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471.
Haruki Nakajima Atsushi Kume Megumi Ishida Tohru Ohmiya Nobuya Mizoue 《Annals of Forest Science》2011,68(8):1333-1340
• Context
In long-term forest monitoring, tree crown condition has been visually rated to diagnose tree vigor and forest condition. However, visual estimates are subjective. A semiautomatic image analysis system, called CROCO, was developed to estimate crown condition quantitatively. CROCO calculates a DSO value which decrease with increasing crown transparency. 相似文献472.
Yoshio MINAMI Minako KAWAI Taiko C. MIGITA Atsushi HIRAGA Hirofumi MIYATA 《Journal of Equine Science》2011,22(2):21-28
Although high oxygen consumption in skeletal muscle may result in severe oxidative
stress, there are no direct studies that have documented free radical production in horse
muscles after intensive exercise. To find a new parameter indicating the muscle adaptation
state for the training of Thoroughbred horses, we examined free radical formation in the
muscle by using electron paramagnetic resonance (EPR). Ten male Thoroughbred horses
received conventional training for 18 weeks. Before and after the training period, all
horses performed an exhaustive incremental load exercise on a 6% incline treadmill. Muscle
samples of the middle gluteal muscle were taken pre-exercise and 1 min, 1 hr, and 1 day
after exercise. Muscle fiber type composition was also determined in the pre-exercise
samples by immunohistochemical staining with monoclonal antibody to myosin heavy chain. We
measured the free radical in the muscle homogenate using EPR at room temperature, and the
amount was expressed as relative EPR signal intensity. There was a significant increase in
Type IIA muscle fiber composition and a decrease in Type IIX fiber composition after the
training period. Before the training period, the mean value of the relative EPR signal
intensity showed a significant increase over the pre-exercise value at 1 min after the
exercise and an incomplete recovery at 24 hr after the exercise. While no significant
changes were found in the relative EPR signal intensity after the training period. There
was a significant relationship between percentages of Type IIA fiber and change rates in
EPR signal intensity at 1 min after exercise. The measurement of free radicals may be
useful for determining the muscle adaptation state in the training of Thoroughbred
horses. 相似文献
473.
WANG Chun-ming Hideshi Yasui Atsushi Yoshimura SU Chang-chao ZHAI Hu-qu WAN Jian-min 《中国农业科学(英文版)》2003,2(1)
Grh2, a green rice leafhopper resistant gene from an indica cultivar DV85, was located onchromosome 11, and two RFLP markers C189 and G1465 were found to be linked to this gene. In order totransfer Grh2 into Taichung65, a japonica cultivar with elite characters, backcross method with Taichung65as the recurrent parent was used and the two RFLP markers were converted into CAPS markers for marker as-sisted selection (MAS). In the BC6F3 population, both phenotypic evaluation and MAS were conducted toscreen the resistant plants with Taichung65 background. The linkage distance between CAPS markers andGrh2 was calculated and the efficiency of MAS was analyzed. 相似文献
474.
Maejima Y Aoyama M Ookawara S Hirao A Sugita S 《Veterinary journal (London, England : 1997)》2009,181(2):193-199
Previously it has been shown that androgen suppresses transportation-induced increases in plasma adrenocorticotropic hormone (ACTH), possibly by suppressing the secretion of corticotrophin releasing hormone (CRH) or arginine vasopressin (AVP) from the hypothalamus, or secretion of ACTH from the pituitary gland. The aim of the present study was to examine androgen target sites in the caprine diencephalon and pituitary gland using immunohistochemical methods. The androgen receptor (AR) was expressed strongly in the bed nucleus of the stria terminalis, the medial preoptic area, the arcuate nucleus, the ventromedial hypothalamic nucleus and the suprachiasmatic nucleus in the diencephalon. Between 8% and 11% of CRH and AVP neurons in the paraventricular hypothalamic nucleus (PVN) expressed AR. In the pituitary gland, 7.1% of corticotrophs expressed AR. The results are consistent with the proposal that androgen acts directly and indirectly on CRH and/or AVP neurons in the PVN. The possibility of a direct action of androgen on the corticotrophs in the pituitary gland was also considered. 相似文献
475.
