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231.
Tsutomu OHGI Shunichi KAMIMURA Yasuhiro MINEZAKI Masanobu TAKAHASHI 《Animal Science Journal》2005,76(6):549-557
In the present study, 42 multiparous Holstein cows were used to investigate the relationship between fat accumulation in the liver and dry matter intake, milk yield and blood metabolites. Based on the percentage of fat in the liver cell at 2 weeks post‐parturition, the cows were classified into three groups. These groups were: (i) less than 10% of fat (normal group, n = 29); (ii) 10–20% of fat (mild group, n = 6); and (iii) more than 20% of fat (moderate group, n = 7). The bodyweight of the moderate group was high (771 kg) before calving. The sufficiency rates of total digestible nutrients (TDN) were remarkably decreased (approximately 65%) in early lactation. The milk fat yield and milk fat composition of the moderate group were higher (P < 0.05) than the other groups at 1 and 2 weeks post‐parturition. It was suggested that non‐esterified fatty acids (NEFA) mobilized from adipose tissues was directly used by the mammary gland for synthesis of milk fat. The percentage of bromsulfalein (BSP) retention of the moderate group was high (21.1%) at 30 min, and it showed that the BSP clearance function was significantly decreased. The concentrations of NEFA, β‐hydroxybutyric acid and glucose were appropriate indicators of energy status; however, aspartate aminotransferase, γ‐glutamyl transpeptidase and total bilirubin were not sensitive indicators of a moderate fatty liver. Thus, high‐yielding cows that calve in an overweight condition are more likely to develop excessive fat accumulation in the liver because of great mobilization from adipose tissues post‐parturition. In cows with a moderately fatty liver, a decrease in TDN sufficiency rates, an increase of milk fat yield and a reduction of liver function were observed in early lactation. The increase of serum NEFA and milk fat composition resulting from mobilization of adipose tissues helped to diagnose moderate fatty liver. 相似文献
232.
The aim of the present study was to clarify the effect of photoperiod on nighttime secretion of growth hormone (GH) in goats. Adult female goats were kept at 20°C with an 8 h or 16 h dark photoperiod, and secretory patterns of GH for 8 h in the dark period were examined with the profile of prolactin (PRL) secretion. GH was secreted in a pulsatile manner in the dark period. There were no significant differences in pulse frequency between the 8‐ and 16‐h dark photoperiods; however, pulse amplitude tended to be greater in the group with the 16‐h dark photoperiod (P = 0.1), and mean GH concentrations were significantly greater in the same photoperiod (P < 0.05). PRL secretion increased quickly after lights off under both photoperiods. The PRL‐releasing responses were weaker in the 8‐h than 16‐h dark photoperiod. The secretory response to photoperiod was more obvious for PRL than GH. The present results show that a long dark photoperiod enhances the nighttime secretion of GH in female goats, although the response is not as obvious as that for PRL. 相似文献
233.
Hiromitsu Furuya Keisuke Tubaki Tsutomu Matsumoto Shin-ichi Fuji Hideki Naito 《Journal of General Plant Pathology》2007,73(1):8-14
Roots of rice plants grown in paddy fields in a transplant culture system were collected seven times between 8 and 22 weeks
after transplanting, for two crop seasons. Rice seedlings grown in a potting medium amended with the collected roots were
significantly shorter than those grown in the same medium either without the addition of the roots or amended with pasteurized,
collected roots indicating that seedlings were inhibited by heat-labile microorganisms on the collected rice roots. Ninety-five
and 172 pure cultures of Pythium spp. and fungi, respectively, were isolated from the rice roots collected 5 or 7.5 weeks after transplanting in the fields.
Among these microorganisms, Pythium aristosporum inhibited seedling growth in greenhouse experiments, and Acremonium sp., Alternaria sp., Epicoccum nigrum, Fusarium sp., Massarina sp., Penicillium spp., Rhinocladiella sp., Stemphylium sp., Trichocladium sp., and several unidentified fungi inhibited seminal root growth in in vitro experiments. These microorganisms might be
involved in the inhibition of seedling growth in soils amended with the rice roots collected from the paddy field. Thus, roots
of rice plants at the middle stage of growth transplanted into paddy fields can harbor pathogenic or deleterious fungi or
Pythium sp(p). The effects of these microorganisms on rice growth in paddy fields are discussed. 相似文献
234.
