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191.
Takeshi Yamamoto Takao Shima Hirofumi Furuita Manabu Shiraishi F Javier Sánchez-Vázquez Mitsuo Tabata 《Fisheries Science》2001,67(3):420-429
SUMMARY: Macronutrient self-selection patterns in rainbow trout and common carp, which were maintained in groups, were examined when both water temperature and duration of light phase gradually decreased. Three semipurified macronutrient diets composed mainly of protein (casein and gelatin; crude protein (CP) = 65%), fat (pollock oil and soybean oil; crude fat (CF) = 38%), or digestible carbohydrate (dextrin and gelatinized starch; crude starch (CS) = 57%) were offered to five groups of trout (20 fish/group, 51 g/fish) and carp (15 fish/group, 36 g/fish) using three self-feeders. A standard diet (ST) containing the three macronutrients at an appropriate ratio (CP = 47%, CF = 14%, CS = 25%) was also offered to three groups each by a single self-feeder. After an initial 3 weeks of experiencing a long photoperiod (14 h light : 10 h dark cycle) and high water temperature (trout, 17°C; carp, 25°C), the light phase and temperature were gradually decreased in the following 3 weeks to 10 h light : 14 h dark, and 8°C for trout and 13°C for carp, and feeding was continued for a further 3 weeks under low temperature and short photoperiod conditions. Growth and protein utilization parameters between the ST diet self-fed groups and macronutrient diet self-selection groups were not different ( P > 0.05) for both trout and carp. Trout preferred the high-protein diet (HP) to the high-fat and the high-carbohydrate diets ( P < 0.05) regardless of the changes in water temperature and photoperiod. Carp also preferred the HP diet ( P < 0.01) under the high temperature and long photoperiod conditions; however, this preference gradually disappeared with lower temperatures and shorter photoperiods. These results suggest that the most appropriate macronutrient ratios in carp diets change with environmental conditions. 相似文献
192.
Takeo Yoshida Takao Masumoto Tomijiro Kubota Shuh Matsuda 《Paddy and Water Environment》2008,6(2):189-198
Agricultural water use on upland fields depends mainly on precipitation and irrigation by small wells in the Kashima plateau
basins. To establish a stable supply of water for irrigated upland fields, an evaluation of water-cycle mechanisms on an arable
plateau near plain lakes is important. Previous research suggests that groundwater catchments do not necessarily coincide
with the corresponding surface catchments in the plateau basins. However, a physical mechanism of groundwater movement has
not yet been clearly demonstrated. In this paper, therefore, we aimed to estimate the areas of groundwater catchments that
did not coincide with their corresponding surface catchments, by observing groundwater flow in boreholes and by evaluating
water balances of four small basins on the Kashima plateau. As a result, hydrological and groundwater observations in the
Kashima-Kohoku basin showed: (1) the groundwater catchment was larger than the surface catchment, as inferred from continuous
groundwater observations and the observed directions of groundwater flow, (2) groundwater potential may change after intensive
rains, especially after precipitation events of more than 50 mm, and (3) estimates of the long-term water balance confirmed
that groundwater flowed into the surface catchment from the outside. The area of the Kashima-Kohoku groundwater catchment
was 1.3–2.4 times the area of the surface catchment. Furthermore, the same result was obtained for two other basins. 相似文献
193.
Michiko Hayano Naoki Horikawa Tsuneo Kuwagata Jun Furuya Yasushi Ishigooka Toshihiro Hasegawa Tomoyuki Taniguchi Akira Shimizu Hitoshi Toritani Minoru Tada Takao Masumoto 《Paddy and Water Environment》2008,6(1):15-23
This paper introduces the Agriculture, Forestry and Fisheries Research Council of Japan (AFFRC) model, an integrated model
that predicts future rice production in the Mekong River basin by taking into account the effect of global warming on both
the water cycle and the rice economy. The model focuses especially on the water balance of paddy fields for different farmland
water use systems. We defined six categories of irrigated paddies and three categories of rain-fed paddies on the basis of
their systems of water usage. We included a process-based model to predict future rice production, accounting for daily changes
in available water resources such as precipitation. Many models of crop production treat rice in the same way as other crops;
the particular characteristics of rice farming are considered in more detail in our model. Our results show that it is possible
to estimate future rice production in the Mekong River basin by taking into account changes in available water, and to model
the resultant effects on the grain market. 相似文献
194.