Yabuzoe A Shimizu A Nishifuji K Momoi Y Ishiko A Iwasaki T 《Veterinary immunology and immunopathology》2009,127(1-2):57-64
The target antigen of autoantibodies in human pemphigus foliaceus (PF) is a desmosomal cadherin, desmoglein 1 (Dsg1). It was demonstrated by immunoelectron microscopy (IEM) that the location of the binding sites of PF autoantibodies in the human epidermis was the extracellular regions of the desmosomes. Only a limited number of canine PF sera were shown to react with canine Dsg1, and the target proteins have not yet been identified. The purpose of this study was to demonstrate the ultrastructural binding site of canine PF autoantibodies to the canine skin by two kinds of IEM methods. Three canine PF sera, which were shown to react with the keratinocyte cell surface by immunofluorescence, were tested in this study. Using a technique of immunoprecipitation-immunoblotting, one out of the three canine PF sera were shown to react with recombinant canine Dsg1. By post-embedding IEM using cryofixation technique, one serum, which did not react with canine Dsg1 by immunoprecipitation-immunoblotting, bound broadly to the extra- and intracellular regions of the desmosomes of normal canine skin. By pre-embedding IEM using canine cultured keratinocytes (MCA-B1 cells), the autoantibodies of all three canine PF sera were identified to be bound to the cell-cell contact area of the adjacent cytoplasmic projections. When double stained with human PF serum and canine PF sera, the binding sites of both human and canine autoantibodies were co-localized on the MCA-B1 cells where the cytoplasmic projections contacted each other. Therefore, it may be concluded that the serum antibodies of canine PF targeted desmosomal proteins, regardless of whether or not they react with canine Dsg1 by immunoprecipitation-immunoblotting method. 相似文献
476.
Satoshi Yamada Atsushi Takeoka Masuo Yamanouchi 《Soil Science and Plant Nutrition》2013,59(4):969-974
Detached leaves of several crop plants were cultured in a nutrient solution containing 32P, and the 32P mobility between and within organs was investigated. The results obtained were as follows: 1) In soybean and adzuki bean, 32P was well distributed all over the leaf blade and petiole within 24 h after 32P absorption, though the transfer of 32P from the leaf vein to the mesophyll varied among the varieties. 2) In rice, 32P reached the middle or proximal part of the leaf blade within 48 h after 32P absorption. The gradient of 32P density decreased distally. 3) In maize and pumpkin, a small amount of 32P reached the leaf blade; in maize, the gradient of 32P density was similar to that in rice, though 32P was retained in the whole petiole in pumpkin. Besides transpiration, 32P transfer from xylem to mesophyll and structures of leaf tissues could be considered to regulate the 32P mobility. 相似文献
477.
Junta Yanai Taichi Omoto Atsushi Nakao Kana Koyama Arief Hartono Syaiful Anwar 《Soil Science and Plant Nutrition》2013,59(2):188-195
AbstractTo evaluate the content of nitrogen (N) fractions of agricultural soils in Java, Indonesia, in relation to soil type and land use, 46 surface soil samples, 23 from paddy and 23 from upland, were collected throughout Java to include various types of soils. Soil N was separated into four fractions according to form and availability: inorganic extractable nitrogen (Iex-N), fixed ammonium nitrogen (Ifix-N), organic mineralizable nitrogen (Omin-N) and organic stable nitrogen (Osta-N). The total-N content was determined by the dry combustion method. The Iex-N content was determined by extraction with a 2 mol L?1 potassium chloride (KCl) solution and the Ifix-N content by extraction with an hydrofluoric and hydrochloric acid (HF-HCl) solution after removal of organic-N. The Omin-N content was evaluated as the potentially mineralizable N based on a long-term incubation method. The Osta-N content was calculated as the difference between the contents of total-N and the three other fractions. The total-N content was 2.06 g kg?1 on average. The contents of Iex-N, Ifix-N, Omin-N and Osta-N were 25.8, 99.1, 103 and 1,832 mg kg?1, respectively, and corresponded to 1.3, 4.8, 5.0 and 88.9% of the total-N. Hence, available (Iex-N and Omin-N) and stable (Ifix-N and Osta-N) fractions accounted for 6.3% and 93.7% of the total-N, respectively. Correlation analysis indicated that the contents of total-N and Osta-N had positive correlation with (Alo + 1/2Feo) as an index of amorphous minerals (p < 0.01), suggesting strong influence of volcanic materials for the accumulation of organic matter in Java soils. The content of Ifix-N had a positive correlation with nonexchangeable potassium (K) content (p < 0.01), suggesting the contribution of 2:1 clay minerals which can fix both ammonium (NH4+) and K+ in their interlayer sites. On the contrary, Omin-N did not have any significant correlation with soil properties, implying the importance of management for the improvement of the available N level in soils, rather than intrinsic soil properties. Soil N status further showed strong topographical trends depending on the elevation where soil developed. The contents of total N, Iex-N, Ifix-N, Omin-N and Osta-N in Java soils were on average 80, 69, 90, 65 and 80% of those in Japanese soils, respectively, suggesting that the soil N level in Java was lower than that in Japan, probably due to accelerated decomposition of organic matter, especially degradable fractions, reflecting high temperature, but that the level was relatively high for tropical soils due to the effect of volcanic materials. In conclusion, these results should be taken into account for the sustainable management of soil N in agricultural fields in Java, Indonesia. 相似文献
478.
