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81.
Lunasin and Bowman-Birk protease inhibitor (BBI) are two soybean peptides to which health-promoting properties have been attributed. Concentrations of these peptides were determined in skim fractions produced by enzyme-assisted aqueous extraction processing (EAEP) of extruded full-fat soybean flakes (an alternative to extracting oil from soybeans with hexane) and compared with similar extracts from hexane-defatted soybean meal. Oil and protein were extracted by using countercurrent two-stage EAEP of soybeans at 1:6 solids-to-liquid ratio, 50 °C, pH 9.0, and 120 rpm for 1 h. Protein-rich skim fractions were produced from extruded full-fat soybean flakes using different enzyme strategies in EAEP: 0.5% protease (wt/g extruded flakes) used in both extraction stages; 0.5% protease used only in the second extraction stage; no enzyme used in either extraction stage. Countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes was used as a control. Protein extraction yields increased from 66% to 89-96% when using countercurrent two-stage EAEP with extruded full-fat flakes compared to 85% when using countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes. Extruding full-fat soybean flakes reduced BBI activity. Enzymatic hydrolysis reduced BBI contents of EAEP skims. Lunasin, however, was more resistant to both enzymatic hydrolysis and heat denaturation. Although using enzymes in both EAEP extraction stages yielded the highest protein and oil extractions, reducing enzyme use to only the second stage preserved much of the BBI and Lunasin.  相似文献   
82.
14C]-aflatoxin B1 metabolism in lactating goats and rats   总被引:1,自引:0,他引:1  
Four dairy goats in the second to third month of lactation were administered [14C]-Aflatoxin B1 ( [14C]-AFB1). Two goats were dosed intravenously (iv) with 130 muCi (182 muCi/mumol) and two were dosed orally with 196 muCi (256 muCi/mumol). Urine, milk and feces were collected for 120 h after [14C]-AFB1 administration. Recoveries (average of two animals) of 14C in urine, milk and feces were, respectively; 22.7, .97 and 65% (iv dose) and 30.9, 1.05 and 52.3% (oral dose). Aflatoxin M1 (AFM1) was found in milk in the highest concentration. Aflatoxin Q1 (AFQ1) and aflatoxicol (AFL) were found in trace quantities in milk of animals administered the oral dose. In general, AFM1 could account for the majority of dicholromethane-soluble 14C. Liver contained 7.3 and 4.9% of the dose after 120 h for the iv and oral doses respectively. Kidney, heart, lung and spleen all contained .1% or less of the dose at 120 h. Muscle contained .48% of the dose at 120 h from the goats administered [14C]-AFB1 orally. There was no detectable radioactivity in the fat of any goat at 120 h. Six lactating Sprague-Dawley rats with 12 nursing pups were used for comparison of ruminants and simple-stomached animals. Rats were administered 2 muCi of [14C]-AFB1 (125 muCi/mumol) iv (three animals) and orally (three animals). Mean recovery of 14C in urine, mammary plus milk and feces were, respectively; 9.5, 2.0 and 60.7% (iv) and 8.8, 2.6 and 65.0% (orally).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
83.
Bovine ephemeral fever in Taiwan (2001-2002)   总被引:3,自引:0,他引:3  
Bovine ephemeral fever (BEF), a vector-borne disease of cattle, is caused by the Ephemerovirus of the family Rhabdoviridae. In the past 40 years, Taiwan has had seven BEF epizootics, and we have previously reported the first five. This study summarizes the 2001 and 2002 epizootics; conducted case-control serologic studies on 10 herds involved in the 2001 epizootic; determined whether the recent BEF viruses have varied significantly; and discusses the relationship between epizootic patterns and possible variant BEF viruses. For mature cows that had received at least 2 doses of vaccine before the study, a negative correlation between the prevaccinated (the 3rd dose and after) serum neutralization antibody (SNA) titers and their postvaccinated peak rates was found. When prevaccinated SNA levels were at < or = 32, their postvaccinated SNA levels increased significantly faster (P<0.01) than for those at > or = 32. The glycoprotein gene of isolates from 1999, 2001, and 2002 had a 99.2-99.9% homology, without consistent amino acid variations in the neutralization sites. Phylogenetic analysis of Taiwanese isolates revealed 2 distinct clusters, the 1983-1989 and 1996-2002 isolates. Cross-neutralization tests confirmed the glycoprotein gene sequence analysis results. In conclusion, annual boosters at SNA levels > 32, at more than 2 doses, or at intervals shorter than 6 months are not advisable. The occurrence of frequent small epizootics implies the dominance of BEF virus over host immunity, but not a variant virus.  相似文献   
84.
