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901.
The contents of fat, starch, pentosan, fructan, β-glucan and several mono- and oligosaccharides in grain were evaluated to find out the possible effects of the Wx-D1 gene of bread wheat using two sets of near-isogenic waxy and non-waxy lines and two low-amylose mutant lines with a common genetic background of Kanto 107. These materials have two non-functional Wx-A1b and Wx-B1b alleles in common. Waxy near-isogenic lines with a non-functional Wx-D1d allele showed consistently increased contents of fat, total fructan, β-glucan, glucose, fructose, sucrose, 1-kestose, 6-kestose, neokestose, nystose and bifurcose compared with non-waxy lines with a functional Wx-D1a allele throughout three growing/harvest seasons. Starch and total pentosan contents were inconsistently influenced by the allelic status of the Wx-D1 locus, while water-soluble pentosan and raffinose contents were not affected. The compositional changes of a low-amylose mutant line with an almost non-functional Wx-D1f allele were closely similar to those of waxy near-isogenic lines, while significantly different changes were barely observed in another low-amylose mutant line with a partly functional Wx-D1g allele in two seasons. These results showed that the Wx-D1 gene has pleiotropic effects on the fat and saccharide contents of bread wheat grain. 相似文献
902.
A spectrophotometric assay based on the color reaction between didecyldimethylammonium chloride (DDAC) and 4-[4-(dipropylamino)phenylazo]-benzenesulfonic acid (propyl orange) was used for the determination of DDAC as a wood preservative. The assay was carried out using a propyl orange solution at pH 2.9. The visible absorbance spectrum of propyl orange showed an absorbance maximum at 510 nm, which decreased continuously with increasing DDAC concentration from 0 to 20 ppm. A linear correlation was observed at a DDAC concentration lower than 8 ppm. To apply this assay method to determine DDAC retention in treated wood, the influence of wood extractives on the assay was investigated. Wood extractives from sapwood and heartwood of Japanese cedar, Hinoki cypress, Japanese larch, and Western hemlock showed no influence on DDAC determination except in the case of heartwood from Japanese cedar and Hinoki cypress, which gave apparent DDAC concentrations higher than the actual values. However, it was also found that absorbance measurement at 477 nm solved this overestimation and gave precise values. It was concluded that this assay is a viable alternative to the current methods for DDAC determination. 相似文献
903.
Jun YAMASHITA Hironori OKI Telhisa HASEGAWA Takeshi HONDA Tetsuro NOMURA 《Journal of Equine Science》2010,21(2):11-16
To investigate the breeding structure in the Japanese Thoroughbred population, we applied
a demographic analysis to the populations of foals produced from 1978 to 2005. The
migration rate estimated from the proportion of foals produced by imported breeding horses
was around 40% over the investigated period. After early 1990s, the migration rate through
stallions imported from USA sharply increased. The average generation interval was within
range of 10.5–11.5 years. The longer generation interval of Thoroughbred was considered to
be a reflection of the fact that Thoroughbred horses begin breeding only after completing
their performance in races. After the peak of 729 in 1993, the number of sires of foals
progressively declined to 358 in 2005. Although the coefficient of variation of the
progeny number of sires was within range of 1.0–1.2 until early 1990s, it gradually
increased and reached the value of 1.6–1.7 in recent years. The effective number of sires
consistently decreased after the peak of 302.6 in 1992, and reached 120–130 in recent
years, which is 25–30% of the actual number of sires. In parallel, the demographic
estimate of the effective population size declined after early 1990s. The main cause of
the observed change in the breeding structure was inferred to be the intensive use of a
limited number of stallions for breeding. 相似文献
904.
Kensaku Maejima Hideo Hoshi Masayoshi Hashimoto Misako Himeno Takeshi Kawanishi Ken Komatsu Yasuyuki Yamaji Hiroshi Hamamoto Shigetou Namba 《Journal of General Plant Pathology》2010,76(3):229-231
For the first time, plum pox virus (PPV) has been detected in commercial Japanese apricot (Prunus mume) trees in Tokyo, Japan. These trees had ringspot or mottle on leaves, color breaking of petals and, occasionally, mild ringspots
and malformation on fruits. The virus was identified based on the morphology of virus particles, serology, and RT-PCR. The
amplified nucleotide fragment shared 100% identity with a partial coat protein gene of PPV-D isolates. 相似文献
905.
Satoshi Kagiwada Yusuke Kayano Hideo Hoshi Takeshi Kawanishi Kenro Oshima Hiroshi Hamamoto Hiromichi Horie Shigetou Namba 《Journal of General Plant Pathology》2010,76(5):345-347
In summer 2007, leaf and stem rot of ice plants was found in a hydroponic greenhouse in Japan. The causal agent was a fungus
identified as Choanephora cucurbitarum (Berkeley & Ravenel) Thaxter, based on pathogenicity, morphology, mating tests, and sequence analysis of the ribosomal DNA
ITS region. 相似文献
906.
