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41.
Towada Ando soils consisted of five soils—Towada-a (1,000 years old), Towada-b (2,000 years old), Chuseri (4,000 years old), Nanbu (8,600 years old), and Ninokura soils (10,000 years Amorphous clay materials of these soils taken at different localities were studied by the combined use of selective dissolution and differential infrared spectroscopy, X-ray analysis, electron microscopy, etc. The main clay minerals of Towada-a soils, present-day soils, were montmorillonite-vermic-ulite chloritic intergrades and opaline silica, or these minerals and allophane in the humus horizons, and allophane in the non-humus ones. Towada-b soils overlain by the Towada-a soils showed the clay mineralogical constituents similar to those of Towada-a soils. However, allophane was one of the main clay minerals in all the humus horizons as well as non-humus ones. The main clay minerals of Chuseri soils were allophane and layer silicates consisting chiefly of chloritic intergrades and chlorite in the humus horizons, and allophane in the non-humus ones. Opaline silica was present in minor amounts in the humus horizons of Chuseri soils, but nearly absent in Nanbu and Ninokura soils. There were remarkable differences in the clay mineralogical composition of Nanbu and Ninokura soils with differences of their environmental conditions. Allophane and imogolite Were dominant in the clay fractions of both humus and non-humus horizons of very shallowly buried Nanbu soil which was subjected to the strong leaching process. Allophane was the main clay mineral of deeply buried Nanbu and Ninokura soils which showed the absence of notable accumulation of bases and silica. On the contrary, halloysite with a small amount of siliceous amorphous material appeared in very deeply buried Nanbu and Ninokura soils where bases and silica were distinctly accumulated. The amounts of halloysite in the clay fractions were larger in the humus horizons than non-humus ones, and in Ninokura soil than Nanbu soil. Soil age, soil organic matter, and depositional overburden of tephras were observed to be conspicuous among various factors relating to the weathering of amorphous clay materials in Towada Ando soils. 相似文献
42.
The authors described a novel submerged batch culture system that produced high levels of amylase by Aspergillus kawachii using whole barley (WB), the surface of which is covered by its husk. In this study, detailed analyses determining the amylase activities, residual sugars, fungal morphology and expression levels of genes were performed in a submerged culture using WB to address the mechanism underlying high amylase productivity in A. kawachii. High levels of glucoamylase and acid-stable u-amylase were produced in this culture, and expression levels of amylases, as well as glucose-repressive genes including high-affinity glucose transporter and peroxidase/catalase were also high. On the other hand, the morphology of mycelia was altered, with swollen, bulbous, multi-septum hyphae and conidiophores that normally form in a solid culture being partially generated. Furthermore, cell cycle and post-translational modification-related gene expression levels were altered, and were similar to those in the solid culture. These findings suggest that high amylase productivity in the submerged culture using WB is accompanied by both the up-regulation of amylase genes and activation of post-translational modifications due to fungal morphological changes being brought closer to those in the solid culture. 相似文献
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Naoto Fukazawa Ryota Takahashi Hinako Matsuda Yuya Mikawa Toshiyuki Suzuki Tomohiro Suzuki Shoji Sonoda 《Journal of Pesticide Science》2021,46(4):360
RNA-seq data analysis of cigarette beetle (Lasioderma serricorne) strains having different sensitivities to pyrethroids identified sodium channel mutations in strains showing pyrethroid resistance: the T929I and F1534S mutations. These results suggest that reduced sensitivity of the sodium channel confers the pyrethroid resistance of L. serricorne. Results also showed that the F1534S mutation mostly occurred concurrently with the T929I mutation. The functional relation between both mutations for pyrethroid resistance is discussed. 相似文献
45.
Hisao IWAMOTO Takafumi GOTOH Shoji TABATA Shotaro NISHIMURA Satoru OKAMOTO 《Animal Science Journal》2003,74(2):111-118
The histochemical profiles of myofibers in Musculus pectoralis (PT) and M. supracoracoideus (SC) fasciculi were compared among Japanese quail strains with large, normal and small body sizes. In male and female adults, both the PT and SC muscles had attained a 2.5–2.7-fold weight gain in the large strain and conversely a 0.43–0.50-fold change in the small strain relative to those of the normal size. The muscles were composed of fasciculi with a central cluster of type IIA fibers surrounded by a peripheral layer of type IIB fibers. In the large strain, the cross sectional area (CSA) of the fasciculus and CSA of the fibers in each type were significantly enlarged compared with those in the normal size, with the exception of the fasciculus in the deep region of the male PT muscle. The hypertrophied type IIA fibers in the large strain showed considerable variation in nicotinamide adenine dinucleotide dehydrogenase activity, some of which might represent a transitional form into type IIB fibers. In the small strain, the fasciculus CSA did not significantly differ from that of the normal size except for the PT surface region of the male. However, fiber atrophy was observed in type IIB fibers of the PT surface region in both sexes, and type IIA fibers of the PT deep region and SC muscle in the small strain male quails. The relative fiber type composition of a fasciculus in each region showed only a slight change across the strains. These results indicate that breast muscle hypertrophy in the large strain could be based mainly on fasciculus and fiber hypertrophy, but muscle atrophy in the small strain is not induced by fasciculus and fiber atrophy. 相似文献
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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
48.
Expression of nitric oxide synthase-3 in porcine oocytes obtained at different follicular development 总被引:2,自引:0,他引:2
Takesue K Tabata S Sato F Hattori MA 《The Journal of reproduction and development》2003,49(2):135-140
The present study was designed to determine the localization of nitric oxide synthase-3 (NOS-3) in porcine follicles during follicular development. A 130-kDa NOS-3 protein was found with greater frequency much in the oocytes than in the cumulus cells, as revealed by Western blotting analysis. The content of NOS-3 in the oocyte was higher in large follicles (> 7-mm diameter) than in small follicles (< 2-mm). The data by Western blotting showed the same pattern as the observations obtained from the immunohistochemical studies, in which the periphery of the oocyte stained strong positive. The inner surface cell layer of granulosa cells and cumulus cells were positive staining, especially in large antral follicles. In the primordial follicles, NOS-3 was restricted to the cytoplasm of oocytes, and no stained product was observed in the nucleus of oocytes or granulosa cells. A significant synthesis of NO by oocytes was observed in the presence of ionomycin, but not in the absence of ionomycin, indicating that oocyte NOS-3 functions in response to transient elevations in the intracellular calcium level. We concluded that NOS-3 is expressed in the oocyte from the primordial follicular stage to antral follicular stage, and that it is functional at least in the antral follicles. 相似文献
49.
50.
Mariko Shoji Hidenori Sato Remi Nakagawa Ryo Funada Takafumi Kubo Shinjiro Ogita 《Journal of Forest Research》2006,11(6):449-453
The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of
Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though
somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development
of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000
in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of
embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production
of good quality somatic embryos in P. densiflora. 相似文献