全文获取类型
收费全文 | 1060篇 |
免费 | 58篇 |
国内免费 | 4篇 |
专业分类
林业 | 81篇 |
农学 | 54篇 |
151篇 | |
综合类 | 56篇 |
农作物 | 52篇 |
水产渔业 | 113篇 |
畜牧兽医 | 535篇 |
园艺 | 12篇 |
植物保护 | 68篇 |
出版年
2023年 | 3篇 |
2022年 | 10篇 |
2021年 | 35篇 |
2020年 | 17篇 |
2019年 | 18篇 |
2018年 | 32篇 |
2017年 | 23篇 |
2016年 | 36篇 |
2015年 | 37篇 |
2014年 | 28篇 |
2013年 | 74篇 |
2012年 | 42篇 |
2011年 | 67篇 |
2010年 | 30篇 |
2009年 | 31篇 |
2008年 | 69篇 |
2007年 | 66篇 |
2006年 | 56篇 |
2005年 | 88篇 |
2004年 | 51篇 |
2003年 | 58篇 |
2002年 | 39篇 |
2001年 | 36篇 |
2000年 | 33篇 |
1999年 | 24篇 |
1998年 | 13篇 |
1997年 | 3篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 10篇 |
1985年 | 10篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1971年 | 1篇 |
1970年 | 7篇 |
1969年 | 2篇 |
1967年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1122条查询结果,搜索用时 31 毫秒
71.
Treatment by Sivanesan and Gibson (1976), that combined all species of Entomosporium into one species E. mespili (DC. ex Duby) Sacc, was supported through the investigation of many exsiccati and fresh specimens.Morphologically, all specimens and isolates of Entomosporium, which had been differentiated into 4 species, could not be divided into clearly separated groups.The fungus has been recorded on 50 host species and the disease is widespread throughout the world. 相似文献
72.
Masaki Harada Youko Hayashi Tomoyuki Hayashi Masahiko Karube Toshimasa Ohgama 《Journal of Wood Science》2005,51(3):282-285
To investigate the effect of moisture content (MC) of members on the mechanical properties of timber joints, bending tests of precut joints and shear tests of dowel-type joints were carried out using timbers of Japanese cedar (Cryptomeria japonica D. Don) with three moisture conditions: green, kiln-dried with a MC target of 15%, and over-kiln-dried with a MC target of 5%. For the bending test, timbers were processed with a precut processing machine into “koshikake-ari” (a kind of dovetail joint) and “koshikake-kama” (a kind of mortise and tenon joint). A pair of members was jointed together without mechanical fasteners. Bolts (diameter = 12 mm) and nails (diameter = 2.45 mm) were used as dowels in the shear test. Bolted joints were constructed with one bolt and two metal side plates. Two nails and two metal side plates were used for the nailed joint. For precut joints, no clear effect of MC was recognized on maximum moment and initial stiffness. The maximum strength of mechanical joints assembled with kiln-dried wood was changed by the degree of drying. Stiffness of the joints assembled with kiln-dried specimens was larger than that of the joints assembled with green specimens.Part of this study was presented at the 7th International IUFRO Wood Drying Conference, Tsukuba, July 2001 相似文献
73.
Yi Min Wei Bunichiro Tomita Yasushi Hiramatsu Atsushi Miyatake Tsuyoshi Fujii Tomoyuki Fujii Shuichiro Yoshinaga 《Journal of Wood Science》2003,49(4):317-326
Poor compatibility was found between exploded wood fiber strand (WFS) and cement due to the excessive presence of water-soluble degraded polysaccharides in extractives of exploded WFS obtained from weathered wood waste treated by the water-vapor explosion process (WVEP). This study presents some comparative results from a continuing investigation on the compressive strengths of exploded WFS–cement mixtures. Based on results previously obtained with the hydration test, the relation between hydration behavior and compressive strength of the mixture was explored. In addition, the effect of the curing age on compressive strength development of the mixture with selected additive chemicals was examined. The results supported the results of early studies with hydration tests indicating that adding MgCl2 to the mixtures of exploded WFS mixed with quick-curing cement or ordinary Portland cement and a composite of MgCl2 + CaO added to the mixture of exploded WFS and furnace-slag cement effectively improved the hydration behaviors; it greatly enhanced the compressive strengths of mixtures as well. Compressive strengths were strongly correlated to maximum hydration temperatures (Tmax) of wood–cement mixtures influenced by the cement type, wood wastes (treated or not with WVEP), additive chemicals, and their content levels. The results also indicated that adding selected chemicals had no significant effect on compressive strength among the mixtures of exploded WFS mixed, respectively, with three types of cement at a curing age of 180 days. X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy were used to identify the hydration products and to probe the element distribution of the mixture in the wood–cement interface zone from a fractured surface.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002 相似文献
74.
