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71.
Toshihiro Okamura Kazuo Ishii Motohide Nishio Guilherme J. M. Rosa Masahiro Satoh Osamu Sasaki 《Animal Science Journal》2020,91(1)
Direct selection for litter size or weight at weaning in pigs is often hindered by external interventions such as cross‐fostering. The objective of this study was to infer the causal structure among phenotypes of reproductive traits in pigs to enable subsequent direct selection for these traits. Examined traits included: number born alive (NBA), litter size on day 21 (LS21), and litter weight on day 21 (LW21). The study included 6,240 litters from 1,673 Landrace dams and 5,393 litters from 1,484 Large White dams. The inductive causation (IC) algorithm was used to infer the causal structure, which was then fitted to a structural equation model (SEM) to estimate causal coefficients and genetic parameters. Based on the IC algorithm and temporal and biological information, the causal structure among traits was identified as: NBA → LS21 → LW21 and NBA → LW21. Owing to the causal effect of NBA on LS21 and LW21, the genetic, permanent environmental, and residual variances of LS21 and LW21were much lower in the SEM than in the multiple‐trait model for both breeds. Given the strong effect of NBA on LS21 and LW21, the SEM and causal information might assist with selective breeding for LS21 and LW21 when cross‐fostering occurs. 相似文献
72.
The amount of K and Na in HCI-extract of soils has been determined by various methods, using the flame photometer, and specific reagents, but none of these methods are fully satisfactory from a view point of cost or accuracy; Poul Porter et al.1) have pointed out the large errors that have frequently occured in tlamephotometry. 相似文献
73.
Investigations on the extraction and determination of organic acids in flooded soil have been reported by TAKAI (1) and TAKIJIMA (2). TAKAI applied water to extract acids from soil and determined them by BULLEN's method (3). However, TAKIJIMA reported that organic acid could not be completely extracted by TAKAI's procedure, especially in soil with a high organic matter content such as muck and peaty soils, and proposed an extraction procedure with 0.5 N sulfuric acid. He also discussed the absorption of acids by soil. 相似文献
74.
Color change of city refuse during composting process was investigated according to the methods of measurement for color of materials based on the CIE 1931 Standard Colorimetric System. Stimulus value Y (the degree of lightness) and chromaticity coordinates (x, y) were determined with Color Analyzer by measuring relative spectral reflectance. Stimulus value Y of city refuse decreased during composting process, but chromaticity coordinates (x, y) scarcely changed. Color of various composts, which were produced from city refuse, straw, hog fecal wastes, tree bark, and tree bark mixed with activated sludge, were also investigated by measuring relative spectral reflectance. The shapes of the reflection spectra of city refuse were different from those of the other composts. Colors of the various composts were similar to each other when specified according to their three attributes: value, hue, and chroma (Munsell renotation). While city refuse was rotting and maturing, stimulus value Yand C/N ratio equally decreased. A positive correlation was found between stimulus value Y and C/N ratio. It was concluded that stimulus value Y can be used as a criterion for determining the degree of maturity of city refuse compost. The correlation between stimulus value Y and C/N ratio of various composts was also investigated. According to the position on the two coordinates having stimulus value Y and C/N ratio as axe s, various composts were classified into three groups: (i) city refuse compost group, (ii) straw compost group, and (iii) tree bark compost group. 相似文献
75.
