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排序方式: 共有321条查询结果,搜索用时 15 毫秒
101.
Jun Shoji Tsutomu Maehara Mitsuhiro Aoyama Hiroshi Fujimoto Akio Iwamoto Masaru Tanaka 《Fisheries Science》2001,67(2):238-245
SUMMARY: Diel successive samplings of Japanese Spanish mackerel Scomberomorus niphonius larvae were conducted throughout 24 h both in the sea and in captivity in order to estimate their daily ration. Using the Elliott and Persson model, the instantaneous gastric evacuation rate was estimated from the depletion of stomach contents (% dry bodyweight) with time during the night for wild fish (3.0–11.5 mm standard length) and from starvation experiments for reared fish (8, 10, and 15 days after hatching (DAH)). Japanese Spanish mackerel is a daylight feeder and exhibited piscivorous habits from first feeding both in the sea and in captivity. Feeding activity peaked at dusk. The estimated daily ration for wild larvae were 111.1 and 127.2% in 1996 and 1997, respectively; and those for reared larvae ranged from 90.6 to 111.7% of dry bodyweight. Based on the estimated value of daily rations for reared fish, the total number of newly hatched red sea bream Pagrus major larvae preyed by a Japanese Spanish mackerel from first feeding (5 DAH) to beginning of juvenile stage (20 DAH) in captivity was calculated to be 1139–1404. 相似文献
102.
An Hand von Bodenproben aus langjährigen Dauerdüngungsversuchen im Relsfeld wurden Untersuchungen über den Einfluβ der Kalkdüngung auf den Humusgehalt, die Humuszusammensetzung und den Koblenhydratgehalt durchgeführt, die folgende Ergebnisse brachten: Durch langjährige hobe Kalkdüngung wurde der Gehalt an organischer Bodensubstanz wesentlich herabgesetzt und dies um so stärker, je höher die Kalkmenge war, wobei die Erhöhung der pH-Werte parallel verlief. Aber bel der Kalkdüngung im praktisch angewandten Ausmaβe oder im etwas höheren Ausmaβe wurde der Gehalt an organischer Bodensubstanz unwesentlich verändert, obwohl es sich auch hler urn elne sebr langjährige Dauerdüngung handelt. Die langjährige hohe Kalkdüngung verändert sowohl den extrahierbaren Humusgehalt als auch die Humuszusammensetzung stark, wobei extrahierte Fulvosäure besonders stark abgenommen hat und der relative Fulvosäureanteil am Gesamthumus beträchtlich kleiner wurde. Eine absolute und relative Abnahme der Menge an gesamten und wasser-löslichen Kohtenhydraten wurde durch langjährige hohe Kalkdüngung festgeetellt. Es wird darauf hingewiesen, daβ die Kohlenhydrate in stärkerer Beziehung zu den Bestandteilen der Fulvosäure als zu denen der Huminsäure stehen. Der Einfluβ organischer Düngung zur Erhaltung der unter Kalkdüngung stehenden organischen Bodensubstanz wurde festgestellt. 相似文献
103.
Kubota S Miyaji K Shimo Y Shimakura H Takase Y Okamoto N Kiuchi A Fujimura M Fujimura T Deboer DJ Tsukui T Sakaguchi M 《Veterinary immunology and immunopathology》2012,149(1-2):132-135
The present study investigated IgE reactivity to a new Cryptomeria japonica pollen allergen (Cry j 3) in dogs with atopic dermatitis by using a fluorometric ELISA. Serum samples from 15 dogs that showed IgE sensitivity to crude C. japonica pollen allergen by ELISA were tested for specific IgE to each allergen, individually. All 15 dogs had anti-Cry j 1 IgE, 6 (40%) had anti-Cry j 2 IgE, and 11 (73%) had anti-Cry j 3 IgE. Further, we found that these anti-Cry j 3 IgE reacted to Cry j 3 with immunoblotting analysis. These findings indicate that Cry j 3 may be a major allergen in dogs. 相似文献
104.
