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排序方式: 共有306条查询结果,搜索用时 187 毫秒
181.
Nolan V. Chalifoux Emmanuelle M. Butty Katie D. Mauro Rachel B. Moyle Caryn M. Ehrhardt James B. Robertson Mary A. Labato Christine A. Culler Leonel A. Londoño Alessio Vigani Yu Ueda Steven E. Suter Alex M. Lynch 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(1):161-172
182.
Ethanol was produced from the hydrolysate collected as the water-soluble (WS) portion after hot-compressed water (HCW) treatment
of Japanese beech. The process involved saccharification with β-xylosidase followed by isomerization with xylose isomerase and fermentation with Saccharomyces cerevisiae. Several process schemes were compared to investigate the effect of process integration of saccharification, isomerization,
and fermentation. Higher ethanol yields were obtained for the processes that integrated isomerization and fermentation or
saccharification and isomerization. Integration of isomerization and fermentation was effective in converting xylose into
ethanol. Similarly, integration of saccharification and isomerization was effective in converting xylooligosaccharides into
xylulose. It is presumed that the saccharification reaction toward xylose and the isomerization reaction toward xylulose were
linked and therefore each reaction was enhanced. 相似文献
183.
The initial step of nutrients uptake by plant roots is the physico-chemical process of the exchange and adsorption of nutrients to root surface. The properties of root's surface determining the nutrients adsorption and exchange on them are mainly the cation exchange capacity and intensity. The possible role of these properties in the nutrient uptake via roots will not be understood unless the nature of the cation exchange ability of roots is clarified. The authors reported the preliminary experimental results on cation exchange capacity of crop roots1). The present paper deals with the re-examination of the various procedures, applicable to the determination of C. E. C. of the various crop roots. Discussions on the importance of the intensity of bonding of cations were also made. 相似文献
184.
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
185.
Tulio AZ Yamanaka H Ueda Y Imahori Y Chachin K 《Journal of agricultural and food chemistry》2003,51(23):6774-6781
The reversible and irreversible emission of methanethiol (MT) and dimethyl disulfide (DMDS) from broccoli florets was demonstrated during anaerobic storage at 20 degrees C for up to 24 h. Reversible emission of MT and DMDS was feasible only in broccoli stored for between 0 and 12 h under entirely anaerobic condition. Beyond that, the emission was completely irreversible. This irreversible process was demonstrated through significant reductions in the chlorophyll fluorescence values and rate of carbon dioxide production and significant increase in the membrane permeability of induced broccoli tissues after exposure to air and incubation. Irreversible emission was also demonstrated through significant change in color from the characteristic bright green to olive green as well as the conversion of chlorophyll a to pheophytin a and chlorophyll a' contents of the induced florets after hot-water treatment. These findings suggest that the irreversible emission of MT and DMDS is a function of permanent membrane damage and loss of intracellular compartmentation in the broccoli tissues as a result of the anaerobic induction. The off-odor formation can still be reversed if the affected tissue is only temporarily impaired by anaerobic condition, thereby maintaining the quality of stored broccoli. 相似文献
186.
Tsutomu Hattori Yoji Narimatsu Masaki Ito Yuji Ueda Daiji Kitagawa 《Fisheries Science》2008,74(3):594-602
ABSTRACT: Body size dependent distribution patterns of bighand thornyhead Sebastolobus macrochir were examined using bottom trawl surveys in the Tohoku area, off the Pacific coast of northern Honshu, Japan. In northern and southern Tohoku, distribution depths of ≤10-cm standard length (SL) fish increased from 500–600 m in 2003 to 600–700 m in 2005 with an increase in density of 11–20-cm SL fish at depths of 500–600 m. In 2004–2005, small fish (≤10 cm SL) were distributed in deeper waters than large fish (11–20 cm SL). In ≤20-cm SL fish, the main distribution depths changed from 300–600 m in 1997–2002 to 500–600 m in 2003 in southern Tohoku, but not in northern Tohoku. Stepwise multiple regression analysis showed that negative correlations were found in biomass densities between a few demersal fish species and bighand thornyhead at depths of 300–400 and 400–500 m in southern Tohoku. These results suggest that distribution of bighand thornyhead was affected by intra- and interspecific competitions in the Tohoku area. 相似文献
187.
