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121.
Ueno K Nomura S Muranaka S Mizutani M Takikawa H Sugimoto Y 《Journal of agricultural and food chemistry》2011,59(19):10485-10490
Striga gesnerioides is a root parasitic weed of economic significance to cowpea (Vigna unguiculata) crops in Western Africa. Seeds of the parasite germinate in response to cowpea root exudates. Germination stimulants for the seeds were isolated from the hydroponic culture filtrate of cowpea, and their structures were unambiguously determined as (-)-(3aR,4R,8bR,2'R)-ent-2'-epi-orobanchol and (+)-(3aR,4R,8bR,2'R)-ent-2'-epi-orobanchyl acetate, on the basis of mass, CD, and (1)H NMR spectra; optical rotatory power; and chromatographic behavior on HPLC. The alcohol was first isolated and identified from the cowpea root exudates, and the acetate may be the same compound that had been previously isolated from the exudates and designated as alectrol. Identity of the stimulants produced by cowpea to those produced by red clover (Trifolium pratense) was confirmed. 相似文献
122.
Nimitkeatkai H Shishido M Okawa K Ohara H Ban Y Kita M Moriguchi T Ikeura H Hayata Y Kondo S 《Journal of agricultural and food chemistry》2011,59(12):6423-6429
The effects of the application of the jasmonic acid derivative n-propyl dihydrojasmonate (PDJ) on ethylene biosynthesis, volatile compounds, and endogenous jasmonic acid (JA) and methyl jasmonate (MeJA) were examined in Japanese apricot (Prunus mume Sieb.) infected by a pathogen (Colletotrichum gloeosporioides). The fruit were dipped into 0.4 mM PDJ solution before inoculation with the pathogen and stored at 25 °C for 6 days. The inoculation induced an increase in 1-aminocyclopropane-1-carboxylic acid (ACC), ethylene, JA, and MeJA. In contrast, PDJ application reduced the endogenous JA, MeJA, and ethylene production and expression of the ACC oxidase gene (PmACO1) caused by the pathogen infection. The lesion diameter with C. gloeosporioides decreased upon PDJ application. The alcohol, ester, ketone, and lactone concentrations and alcohol acyltransferase (AAT) activity increased in the pathogen-infected fruit, but were decreased by PDJ application. These results suggest that PDJ application might influence ethylene production through PmACO1 and that aroma volatile emissions affected by pathogen infection can be correlated with the ethylene production, which is mediated by the levels of jasmonates. 相似文献
123.
Naoki Sasaki Satoru Nishii Kazutaka Yamada Hidehumi Huruoka Yasuhiko Tabata 《Journal of Equine Veterinary Science》2013
Our objective in this study was to examine the effect of gelatin hydrogel (GH) sheets containing basic fibroblast growth factor (bFGF) on healing of proximal sesamoid bone transverse fractures in the horse. Ten healthy adult Thoroughbreds were used. The lateral proximal sesamoid bone of the left forelimb and the medial proximal sesamoid bone of the right forelimb were osteotomized, while the horses were under general anesthesia, and subsequently repaired by lag screw fixation using a single 4.5-mm cortical screw. A GH sheet containing 100 μg of bFGF was then sutured to the synovial membrane adjacent to the osteotomized proximal sesamoid bone. In the control group, the fracture was fixed with a lag screw, and the articular capsule was sutured. Fracture healing was assessed by radiographic examination once a week for 16 weeks after the operation. Radiographic examination of bone healing revealed significantly lower demineralization of the fracture line in the GH sheet-treated group than in the control group. The rate of demineralization of the fracture line in the GH sheet-treated group was significantly lower than that in the control group at 2, 4, and 8 weeks after the operation. In this study, we demonstrated that the use of a GH sheet containing bFGF promotes healing of proximal sesamoid bone fracture in the horse. Therefore, it is believed that this treatment strategy would be useful for quick recovery from bone fracture in the horse. 相似文献
124.