Multiple novel vegetable oil-based polyols were synthesized from the reaction-addition to epoxidized soybean oil (ESBO) by a series of acid acyl moieties derived from vegetable oils. The acid acyl moieties were linoleic acid (LA), ricinoleic acid (RC), ricinoleic acid estolide (RC estolide) and hydrolyzed bodied soybean oil (HBSBO). LA and RC were commercially available but RC estolide and HBSBO were synthesized by enzymatic catalytic reactions. In the reaction-addition, ESBO was heated with the acid acyl moieties at 170 °C, atmospheric pressure without any catalyst and solvent. The synthesized vegetable oil-based polyols had acid numbers less than 10 (mg KOH/g), hydroxy numbers of 82–152 (mg KOH/g), and hydroxyl equivalent weights of 370–680. The polyols made from RC estolide and HBSBO had improved numbers of OH equivalent weight comparing to the numbers from alkoxyl hydroxyl soybean oil which is widely used commercial soy-based polyols.  相似文献   
85.
Feline infectious peritonitis (FIP) is an immune-mediated, highly lethal disease caused by feline coronavirus (FCoV) infection. Currently, no protective vaccine or effective treatment for the disease is available. Studies have found that some cats survive the challenge of virulent FCoV isolates. Since cellular immunity is thought to be critical in preventing FIP and because diseased cats often show a significant decrease in interferon-γ (IFN-γ) production, we investigated whether single nucleotide polymorphisms (SNP) in the feline IFN-γ gene (fIFNG) are associated with the outcome of infection. A total of 82 asymptomatic and 63 FIP cats were analyzed, and 16 SNP were identified in intron 1 of fIFNG. Among these SNP, the fFING + 428 T allele was shown to be a FIP-resistant allele (p = 0.03), and the heterozygous genotypes 01C/T and +408C/T were found to be FIP-susceptible factors (p = 0.004). Furthermore, an fIFNG + 428 resistant allele also showed a clear correlation with the plasma level of IFN-γ in FIP cats. For the identification of these three FIP-related SNP, genotyping methods were established using amplification refractory mutation system PCR (ARMS-PCR) and restriction fragment length polymorphisms (RFLP), and the different genotypes could easily be identified without sequencing. The identification of additional FIP-related SNP will allow the selection of resistant cats and decrease the morbidity of the cat population to FIP.  相似文献   
86.
The effect of dietary N‐carbamylglutamate (NCG) supplementation during the entire gestation on reproductive performance of gilts was determined. At the initial day of gestation, forty‐five cross‐bred (Landrace × Large white) gilts were randomly assigned to five groups receiving a basal diet (control group) and basal diet supplemented with 0.05%, 0.10%, 0.15% and 0.20% NCG until parturition, respectively. At parturition, total litter size, live litter size and rate of stillbirth were not markedly affected by NCG supplementation. However, gilts in 0.05% NCG‐supplemented group had more pigs born alive than gilts in control group (+1.11 pigs, p = 0.12), and live litter weight was increased (+12.13–19.17%, p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups relative to control group. And also, average birthweight of piglets born alive was higher (+6.57%, p < 0.05) in 0.05% NCG‐supplemented group than in control group. Furthermore, on days 30, 60, 90 and 110 of gestation, concentrations of arginine and ornithine in plasma were higher (p < 0.05) in 0.05%, 0.10%, 0.15% and 0.20% NCG‐supplemented groups than in control group, respectively. In addition, the chorioallantois gene expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor A (VEGF‐A), placental growth factor (PLGF) and angiopoietin‐2 (ANG‐2) was all increased (p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups than in control group. In conclusion, dietary supplementation with 500 mg/kg NCG during the entire gestation significantly improves pregnancy outcomes in gilts, which may be associated with the improved concentrations of arginine in plasma and placental angiogenic factors gene expression of gilts.  相似文献   
87.