Konosuke OTOMARU Yuki NAOI Kei HAGA Tsutomu OMATSU Takehiko UTO Motoya KOIZUMI Tsuneyuki MASUDA Hiroshi YAMASATO Hikaru TAKAI Hiroshi AOKI Shinobu TSUCHIAKA Kaori SANO Sachiko OKAZAKI Yukie KATAYAMA Mami OBA Tetsuya FURUYA Junsuke SHIRAI Kazuhiko KATAYAMA Tetsuya MIZUTANI Makoto NAGAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):321-324
During surveillance for bovine diarrhea of unknown causes in Japanese black cattle in Kagoshima Prefecture,
Japan, we found two types of novel kobu-like viruses in fecal samples of calves. Sequence analyses revealed
that they had L protein and 2A protein with H-box/NC sequence motif, which are present in kobuviruses.
Phylogenetic analysis revealed that they were related to kobuviruses; however, they clustered apart from other
kobuviruses. In the prevalence study of two types of novel kobu-like viruses, 16.9% and 10.4% prevalence of
these viruses were observed in the feces of diarrheal calves in this area. 相似文献
235.
236.
Antioxidant activity and constituents of propolis collected in various areas of Korea 总被引:10,自引:0,他引:10
Ahn MR Kumazawa S Hamasaka T Bang KS Nakayama T 《Journal of agricultural and food chemistry》2004,52(24):7286-7292
Propolis is a resinous substance collected by honeybees from various plant sources. The composition of propolis depends on time, vegetation, and the area of collection. This study examined the antioxidant activity of propolis from various areas of Korea: Chilgok, Cheongju, Geochang, Muju, Pocheon, and Sangju. Ethanol extracts of propolis (EEP) were prepared and evaluated for their antioxidant activity by beta-carotene bleaching, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization assays. Furthermore, the major constituents in EEP were identified by high-performance liquid chromatography analysis with a photodiode array and mass spectrometric detection, and each component was quantitatively analyzed. EEP from Cheongju and Muju had relatively strong antioxidant activity accompanied by high total polyphenol contents. Propolis from Cheongju contained large amounts of antioxidative compounds, such as caffeic acid, kaempferol, and phenethyl caffeate. On the other hand, propolis from Pocheon had compounds not seen in propolis from other areas. 相似文献
237.
Utiyama Masahiro Fukuyama Tsutomu Yamada Maruo Yasuko Ichino Toshihiro Izumi Katsuyuki Hara Hiroshi Takano Kenichi Suzuki Haruko Aoki Masatoshi 《Water, air, and soil pollution》2004,151(1-4):53-70
Concentrations of ozone and nitrogen oxides, together with air temperature and solar radiation intensity, were measured at several heights on a tower standing through the canopy of a red pine forest in summer and in autumn. In the summer observation, the diurnal variation patterns of ozone concentration both above and below the canopy were all similar and parallel to the solar radiation intensity. Using the data collected immediately above the canopy, deviation from the Leighton relationship and variations of concentration sums [O3] + [NO] and [NO2] + [NO] were examined, and as a result, it was supposedthat ozone was photochemically formed there in the daytime, probably because hydrocarbons emitted from pine trees broke the photostationary state among ozone and nitrogen oxides. The vertical temperature profile exhibited an inversion at the leaf-layer, which must have hindered vertical mixing of the air and made the trunk space more or less isolated from the upper atmosphere. These observations led to an idea that the similarity of the ozone variation pattern at every height was caused by the photochemical formation that proceeded simultaneously above and below the canopy rather than by vertical transport. Such situations of ozone formation were supported by observation of two maximums in the ozone vertical profile, one immediately above the canopy and another in the trunk space. Another feature of the ozone profile was a deep minimum in the leaf layer, which indicated ozone deposition onto leaf surfaces. This study thus revealed concurrence of ozone formation and deposition, and left two potentially important implications worthy of further investigation: (1) a forest is not always a sink but can be a source of ozone in sunlit conditions, and (2) deposition of ozone to trees can take place not only from outside but also from inside of a forest. In the autumn observation, however, the ozone formation was barely recognizable above the canopy and no longer found in the trunk space; in addition, the ozone concentration minimum in the leaf layer disappeared, suggesting that the deposition or removal was dependent on temperature. 相似文献
238.
