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591.
Effects of food materials were investigated on removal of several kinds of thiols, sulfides, and disulfides, which arise from vegetables of Allium species during food preparation and eating. Methanethiol, propanethiol, and 2-propenethiol were captured by raw foods such as fruits, vegetables, and mushrooms or a mixture of their acetone powders and phenolic compounds. The odor of diallyl disulfide was remarkably reduced by kiwi fruit, spinach, cutting lettuce, parsley, basil, mushrooms, and, particularly, cow's milk, raw egg, boiled rice, and bovine serum albumin (BSA). This suggests that the removal of diallyl disulfide could be caused by a physical and chemical interaction between the disulfide and foods. Furthermore, milk and BSA captured propanethiol, 2-propenethiol, dipropyl sulfide, diallyl sulfide, dimethyl disulfide, and dipropyl disulfide very well. An enzymatic degradation of diallyl disulfide by spinach and asparagus was also observed. These results demonstrate that the deodorization with foods is achieved by multiple actions including physical and chemical interaction between volatile sulfur compounds and foods, enzymatic degradation of disulfides, and addition of thiols to polyphenolic compounds, catalyzed by polyphenol oxidases or peroxidases. 相似文献
592.
593.
Kurata R Adachi M Yamakawa O Yoshimoto M 《Journal of agricultural and food chemistry》2007,55(1):185-190
Sweetpotato leaves (Ipomoea batatas L.) contain a high content of polyphenolics that consist of caffeic acid, chlorogenic acid, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, and 3,4,5-tri-O-caffeoylquinic acid. We investigated the suppression of the proliferation of selected human cancer cells by phenolic compounds isolated from sweetpotato leaf. The human cancer cells used in this research included a stomach cancer (Kato III), a colon cancer (DLD-1), and a promyelocytic leukemia cell (HL-60). Caffeic acid and di- and tricaffeoylquinic acids dose-dependently depressed cancer cell proliferation, and the difference in sensitivity between caffeoylquinic acid derivatives and each kind of cancer cell was observed. Specifically, 3,4,5-tri-O-caffeoylquinic acid effectively depressed the growth of three kinds of cancer cells, and caffeic acid had an exceptionally higher effect against HL-60 cells than other di- and tricaffeoylquinic acids. In attempting to clarify the mechanism of growth suppression with the addition of the apoptotic inhibitor N-ethylmaleimide, we observed that the nuclear granulation in 3,4,5-tri-O-caffeoylquinic acid-treated HL-60 cells suggested apoptosis induction. This effect was confirmed by DNA fragmentation, an increase of caspase-3 activity, and expression of c-Jun. Growth suppression of HL-60 cells by 3,4,5-tri-O-caffeoylquinic acid was determined to be the result of apoptotic death of the cells. These results indicate that 3,4,5-tri-O-caffeoylquinic acid may have potential for cancer prevention. 相似文献
594.
Watanabe T Tokishita S Spiegelhalter F Furui S Kitta K Hino A Matsuda R Akiyama H Maitani T 《Journal of agricultural and food chemistry》2007,55(4):1274-1279
In 2005 it was reported that the genetically modified (GM) maize strain or "event" called Bt10 had been distributed inadvertently in the United States over the previous 4 years. In order to ensure that grain for food and feed production did not contain trace amounts of Bt10 maize and complied with the applicable regulation, highly sensitive and specific detection of Bt10 maize was required. Accordingly, we developed a novel qualitative PCR system for specific detection of Bt10 maize. Moreover, we amply evaluated the performance characteristics of two PCR systems, our own and the one provided by the developer of Bt10, Syngenta Co. Ltd. It was confirmed that both of the qualitative PCR systems can specifically detect Bt10 maize, and the results of a single-laboratory examination suggested that the limit of detection was approximately less than 0.05% for both methods. To evaluate the reproducibility of the methods, we organized an interlaboratory study with the participation of 6 laboratories and analysis of 240 blind test samples. In this paper, we report, for the first time, the statistical analysis of the qualitative PCR data obtained from the interlaboratory study. The results of this analysis also revealed that there was no significant difference in the sensitivity between the two aforementioned methods and that the limit of detection of both the methods was less than 0.05%. Thus, we conclude that both of the methods are equally suitable for correct identification and sensitive detection of the unapproved GM maize Bt10 event in test samples. 相似文献
595.
596.
