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991.
Tanaka Hiroshige Nakagawa Toru Yokota Takashi Chimura Masayuki Yamashita Yuuho Funamoto Tetsuichiro 《Fisheries Science》2019,85(6):901-911
Fisheries Science - Reproductive characteristics under different water temperature regimes were examined in hatchery-reared walleye pollock Gadus chalcogrammus. The fish had been cultured for... 相似文献
992.
Masuda Yoshitsugu Shima Yasuhiro Tamaru Osamu Takahashi Yuki Ohmura Yoshihiro Iwasaki Takashi Kamoshida Masaaki Arimoto Misao Yamano Keisuke Yatabe Takashi 《Fisheries Science》2019,85(6):1045-1054
Fisheries Science - Morphological deformities of the jaw and vertebrae arise as hindrances to seed production of Japanese eel Anguilla japonica. To obtain basic information related to development... 相似文献
993.
We investigated the origin of dissolved free amino acids (DFAA) in stream water focusing on biofilms in the river bed by means
of incubation experiments in the laboratory. Stones were placed in the Toyohira River, Hokkaido, Japan, for 3 months, allowing
formation of biofilms, and then incubated for 24 h in the laboratory at stream water temperature. After incubation, the composition
and concentrations of DFAA in the incubation solution and total hydrolyzed amino acids (THAA) in biofilms were measured by
high-performance liquid chromatography. The amount of chlorophyll a (Chl. a) and the number of bacteria were also measured. The DFAA concentration increased greatly in the biofilm incubation solution,
but the DFAA composition (mol %) did not change relative to the inception of incubation, where it was similar to stream water.
There was no correlation between the increase in DFAA concentration and the THAA concentration, Chl. a amount, or the number of bacteria in biofilms. These results suggest that biofilms are one of the major sources of DFAA in
stream water. 相似文献
994.
Yoichi Miyake Shingo Kimura Tomohiko Kawamura Takashi Kitagawa Motoyuki Hara Hiroshi Hoshikawa 《Fisheries Science》2010,76(4):561-570
Most juveniles of Haliotis discus hannai have been found to be descendants of wild individuals, although most adults were artificially produced (released) individuals
as a result of restocking inside the refugium located near the head of Oshoro Bay, Hokkaido, Japan. To estimate the larval
supply from released and wild individuals into the refugium and to compare the suitability of locations as larval sources,
we simulated larval dispersal using a coupled hydrodynamic and particle-tracking model. The simulation results indicated that
more larvae may be supplied from the wild adults inside the bay to the refugium than from the released adults. These results
are consistent with the observed high abundance of wild juveniles in the refugium. Most larvae from the refugium were predicted
to disperse out of the bay. We found that larval retention in the bay was at least one order of magnitude higher than that
in the refugium. Thus, it may be more effective in terms of self-replenishment and reproduction if the refugium were to be
expanded to the bay scale. There were only minor differences among the compared sites at the head of the bay in terms of their
suitability as larval sources. Consequently, the establishment of new refugia in this area could be expected to provide an
effectiveness equal to that of the current refugium. 相似文献
995.
Yukiko Maruji Momoko Shimizu Michiyo Murata Masashi Ando Morihiko Sakaguchi Takashi Hirata 《Fisheries Science》2010,76(3):521-528
Boiled muscle extracts obtained from yellowtail Seriola quinqueradiata and bastard halibut Paralichthys olivaceus were treated with two kinds of purified enzymes (acid phosphatase and glutamate decarboxylase), and the change in contents
of nucleotides, related compounds, and free amino acids was examined. The change in taste qualities was also investigated
by a taste test. The enzyme treatment resulted in a marked decrease in the contents of such umami substances as inosine 5′-monophosphate
(IMP) and glutamic acid (Glu). The taste test revealed that the treatment of these fish muscle extracts with both or either
of the enzymes caused a sharp decrease in umami intensity and also an increase in sourness but not a change in pH. The treatment
also effected marked decreases in thickness and overall taste intensity. These findings suggest that IMP and Glu function
not only to intensify the thickness and overall taste as well as the umami, but also to repress the sourness sensation elicited
by the fish muscle extracts. 相似文献
996.
da Silva Edson Cabral Muraoka Takashi Bastos Alefe Viana Souza Franzini Vinícius Ide Buzetti Salatiér Soares Frederico Antonio Loureiro Teixeira Marconi Batista Bendassolli José Alberto 《Journal of Crop Science and Biotechnology》2020,23(3):289-289
Journal of Crop Science and Biotechnology - Due to an unfortunate oversight the author’s name and affiliation have been given erroneously. It should be read: 相似文献
997.
