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1.
This study aimed to investigate the possible causes for inconsistent performances of upland New Rice for Africa (NERICA) varieties in uplands and lowlands, while identifying important determinants in grain yield under deficient soil moisture. We compared the growth and yield of NERICA 1 and NERICA 5 to those of Yumenohatamochi, a Japanese upland variety, and Hinohikari, a Japanese lowland variety, subjected to different water management regimes (continually flooded, supplementary irrigation, and non-irrigation). Under conditions of deficient soil moisture, panicle number per square meter, spikelet number per panicle, and 1000-grain weight of NERICAs decreased, whereas the panicle number of the Japanese varieties experienced little change. In contrast, the grain filling ratio was unaffected by water management, irrespective of variety. The primary source of yield reduction under low soil water conditions was a decrease in spikelet number per panicle, and water stress intensity was the primary factor for the degree of this reduction. Variation in the abortion of secondary rachis-branches caused differences between NERICAs in their spikelet number response to soil moisture deficiency. The inconsistency in NERICA performance across uplands vs. lowlands can be partially attributed to variation in yield response to low soil water conditions. Moreover, water stress intensity and the presence of a water gradient along the vertical soil profile may combine to affect the fluctuation in NERICA performance under upland conditions.  相似文献   
2.
Information on primary growth behavior after planting is required for mixed-plantation revegetation using broad-leaved species. To estimate primary growth, especially from the perspective of crown coverage and changing growth rates, we examined the growth and survival of four broad-leaved species that are frequently used in erosion-control plantations in Japan. The species studied were Myrica rubra Sieb. et Zucc., Alnus pendula Matsum., Quercus glauca Thunb., and Q. serrata Thunb. The survival, height, and basal diameter of planted trees were measured over a 4-year period, and crown area was calculated over a 3-year period. We found a negative relationship between relative growth rate (RGR) and survival rate, suggesting that fast growth may be fatal when resources are severely limited. The relative height growth rate (RHGR) of A. pendula was especially high during the early period of the study (1997–1999) and then drastically declined, whereas the opposite tendency was observed in Q. glauca. The results of stem allometry analyses conformed to the specific relationships between height growth and diameter growth of the four species; increases in stem thickness based on height increments were smaller in the pioneer species A. pendula. Between-species differences in coverage per planted tree (mean crown area multiplied by survival rate) were small as a result of the negative relationship between coverage area and survival rate.  相似文献   
3.
The stepwise hot water extraction of soybeans, which were extractions in a series of procedures of whole soybean seeds, dehulled and sliced ones, and pressed ones carried out by autoclaving, was investigated to study the localization in the seed and their characteristics. The characteristics of each extraction were studied by HPLC, SDS-PAGE, components analysis, microscopic observation, and effect for some enzymes. Carbohydrates were easier to extract than protein. In the extractions, the ratio of uronic acid per total sugar was constantly about 0.3. A comparison of these extracts, soybean milk, extraction from defatted soybean meal, and soybean milk residues was also carried out, and the characteristics and the localization were investigated. Mid-sized proteins in soybean milk were easy to extract. However, hardly any high molecular weight proteins or high molecular weight carbohydrates were extracted. The proteins and carbohydrates were considered to be localized in the middle lamella and in the protein and/or oil bodies of the cell, and the proteins and carbohydrates were gradually extracted through seed and cell breaking. Gelation was observed only in the boiled extracts from whole seeds. Pepsin and trypsin digests of the high molecular weight protein had inhibitory activity against the angiotensin I converting enzyme.  相似文献   
4.