Toshisuke Maruyama Iwao Hashimoto Kazuo Murashima Hiroshi Takimoto 《Paddy and Water Environment》2008,6(4):355-362
Kahokugata Lake, a closed lake, has been subject to eutrophication. This research was conducted to clarify the actual phenomena
and evaluation of the discharges of N and P from paddy test fields in the lowlands into Kahokugata Lake. A comprehensive mass
balance of N and P was obtained from 4 years of study. About N, the mean value of harvested unhulled rice (79.9 kg/ha) was
greater than mean controlled release fertilizer inputs (56.7 kg/ha). Other inputs and outputs include N in atmospheric acid
deposition (21.4 kg/ha) and N fixation–denitrification (9.2 kg/ha). The rice straw recycled after harvest was balanced by
straw produced in the succeeding year. The runoff and percolation losses discharged into the lake was 11.3 kg/ha, (8.6% of
total inputs). Since the rice harvested was consumed domestically, which taking out from the farmland and, therefore, nitrogen
pollutant into the lake was becoming small, paddy rice at this site is considered an “anti-polluting, purifying or cleansing”
crop. The P content in harvested rice (39.4 kg/ha) was balanced by fertilizer inputs (36.4 kg/ha). Previous studies examining
inflow–outflow relationships without considering a comprehensive mass balance may lead to erroneous conclusions. Our findings
indicate paddy rice in lowlands could be an environmentally friendly crop and can play an important role in reducing pollution
of lakes, and therefore should be considered in land use planning. 相似文献
76.
77.
Fumio NAMIKI Kanji SHIMIZU Kyoko SATOH Tetsuo HIRABAYASHI Kazufumi NISHI Tsuruo KAYAMURA Takashi TSUGE 《Journal of General Plant Pathology》2000,66(1):12-17
In 1994, Fusarium wilt of melon cultivars which are resistant to races 0 and 2 of Fusarium oxysporum f. sp. melonis was observed in southern area of the Lake Biwa region, Shiga prefecture. In commercial fields, mature plants of cv. Amus
which were grafted onto cv. Enken Daigi 2, and of cv. FR Amus showed yellowing, wilting and finally death before harvesting
of fruits. Diseased plants had vascular and root discolorations, and their stem sections yielded typical colonies of F. oxysporum. When the Shiga strains were tested for their pathogenicity to 12 species of cucurbits, they caused wilts only on melon.
Using race differential cultivars of melon, the Shiga strains were classified as race 1 of F. oxysporum f. sp. melonis, which has not been reported in Japan. To further characterize their pathogenicity, the strains were used to inoculate 46
additional cultivars of melon, oriental melon and oriental pickling melon. All the race 1 strains were pathogenic to the cultivars
tested, and their host range was apparently different from those of strains belonging to other races (races 0, 2 and 1,2y).
DNA fingerprinting with a repetitive DNA sequence, FOLR3, differentiated race 1 strains from strains of races 0 and 2, but
not from race 1,2y strains.
Received 2 July 1999/ Accepted in revised form 30 September 1999 相似文献
78.
79.
Effect of dietary fish meal levels on environmental phosphorus loading from carp culture 总被引:2,自引:0,他引:2
P ARVEEN JAHAN T AKESHI WATANABE S HUICHI SATOH V ISWANATH KIRON 《Fisheries Science》2000,66(2):204-210
80.
Milagros Virhuez MENDOZA Kenzo YONEMITSU Keita ISHIJIMA Yudai KURODA Kango TATEMOTO Yusuke INOUE Hiroshi SHIMODA Ryusei KUWATA Ai TAKANO Kazuo SUZUKI Ken MAEDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(7):992
In Japan, hepatitis E virus (HEV) causes hepatitis in humans through the consumption of raw or undercooked meat, including game meat. In the present study, nationwide surveillance of HEV infection among a total of 5,557 wild animals, including 15 species, was conducted in Japan. The prevalence of anti-HEV antibodies in wild boar was 12.4%, with higher positive rates in big boars (over 50 kg, 18.4%) than in small individuals (less than 30 kg, 5.3%). Furthermore, HEV RNA was more frequently detected in piglets than in older boars. Interestingly, the detection of HEV among wildlife by ELISA and RT-PCR suggested that HEV infection in Sika deer was a very rare event, and that there was no HEV infection among wild animals except for wild boar, Sika deer and Japanese monkeys. In conclusion, wild boar, especially piglets, are at high risk of HEV infection, while other wild animals showed less risk or no risk of HEV transmission. 相似文献