全文获取类型
收费全文 | 146篇 |
免费 | 3篇 |
专业分类
林业 | 44篇 |
农学 | 9篇 |
21篇 | |
综合类 | 4篇 |
农作物 | 4篇 |
水产渔业 | 6篇 |
畜牧兽医 | 51篇 |
园艺 | 2篇 |
植物保护 | 8篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 6篇 |
2012年 | 10篇 |
2011年 | 9篇 |
2010年 | 6篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 7篇 |
2006年 | 12篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 9篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
排序方式: 共有149条查询结果,搜索用时 296 毫秒
81.
Satoshi Yamaguchi Yutaka Masuda Satoshi Nakagawa Hayato Abe Yusaku Gotoh Toshimi Baba Takayoshi Kawahara 《Animal Science Journal》2019,90(8):915-923
The objectives of this study were to estimate the heritability of mastitis incidence and genetic correlations between the mastitis and the somatic cell score (SCS) statistics, and to compare the practicability between different models. We used test‐day records with the mastitis incidence and SCS collected from Holstein cows calving from 1988 to 2015 in Hokkaido, Japan. As indicators of mastitis, the average SCS (avSCS), the standard deviation of SCS (sdSCS), and the maximum SCS (maxSCS) were calculated using test‐day records up to the first 305 days in milk within a lactation. We compared a four‐trait repeatability animal model (MTRP) with a four‐trait multiple‐lactation animal model (MTML). The heritability for mastitis was equal to or lower than 0.05 in all the models. Genetic correlations between lactations with MTML within the same trait were positive and close to 1. With MTRP, the estimated genetic correlations of the mastitis incidence with avSCS, sdSCS, and maxSCS were 0.66, 0.79, and 0.82, respectively. A joint evaluation with SCS statistics is expected to give an extra reliability for mastitis because of high and positive genetic correlations among the traits. 相似文献
82.
The effect of inoculation with Frankia, a N-fixing actinomycete, on the growth of Alnus sieboldiana seedlings was studied on unsterilized soil from a nursery and an alder stand (forest of Alnus firma). The seedlings of A. sieboldiana were inoculated with Frankia before or after a 2-month culture on sterilized vermiculite, during which they nodulated, and transplanted to unsterilized
soil from the nursery and the alder stand. The control seedlings were also cultured on sterilized vermiculite for about 2 months
and transplanted to unsterilized soil without Frankia inoculation. The seedling growth, nodulation and N-fixing activity were measured 3, 10 and 16 weeks after the transplantation.
Growth and nodule biomass of the seedlings inoculated with Frankia and those grown on the alder soil were better than those without inoculation with Frankia and grown on the nursery soil, respectively. The seedlings inoculated before spontaneous nodulation grew better than those
inoculated at the transplantation. Nitrogen-fixing activity measured by acetylene reduction assay at 16 weeks after the transplantation
was higher in the seedlings grown on the soil from the nursery than on the soil from the alder stand. 相似文献
83.
We evaluated the response of Japanese larch (Larix kaempferi Sieb. & Zucc.) to elevated atmospheric CO(2) concentration ([CO(2)]) (689 +/- 75 ppm in 2002 and 697 +/- 90 ppm in 2003) over 2 years in a field experiment with open-top chambers. Root activity was assessed as nitrogen, phosphorus and potassium uptake rates estimated from successive measurements of absorbed amounts. Dry matter production of whole plants was unaffected by elevated [CO(2)] in the first year of treatment, but increased significantly in response to elevated [CO(2)] in the second year. In contrast, elevated [CO(2)] increased the root to shoot ratio and fine root dry mass in the first year, but not in the second year. Elevated [CO(2)] had no effect on tissue N, P and K concentrations. Uptake rates of N, P and K correlated with whole-plant relative growth rates, but were unaffected by growth [CO(2)], as was ectomycorrhizal colonization, a factor assumed to be important for nutrient uptake in trees. We conclude that improved growth of Larix kaempferi in response to elevated [CO(2)] is accompanied by increased root biomass, but not by increased root activity. 相似文献
84.