WanXue Bao Takuya Nagasaka Shin Inagaki Sho Tatebayashi Iori Imazaki Shin-ichi Fuji Takashi Tsuge Masafumi Shimizu Koji Kageyama Haruhisa Suga 《Plant pathology》2020,69(5):901-910
Fusarium fujikuroi, the causative agent of bakanae disease in rice, produces many kinds of secondary metabolites. Recently, two phylogenetic subgroups (F and G groups) of Japanese F. fujikuroi have been identified and found to have differences in their gibberellin (GA) and fumonisin production. G-group F. fujikuroi produces large amounts of GA, but is a fumonisin nonproducer. F-group produces large amounts of fumonisin, but is a GA low or nonproducer. We investigated the cause of low GA production in the F-group. Genetic mapping suggests that low GA production in the F-group strain Gfc0825009 is due to a GA gene cluster for GA biosynthesis. Analysis of the nucleotide and amino acid sequences of the genes in the GA gene cluster showed >98.4% homology between the F-group strain Gfc0825009 and the G-group strain Gfc0801001. Following a 7-day culture under low nitrogen conditions, we found that expression of P450-1, P450-4, and P450-2 in the cluster increased in the G-group strain and not in the F-group strain. We hypothesized that complementation by GA genes in the G-group strain would be required to increase GA production in the F-group strain. However, we found that this occurred with a single gene complementation of DES, P450-1, P450-4, or P450-2. Simultaneous increase in the expression of P450-1, P450-4, and P450-2 were detected in the complementary transformants. Moreover, the same phenomenon was observed by reintegration of its own P450-1. Our results suggest the presence of unknown regulatory mechanisms of the GA gene cluster in F. fujikuroi. 相似文献
998.
Chensom Sasicha Shimada Yasuhito Nakayama Hiroko Yoshida Kumi Kondo Tadao Katsuzaki Hirotaka Hasegawa Sachiko Mishima Takashi 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):265-271
Plant Foods for Human Nutrition - Titanbicus (TB), a hybrid of Hibiscus moscheutos × H. coccineus (Medic.) Walt., has potential to be used as an edible flower. In this study, proximate... 相似文献
999.
Taku Kato Takashi Kamijo Tamao Hatta Kenji Tamura Teruo Higashi 《Soil Science and Plant Nutrition》2005,51(2):291-301
In the initial soil formation processes of the Volcanogenous Regosols (Scoriacious) from Miyake-jima Island, Japan, the soil profile morphology showed a distinct formation of the A horizon, about 10 cm thick, over C horizons during a period of 125 years. Along with these soil formation processes under the primary succession of vegetation from bare land to mixed forest, the following changes in the soil characteristics were observed of four study sites where soil formation had occurred over a period of 16, 38, 60 and 125 years in scoriacious volcanic materials ejected during each eruption. Whole soil samples of the surface horizon showed that the proportion of the > 2mm fraction decreased and the clay fraction increased. Electron microscopic observation revealed that pores on the scoria surface were newly formed and had expanded with advanced weathering, and that the formation of a weathering zone on the scoria surface (polygonal shape) was more recognized with the passage of time. Soil pH of the surface horizon decreased, and the amount of carbon in the surface samples showed a linear increase with the passage of time. The amounts of exchangeable bases and the CEC value of the surface samples showed comparable increase rates with time. Consequently, the base saturation percentage was kept at about 100% during the 125-year period. It was suggested that the increase in the amounts of exchangeable bases was controlled by the increase in the amounts of soil organic matter accumulated during the initial soil formation processes of Volcanogenous Regosols (Scoriacious). 相似文献
1000.