Ken-ichiro Yamashita Hikaru Tsukazaki Akio Kojima Takayoshi Ohara Tadayuki Wako 《Euphytica》2010,173(3):357-367
Cytoplasmic male sterility (CMS) is an indispensable trait for F1 hybrid seed production in bunching onion (Allium fistulosum L.). Expansion of the cytoplasmic diversity of F1 hybrid cultivars by introduction of various CMS resources has great potential to eliminate vulnerability to cytoplasm type-specific
diseases. This study aimed to evaluate appearance frequency of male sterile plants in several bunching onion accessions and
to identify CMS resources. In eight (‘Nogiwa Aigara’, ‘Bansei Hanegi’, ‘Amarume’, ‘Kimnung’, ‘Zhangqiu’, ‘INT/CHN/1990/GOTOU’,
‘Natsunegi’ and ‘Guangzhou’) of 135 accessions collected from Japan, China, Mongolia, Korea and Taiwan, male sterile plants
appeared with varied frequencies from 1.7% (‘Nogiwa Aigara’ and ‘Bansei Hanegi’) to 24.5% (‘Zhangqiu’). The inheritance mode
of Zhangqiu- and Guangzhou-derived male sterility was confirmed to be CMS by sib-crossings and interbreed crossings. Microscopic
examination of microsporogenesis in the CMS plants revealed that microspore protoplasm rapidly degenerated without mitotic
division after the release of microspores from tetrads. The CMS germplasm described here would be useful for the development
of “A” lines to be used in F1 hybrid seed production of bunching onion. Male fertility in ‘Nogiwa Aigara’, ‘Bansei Hanegi’, ‘Kimnung’, ‘INT/CHN/1990/GOTOU’
and ‘Natsunegi’ was verified to be controlled by a single fertility restoration locus. 相似文献
105.
The effect of low reactive-level laser therapy (LLLT) with helium-neon laser on operative wound healing in a rat model 总被引:3,自引:0,他引:3
Yasukawa A Hrui H Koyama Y Nagai M Takakuda K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(8):799-806
The effect of low reactive-level laser therapy (LLLT) with a He-Ne laser on operative wound healing was investigated in a rat model. 10-millimeter surgical wounds were created on the backs of Sprague Dawley rats, and animals were assigned to one of eleven groups (n=5). Ten groups received either 8.5 mW or 17.0 mW irradiation of 15 seconds LLLT a day with one of five different irradiation frequencies, i.e. daily (from the 1st to 6th day following surgery), every other day (the 1st, 3rd, and 5th day), on only the 1st day, on only the 3rd day, and on only the 5th day; the 1st day was the day following the surgery. The control group received no irradiation. A skin specimen was harvested from the dorsal thoracic region on the 7th day to measure the rupture strength. The control group had the lowest rupture strength (5.01 N), and the 17.0 mW every other day irradiation group had the highest rupture strength (13.01 N). Statistical differences were demonstrated in the 8.5 mW irradiation setting between the every other day irradiation group and the control group (p<0.05); and in 17.0 mW irradiation setting between the every day irradiation, the every other day, and the 1st day only groups vs. the control group (p<0.01). Histological examination demonstrated that wound healing in the 17.0 mW every other day irradiation group was promoted most significantly such as the prevention of excessive inflammation, increased formation of collagen fibers, and recovery in continuity of tissues. The control group showed poor wound healing and the other experimental groups showed intermediate healing. Thus LLLT with a He-Ne laser was found to promote the healing of operative wounds in the present rat model, in which the most favorable application of LLLT was the 17.0 mW setting of 15 seconds a day with a frequency of every other day. 相似文献
106.
The role of tetrapartite associations among Frankia, Gigaspora margarita (an arbuscular mycorrhizal fungus), Pseudomonas putida (rhizobacterium), and Alnus sieboldiana in growth, nitrogen fixation, and mineral acquisition of A. sieboldiana was investigated. Seedlings of A. sieboldiana were inoculated with Frankia isolated from root nodules of alder, followed by inoculation of G. margarita and P. putida, and were grown for 5 months in a greenhouse. The seedlings inoculated with Frankia and G. margarita together produced the highest biomass of shoots and root nodules. Nitrogen-fixation activity, measured by acetylene reduction assay, was observed when Frankia was inoculated. The activity, on a per-nodule gram basis, decreased after G. margarita inoculation, but on a per-plant basis there was no significant difference in the activity among inoculation treatments. The mineral content in the seedlings changed after inoculation with Frankia, but not after inoculation with P. putida and/or G. margarita. The results showed a synergistic interaction among Frankia, the mycorrhizal fungus, and the rhizobacterium on the growth of A. sieboldiana. 相似文献
107.
