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81.
We investigated the impact of high solar irradiance and elevated temperature on carbon gain by two, co-occurring, sun-adapted, dwarf shrub species, Planchonella obovata var. dubia (Koidz.) Hatusima and Hibiscus glaber Matsumura, growing on sun-exposed ridges in the Bonin Islands, in the subtropical Pacific Ocean. Planchonella had steeply inclined, longer lived, sclerophyllous leaves, whereas Hibiscus has thinner, more horizontally oriented, and shorter lived leaves. We tested the hypothesis that leaf physiological tolerance to high light is lower in Planchonella than in Hibiscus. Under relatively high irradiances (photosynthetic photon flux density, PPFD, > 500 micromol m(-2) s(-1)), net photosynthetic rate (P(n)) was about 8.0 and 0.4 micromol m(-2) s(-1) in mature and young leaves of Planchonella, and about 12.4 and 10.3 micromol m(-2) s(-1) in mature and young leaves of Hibiscus, respectively. Both P(n) and photosystem II (PSII) quantum yield at a given PPFD were lower in Planchonella than in Hibiscus, whereas non-photochemical quenching (NPQ) at a given PPFD was higher in Planchonella. When leaf discs were exposed to high light (1900 micromol m(-2) s(-1) PPFD) at 37, 40 or 43 degrees C for 3 h, the recovery of PSII quantum yield (F(v)/F(m)) in the following 60-min dark period was slower in Planchonella than in Hibiscus, indicating that the ability of PSII to tolerate high light and high temperature was less in Planchonella than in Hibiscus. We postulate that there is a linkage between leaf display and leaf photochemical ability in sun-adapted shrub species. 相似文献
82.
The spectral data of a new triterpene, cucurbita-5,23-diene-3beta,25-diol, isolated from the seeds of Sicana odorifera, are reported. 相似文献
83.
To quantify the nitrogen (N) use by Pinus densiflora trees growing on an infertile lava surface, N pools, N requirement and N uptake through fine roots and N deposition from the atmosphere were estimated. The N requirement and the N uptake of fine roots were 55.5kgNha–1year–1 and 39.7kgNha–1, respectively. Thus, the ratio of N uptake to N requirement of the fine roots was 71.5%. Including fine-root contribution, the total N requirement of the P. densiflora trees was 98.6kgNha–1year–1, and the total N uptake was 64.2kgNha–1year–1. Thus, the N uptake of the P. densiflora trees was 64.1% of the N requirement, indicating that P. densiflora trees growing on an infertile lava surface obtain some of their N from below-ground organic material layers every year and the contribution of N storage in trees for their growth is not any higher than indicated in previous reports that excluded fine-roots contribution. The wet N deposition of our research forest was only 5.8% of the N requirement of the P. densiflora trees and only 8.9% of the N uptake. Movement of the below-ground organic material layer N concentrations in the F- and L-layers coincides with needle development and fine-root growth, suggesting the possibility that P. densiflora trees extract N from the organic N of those layers for growth. 相似文献
84.
Kano R Okabayashi K Nakamura Y Fujiwara K Hasegawa A Sasaki Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(1):95-96
This report deals with three additional canine cases of sterile panniculitis treated by oral administration of tacrolimus and prednisolone. The oral tacrolimus treatment was proved to be an affordable medical protocol for canine sterile panniculitis with good efficacy and without adverse effects. 相似文献
85.
Takashi?Nakatsuka Misa?Saito Yuka?Sato-Ushiku Eri?Yamada Takashi?Nakasato Nobue?Hoshi Kazumichi?Fujiwara Takashi?Hikage Masahiro?NishiharaEmail author 《Euphytica》2012,184(3):335-344
We developed molecular markers for discrimination of white and blue flower color in Japanese gentian plants. White-flowered
gentians can be classified into two types, based on genetic and physiological features. One type includes four allelic variations
(gtmyb3-1, gtmyb3-2, gtmyb3-3, and gtmyb3-4) of an anthocyanin biosynthetic regulator gene (GtMYB3), distinguished by three PCR-based molecular markers. The other type contains a newly identified inactive allele (ans1) of the anthocyanidin synthase (ANS) gene with a premature stop codon generated from a 4-bp deletion in the second exon. The ans1 allele was distinguished from the active ANS allele by a cleaved amplified polymorphism sequence (CAPS) marker. The genotypes of 12 white-flowered gentian cultivars/lines
could be identified and classified as either ans1 or gtmyb3 using these four molecular markers. No white-flowered gentians contained ans1 and gtmyb3 alleles simultaneously. The mutated ANS gene co-segregated with white flower color in an F2 population, demonstrating that the CAPS marker is useful to discriminate between white and blue flowers in gentian. Markers
to discriminate flower color in Japanese gentian will be useful for early selection of progeny and for breeding management. 相似文献
86.