Masaharu MURATA Kotaro FUKUSHIMA Tomoka TAKAO Hiroyuki SEKI Satoru TAKEDA Norio WAKE 《The Journal of reproduction and development》2013,59(1):7-13
Oxidative stress has been recognized as an important factor in the pathophysiology of
preeclampsia. It has been reported that the expression of xanthine oxidase (XO) in the
cytotrophoblast and plasma hydrogen peroxide (H2O2) level are
significantly higher in preeclamptics than in control women. The aim of this study was to
clarify the biological influence of reactive oxygen species (ROS) produced by XO on
extravillous trophoblast (EVT) cells. TCL1 cells, a human immortalized EVT cell line, were
incubated with xanthine and XO (X/XO). We then measured the cell number, urate level of
the culture media and the apoptotic cell ratio. Similar experiments were performed with
additional administration of allopurinol, catalase, L-NAME or D-NAME, and with
administration of H2O2 in substitution for X/XO. We assessed the
effects of H2O2 on invasion ability, tube-like formation and protein
expression of HIF1A and ITGAV of TCL1. Finally, the apoptotic cell ratio using primary
cultured trophoblasts was measured following exposure to H2O2. X/XO
decreased the relative cell number and increased the urate level and apoptotic cell ratio
significantly. Elevation of the urate level and apoptotic cell ratio was attenuated by
allopurinol and catalase, respectively. L-NAME and D-NAME had no influence on these
effects. H2O2 also decreased the relative cell number. Pretreatment
with H2O2 significantly inhibited the invasion ability, tube-like
formation and HIF1A and ITGAV of TCL1. H2O2 also induced apoptosis
in primary cultured trophoblasts. In conclusion, ROS produced by XO induced apoptosis and
affected EVT function including invasion and differentiation. 相似文献
125.
Satoru Kondo Hiroyuki Yoshikawa Rie Katayama 《The Journal of Horticultural Science and Biotechnology》2013,88(3):390-394
SummaryCatechins, ascorbic acid and -cryptoxanthin concentrations during fruit development and the antioxidant activity in skin and flesh were investigated in astringent ‘Saijyo’ and non-astringent ‘Fuyu’ persimmons (Diospyros kaki Thunb.). The IC50 values (a midpoint of 50% between zero and full inhibition of diazo dye formation) of superoxide (O2–)-scavenging activity remained low in the skin throughout fruit development.The IC50 values of the activity increased with d after full bloom (DAFB) in the flesh of the non-astringent type, whereas values remained low until harvest in the astringent type. However, IC50 values increased sharply after the removal of astringency with ethanol spray. Catechin concentrations in the flesh also decreased after the removal of astringency, whereas the concentrations in the skin did not decrease. Ascorbic acid concentrations in the skin and flesh were high at the beginning and middle of fruit development, but -cryptoxanthin in the skin and flesh increased toward harvest. However, -cryptoxanthin concentrations in the skin and flesh were lower than catechins and ascorbic acid. In addition, IC50 in the flesh of the non-astringnet type was high despite the increase of -cryptoxanthin at harvest.These results suggest that catechins and ascorbic acid influence O2-scavenging activity at the beginning and middle of fruit development, and catechins are associated with the O2-scavenging activity at ripening. Changes in 1-diphenyl-2-picrylhydrazyl (DPPH)-radicalscavenging activity with fruit developmental stage were similar to that for O2–. That is, IC50 values of DPPH-radical-scavenging activity decreased rapidly after the removal of astringency. -cryptoxanthin did not eliminate the DPPH-radicals. Therefore, the DPPH-radicals in persimmons may be eliminated primarily by catechins and ascorbic acid. The utilization of tannins before the removal of astringency is discussed. 相似文献
126.