Hiromi Nakanishi Houdo Tanaka Kouki Takeda Keitaro Tanoi Atsushi Hirose Seiji Nagasaka 《Soil Science and Plant Nutrition》2013,59(6):801-808
AbstractRadioactivity levels of cesium (Cs)-134 and 137Cs in bamboo [Phyllostachys reticulata (Rupr) K. Koch] sprouts grown from April to June 2011 over a wide area (including Fukushima Prefecture) were elevated (max. 3100 Bq kg?1 fresh weight) after the Tokyo Electric Power Company, Inc. (TEPCO) Fukushima Daiichi Nuclear Power Plant disaster in March 2011. Bamboo sprouts in 2012 also contained high radioactivity levels. Radioactivity imaging analysis of bamboo sprouts harvested in 2012 showed increasing concentration gradients of radioactivity from the lower parts to the top of the sprouts. The peels were individually separated from the sprouts, and the inner edible part (trunk) was cross-sectioned at the internodal sections from the top to the lower parts. Each segmented trunk and its corresponding peel were analyzed for radioactive cesium (134Cs and 137Cs) and stable cesium (133Cs). The concentrations of 134Cs and 137Cs showed significant increases from the lower part to the top, whereas 133Cs showed an almost constant value in the trunk and peel except in the peel of the top node. We speculated that 134Cs and 137Cs in newly emerging bamboo sprouts in 2012 were translocated mainly from various plant tissues (where the fallout was layered on the bamboo tissues) in older bamboo, while 133Cs was translocated from the soil through the roots of the new bamboo sprouts and was present in the roots and stems. 相似文献
479.
480.
Einstine Opiso Atsushi Asai Tsutomu Sato Tetsuro Yoneda Xiaoji Liu 《Water, air, and soil pollution》2012,223(6):3471-3483
The utilization and disposal of alkaline waste materials such as slag and coal fly ash as cement aggregates and raw materials in cement manufacturing can pose environmental and health hazards because these waste materials usually contain elevated concentration of toxic elements. This study examined the possibility of controlling the pore water chemistry of these waste materials in order to induce the secondary mineral formation of Mg-bearing minerals as major sorbing solids for oxyanions during the utilization and disposal of alkaline wastes. The formation of Mg-bearing minerals was examined at ambient temperature and alkaline pH conditions in the Mg?CSi?CAl system. The interaction of Mg-bearing minerals with oxyanions using arsenate as an analog was examined during and after mineral formation. The results revealed that the generated Mg-bearing mineral phases were smectite and brucite in Mg?CSi system and hydrotalcite and serpentine in Mg?CSi?CAl system. Moreover, hydrotalcite, serpentine, brucite, and smectite phases formed under low Si ratio showed high sorption capacity for arsenate, but only high Al content hydrotalcite and serpentine showed substantial irreversible fraction of sorbed arsenate. Hence, the generation of these kinds of hydrotalcite and serpentine phases as scavengers for oxyanions must be considered during the utilization and disposal of alkaline wastes. 相似文献