Daisuke Tatsumi Takashi Higashihara Shin'ya Kawamura Takayoshi Matsumoto 《Journal of Wood Science》2000,46(5):405-409
The effect of ultrasound on the quality of recycled fibers was investigated. Ultrasound was applied to recycled pulp fiber suspension before ink removal by conventional flotation. The ultrasonic treatment induced an increase in the sedimentation volume of the fiber, which implies that the flexibility and bulkiness of the fiber increase. The water retention value of the ultrasonically treated fiber recovered from the loss caused by the recycling. These facts are due to a beating effect of the treatment. The paper sheets prepared from the ultrasonically treated fiber suspension showed higher sheet density, tensile strength, and brightness than that from an untreated fiber suspension. The process, which consists of ultrasonic treatment for 1 min following flotation deinking, requires about 1.4 times as much energy as the conventional flotation deinking process, but it induced 20% improvement in brightness. The results indicate that the ultrasonic treatment is effective in improving recycled fiber quality.This report was presented in part at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998; and at the 5th Annual Meeting of the Japan Cellulose Society, Kyoto, July 1998 相似文献
85.
Yasuo Nakamura Tadashi Nakano Tatsuya Yurimoto Yukio Maeno Takayoshi Koizumi Akio Tamaki 《Fisheries Science》2010,76(6):931-941
We assessed the reproductive cycle of the venerid clam Meretrix lusoria by histological analysis of the gonads. Individuals for study were collected from natural populations on the Shirakawa tidal
flat, Ariake Sound, and from populations that had been transplanted from the Shirakawa flat to the Oi flat in Tokyo Bay. In
both study areas, the reproductive cycle was synchronized between sexes. Gonads of the clam started to develop in early spring
and matured during the summer. Mass spawning occurred in the late summer/early fall. The clam matured at a shell length of
17–20 mm, which is much smaller than previously considered. While trophic conditions and salinity differed considerably in
the two study areas, water temperatures showed similar seasonal changes (12°C during the winter and around 30°C during the
summer). Thus, temperature probably controlled gonadal development. The coincidence of the period of spawning with the period
of frequent intrusion of hypoxic waters into the tidal flats in Tokyo Bay suggests that such hypoxic events interfere with
clam recruitment and are at least partly responsible for the disappearance of the natural population at this location. 相似文献
86.
Takeo Sakaigaichi Yoshifumi Terajima Takayoshi Terauchi 《Plant Production Science》2017,20(2):157-161
High-level cutting without stubble shaving has been recommended in the cultivation of forage sugarcane, KRFo93-1. However, it is unclear whether this management practice is appropriate for the more recently developed variety Shimanoushie. Therefore, the aim of this study was to compare the dry matter yield of both varieties to high-level cutting. The study included five ratoon crops (RC1–RC5). In KRFo93-1, dry matter yield was higher in HC plots (high-level cutting without stubble shaving plots) than in Control plots (stubble shaving after high-level cutting plots), and the differences were significant for the first three ratoon crops. A similar trend was observed in Shimanoushie; however, the dry matter yield of HC plots was slightly lower than Control plots in RC4 and RC5 owing to a lower stem number. Although the sum of dry matter yield of five ratoon crops was significantly higher in HC plots of both varieties, the influence of high-level cutting was more effective in KRFo93-1 than in Shimanoushie. 相似文献
87.
Morimoto M Tanimoto K Nakano S Ozaki T Nakano A Komai K 《Journal of agricultural and food chemistry》2003,51(2):389-393
The antifeedant polymethylated flavones 5-hydroxy-3,6,7,8,4'-heptamethoxyflavone, 5-hydroxy-3,6,7,8-tetramethoxyflavone, and 5,6-dihydroxy-3,7-dimethoxyflavone have been isolated from the cudweed, Gnaphalium affine D. Don (Compositae). These flavonoids and authentic analogues showed insect antifeedant activity against the common cutworm (Spodoptera litura F.). In a previous paper, it was suggested that there was no substituent on the B-ring of the flavonoid for the beneficial antifeedant activity against the common cutworm. These flavonoids having a phenyl group as the B-ring and the chromone as elimination of the B-ring from the flavonoids were used to test the hypothesis of the previously described B-ring effect. The known fact is that Sculletaria baicarensis (Rutaceae) produced the 2-phenyl flavone. Test compounds and their methylated derivatives were prepared from this material for the structure-activity relationship (SAR) study of insect antifeedant activity. In spite of the 2-phenyl flavonoids, some tested compounds did not show any insect antifeedant activity against the common cutworm, although these inactive flavonoids were deficient in the 6-substituent group on the A-ring of the flavonoid. This 6-position-substituted derivative almost showed strong insect antifeedant activity against common cutworm. Moreover, the tested flavonoids having a hydroxyl group as a substituent on any of the positions tended to increase the activity. These results suggested the importance of the 6-position substitution on the flavonoid; however, hydrophilic substituents decreased the activity. Baicalein (5,6,7-trihydroxyflavone) derivatives did not show any activity despite having the 6-substituent derivative. Although the activity of some chromones increased the activity of the flavone, the bulky B-ring was a disadvantage for the antifeedant activity. It was suggested that the charge on C(3) and C(5) of the flavonoid was important for the biological activity. Additionally, an adequate hydrogen bonding property, which is different from lipophilicity, was an advantage for the activity on the basis of a QSAR analysis. 相似文献
88.
