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991.
Takashi Yokota Hiromichi Mitamura Nobuaki Arai Reiji Masuda Yasushi Mitsunaga Masashi Itani Hiroyuki Takeuchi Tatsuo Tsuzaki 《Fisheries Science》2006,72(3):520-529
ABSTRACT: In order to establish techniques for the stock enhancement of red tilefish Branchiostegus japonicus , it is important to understand the behavioral characteristic of both hatchery-reared and wild fish. Four hatchery-reared and six wild fish were released and tracked using acoustic biotelemetry in Maizuru Bay, Kyoto, Japan, from August 2003 to February 2004. Data for the four wild fish released and tracked from January 2003 to May 2003 were also referred to for analysis. The released fish moved around in relatively large areas within about 10 days after the release, and then three hatchery-reared and two wild fish settled and stayed within limited areas. Fish of both origins showed strong site fidelity and diel activity patterns, i.e. they were detectable in the day but not at night, probably due to hiding behavior in their burrows at night. However, some discrepancies between fish of both origins were detected by comparing their track terms and activity patterns in detail. These discrepancies are probably attributable to the differences in environmental conditions that the fish had experienced before release. 相似文献
992.
Hiromichi?MitamuraEmail author Nobuaki?Arai Yasushi?Mitsunaga Takashi?Yokota Hiroyuki?Takeuchi Tatsuo?Tsuzaki Masashi?Itani 《Fisheries Science》2005,71(3):491-498
ABSTRACT: Wild red tilefish Branchiostegus japonicus were tracked and/or monitored for up to nearly 3 months in Western Wakasa Bay and Maizuru Bay, Japan, using ultrasonic telemetry to examine their movements and burrow fidelity patterns. In Western Wakasa Bay, it is guessed that fish released in relatively shallow waters, about 30 m deep, actively moved into more suitable deeper habitats after their release. In Maizuru Bay, the fish did not undertake large-scale movements and showed burrow fidelity about 1 month after their release. That is, the fish primarily remained in the burrow, which was constructed in the sea-bottom, during the night and moved outside the burrow during the day. The marked circadian rhythm from Fourier analysis indicated a clear diel movement pattern of the red tilefish. 相似文献
993.
Maria R. M. Coimbra Kazunobu Kobayashi Shinrokuro Koretsugu Osamu Hasegawa Eriko Ohara Akiyuki Ozaki Takashi Sakamoto Kyoshi Naruse Nobuaki Okamoto 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):203-218
We report the first genetic linkage map of the Japanese flounder (Paralichthys olivaceus) constructed with 111 microsatellite markers and 352 AFLP fragments. The parental male linkage map consisted of 25 linkage groups while the female map consisted of 27 groups, with an average resolution of 8 and 6.6 cM, respectively. We have identified linkage among 96% of the markers and the total map length was estimated to be around 1000–1200 cM. This study reports the first low-density linkage map for the Japanese flounder and describes differences in sex recombination. Recombination rates were higher in male flounder compared to the female (7.4:1), a rare condition among vertebrates. This map is a starting point for the mapping of single loci and quantitative traits in flatfish species. 相似文献
994.
Investigations were conducted on the flathead flouder Hippoglossoides dubius to analyze the environmental conditions around the spawning grounds and the maturational status of spawners in the Sea of
Japan off Niigata. In both sexes, larger fish matured earlier than smaller individuals, and participated in breeding from
the early part of the spawning season. Males were always the predominant sex found within the spawning ground, likely because
males spent longer periods in the spawning grounds than females. This finding further suggests that males matured earlier
and maintained sexual activity for longer periods than females within the spawning grounds. Submarine topography and water
temperature were concluded to be important factors affecting the formation of the spawning grounds. The spawning ground was
located within a restricted area where bathymetric lines curve towards a shallow area. Adult fish usually occur in the Japan
Sea Proper Water (<1 °C), but spawners gathered just below the surface mixing layer where water temperature was 5–10°C. Hence,
it was thought that the flounder spawn at the upper tolerable water temperature limit (i.e. the shallowest accessible depth)
to release their offspring into the surface layer. 相似文献
995.
This survey was conducted from 2005 to 2008 regarding the thermal environment of three types of experimental houses—a wood and mud composite wall type (Type WM), a mud wall type (Type M), and an insulated wall type (Type I). To reveal the influence of the wall composition of wooden houses on the indoor thermal environment, each experimental house was constructed on the same site. As a result, under natural indoor air temperatures, the monthly average indoor air temperature level and the time ratio of indoor air temperature surpassing the outdoor air temperature were in the following order: Type I > Type WM > Type M. Type WM exhibited the highest phase shift of air temperature, indicating that the insulation performance and heat capacity affect the phase shift of air temperature. The equalization of indoor air temperature through the suppression of the increase in the indoor air temperature of Type M is likely caused by low insulation performance and large thermal capacity. The time fluctuations in electric consumption by air conditioning and indoor–outdoor air temperature differences of each experimental house over 1 day indicated that a building’s thermal load and the thermal capacity are related. 相似文献
996.
