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231.
This study evaluated the protective effects of purple rice ( Oryza sativa L.) bran extract (PRE) and its major anthocyanidins (cyanidin and peonidin) against light-induced retinal damage. In an in vitro experiment, cultured murine photoreceptor cells (661W) were damaged by a 24 h exposure to light. Viability of 661W after light treatment, assessed by the tetrazolium salt (WST-8) assay and Hoechst 33342 nuclear staining, was improved by the addition of PRE, cyanidin, and peonidin. Intracellular radical activation in 661W, evaluated using the reactive oxygen species (ROS) sensitive probe 5-(and 6)-chloromethyl-2,7-dichlorodihydrofluorescein diacetate acetyl ester (CM-H(2)DCFDA), was reduced by PRE and its anthocyanidins. Electron spin resonance (ESR) measurements showed that PRE, peonidin, and cyanidin all exhibited radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical ((?)O(2)(-)), and hydroxyl radical ((?)OH). In an in vivo mouse experiment, intravitreous injection of PRE significantly suppressed photoreceptor degeneration induced by exposure to light as revealed by histological analysis using hematoxylin-eosin staining. These findings suggest that PRE and its anthocyanidins possess protective effects with antioxidation mechanism in both in vitro and in vivo models of retinal diseases.  相似文献   
232.
We carried out a genetic association study between five nucleotide polymorphisms (5′UTR microsatellite ((TG)n), nt‐7(C>A), L24V, DelR242 and Intron 1 microsatellite) of the GHSR1a gene and growth and carcass traits in 1285 steers sired by 117 Japanese Black bulls in a progeny testing program. We report herein, a significant association between the 5′UTR microsatellite and nt‐7(C>A) loci and growth and carcass traits. We also propose a translational hypothesis that the association is due to differences in the secondary structure of GHSR1b mRNA (the non‐spliced type with the 5′UTR microsatellite) among the GHSR1a gene haplotypes. Furthermore, we predicted the potential increase in profitability due to increased carcass weight in cow‐calf fattening enterprises through planned matings based on DNA testing of the 5′UTR microsatellite. Statistical analysis revealed that the 5′UTR microsatellite locus had a significant additive effect on carcass weight (CW) and average daily gain (ADG), but not on beef marbling score (BMS). One of the four major microsatellite alleles (19‐TG allele) with an allele frequency of 0.145, had a significantly (P < 0.0007) desirable effect on CW and ADG. We concluded that the 19‐TG allele could potentially be economically useful nucleotide markers for growth and carcass traits in Japanese Black cattle.  相似文献   
233.
234.
Recently, we reported a method for identifying the Nagoya, a Japanese chicken breed. Here we describe an improved method suitable for use in conventional laboratories. Five microsatellite markers fixed in the Nagoya breed were amplified by multiplex polymerase chain reaction (PCR). The PCR products were digested with CEL I nuclease and electrophoresed in a ready‐made gel. The fragment‐length polymorphisms of each marker were detected clearly in the gel, and the resultant exclusion probabilities were almost equal to that in our previous data. This method can be used in laboratories without a DNA sequencer for routinely discriminating between the Nagoya breed and other chickens.  相似文献   
235.
Various types of wood-based boards were analyzed for deterioration after being exposed to an outdoor environment for 5 years in Tsukuba, Japan. In phenol–formaldehyde resin bonded particleboard (PB(PF)) and aspen oriented strand board (OSB(aspen)), longer exposure caused a greater reduction in the modulus of rupture and internal bond strength, an increase in the coefficients of variation, and a decrease in 95 % lower tolerance limit at the 75 % confidence level (95TL). Nail-head pull-through and lateral nail resistance were also reduced by outdoor exposure, but their coefficients of variation and 95TL were not significantly affected. In contrast, methylene diphenyl diisocyanate bonded medium density fiberboard (MDF(MDI)) only showed a slight deterioration of these properties even after 5-year exposure, and the coefficients of variation and 95TL hardly changed. After 5-year exposure, the retention of shear load in one-plane at relative displacement of 1.0 mm was high in MDF(MDI) and OSB(aspen) at 93.5 and 78.5 %, respectively, but low in PB(PF) at 41.1 %. As with PB(PF), OSB(aspen) also showed a sharp decrease in the modulus of rupture and internal bond strength, but only slightly reduced shear load in one-plane.  相似文献   
236.
The purpose of this study was to investigate the effects of semen collection into tubes containing extender supplemented with BSA on the cryosurvival of goat spermatozoa. Semen was collected from two goats into empty tubes or tubes containing 10 ml extender supplemented with 0, 0.1, 1, or 5% BSA, and the washed spermatozoa were frozen as pellets in egg yolk-trehalose extender with the addition of 0.04% SDS and 4% glycerol. Sperm motion parameters were evaluated after post-thawing and during a thermal resistance test. The acrosome status of frozen-thawed spermatozoa was also observed using FITC-PNA staining. In frozen semen that was collected into tubes containing extender supplemented with 5% BSA, the post-thawed spermatozoa exhibited a significant improvement in motion parameters and maintained high motility throughout incubation and acrosome integrity, as compared with semen collected into tubes containing extender supplemented with lower concentrations of BSA. In conclusion, semen collection into tubes with a large volume of extender containing high concentrations of BSA dramatically improves the motility and acrosome integrity of frozen-thawed spermatozoa. This suggests that the in vitro functional freezability of spermatozoa is abruptly modified by reducing contact with seminal plasma and by flash contact with BSA at ejaculation.  相似文献   
237.