Parasporal inclusion proteins produced by Bacillus thuringiensis strain A1470 exhibit strong cytotoxicity against human leukemic T cells when activated by protease treatment. One of the cytotoxic proteins was separated by anion exchange chromatography and gel filtration chromatography and designated Cry45Aa. Its gene was then expressed in recombinant Escherichia coli, in which the Cry45Aa precursor was accumulated in an inclusion body. It was solubilized in sodium carbonate buffer and processed with proteinase K, and cytotoxic activities of the protein against various mammalian cell lines were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide assay. The protein exhibited high cytotoxic activity against CACO-2, Sawano, MOLT-4, TCS, and HL60 cells and moderate activity against U-937 DE-4, PC12, and HepG2 cells. On the other hand, the EC50 values against Jurkat, K562, HeLa, A549, Vero, COS-7, NIH3T3, CHO, and four normal tissue cells (human primary hepatocyte cells, UtSMC, MRC-5, and normal T cells) were >2 microg/mL.  相似文献   
5.
A field survey and a laboratory experiment were conducted to examine ontogenetic shifts in habitat and diet of the turban snail Turbo cornutus. The main habitat of turban snail juveniles smaller than 10 mm shell height (SH) was turfs of articulated coralline algae, and that of adults larger than 50 mm SH was kelp beds of Ecklonia bicyclis and Ecklonia cava. However, the ontogenetic habitat shift during the juvenile stage of 20–50 mm SH was unclear. From the results of a long-term feeding experiment and stable isotope analysis, the gelidiacean alga Gelidium elegans was assumed to be more important as a food source for juvenile turban snail than E. cava in the field. However, the frequency of individuals inhabiting gelidiacean algal turfs was low in both juvenile and adult stages. Thus, the ontogenetic shifts in habitat and diet did not coincide and other factors, i.e., daytime refuge, are important. As the growth rate was higher in the juveniles fed on the two algal species than those fed on single algal species, co-occurrence of various algal habitats in rocky shore ecosystems as a coastal ecosystem complex may enhance growth of turban snail juveniles feeding on a combination of different algal species.  相似文献   
6.
Leaf nitrogen nutrition of hinoki cypress (Chamaecyparis obtusa Endlicher) was investigated at three positions along a slope over a period of 3 years. At each slope position, nitrogen properties were compared in patch-cut plots (0.06–0.09 ha) and uncut control plots (0.04 ha). Nitrogen cycling at the lower slope was characterized by a higher rate of soil nitrogen mineralization, and higher nitrogen concentration in fresh leaves and leaf-litter. The soil nitrogen mineralization rate and fresh-leaf nitrogen concentration in the patch-cut plots were higher than those in the control plots. However, leaf-litter nitrogen concentration did not differ between the patch-cut and control plots. The results suggest that slope position strongly affects leaf nitrogen nutrition of hinoki cypress and soil nitrogen availability. By contrast, patch cutting does not affect leaf-litter nitrogen concentration. These findings indicated that hinoki cypress would not enhance forest nitrogen cycling through changes in leaf-litter nitrogen concentration after patch cutting.  相似文献   
7.
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface.  相似文献   
8.
Lodging tolerance (LT) is an important trait for high yield and combine-harvesting efficiency in soybean [Glycine max (L.) Merr.]. Many previous studies have investigated quantitative trait loci (QTLs) for lodging score (LS) in soybean. Most of the investigated QTLs were located in the proximal region of maturity or growth habit loci. The aim of this study was to identify genetic factors for LT not associated with maturity or growth habit. QTL analysis was performed using a recombinant inbred line (RIL) population derived from a cross between ‘Toyoharuka’ (TH), a lodging-tolerant cultivar, and ‘Toyomusume’ (TM). The genotypes of TH and TM were estimated as both e1e2E3E4 and dt1. The average LS over 4 years was used for QTL analysis, identifying a major and stable QTL, qLS19-1, on chromosome 19. The LS of the near-isogenic line (NIL) with the TH allele at Sat_099, the nearest marker to qLS19-1, was significantly lower than the NIL with the TM allele at that position. The TH allele at Sat_099 rarely had a negative influence on seed yield or other agronomic traits in both NILs and the TM-backcrossed lines. Our results suggest that marker-assisted selection for qLS19-1 is effective for improving LT in breeding programs.  相似文献   
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