188.
Teruya Maki Hiroshi Hasegawa Hiroyuki Kitami Kyoko Fumoto Yukihiro Munekage Kazumasa Ueda 《Fisheries Science》2006,72(4):811-820
ABSTRACT: Antibiotic residues in marine sediments of fish farms negatively influence microbial ecologic systems. The microbial degradation of antibiotic residues was experimentally examined in the marine sediments of Uranouchi Bay, to which one of five antibiotics was added. After incubation reducing physical factors, ampicillin, doxycycline, oxytetracycline, and thiamphenicol were significantly degraded, while josamycin maintained most of the initial amounts. The isolates resistant to ampicillin, josamycin, oxytetracycline, or thiamphenicol degraded each antibiotic in wide ranges of degrees, whereas the isolates degrading doxycycline were not obtained. Microbial degradation may contribute to the disappearance of ampicillin, doxycycline, oxytetracycline, and thiamphenicol in the fish farm. In contrast, the disappearance of josamycin would depend on physical factors, but the bacteria degrading josamycin at least exist in the marine sediments. Phylogenetic analysis using 16S rDNA sequences demonstrated that the antibiotic-resistant isolates formed several clusters in the Gram-positive bacterial group, the Flavobacterium–Cytophaga–Bacteroides group, and the proteobacteria subdivisions. The antibiotic-resistant bacterial population would be composed of various species including ubiquitous coastal bacterial groups. Several species of antibiotic resistant bacteria show antibiotic degradation activities, and appear to contribute to the disappearance of antibiotics in Uranouchi Bay. 相似文献
189.
Gladys Wairimu Karugia Haruhisa Suga Liane Rosewich Gale Takashi Nakajima Akihisa Ueda Mitsuro Hyakumachi 《Journal of General Plant Pathology》2009,75(2):110-118
Genetic subdivision of Fusarium asiaticum was investigated using a collection of 478 isolates originating from the Kyushu area and Aichi Prefecture, Japan and Zhejiang
Province in China. Trichothecene-type determination by a multiplex PCR-test indicated that all isolates were either of a nivalenol
(NIV) or a 3-acetyl deoxynivalenol (3ADON) type. The 15-acetyl deoxynivalenol (15ADON) type was not detected in this collection.
Based on a Bayesian model-based clustering method using allele data obtained with 11 variable number of tandem repeats (VNTR)
markers, we detected three genetic clusters. The majority of isolates in the clusters were NIV isolates from both Japan and
China, Japanese 3ADON and Chinese 3ADON isolates, respectively. High levels of fixation indices and low levels of effective
number of migrants were observed between the genetic clusters. Data was re-analyzed by classifying the isolates into six groups
according to trichothecene type and geographic location. Population analyses of these re-classified groups indicated that
the genetic subdivisions of F. asiaticum were correlated with both trichothecene type and geographic differences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
190.
Carotenoids, one of the most common types of natural pigments, can influence the colors of living organisms. More than 750 kinds of carotenoids have been identified. Generally, carotenoids occur in organisms at low levels. However, the total amount of carotenoids in nature has been estimated to be more than 100 million tons. There are two major types of carotenoids: carotene (solely hydrocarbons that contain no oxygen) and xanthophyll (contains oxygen). Carotenoids are lipid-soluble pigments with conjugated double bonds that exhibit robust antioxidant activity. Many carotenoids, particularly astaxanthin (ASX), are known to improve the antioxidative state and immune system, resulting in providing disease resistance, growth performance, survival, and improved egg quality in farmed fish without exhibiting any cytotoxicity or side effects. ASX cooperatively and synergistically interacts with other antioxidants such as α-tocopherol, ascorbic acid, and glutathione located in the lipophilic hydrophobic compartments of fish tissue. Moreover, ASX can modulate gene expression accompanying alterations in signal transduction by regulating reactive oxygen species (ROS) production. Hence, carotenoids could be used as chemotherapeutic supplements for farmed fish. Carotenoids are regarded as ecologically friendly functional feed additives in the aquaculture industry. 相似文献