Dendi Muhamad Satoru Okubo Tadashi Miyashita Parikesit Kazuhiko Takeuchi 《Agroforestry Systems》2013,87(6):1247-1260
To halt biodiversity loss in the humid tropics of developing countries, it is crucial to understand the roles and effects of human-modified landscapes with fragmented forest remnants in maintaining biodiversity while fulfilling the demands of local communities and reducing poverty. To implement appropriate landscape planning for conserving biodiversity and ecosystem functioning, appropriate information is required about parameters of habitat suitability among various anthropogenic habitats with a range of distances to forests and vegetation characteristics, but such information is limited. We examined differences in avian communities between a remnant forest and four types of man-made forest (two mature plantations and two agroforests) in a forest–agricultural landscape of West Java, and we analyzed the effects of both local and landscape factors on various types of species richness in this landscape. The results from non-metric multidimensional scaling revealed avifauna in the two types of agroforest was clustered separately from that in the remnant forest, mainly because drastic declines in the abundance of forest specialists (including IUCN red-listed species) and their replacement with open-habitat generalists. The mixed-tree agroforests were colonized by 30 % of forest specialists and forest-edge species found in the remnant forest, and maintained the highest richness of species endemic to Indonesia among man-made forests, implying that some forest specialists and endemics might have adapted to ancient landscape heterogeneity. High proportion of insectivorous birds was found in the remnant forest (more than 50 %) and drastically decline in man-made forests, although the species richness of insectivores did not decline significantly in broad-leaved plantations. We concluded that protection of remnant forests should be prioritized to conserve forest bird diversity. However, as different environmental factors affected the richness values of different ecological groups, appropriate landscape design and habitat management could improve functional diversity in forest–agricultural landscapes in the tropics. 相似文献
127.
Generally, by the stoppage of flood irrigation after the rice growing season, the excess water in paddy field soils is gradually drained off as the ground water level sinks, and soils of plowed layer are generally kept under the oxidised condition due to the introduction of oxygen from the surface of soils during the unirrigated period. 相似文献
128.
Matsuki N Fujiwara K Tamahara S Uchida K Matsunaga S Nakayama H Doi K Ogawa H Ono K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):295-297
To examine the prevalence of autoantibody in canine cerebrospinal fluids (CSFs), CSFs were collected from 14 healthy controls and 88 clinical cases with various diseases in the central nervous system (CNS), and were analyzed by an indirect fluorescence antibody test on frozen sections of the cerebrum from normal Beagle dogs. An anti-astrocyte autoantibody was detected in 31 clinical cases with titers ranging from 1:1 to >/=1:100. All tested cases with necrotizing meningoencephalitis (NME: n=22) and granulomatous meningoencephalitis (GME: n=3) possessed the anti-astrocyte autoantibody, while the autoantibody was negative in most cases with other inflammatory CNS diseases. The autoantibody was also detected in 4 of 12 cases with brain tumors. Hence, examination of the autoantibody in the canine CFS would be significant for diagnosing NME and/or GME, as well as for understanding peritumoral events in cases with brain tumors. 相似文献
129.
Tomohito Arao Satoru Ishikawa Masaharu Murakami Kaoru Abe Yuji Maejima Tomoyuki Makino 《Paddy and Water Environment》2010,8(3):247-257
Many heavy metals exist in minute amounts in natural agricultural soil. However, when their amounts exceed a certain level
due to pollutants brought from outside, soil contamination occurs and agricultural products become contaminated. There have
been many cases in Japan of heavy metal contamination originating from old mines and smelters, and soil contamination of agricultural
land has become a social issue. In particular, cadmium (Cd) is one of the most harmful heavy metals. If agricultural products
absorb an excessive amount of Cd, they may adversely affect people’s health, and therefore allowable concentrations are regulated
by law. If agricultural land has become contaminated with Cd, measures for minimizing the absorption of Cd by agricultural
crops are necessary; these include: (1) soil dressing, (2) water management (paddy field), (3) chemical cleaning of soil,
(4) phytoextraction, and (5) use of different varieties and rootstock. Other heavy metals such as arsenic, lead, copper, zinc,
and mercury also sometimes cause contamination of agricultural soil. 相似文献
130.