In this study, we investigated parthenogenetic induction of canine oocytes by electrical stimulation following Ca-EDTA treatment. Oocyte maturation, parthenogenetic development, and cleavage rate in canine after various electrical stimulations (1.5, 1.8, 2.1 kV/cm) for 50 μs with single DC pulse following 1 mM Ca-EDTA treatment were investigated. In oocyte activated electrically at the voltage of 1.5 kV/cm after 1 mM Ca-EDTA treatment, the rate of pronucleus and two-cell was 4.1% and 2.7%, respectively. Although electrical stimulation could parthenogenetically induce immature oocyte to cleavage stage, degeneration rate in all experimental groups was more than 60%. This means that electrical stimulation after Ca-EDTA treatment could cause canine oocytes to be degenerated. However, two-cell in canine oocyte by parthenogenesis was for the first time induced. Therefore, we suggested that electrical stimulation for canine oocytes could induce parthenogenetically early embryonic cleavage. This result can be used as a basic data for parthenogenesis study in canine. Also, to perform more developed embryonic development, further study to parthenogenesis in canine need to be developed.  相似文献   
88.
Comets are icy bodies that sublimate and become active when close to the Sun. They are believed to originate in two cold reservoirs beyond the orbit of Neptune: the Kuiper Belt (equilibrium temperatures of approximately 40 kelvin) and the Oort Cloud (approximately 10 kelvin). We present optical data showing the existence of a population of comets originating in a third reservoir: the main asteroid belt. The main-belt comets are unlike the Kuiper Belt and Oort Cloud comets in that they likely formed where they currently reside and may be collisionally activated. The existence of the main-belt comets lends new support to the idea that main-belt objects could be a major source of terrestrial water.  相似文献   
89.
Auroras are caused by accelerated charged particles precipitating along magnetic field lines into a planetary atmosphere, the auroral brightness being roughly proportional to the precipitating particle energy flux. The Analyzer of Space Plasma and Energetic Atoms experiment on the Mars Express spacecraft has made a detailed study of acceleration processes on the nightside of Mars. We observed accelerated electrons and ions in the deep nightside high-altitude region of Mars that map geographically to interface/cleft regions associated with martian crustal magnetization regions. By integrating electron and ion acceleration energy down to the upper atmosphere, we saw energy fluxes in the range of 1 to 50 milliwatts per square meter per second. These conditions are similar to those producing bright discrete auroras above Earth. Discrete auroras at Mars are therefore expected to be associated with plasma acceleration in diverging magnetic flux tubes above crustal magnetization regions, the auroras being distributed geographically in a complex pattern by the many multipole magnetic field lines extending into space.  相似文献   
90.
Methylation of tRNAAsp by the DNA methyltransferase homolog Dnmt2   总被引:1,自引:0,他引:1  
The sequence and the structure of DNA methyltransferase-2 (Dnmt2) bear close affinities to authentic DNA cytosine methyltransferases. A combined genetic and biochemical approach revealed that human DNMT2 did not methylate DNA but instead methylated a small RNA; mass spectrometry showed that this RNA is aspartic acid transfer RNA (tRNA(Asp)) and that DNMT2 specifically methylated cytosine 38 in the anticodon loop. The function of DNMT2 is highly conserved, and human DNMT2 protein restored methylation in vitro to tRNA(Asp) from Dnmt2-deficient strains of mouse, Arabidopsis thaliana, and Drosophila melanogaster in a manner that was dependent on preexisting patterns of modified nucleosides. Indirect sequence recognition is also a feature of eukaryotic DNA methyltransferases, which may have arisen from a Dnmt2-like RNA methyltransferase.  相似文献   
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