Hideyuki Mannen Riku Yonesaka Aoi Noda Takeshi Shimogiri Ichiro Oshima Kiyomi Katahira Misao Kanemaki Tetsuo Kunieda Yousuke Inayoshi Fumio Mukai Shinji Sasazaki 《Animal Science Journal》2017,88(5):739-744
This study aims to estimate the mitochondrial genetic diversity and structure of Japanese Polled and Kuchinoshima feral cattle, which are maintained in small populations. We determined the mitochondrial DMA (mtDNA) displacement loop (D‐loop) sequences for both cattle populations and analyzed these in conjunction with previously published data from Northeast Asian cattle populations. Our findings showed that Japanese native cattle have a predominant, Asian‐specific mtDNA haplogroup T4 with high frequencies (0.43–0.81). This excluded Kuchinoshima cattle (32 animals), which had only one mtDNA haplotype belonging to the haplogroup T3. Japanese Polled showed relatively lower mtDNA diversity in the average sequence divergence (0.0020) than other Wagyu breeds (0.0036–0.0047). Japanese Polled have been maintained in a limited area of Yamaguchi, and the population size is now less than 200. Therefore, low mtDNA diversity in the Japanese Polled could be explained by the decreasing population size in the last three decades. We found low mtDNA diversity in both Japanese Polled and Kuchinoshima cattle. The genetic information obtained in this study will be useful for maintaining these populations and for understanding the origin of Japanese native cattle. 相似文献
907.
Pamela Gan Nanako Nakata Takeshi Suzuki Ken Shirasu 《Journal of General Plant Pathology》2017,83(1):14-22
Colletotrichum fungi belonging to the Colletotrichum gloeosporioides species complex include a number of economically important postharvest pathogens that often cause anthracnose. Until now, different species within this group could only be distinguished from one another reliably using multigenic phylogenetic analyses. Using a comparative genomics approach, we developed a marker that can differentiate Colletotrichum fructicola, Colletotrichum aenigma and Colletotrichum siamense within the C. gloeosporioides species complex based on PCR amplicon size differences. When we used this marker to classify 115 isolates collected over 20 years from strawberries in Chiba Prefecture, Japan, the isolates were predominantly C. fructicola. To our knowledge, this is the first report characterizing different species of Colletotrichum infecting strawberries in Japan and contributes to our understanding on the diversity of anthracnose pathogens in Japan. 相似文献
908.
Tomoo?MisawaEmail authorView authors OrcID profile Miyuki?Kayamori Daisuke?Kurose Jun?Sasaki Takeshi?Toda 《Journal of General Plant Pathology》2017,83(6):406-409
Blight on leaves, stems and bulbs of lilies grown in a greenhouse were found in Hokkaido, Japan, in 2012. Two isolates obtained from the lesions were identified as Rhizoctonia solani anastomosis group (AG)-11 based on morphology and molecular analysis. Original symptoms were reproduced after artificial inoculation with the isolates. Except for R. solani AG-2-1 and AG-4 HG-I, none of the AGs have been reported as pathogens causing lily Rhizoctonia disease in Japan; therefore, we propose adding AG-11 as a pathogen of the disease. More importantly, we report the first appearance of crop disease caused by AG-11 in Japan. 相似文献
909.
910.
Wei-hua Song Zhen-lin Liang Rong Wan Fen-Fang Zhao Kinoshita Takeshi Liu-yi Huang Jia-zhi Ma Bo-hai Chen 《Fisheries Science》2012,78(3):491-501
The effect of horizontal waves on flexible netting panels placed at angles to the wave direction is studied with the aim of evaluating the testing method of pre-tensioned mooring and radial systems and flexible netting structures. The netting was hung on a frame at a specific hanging ratio for ten types of polyethylene panels. Regular waves were experimentally generated with a wave period varying from 0.8 to 2.0 s and wave height ranging from 50 to 250 mm. The force on the netting structure was recorded by a tension transducer and a digital signal recorder. The results showed that the horizontal wave force on the netting panel changed periodically and asymmetrically when it was back and left or right declinate to the wave direction; similar results were found for the surface wave elevation. The opposite results were obtained when the sloping angle declinated front to the wave direction, with two obvious crests during each period. The horizontal wave force was related to the height and width of the netting panel, wave height, wave length, twine diameter, bar length of the mesh, and sloping angle relative to the wave direction. Using dual series relations, the least square approximation, and multiple stepwise regression analysis, the formula for estimating the maximum value of the wave force on the netting was obtained. 相似文献