Joni Kujansuu Koh Yasue Takayoshi Koike Anatoly P. Abaimov Takuya Kajimoto Takashi Takeda Morihiko Tokumoto Yojiro Matsuura 《Journal of Wood Science》2007,53(2):87-93
An analysis was performed on the climatic responses of the radial growth of Larix gmelinii (Rupr.) Rupr. on contrasting north-facing and south-facing slopes in Tura, central Siberia. We developed chronologies of
tree-ring width for four plots, designated as north-upper, northlower, south-upper, and south-lower. Both residual and standard
chronologies of tree-ring widths exhibited a significant positive correlation with temperature from the end of May until early
June in all four plots. The chronologies of ring width did not reveal any major difference in the response to temperature
among the four plots. The standard chronologies of ring widths on the north-facing slope were negatively correlated with precipitation
during the winter (October–April) and in early and mid-May, whereas the residual chronologies did not reveal clear relationships
with precipitation during the winter and May. The significant correlation between ring width and temperature from the end
of May until early June indicates that temperatures in springtime play a significant role in the radial growth of L. gmelinii. The negative correlations between standard chronologies of tree-ring width and precipitation in the winter and in May on
the north-facing slope indicate that lowfrequency fluctuations in snowfall have negative effects on the radial growth. However,
these effects vary and depend on the microscale topography.
Part of this report was presented at the 55th Annual Meeting of the Japan Wood Society, March 2005, Kyoto 相似文献
89.
To elucidate the chemical structure ofp-hydroxycinnamyl aldehyde moieties of abnormal angiosperm lignins of cinnamyl alcohol dehydrogenase down-regulated plants, sinapyl and coniferyl aldehydes were subjected to thioacidolysis. and the products were analyzed by gas chromatograph-mass spectrometer (GC-MS). The chromatograms indicated that two pairs of new isomeric compounds were released during thioacidolysis of sinapyl and coniferyl aldehydes, respectively, together with the previously found products. These products were also found in the thioacidolysis products of dehydrogenation polymer incorporatingp-hydroxycinnamyl aldehydes. The new compounds had the novel indane structure in that they position of the side chain was linked to an aromatic ring. In the case of sinapyl aldehyde, these isomer compounds were the main products, which indicated different reactivities of sinapyl and coniferyl aldehydes during thioacidolysis.Part of this paper was presented at the TAPPI Pulping Conference. Nashville, October 1996; and the 41st Lignin Symposium, Nagoya. October 1996 相似文献
90.
The role of the cinnamate pathway in monolignol biosynthesis based on feeding experiments with lignifying plant stems and
characterization of the enzymes in the pathway, O-methyltransferase (OMT), cinnamyl alcohol dehydrogenase (CAD), etc. is discussed. Monolignol biosynthesis via metabolic grids
according to newly characterized enzymes in the pathway is also reviewed and discussed. The cleavage mechanisms of side chains
and aromatic rings by lignin peroxidase and laccase elucidated by using 18O, 2H, and 13C labeled lignin substructure dimers and DHP with 18O2 and H2
18O are reviewed. Finally, the prospects of lignin biochemistry in the wood and paper industries are discussed according to
the recent progress on gene technology on wood formation and microbial degradation of lignin. 相似文献