The absence of Rhodococcus equi in Mongolian horses 总被引:1,自引:0,他引:1
Takai S Sengee S Madarame H Hatori F Yasuoka K Ochirel E Sasaki Y Kakuda T Tsubaki S Bandi N Sodnomdarjaa R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(6):611-613
In native Mongolian horses, the incidence and distribution of Rhodococcus equi are poorly understood. One hundred and fourteen equine fecal samples and 71 soil samples were collected from the camp sites of 26 nomadic families located in three areas less than 100 km from Ulaanbaatar, Mongolia. Five fecal samples were also collected from foals of Przewalski's Horses introduced into the Hustai National Park, Mongolia. No R. equi was isolated from the Mongolian horses or the soil samples. However, three colonies of R. equi were isolated from two fecal samples collected from foals of Przewalski's Horses. These isolates were avirulent, with neither 15- to 17-kDa antigens (VapA) nor a 20-kDa antigen (VapB) genes being detected. We concluded that native Mongolian horses and their environment appear free from contamination with R. equi. 相似文献
239.
Decomposition patterns of leaf litter of seven common canopy species in a subtropical forest: dynamics of mineral nutrients 总被引:2,自引:0,他引:2
XU Xiao-niu Hideaki SHIBATA Tsutomu ENOKI 《林业研究》2006,17(1):1-6
Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The species studied are representative for the vegetation in the study area and differed significantly in chemical qualities of their litter. No significant relationships were found between decomposition rate (percentage dry mass remaining and decomposition constant k) and initial element cuncentrations.However, there were significant correlations betweeu the percentage of dry mass remaining and the mineral element concentrations in the remaining litter for most cases. The rank of the element mobility in decomposition process was as follows: Na = K 〉 Mg ≥ Ca 〉 N ≥ Mn ≥ Zn ≥ P 〉 Cu 〉〉 Al 〉〉 Fe. Concentrations of K and Na decreased in all species as decomposition proceeded. Calcium and Mg also decreased in concentrntion but with a temporal increase in the initial phase of decomposition, while the concentrations of other elements (Zn, Cu, AL and Fei increased for all species with exception of Mn which revealed a different pattern in different species. In most species, microelements (Cu, Al, and Fe) significantly increased in absolute amounts at the end of the litterbag incubation, which could be ascribed to a lange extent to the mechanism of abiotic fixation to humic substances rather than biological immobilization. 相似文献
240.
Tsutomu Enoki Takafumi Inoue Naoaki Tashiro Hiroaki Ishii 《Journal of Forest Research》2011,16(4):268-274
We measured the aboveground biomass, biomass increment and litterfall production of a 140-year-old, abandoned Cryptomeria japonica plantation in order to infer the effects of topography on biomass production. The plantation was unsuccessful and the naturally
regenerated broad-leaved trees contributed 93.4% (374.2 Mg ha−1) of the total aboveground biomass (400.2 Mg ha−1). Comparing between different slope positions, aboveground biomass decreased downslope corresponding to the decrease in broad-leaved
tree biomass. The biomass of C. japonica did not vary with slope position. Biomass increment and litterfall production of the broad-leaved trees also decreased downslope.
However, litterfall production per unit biomass and aboveground net primary production per unit biomass increased downslope.
Results of a path analysis showed that biomass increment of C. japonica decreased with increasing topographical convexity, whereas biomass and litterfall production of broad-leaved tree increased.
Litterfall production of broad-leaved tree decreased with increasing biomass of C. japonica, suggesting that, despite their small biomass, the presence of residual C. japonica may have negative effects on the distribution and productivity of the broad-leaved trees. Our results indicated that total
aboveground biomass of the study site was comparable to that of old-growth C. japonica plantations. We inferred that the variation in aboveground biomass of the broad-leaved trees was largely determined by the
topography, while their productivity was affected by interactions with planted C. japonica. 相似文献