Soil humus plays a significant role in the cation exchange of a soil. YOSHIDA (1) showed that, as a general rule, divalent ions such as calcium and magnesium were adsorbed more strongly onto humus than monovalent ions such as ammonium and potassium in an ion-exchange reaction. He did not, however, describe the behavior of heavy metal ions. BREMNER et al. (2) first suggested that soil organic matter forms complexes with polyvalent cations. HIMES and BARBER (3) found that soil organic matter reacts with divalent metal ions in a manner similar to the chelation reaction. Reviews of the soil organic matter-metal complex have been written by BREMNER et al. (2) and KAWAGUCHI, MATSUO and KYUMA (4). 相似文献
597.
Keiichiro Matsuda 《Soil Science and Plant Nutrition》2013,59(5):202-206
In the previous paper (1), the author reported that when zinc sulfate and zinc-EDTA were added to soils, the percentage of exchangeable zinc, which has a lower degree of adsorption strength, to the total zinc adsorbed was higher in mineral soils, and the percentage of chelated zinc, which has higher degrees of adsorption strengths, was higher in humic soils. and that the percentage of chela ted zinc increased with the progress of humification in humic soils. 相似文献
598.
Toru Matoh Akira Matsuda Ryo Akaike Yoshitaka Hara Masaru Kobayashi 《Soil Science and Plant Nutrition》2013,59(4):779-784
Swiss chard plants were water-cultured under various B levels ranging from 0.01 to 20 g B m-3 culture solutions for 4 weeks. The B content of the shoot increased with the increase in the B supply. The increase, however, was entirely ascribed to acetate buffer (20 mol m-3 pH 4.0)-soluble B, and the content of acetate buffer-insoluble, cell wall-bound B did not increase.. More than ca. 80% of the cell wall-bound B was associated with rhamnogalacturonan II under various B levels. The amount of acetate buffer-soluble B could be estimated from the B levels in the expressed leaf sap. 相似文献
599.
Deng H Grunder S Cordova KE Valente C Furukawa H Hmadeh M Gándara F Whalley AC Liu Z Asahina S Kazumori H O'Keeffe M Terasaki O Stoddart JF Yaghi OM 《Science (New York, N.Y.)》2012,336(6084):1018-1023
We report a strategy to expand the pore aperture of metal-organic frameworks (MOFs) into a previously unattained size regime (>32 angstroms). Specifically, the systematic expansion of a well-known MOF structure, MOF-74, from its original link of one phenylene ring (I) to two, three, four, five, six, seven, nine, and eleven (II to XI, respectively), afforded an isoreticular series of MOF-74 structures (termed IRMOF-74-I to XI) with pore apertures ranging from 14 to 98 angstroms. All members of this series have noninterpenetrating structures and exhibit robust architectures, as evidenced by their permanent porosity and high thermal stability (up to 300°C). The pore apertures of an oligoethylene glycol-functionalized IRMOF-74-VII and IRMOF-74-IX are large enough for natural proteins to enter the pores. 相似文献
600.
Watanabe O Ogino M Iwamoto A Akiyama T Miki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(5):575-582
From April 1994 to March 2001, monitoring tests (surveillance) for contamination of Salmonella Enteritidis (SE) at commercial egg farms and farm traceback inspections for cases of SE foodborne illness were carried out in the Himeji Livestock Hygiene Service Center jurisdiction of Hyogo Prefecture, Japan. SE vaccination was not performed before the outbreak of SE-associated foodborne illness, and SE contamination of a farm was recognized. In the surveillance, the year average percentages of identified SE-positive farms were 6.1% in farms with floor feeding in an open-type henhouse (F-OH) and 12.7% in farms with cage feeding in a windowless-type henhouse (C-WH), but 0% in farms with only cage feeding in an open-type henhouse (C-OH). The highest identified proportion of SE-positive farms among all styles of farms was found (4.3%) in April 1997-March 1999. Farm traceback inspections were performed in 2 of 7 farms feeding by F-OH and in 5 of 9 farms feeding by C-WH in this period. Easier contamination with SE was found for C-WH or F-OH than for C-OH. Ninety percent of the birds (3,632,000 birds at 70 farms) are fed at these easier contamination farms by C-WH (89% of birds in 13% of farms) or F-OH (1% of birds at 10% of farms). Integrated sanitary requirements and SE vaccinations are especially necessary on farms feeding by F-OH or C-WH. Since 1999, these countermeasures have been performed, and SE foodborne illnesses and affected patients in Hyogo Prefecture have gradually decreased. 相似文献