increased, the amount of negative charges of the soil decreased while that of positive charges increased. The charge characteristics of the system with the addition of 20 g kg-1 of A1(OH)3 were closer to those of the adjacent forest soil which was characterized by a very low dispersibility. It was inferred that added Al hydroxides polymerized to form Al polycation species that were not readily exchangeable, neutralizing negative charges of clays, and acting as interparticle bonding between the clays. On the other hand, forest soils were considered to have acquired a physical stability against the dispersion of fine particles as free Al oxides had been accumulated in the process of natural weathering. It was concluded that charge characteristics primarily determined the dispersion and flocculation behavior of soils and that Al hydroxides were important modifiers of charge characteristics of soils. 相似文献
107.
Viscosity and molecular weight of particle size fractions obtained from an Andosol humic acid (HA) were determined. Viscosity was determined both in solutions with and without the addition of 0.1 M NaCl (Cs 0.1 and Cs 0, respectively) at pH 7.0. Polyelectrolytic character was observed in the particle size fractions based on the changes in the concentration dependence of reduced viscosity with NaCI concentrations. The use of a Cs 0.1 solution was suitable for the determination of the values of intrinsic viscosity ([η]) of the particle size fractions. The [η] value increased with increasing weight average molecular weight ( M w) determined by gel permeation chromatography (GPC), and ranged from 4.3 to 12.9 X 10-3 (L g-1) in the Cs 0 solution and from 3.5 to 6.6 × 10-3 (L g-1) in the Cs 0.1 solution. A linear relationship between [η] in the Cs 0.1 solution and M w on a logarithmic scale, which was similar to the MarkHouwink equation, was observed. The value of the constant a calculated from the relationship, which reflected the polymer morphology, was 0.75 in the Cs 0.1 solution, and it corresponded to a polymer with flexible chains. 相似文献
108.
Yaguang Zhou Masami Fushitani Keiichi Sato Masayuki Ozawa 《Journal of Wood Science》2000,46(6):423-430
This study examined the bending creep behavior of hot-pressed wood during cyclic moisture changes. Sugi (Cryptomerica japonica D. Don) specimens were pressed in the radial direction under six combinations of nominal compressive strain (33% and 50%) and press temperatures (140°C, 170°C, 200°C). Creep tests were conducted at 20°C with three cyclic relative humidity changes between 65% and 95% under 25% of short-breaking stress. The effect of moisture content (MC) change on elastic compliance and mechanosorptive (MS) compliance was investigated. The relation between MS compliance and thickness swelling was studied. The results indicated that total compliance increased over the history of cyclic moisture changes; and its behavior was closely related to the changes in MC and thickness swelling. The total compliance increased during adsorption and decreased during desorption. Elastic compliance increased linearly with MC and was dependent on press temperature and compression. With increasing MC change, MS compliance increased during adsorption and decreased during desorption. The first adsorption led to greater MS compliance than did the subsequent adsorption with the same amount of MC change. In general, the elastic parameterK
E and the MS parameterK
Mincreased with compression and decreased as the press temperature increased. The MS parameterK
M was apparently greater than the elastic parameterK
E. The MS parameterK
M increased with swelling coefficient KSW of the hot-pressed specimen during adsorption and decreased with an increasing shrinkage coefficientK
SH during desorption. 相似文献
109.
Ishioka K Hosoya K Kitagawa H Shibata H Honjoh T Kimura K Saito M 《Research in veterinary science》2007,82(1):11-15
Leptin is a cytokine produced by adipocytes, and plays a key role in the regulation of energy balance. In the present study, we measured plasma leptin concentrations of 166 normal and obese dogs visiting veterinary practices, and clarified the influence of age, gender and breed on plasma leptin levels in dogs. Leptin levels were higher in the dogs with higher body condition scores. There was no noticeable influence of age, gender and breed, but those in optimal puppies and obese Miniature Dachshund tended to be lower than those in corresponding groups. We conclude that plasma leptin is a reliable marker of adiposity in dogs regardless of age, gender and breed variations, and thereby useful as a blood biochemistry test for health examinations and treatment of obesity. 相似文献
110.
Yoshinobu Uemoto Masayuki Takeda Atushi Ogino Kazuhito Kurogi Shinichro Ogawa Masahiro Satoh Fuminori Terada 《Animal Science Journal》2020,91(1)
The objectives of this study were to estimate genetic parameters and to perform a genome‐wide association study (GWAS) for predicted methane‐related traits in Japanese Black steers. The methane production and yield traits were predicted using on‐farm measurable traits, such as dry matter intake and average daily gain. A total of 4,578 Japanese Black steers, which were progenies of 362 sires genotyped with imputed 551,995 single nucleotide polymorphisms (SNPs), had phenotypes of predicted methane‐related traits during the total fattening period (52 weeks). For the estimation of genetic parameters, the estimated heritabilities were moderate (ranged from 0.57 to 0.60). In addition, the estimated genetic correlations of methane production traits with most of carcass traits and feed‐efficiency traits were unfavorable, but those of methane yield traits were favorable or low. For the GWAS, no genome‐wide significant SNP was detected, but a total of four quantitative trait locus (QTL) regions that explained more than 5.0% of genetic variance were localized on the genome, and some candidate genes associated with growth and feed‐efficiency traits were located on the regions. Our results suggest that the predicted methane‐related traits are heritable and some QTL regions for the traits are localized on the genome in Japanese Black steers. 相似文献