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31.
Transmission electron microscopic observation of forsterite (Mg(2)SiO(4)) shocked to peak pressures of 78 to 92 gigapascals revealed that forsterite breaks down to an assemblage of MgO plus MgSiO(3) glass. This strongly supports the interpretation that the high-pressure phase of forsterite under shock compression is due to the assemblage of MgSiO(3) perovskite plus MgO.  相似文献   
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The hydrogen-bonding properties of water-ethanol of alcoholic beverages and water-ethanol mixtures of the corresponding ethanol contents were examined on the basis of OH proton NMR chemical shifts and the Raman OH stretching spectra of water and ethanol. Japanese shochu, an unaged distilled spirit of 25% (v/v) alcoholic content made from various grains, was provided for the samples; it is a high-purity spirit as it contains only small amounts of dissolved components, like typical vodka, gin, and white rum. The hydrogen-bonding structure in shochu containing some acids was found to be different from that of the water-ethanol mixture with corresponding ethanol content. It was concluded that, by the presence of small amounts of organic acids, the water-ethanol hydrogen-bonding structure was strengthened, at the same time, the proton exchange between water and ethanol molecules was promoted in shochu, compared with the water-ethanol mixture. The NMR chemical shifts of fruit cocktail drinks suggested that the hydrogen bonding of water-ethanol in the solution was developed by organic acids and (poly)phenols from fruit juices.  相似文献   
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The coat of a goat, like that of many mammalian species, consists of an outer coat of coarse hairs and an under coat of fine, downy hairs. The coarse guard hairs are produced by primary follicles and the finer cashmere hairs by secondary follicles. We previously reported that hair keratins are components of cashmere hair, and proteomic analysis revealed that their expression is elevated in winter coat hair. To determine detailed characterization, we have cloned keratin 33A gene, a major highly expressed keratin in winter, and then analyzed the expression of goat hair coat. By Western analysis, we detected that keratin 33A protein is expressed only in hair coat among the various goat tissues. Moreover, the expression level in winter has increased in cashmere high‐producing Korean native breed, whereas the expression levels between summer and winter had not changed in cashmere low‐producing Saanen. In addition, by immunohistochemistry we determined that keratin 33A is localized in the major cortex portion of cashmere fiber. These results confirm that keratin 33A is a structural protein of goat cashmere hair fiber.  相似文献   
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Wind erosion is a major contributor to desertification in the Sahel. Although three effective countermeasures for wind erosion (i.e. ridging, mulching with post-harvest crop residue, and windbreaks) have been proposed, they are not practical for Sahelian farmers. Therefore, we designed a new land management practice, termed the “Fallow Band System,” which can be used for both controlling wind erosion and improving soil fertility and crop production. This method does not impose additional expense and labor requirements on Sahelian farmers who are economically challenged and have limited manpower. The objective of this study was to evaluate the effects of this system on wind-erosion control and soil-fertility improvement. We conducted field experiments at the International Crops Research Institute for the Semi-Arid Tropics West and Central Africa and showed that (i) a fallow band can capture 74% of wind-blown soil particles and 58% of wind-blown coarse organic matter, which suggests that it can effectively control wind erosion, (ii) the amount of soil nutrients available for crops in a former fallow band was increased by the decomposition of trapped soil materials containing considerable amounts of nutrients, and (iii) the amount of soil water available for crops in a former fallow band was increased by the trapped wind-blown soil materials through improvement of rainwater infiltration into surface soil. These results lead to the conclusion that the “Fallow Band System” can be useful for preventing desertification and improving soil fertility in the Sahel, West Africa.  相似文献   
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Genome size (C value) is an important index for phylogenetic studies. Haliotidae (abalones) includes many species widely distributed throughout the world??s oceans, which makes this family interesting for phylogenetic studies. To examine Haliotidae phylogeny, we determined the C value and adenine and thymine base pair content (AT?%) of Haliotis discus hannai and H.?diversicolor aquatilis by using flow cytometry. The C values of H.?discus hannai and H.?diversicolor aquatilis were 1.84 and 1.45?pg, with AT?% of 62.3 and 66.3?%, respectively. These data represent the first report of abalones classified as Pacific Northwest (H.?discus hannai) and Indo-Pacific (H.?diversicolor aquatilis) groups, and provides new validation for previous theories related to Haliotidae phylogeny.  相似文献   
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To develop a high density linkage map in faba bean, a total of 1,363 FBES (Faba bean expressed sequence tag [EST]-derived simple sequence repeat [SSR]) markers were designed based on 5,090 non-redundant ESTs developed in this study. A total of 109 plants of a ‘Nubaria 2’ × ‘Misr 3’ F2 mapping population were used for map construction. Because the parents were not pure homozygous lines, the 109 F2 plants were divided into three subpopulations according to the original F1 plants. Linkage groups (LGs) generated in each subpopulation were integrated by commonly mapped markers. The integrated ‘Nubaria 2’ × ‘Misr 3’ map consisted of six LGs, representing a total length of 684.7 cM, with 552 loci. Of the mapped loci, 47% were generated from multi-loci diagnostic (MLD) markers. Alignment of homologous sequence pairs along each linkage group revealed obvious syntenic relationships between LGs in faba bean and the genomes of two model legumes, Lotus japonicus and Medicago truncatula. In a polymorphic analysis with ten Egyptian faba bean varieties, 78.9% (384/487) of the FBES markers showed polymorphisms. Along with the EST-SSR markers, the dense map developed in this study is expected to accelerate marker assisted breeding in faba bean.  相似文献   
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Rice fragrance is an important characteristic for Southeast Asian consumers, and fragrant landraces from Japan were first recorded in the 17th century. Principal component analysis clearly showed that Japanese fragrant landraces were genetically different from non-Japanese fragrant landraces. Japanese fragrant landraces were composed of six clades, none of which carried the most common fragrance mutation, an 8-bp deletion in exon 7 of Badh2. Fragrant landraces comprised two major groups carrying different Badh2 mutations. One group carried a known SNP at exon13 and the other a SNP at the exon1-intron1 junction as splicing donor site. The latter was considered to be a potential splicing mutant group as a novel allele at Badh2. Heterozygosity (He) scores in the two fragrant groups were not significantly different from non-fragrant landraces and modern cultivars. However, lower He scores were found around the Badh2 locus in the two groups. The potential splicing mutant group showed a more extended haplotype than the E13 SNP group. A likely causal factor responsible for loss of function is a novel splicing mutation allele that may have been generated quite recently. The fragrance allele has dispersed as a result of out-crossing under local environmental conditions.  相似文献   
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