Hiroshi ISEKI Michihiro TAKAGI Kenji KAWASHIMA Tomoyuki SHIBAHARA Yoshiko KURODA Hiroshi TSUNEMITSU Makoto YAMAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1663-1666
To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory
syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical
signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned
and reddish in appearance; had lesions predominantly in the cranial, middle and accessory
lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were
reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions,
no significant differences were noted between the challenge and control groups regarding
mean rectal temperature and daily weight gain. These results provide useful insights into
the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in
piglets, which differ from findings in reported field cases. 相似文献
75.
Effects of utilization of local food by‐products as total mixed ration silage materials on fermentation quality and intake,digestibility, rumen condition and nitrogen availability in sheep
下载免费PDF全文
![点击此处可从《Animal Science Journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Srita Yani Kyohei Ishida Shuzo Goda Shigeyoshi Azumai Tomoyuki Murakami Masayuki Kitagawa Kanji Okano Kazato Oishi Hiroyuki Hirooka Hajime Kumagai 《Animal Science Journal》2015,86(2):174-180
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by‐products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by‐products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) were obtained. Four types of TMR silage were used: control (C) containing roughage and commercial concentrate, T1:20% and T1:40% containing the five by‐products replacing 20% and 40% of the commercial concentrate on a dry matter (DM) basis, respectively, and T2:40% containing three by‐products (potato waste, noodle waste and soybean curd residue) replacing 40% of the commercial concentrate on a DM basis. The ingredients were mixed and preserved in oil drum silos for 4 months. The TMR silages showed 4.02–4.44% and 1.75–2.19% for pH and lactic acid contents, respectively. The digestibility of DM and neutral detergent fiber, and total digestible nutrient content were higher (P < 0.05) for T2:40% feeding than for C feeding. Urinary nitrogen excretion tended to be lower (P = 0.07) for T2:40% than for C. The results suggested 40% replacing of commercial concentrate by using the three food by‐products can be most suitable for TMR silage. 相似文献
76.
To investigate the effects of processing Chinese quince fruit on the denaturation of phenolics and their food functions, fruit phenolic extracts were heated together with organic acid for up to 12 h. Chinese quince phenolic (mostly procyanidins) solution subjected to heat treatment changed from almost colorless, pale yellow, to a reddish color. Before heat treatment, the absorption spectra of polymeric procyanidins were observed only around 280 nm; after heat treatment, absorption occurred between 400 and 600 nm, which is related to the reddish color appearance. Thioacidolysis of denatured reddish phenolics showed that (-)-epicatechin subunits decreased during heat treatment and, in contrast, cyanidin increased. In addition, novel substances that could not be degraded by thioacidolysis were formed. Meanwhile, antioxidant activities, assessed by linoleic acid peroxidation, 1,1-diphenyl-2-picrylhydrazyl (DPPH), Folin-Ciocalteu, and FRAP methods, increased during heat treatment. The antiinfluenza viral activity of denatured reddish phenolics was inferior to that of intact fruit phenolics; however, they retained moderate activity. These results indicate that red coloration of fruit products of Chinese quince was mainly due to the spectral (i.e. structural) changes of procyanidins accompanied with formation of cyanidin. Increasing the length of heat treatment increased the antioxidant capacity of phenolics, and the resultant reddish phenolics retained moderate antiinfluenza viral activity. 相似文献
77.