Takeshi Yamamoto Koji Konishi Takao Shima Hirofumi Furuita Nobuhiro Suzuki Mitsuo Tabata 《Fisheries Science》2001,67(2):221-227
SUMMARY: An 8-week feeding experiment was conducted to examine the influence of fat and carbohydrate levels in a 40% protein level diet on growth and body composition of rainbow trout Oncorhynchus mykiss under self-feeding conditions. Five fish meal-based diets were prepared to include gelatinized potato starch at four levels (9, 18, 27, and 36%) and dextrin (34%). Dietary fat levels were isoenergetically reduced from 18 to 7% by the digestible carbohydrates. Each diet was fed to four replicate groups (28 g/fish, 20–23 fish/group) using self-feeders. Specific growth rate, percentage weight gain and percentage protein retention did not differ between the treatments. Feed efficiency and protein efficiency ratios were higher in the 18% starch (s18) and s27 diet groups, and decreased in higher fat or carbohydrate diet groups. Although gross energy intake (kJ/kg BW per day) decreased as the starch level increased, levels of digestible energy intake did not differ between the treatments. Fat levels in the carcass, viscera and liver decreased as dietary carbohydrate level increased. These results suggest that a 40% protein diet with either 15% fat and 18% starch or 11% fat and 27% starch is appropriate for juvenile rainbow trout under self-feeding conditions. 相似文献
195.
Liyan Wang Liming Bai Daisuke Tokunaga Yusuke Watanabe Toshiaki Hasegawa Jun-ichi Sakai Wanxia Tang Yuhua Bai Katsutoshi Hirose Takao Yamori Akihiro Tomida Takashi Tsuruo Masayoshi Ando 《Journal of Wood Science》2008,54(5):390-401
Twelve basic taxoids and 22 neutral taxoids were isolated from basic and polar neutral fractions of the extracts of needles
and twigs of Taxus cuspidata. Among them, taxine NA-13, 3,11-cyclotaxinine NN-1, taxinine NN-6, 11(15→1)abeo-taxinine NN-1, taxine NA-8, and taxine NA-4 were isolated first from natural sources by us. The cytotoxic activity of isolated
compounds was evaluated against three human cell lines: normal human fibroblast cells (WI-38), malignant tumor cells induced
from WI-38 (VA-13), and human liver tumor cells (HepG2). 7-Epitaxol, 7-epicephalomannine, taxinine NN-6, taxine NA-2, taxuspine
H, and taxagifine were active toward VA-13 cells and 7-epitaxol, 7-epicephalomannine, taxinine NN-1, 9,10-deacetyltaxinine,
and taxagifine were active toward HepG2 cells. The multidrug-resistant (MDR) cancer reversal activity of isolated compounds
was evaluated on the basis of the amount of vincristine (VCR) accumulated in MDR human ovarian cancer 2780 AD. Taxine NA-8,
taxine NA-2, 5-cinnamoyl-10-acetyltaxicin II, and taxinine NN-1 indicated stronger MDR cancer reversal activity than verapamil.
The result of primary screening based on 39 human cancer cell lines suggests that taxinine NN-1 belongs to a new mechanistic
class and is a new anticancer agents. 7-Epicephalomannine was found to be an effective anticancer agent with tubulin as its
molecular target, which is the same as paclitaxel.
Part of this work was presented at the 74th Annual Meeting of the Chemical Society of Japan, Tanabe, March 1998, and the 41st
Symposium on the Chemistry of Terpenes, Essential Oils, and Aromatics, Gifu, December 1998. The results of this work were
also presented as patent documents at PCT Int: Appl WO 2001007040 A1, February 2001; Appl WO 2000-Jp 5036, 27 July 2000. Priority:
JP 1999-214273, 28 July 1999; JP 1999-224652, 6 August 1999; JP 2000-76404, 14 March 2000 相似文献
196.
197.