Masanao Yokohira Yuko Nakano Nozomi Hashimoto Keiko Yamakawa Fumiko Ninomiya Sosuke Kishi Kousuke Saoo Katsumi Imaida 《Journal of toxicologic pathology》2012,25(4):257-263
In vivo, nicotine in cigarette smoke induces various effects not only on the
respiratory system but also the central and peripheral nerve systems, circulatory organs and
digestive organs, and there is a possibility of promotion of lung tumorigenesis. The present
experiment was conducted to examine histopathological changes caused by nicotine in the lung
with repeated intratracheal instillation (i.t.). Six-week-old male F344 rats were administered
nicotine by i.t. at doses of 0.05, 0.1 and 0.2 mg nicotine/rat every 3 weeks beginning at week
4, for up to a total of 9 times and were then sacrificed at week 30. The total number of
administrations, total dose of nicotine and effective number of rats were 9 times, 0.45 mg and
5 rats and 4 times, 0.20 mg and 5 rats for the 0.05 mg nicotine/rat group; 3 times, 0.30 mg and
5 rats and 4 times, 0.40 mg and 3 rats for the 0.1 mg group; and 3 times, 0.60 mg and 3 rats
for the 0.2 mg group, respectively. As a control group, 5 rats were administered 0.2 ml
saline/rat 9 times. Some rats administered 0.1 and 0.2 mg nicotine suffered convulsions just
after administration. Histopathologically, though proliferative changes were not observed,
neutrophil infiltration, edema and fibrosis in the lung were induced by nicotine. In
conclusion, repeated treatment of nicotine promoted neurologic symptoms in the acute phase, and
strong inflammation in the lungs in the chronic phase, even at a low dose. Toxicity of nicotine
is suggested to depend not on total dose of nicotine in the experiment but rather on repeated
injury with consecutive administration. 相似文献
87.
88.
89.
Kitai S Shimizu A Kawano J Sato E Nakano C Kitagawa H Fujio K Matsumura K Yasuda R Inamoto T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):269-274
A total of 444 samples of raw chicken meat (thighs, breasts, wings, livers, gizzards, hearts and ovaries) that retailed at 145 different supermarkets in 47 prefectures in Japan were examined for contamination with Staphylococcus aureus in association with its enterotoxigenicity. S. aureus was isolated from 292 (65.8%) of the samples, and from 131 of the 145 supermarkets. There was no significant difference in the detection rate of S. aureus according to the type of meat examined. About 80% of 714 isolates belonged to the poultry (57.1%) and human biotypes (22.1%). Seventy-eight (21.7%) of 360 isolates were enterotoxigenic and isolated from 78 samples in 53 supermarkets in 31 prefectures. Staphylococcal enterotoxins (SEs) produced were SEB (50 isolates), SEA (14), SEC (8), SED (2), SEA+SEB (2), and SEA+SEC (2). Most of the enterotoxigenic isolates belonged to the human and poultry biotypes, coagulase type VII, VIII or IV, and were lysed by phages of group III. Identical SE types, biotypes, coagulase types and pulsed-field gel electrophoresis (PFGE) patterns were shown in isolates from different types of meat at the same supermarket and from samples taken from different supermarkets in the same prefectures or in isolates from samples obtained from several different prefectures. Among the 50 SEB-producing isolates, 27 yielded three similar PFGE patterns that differed by only a few fragments, suggesting that they were closely related genetically. The three patterns were found in isolates of samples that retailed at 17 supermarkets in 11 prefectures, indicating that they may be disseminated among raw chicken meat in Japan. 相似文献
90.