Shohei Kaneko Katsuhiko Yoshitake Shuji Itakura Hiromi Tanaka Akio Enoki 《Journal of Wood Science》2005,51(3):262-269
The degradation of wood, filter paper cellulose, and a lignin-substructure model, was measured in cultures of seven fungi usually regarded as brown-rot fungi. Hydroxyl radical production and the accumulation of oxalic acid in the cultures were also measured. Four of the fungi, Gloeophyllum trabeum, Tyromyces palustris, Laetiporus sulphureus, and Postia placenta, were typical brown-rot fungi, in that they preferentially degraded and eliminated the polysaccharides in wood and produced large amounts of hydroxyl radical. The rates of hydroxyl radical generation in cultures of the four fungi were directly proportional to the degradation rates of wood, cellulose, and the lignin-related compound, and inversely proportional to the amount of oxalic acid in the cultures. Two of the fungi, Daedalea dickinsii and Lentinus lepideus, did not degrade any of the substrates significantly and produced very little hydroxyl radical. Coniophora puteana had the highest rate of cellulose degradation, but did not degrade wood or the lignin model significantly and produced only negligible amounts of hydroxyl radical. These results indicate that brown-rot fungi produce large amounts of hydroxyl radical for the degradation of wood and crystalline cellulose. 相似文献
108.
Shin-ichiro Tohmura Atsuko Ishikawa Kohta Miyamoto Akio Inoue 《Journal of Wood Science》2012,58(1):57-63
A mechanism of acetaldehyde emission from wood induced by the addition of ethanol was proposed. It is known that acetaldehyde
generation is due to the oxidation of ethanol via a metabolic process involving alcohol dehydrogenase (ADH) in living bodies.
However, it remains unclear whether the enzymatic alcohol oxidation is applicable to wood. We investigated possible factors
of wood parts, conditioning, storage sites, and heating and sterilization treatments on acetaldehyde emission using the syringe
method and HPLC analysis. We reconfirmed that acetaldehyde emission was observed only when ethanol was added to wood. Greater
acetaldehyde emissions were obtained in heartwood compared to sapwood in both Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.) specimens. In addition, an acetaldehyde conversion rate of 1–2 mol% was determined in green cedar heartwood samples,
while, conversely, air-dried cedar heartwood samples showed 4–5 mol%. Ethylene oxide gas sterilization had the effect of decreasing
acetaldehyde emission on air-dried wood, but not on green wood. Autoclave sterilization could completely prevent acetaldehyde
emissions from both green and air-dried wood. These results suggested that an original ADH in wood and an attached ADH from
the outside via microorganisms onto wood were assumed to be the primary causes of acetaldehyde emissions from wood induced
by the addition of ethanol. 相似文献
109.
We derive a two-way volume equation for estimating the apparent culm volume of one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. The volume equation was derived from the assumptions that (1) the relative culm form can be expressed by Kunze’s
equation and (2) normal form-factors at two different relative heights are steady at constants independent of culm sizes.
A total number of 200 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan, and were randomly bisected into two sets of data, i.e. modeling and test
data. For the modeling data, normal form-factors at 0.6 and 0.9 in relative height were steady at 0.908 and 0.448, respectively.
The coefficients of the volume equation were determined based on these steady values of the normal form-factors. For the test
data, the apparent culm volume was estimated from diameter at breast height and culm height with the determined volume equation.
The mean error and root mean square error of the estimated culm volume were, respectively, 8.120 × 10−5 and 3.291 × 10−3 m3, and there was no significant difference between estimated and actual volume. In conclusion, the two-way volume equation
presented here appears to be convenient for predicting the apparent culm volume for P. pubescens. 相似文献
110.
A fraction containing low-molecular-weight peptides that catalyzes redox reactions between electron donors and O2 to produce ·OH, was partially purified from wood-decaying cultures of the brown-rot fungusTyromyces palustris. Polyclonal antibodies raised to the fraction were used for immunogold labeling of transverse sections of sapwood of spruce in various stages of degradation byT. palustris to demonstrate the cellular localization of the ·OH-producing substance. Initially, the wood cell wall was attacked primarily by fungal hyphae growing in the cell lumen. During the early stages of degradation, the gold label was localized in the fungal cytoplasm and cell wall and in the extracellular slime sheath surrounding the fungal cell wall. The gold label also was found throughout the wood cell wall, although the cell wall remained almost intact so long as the fungal hyphae remained in the lumen. Thus, the ·OH-producing substance is secreted by the hyphae into the lumen, and it diffuses through the S3 layer into the S2 layer and the middle lamella. The role of this ·OH-producing system in wood degradation byT. palustris is discussed. 相似文献