Kazuhiko Maeta Ayumi Koike Hiroyuki Mukaiyama Tomoya Ochi Takao Terashita Yutaka Kitamoto Tadanori Aimi 《Journal of Wood Science》2008,54(4):337-340
In order to develop a novel method of obtaining monokaryons for a mycorrhizal fungus, Lyophyllum shimeji, monokaryotization of dikaryotic stock culture via protoplast formation and regeneration was performed using 12 dikaryotic
stocks. From 6 dikaryotic stocks, a total of 120 monokaryons were isolated, and their mating compatibility was tested. Mating-compatible
monokaryons were successfully derived from a dikaryotic stock (NBRC 100325), and monokaryons of only 1 mating type relative
to the parental dikaryons were isolated from another 3 strains (MH01710, OK2L-1, and HY7L-1). We successfully prepared monokaryotic
stocks via protoplast monokaryotization, a technique that can be used to identify biological species of L. shimeji. This technique could be used for breeding various mycorrhizal mushrooms, including Tricholoma matsutake, for which the preparation of monospore cultures is extremely difficult.
Part of this study was presented at the 11th Annual Meeting of the Japanese Society of Mushroom Science and Biotechnology
(Asahikawa), September 2007 相似文献
198.
Nahoko Nishi Tatsuro Muta Yoko Ito Masayuki Nakamura Takao Tsukiboshi 《Journal of General Plant Pathology》2009,75(1):80-82
A new disease of chrysanthemum causing ray speck was found in Okinoerabu island, Kagoshima, Japan in March 2006. Small reddish-brown
lesions were observed on the ray florets of the chrysanthemum (cv. Anastasia). The causal fungus was exclusively isolated
from the lesions, and typical symptoms were reproduced after inoculation with the isolate. The causal fungus was identified
as Stemphylium lycopersici (Enjoji) Yamamoto based on morphology and the sequences of rDNA-ITS and the gpd gene regions. The name, “sho-hanten-byo”, in Japanese is proposed for this ray speck disease. 相似文献
199.
Koito Tomoko Nakamura-Kusakabe Ikumi Yoshida Takao Maruyama Tadashi Omata Tamano Miyazaki Nobuyuki Inoue Koji 《Fisheries Science》2010,76(2):381-388
Seawater around deep-sea hydrothermal vents and cold seeps contain high levels of hydrogen sulfide, which is toxic to most
animals. Invertebrates inhabiting these environments have been reported to accumulate high levels of thiotaurine, a sulfur-containing
amino acid. Thiotaurine is likely to play an important role in sulfide detoxification, but its functions in the detoxification
process are still unknown. We cloned methane-seep mussel Bathymodiolus platifrons cDNA encoding the taurine transporter (TAUT), which transports thiotaurine and its precursors across the cell membrane. Phylogenetic
analyses revealed that the predicted peptide formed a clade with the TAUTs of shallow-water mussel Mytilus galloprovincialis and the hydrothermal vent mussel Bathymodiolus septemdierum that harbors thioautotrophic bacteria. We then reared B. platifrons in the presence or absence of Na2S and quantified TAUT mRNA using a real-time PCR system. The amount of TAUT mRNA in the gills of B. platifrons increased with rearing in the presence of Na2S for 69 days, but no change was observed in the absence of sulfide. These results suggest that TAUT plays an important role
in sulfide detoxification, even in species that do not harbor thioautotrophic bacteria. The TAUT mRNA level was variable in
the mantle and low in the foot throughout the entire rearing period, regardless of the presence/absence of sulfide, suggesting
that TAUT gene expression is regulated differentially in each tissue. 相似文献
200.
Jeong-Hoon Lee Keita Kodama Gen Kume Masaaki Oyama Satoshi Katayama Yuji Takao Toshihiro Horiguchi 《Fisheries Science》2009,75(2):379-385
To find an appropriate method for age determination in the marbled sole Pseudopleuronectes yokohamae in Tokyo Bay, Japan, sagittal otoliths of 1,343 individuals were observed by surface-reading and cross-section methods and
the results were compared. Opaque zones occurred once a year and were regarded as annuli in both methods. The surface-reading
method sometimes provided a lower count of the number of annuli than the cross-section method, and the frequency of this discrepancy
was highest in older fish (males above 5 years, females above 4 years). The oldest female fish was estimated to be age 10 years
by the cross-section method but 8 years by the surface-reading method. The cross-section method could provide a more accurate
estimate of age and is therefore likely to be indispensable to estimations of longevity. In contrast, the surface-reading
method is superior in terms of cost and time efficiency but is likely to underestimate the ages of older fish. However, growth
equations based on age estimated by the surface-reading method were sufficiently accurate if males ≥5 years and females ≥4 years
were combined as specific, single age groups of 5+ and 4+, respectively. 相似文献