Y. Yoshiura Y.C. Sohn A. Munakata M. Kobayashi K. Aida 《Fish physiology and biochemistry》1999,21(3):201-210
A cDNA encoding the subunit of thyrotropin (TSH) was isolated from a goldfish (Carassius auratus) pituitary gland cDNA library. By comparing the sequence with other teleost TSHs, a signal peptide of 19 amino acids and a mature hormone of 131 amino acids were predicted for goldfish TSH subunits. The resulting putative mature hormone of 131 amino acids had well-conserved cysteine positions and a putative N-linked glycosylation site; homology was 51–67% with TSHs from other teleosts, 38–43% with tetrapod TSHs, but only 27 and 29% with goldfish GTH-I and -II, respectively. We also examined the effects of thyroid hormones (TH) and thiourea (TU, an inhibitor of TH production) treatments on TSH and GTH subunit gene expressions in the goldfish pituitary gland. After thyroxine (T4) treatment, circulating T4 concentration increased and TSH mRNA level decreased. Supressing the amount of circulating T4 and triiodothyronine (T3) by TU treatment increased the TSH mRNA level. Moreover, T4 replacement therapy (simultaneous treatment of both TU and T4) caused a high level of circulating T4 and a low level of circulating T3, and a decrease in the TSH mRNA level. Thus, changing levels of circulating TH exert a negative feedback on the level of TSH subunit mRNA in goldfish in vivo. On the other hand, GTH subunit mRNA levels were not affected by changes in the levels of circulating TH. 相似文献
78.
S. Kobayashi A. HidanoT. Tsutsui T. YamamotoY. Hayama T. NishidaN. Muroga M. KonishiK. Kameyama K. Murakami 《Research in veterinary science》2014
This cross-sectional study evaluated risk factors associated with farm-level bovine leukemia virus (BLV) seropositivity in 563 dairy and 490 beef farms throughout Japan. Twenty randomly selected cattle on each farm were serologically tested, and farm epidemiologiocal information was obtained through face-to-face interviews. Due to the large number of zero-prevalence dairy and beef farms, data analysis was performed using a zero-inflated negative binomial model, which revealed that the common risk factors associated with higher within-farm seroprevalence were past detection of clinical leukemia and presence of blood-sucking insects. Loose housing on dairy farms and direct contact between calves and adult cattle on beef farms were also identified as risk factors. With regard to farm-level presence of BLV, the presence of purchased cattle was found to be a risk factor in both sectors. Sending heifers to a common ranch was identified as an additional risk factor for dairy farms. 相似文献
79.
Minoru Okabe Motoi Yasumura Kenji Kobayashi Kazuhiko Fujita 《Journal of Wood Science》2014,60(1):49-58
Cross-laminated timber (CLT) panels consist of several layers of lumber stacked crosswise and glued together on their faces. Prototype sugi CLT floor panels were manufactured and bending tests were carried out under the different parameters of lumber modulus of elasticity (MOE), number of layers, thickness of lumber and thickness of CLT panels. On the basis of above tests, bending stiffness and moment carrying capacity were predicted by Monte Carlo method. MOE of lumber was measured by using grading machine and tensile strength of lumber was assumed to be 60 % of bending strength based on the obtained bending test. Bending stiffness EI of CLT panels could be estimated by adopting composite theory and equivalent section area. Experimental moment carrying capacity showed 12 % higher value than the calculated moment carrying capacity by average lumber failure method, and also showed 45 % higher value than the calculated moment carrying capacity by minimum lumber failure method due to the reinforcement of the outer layer by the neighboring cross layer. 相似文献
80.
Masaru Matsuda Yoshitaka Nagahama Tohru Kobayashi Chika Matsuda Satoshi Hamaguchi Mitsuru Sakaizumi 《Fish physiology and biochemistry》2003,28(1-4):135-139
Although the sex-determining gene Sry has been identified in mammals, no comparable genes have been found in non-mammalian vertebrates. To clone positionally the sex-determining region of the medaka, Oryzias latipes, we generated a Y congenic strain to highlight the genetic differences between the X and Y chromosomes from inbred strains of medaka. We used recombinant breakpoint analysis and deletion analysis of the Y chromosome of a congenic XY female to restrict the sex-determining region to 250-kb stretch of the Y chromosome. Shotgun sequencing of this region predicted 27 genes. Three of these genes were expressed during sexual differentiation. However, only one gene was Y specific. The full-length cDNA sequence of this gene encodes a putative protein of 267 amino acids, including the highly conserved DM domain. We thus named it DMY. To establish a role for DMY during sexual differentiation, we screened wild medaka populations for naturally occurring DMY mutants. Two XY females with distinct mutations in DMY were found in separate populations. The first heritable mutant – a single insertion in exon 3 and the subsequent truncation of DMY – resulted in all XY female offspring. Similarly, the second XY mutant female showed reduced DMY expression with a high proportion of XY female offspring. Furthermore, during normal development, DMY is expressed only in somatic cells of XY gonads. These findings strongly suggest that the sex-specific DMY is required for normal testicular development and is a prime candidate for the medaka sex-determining gene. 相似文献