To evaluate the practical application of an indoor seed orchard, we compared the seed production, final germination rates and mating patterns of potted Cryptomeria japonica D. Don clones in two miniature seed orchards: one in a glasshouse and the other outdoors. There was no statistically significant difference in total seed production between the orchards (P = 0.275, ANOVA). However, the final germination rate of seeds produced in the indoor orchard was significantly lower than that of seeds produced in the outdoor orchard (P < 0.01, Wilcoxon test). The average self-fertilization rate was higher in the indoor orchard (27.2%) than in the outdoor orchard (5.6%), and this parameter was strongly associated with the reduced final germination rates of the seeds harvested in the glasshouse. Pollen contamination was considerably lower in the indoor seed orchard (48.9% in the outdoor seed orchard and 4.4% in the indoor seed orchard). χ2 tests indicated that the paternal contributions of each constituent clone differed significantly in both orchards (P < 0.001 in both cases). The strong variations in paternal contributions among indoor orchard clones was significantly correlated with their respective pollen production capacities (Spearman ρ = 0.693, P < 0.001). To reduce the high self-fertilization rates, we recommend the use of orchard clones with similar pollen production capacity in indoor seed orchards.  相似文献   
238.
Sensitivity of Fusarium moniliforme Isolates to Ipconazole   总被引:1,自引:0,他引:1  
To estimate the sensitivity of Fusarium moniliforme to ipconazole, a sterol biosynthesis inhibitor (SBI), minimum inhibitory concentrations (MIC) were determined for isolates which were collected before the launch of ipconazole as a rice seed disinfectant. Research institutes from various prefectures in Japan supplied 211 isolates (group I) from their collections, and 84 isolates (group II) were isolated from rice paddy fields in Iwaki, Fukushima Prefecture. In group I, the MIC ranged from 0.10 to 6.25 μg/ml with a peak at 0.39 μg/ml. In group II, MIC values had the same range as group I, but the main peak was at 0.20 μg/ml. Ipconazole sensitivity did not differ significantly among groups I and II. Though the ranges of MIC values for ipconazole, pefurazoate and triflumizole were different in 60 isolates randomly chosen from group I, positive correlations were observed in their sensitivities to SBIs, suggesting a common mechanism in F. moniliforme for lowering sensitivities to SBIs. Among the 14 isolates tested, isolates with MIC values lower than 0.78 μg/ml for ipconazole were pathogenic to rice seedlings, and all the isolates with MIC values higher than or equal to 1.56 μg/ml were not pathogenic in the nursery test. Good protection against isolates causing “Bakanae” disease was obtained by dipping seeds for 24 hr in ipconazole. The pathogenic isolates can be controlled by the seed treatment with the practical dosage of ipconazole because of the adequate margin between the highest MIC value for the pathogenic isolates and the treatment concentration. In addition, the low or lack of pathogenicity of the isolates less sensitive to ipconazole may also contribute to the stable efficacy of ipconazole. Received 8 November 1999/ Accepted in revised form 18 April 2000  相似文献   
239.
The density of Myrothecium roridum increased in field soil from June to October and decreased from February to April in 1996–1998. The fluctuation in density of M. roridum in the surface soil was affected by the average temperature. In the greenhouse, mulberry leaves were infected by conidia that splashed from soil artificially infested with conidia of M. roridum at 103 or more conidia/g soil. Disease incidence on mulberry increased when soil was amended with the fallen leaves and when mulberries were planted densely in soil artificially infested with a high conidial density of M. roridum. Received 9 December 1999/ Accepted in revised form 21 July 2000  相似文献   
240.
Recent studies have indicated that the phytohormone abscisic acid (ABA), induced in response to a variety of environmental stresses, plays an important role in modulating diverse plant–pathogen interactions. In Arabidopsis thaliana, we previously clarified that ABA suppressed the induction of systemic acquired resistance (SAR), a plant defense system induced by pathogen infection through salicylic acid (SA) accumulation. We investigated the generality of this suppressive effect by ABA on SAR using tobacco plants. For SAR induction, we used 1,2-benzisothiazole-3(2H)-one 1,1-dioxide (BIT) and benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) that activate upstream and downstream of SA in the SAR signaling pathway, respectively. Wild-type tobacco plants treated with BIT or BTH exhibited enhanced disease resistance against Tobacco mosaic virus (TMV) and tobacco wildfire bacterium, Pseudomonas syringae pv. tabaci (Pst), however, which was suppressed by pretreatment of plants with ABA. Pretreatment with ABA also suppressed the expression of SAR-marker genes by BIT and BTH, indicating that ABA suppressed the induction of SAR. ABA suppressed BTH-induced disease resistance and pathogenesis-related (PR) gene expression in NahG-transgenic plants that are unable to accumulate SA. The accumulation of SA in wild-type plants after BIT treatment was also suppressed by pretreatment with ABA. These data suggest that ABA suppresses both upstream and downstream of SA in the SAR signaling pathway in tobacco.  相似文献   
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