Influence of Hatchery Protocols on Mitochondrial DNA Variation in Japanese Flounder Juveniles 总被引:1,自引:0,他引:1
Takashi Asahida Yumi Shinotsuka Unji Saitoh Yoh Yamashita Hitoshi Ida Ken-Ichi Hayashizaki 《Journal of the World Aquaculture Society》2003,34(2):121-132
The Japanese flounder Paralichthys olivaceus is a commercially important fish that is stocked extensively from hatchery rearing programs in Japan. To examine the genetic variability of hatchery-raised juveniles of the Japanese flounder that are used for stocking into natural waters, we analyzed a portion of the mitochondrial genome. The mtDNA region extending from the 3'half of the cytochrome b gene to the central domain of the control region was PCR amplified and analyzed using 11 restriction endonucleases. We identified 34 polymorphic cleavage sites out of a total of 61 sites, which resulted in 67 different haplotypes in a total of 265 offspring, examined from eight hatchery stocks. Haplotype diversity of offspring at each of the eight hatcheries ranged from 0.49 ± 0.09 (SE) to 0.94 ± 0.03 (SE). Also, we observed 40 polymorphic sites out of a total of 59 sites, which resulted in a total of 50 haplotypes in 60 wild flounder. Haplotype diversity of the wild population was 0.98 ± 0.01 (SE). The use of subcultured fishes as broodstock appears to be one of the most important causes of reduced genetic diversity in hatchery-raised flounder juvenile. Our results suggest that the use of wild fish for broodstock is an effective way to maintain genetic variability in Japanese flounder offspring. 相似文献
997.
Soil erosion in agricultural fields affects not only land productivity but also water environment down stream. Many investigations
have been made for the prediction of soil erosion processes. The Universal Soil Loss Equation (USLE) has been applied broadly
for the prediction of average annual soil loss from upland fields. However, there are few reports concerning the prediction
of nutrient (N, P) losses based on the USLE. Thus, the objective of this study is to propose the prediction equation of nitrogen
and phosphorus losses during soil erosion processes on the basis of the USLE. In order to predict total nitrogen and phosphorus
losses, the coefficients for total nitrogen or phosphorus transfer are derived on the basis of results from experimental field
plots. Three bare-cover USLE plots with different amounts of granular chemical fertilizer were installed in an experimental
upland field. There was a tendency for the coefficient of total nitrogen or phosphorus transfer to increase with the average
concentration of total nitrogen or phosphorus in the soils. It follows that the more granular chemical fertilizer applied
caused a higher coefficient of total nitrogen or phosphorus transfer in the calculations. Moreover, the coefficients in heavily
fertilized plots were higher than 1.0. Through this investigation, it became clear that the nutrient losses during soil erosion
could be predicted on the basis of the coefficient of total nitrogen or phosphorus transfer along with other soil erosion
parameters. 相似文献
998.
Tatsuya Sugawara Ponesakki Ganesan Zhuosi Li Yuki Manabe Takashi Hirata 《Marine drugs》2014,12(6):3660-3668
Siphonaxanthin is a specific keto-carotenoid in green algae whose bio-functional properties are yet to be identified. This review focuses on siphonaxanthin as a bioactive compound and outlines the evidence associated with functionality. Siphonaxanthin has been reported to potently inhibit the viability of human leukemia HL-60 cells via induction of apoptosis. In comparison with fucoxanthin, siphonaxanthin markedly reduced cell viability as early as 6 h after treatment. The cellular uptake of siphonaxanthin was 2-fold higher than fucoxanthin. It has been proposed that siphonaxanthin possesses significant anti-angiogenic activity in studies using human umbilical vein endothelial cells and rat aortic ring. The results of these studies suggested that the anti-angiogenic effect of siphonaxanthin is due to the down-regulation of signal transduction by fibroblast growth factor receptor-1 in vascular endothelial cells. Siphonaxanthin also exhibited inhibitory effects on antigen-induced degranulation of mast cells. These findings open up new avenues for future research on siphonaxanthin as a bioactive compound, and additional investigation, especially in vivo studies, are required to validate these findings. In addition, further studies are needed to determine its bioavailability and metabolic fate. 相似文献
999.
Alinne da Silva Raffaella Rossetto Juliana Bombecini Michel Piemonte Takashi Muraoka 《Journal of plant nutrition》2014,37(8):1227-1236
Vinasse is a liquid residue applied as a fertilizer in sugarcane crops. However, in areas far away from sugarcane mills the cost of the distribution can be very high due, the large volume of water. So, one solution is to concentrate the vinasse by the evaporation process to reduce transport costs. Considering that the nitrogen mineralization kinetics is not known in concentrated vinasse, the objective of this study was to evaluate the net and potential nitrogen mineralization in soil that received vinasse concentrated and not concentrated. The treatments with concentrated vinasse provided the highest values of net mineralization and total nitrogen, which presented significant correlation each other, the same way as the potential mineralization values had a positive correlation with the doses and the amounts of total nitrogen. The total nitrogen values can be used as an index of nitrogen availability in soils that received concentrated vinasse. 相似文献
1000.
Norihito Yamauchi Mamoru Satou Jyuichi Shimazu Takashi Shirakawa Seizo Horiuchi 《Journal of General Plant Pathology》2007,73(1):29-34
Race 2 isolates of Fusarium oxysporum f. sp. lactucae have been recognized as biotin auxotrophs and consequently have restricted growth on Puhalla's minimal medium (MM), which
contains no biotin. Biotin-autotrophic isolates were raised from race 2 isolates through cultural mutation that grew as well
on MM as they did on MM supplemented with biotin. These autotrophs were identical to the parental isolates in pathogenicity
on race differential cultivars of lettuce (Patriot, Banchu Red Fire, and Costa Rica No. 4), and thus were designated as race
2. A vegetative compatibility test indicated that the autotrophic isolates fell into the same vegetative compatibility group
as the parents. Culture filtrates of the autotrophs allowed abundant growth of the parental auxotroph on MM, and, through
a competitive enzyme-binding assay, biotin was detected in the culture filtrates. These results suggest that biotin auxotrophy
in the natural race 2 isolates has no direct relation to pathogenicity, qualitatively defined as physiological race, or to
vegetative compatibility. 相似文献