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121.
Journal of General Plant Pathology - A BIO-PCR was developed for the detection of potato blackleg pathogens, including Pectobacterium wasabiae (Pw), P. atrosepticum (Pa), P. carotovorum subsp....  相似文献   
122.
We synthesized 33 new phenylpiperazine derivatives and assessed their acaricidal activity. These derivatives were synthesized through sequential reactions consisting of the sulfonylation of 2-substituted 4-methylaniline with chlorosulfonic acid, reduction with red phosphorus and iodine, alkylation by alkyl halide, cyclization with bis(2-chloroethyl)amine hydrochloride, and N-substitution reaction of phenylpiperazines with various reagents. All phenylpiperazines synthesized were evaluated for acaricidal activity and their structure–activity relationships discussed, it was found that 4-substituted 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]piperazine derivatives exhibited good acaricidal activity. Among them, 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]-4-(trifluoromethylsulfonyl) piperazine showed the highest level of activity against Tetranychus urticae and provided a high level of activity against Tetranychus kanzawai and Panonychus citri. In addition, studies on the effect at various stages of T. urticae exhibited that this compound showed good activity against both adults and eggs.  相似文献   
123.
In rural areas of northern Laos, a commercially valuable pioneer tree species, paper mulberry (Broussonetia papyrifera L. Vent.) has been recommended for intercropping under plantations of commercial trees. However, less is understood about the growth of this pioneer tree species in the understorey and the mechanism underlying the shade intolerance. We measured growth characteristics for seedlings of paper mulberry under four light intensities. We compared the relative growth rates in aboveground biomass and standing leaf area (RGRmass and RGRleaf), light-capture efficiency, and seeding-level mass-based daily photosynthetic rates (A mass) with those of field-grown seedlings of eight shade-tolerant species to identify factors potentially responsible for shade-intolerance. Most growth traits of the paper mulberry seedlings did not differ consistently from those of the shade tolerant species. The ecophysiological–architectural model software showed higher A mass and RGRmass capacity in paper mulberry than in shade-tolerant species. Despite their higher RGRmass, paper mulberry seedlings had negative RGRleaf under shaded conditions due to short leaf lifespan. The linear RGRmass–RGRleaf relationship for paper mulberry had a high RGRmass intercept, indicating that a high RGRmass was required to provide positive RGRleaf. Progressive decreases in standing leaf area with time, and possibly photosynthesis, appear to be responsible for the shade-intolerance of paper mulberry. Although intercropping of paper mulberry has been suggested in the species’ native region, understorey cultivation of paper mulberry would only be possible with relatively open canopies.  相似文献   
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Growth hormone receptor (GHR) belongs to a member of the cytokine receptor superfamily. Polymorphism of presence or absence of an approximately 1.2 kbp LINE-1 element is observed in bovine GHR gene. The present study was carried out for estimating the genetic diversity and the origin of the LINE-1 element in 10 European, Southeastern Asian and East Asian cattle breeds or populations. Genotyping of the LINE-1 revealed predominant LINE-1 presence in European breeds (0.917∼0.991), absence in the Bos taurus indicus populations (0.000∼0.017), and intermediate presence in Northeast Asian cattle (0.417∼0.522). From genetic features of LINE families, LINE-1 of GHR could be attributed to the same origin in both European and Asian cattle, and Asian LINE-1 may not be derived from recent introgression. This result suggested that LINE-1 in bovine GHR gene could have arisen in an ancestral population of Bos taurus taurus .  相似文献   
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The objectives of this study were to determine to what extent the flight distance of cows to humans was influenced by sire and management procedures before and after maturity, and whether there was a correlation between the flight distance and productivity on commercial dairy farms. Flight distance of 84 Holstein cows, the stockperson's daily routine management procedures and production performance were recorded repeatedly on eight commercial dairy farms. The management procedures for the animals at the suckling, growing, lactating and dry stages were classified into four categories by degree of tactile interactions between the stockperson and the animal: hand procedures with touch on (category A), nearby (category B) and apart (category C) from the animal, and machinery procedures (category D). There was no apparent sire effect on flight distance ( P  = 0.08), whereas the flight distance ranged from 1.17 ± 0.86 to 4.47 ± 2.01 m by farm ( P  < 0.01), and gradually shortened with repetition ( P  < 0.05). Regression analysis indicated that the length of time of category B at the suckling stage and category B at the dry stage accounted for 37% and 32% of the variation in flight distance, respectively. As for the total time of the four procedure categories, growing stage was the prime predictor of flight distance, which accounted for 36% of the variation. Flight distance tended to correlate with the first calving age ( r  = 0.66, P  = 0.07). These results suggest the importance of non-producing periods, before maturity and during the dry period, on the subsequent and lifelong advantages of a good relationship between the stockperson and their animals.  相似文献   
129.
The abundance and distribution of Cu and Zn in spring water, irrigation water and sediment from the Fuchu Irrigation Canals, ground water for irrigation, rice plants and paddy soil at Tokyo University of Agriculture and Technology's Hommachi Farm were studied. The balance of Cu and Zn in the paddy field at the Hommachi Farm was investigated. The discharge of Cu and Zn influenced by human activities was observed in sediment of the Fuchu Irrigation Canal, and rice plants and paddy soil at the Hommachi Farm where irrigation water from the Fuchu Irrigation Canal was used until 1970. From Cu and Zn balance calculated, several hundred years are needed to decrease by half the present level of these metals at the Hommachi Farm.  相似文献   
130.
Maintaining genetic diversity and inbreeding control are important in Japanese Black cattle production, especially in remote areas such as the islands of Okinawa Prefecture. Using a single-nucleotide polymorphism (SNP) array, we evaluated the genetic diversity and genomic inbreeding in Japanese Black cows from the islands of Okinawa Prefecture and compared them to those from other locations across Japan. Linkage disequilibrium decay was slower in cows in the islands of Okinawa Prefecture. The estimated effective population size declined over time in both populations. The genomic inbreeding coefficient (FROH) was estimated using long stretches of consecutive homozygous SNPs (runs of homozygosity; ROH). FROH was higher in the cows on the islands of Okinawa Prefecture than on other locations. In total, 818 ROH fragments, including those containing NCAPG and PLAG1, which are major quantitative trait loci for carcass weight in Japanese Black cattle, were present at significantly higher frequencies in cows in the islands of Okinawa Prefecture. This suggests that the ROH fragments are under strong selection and that cows in the islands of Okinawa Prefecture have low genetic diversity and high genomic inbreeding relative to those at other locations. SNP arrays are useful tools for evaluating genetic diversity and genomic inbreeding in cattle.  相似文献   
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