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111.
The objective was to study the potential of grain by-products (husk) of grains such as wheat (Triticum aestivum L; German name is Weizen) and rice (Oryza sativa) as reinforcements for thermoplastics as an alternative to or in combination with wood fibres. Prior to composites preparation, the chemical components of fibres such as cellulose, hemi-cellulose, lignin, starch, protein and fat were measured and the surface chemistry and functionality of grain by-products were studied using EDX and FT-IR. Structural constituents (cellulose, starch) were found in wheat husk (W) equal 42%, in rice husk 50% and in soft wood 42%, respectively. Thermal degradation characteristics, the bulk density, water absorption and the solubility index were also investigated. Wheat husk (W) and rice husk were found thermally stable at temperatures as low as 178 °C and 208 °C, respectively. The particle morphology and particle size were investigated using microscopy. Water absorption properties of the fibres were studied to evaluate the viability of these fibres as reinforcements. Polypropylene composites were fabricated using a high speed mixer and an ensuing injection moulding process with 40 wt% fibre. The tensile and Charpy impact strength of the resulting composites were investigated. The tensile elongation at break was found to 75% for wheat husk (W) composites and 23% for rice husk composites better than soft wood composites. Rice husk composites showed 13% better Charpy impact strength than soft wood composites. Due to coupling agent, tensile strength of composites found to improve 25% for soft wood, 35% for wheat husk (W) and 45% for rice husk.  相似文献   
112.
113.
Development and characteristics of ω-gliadin-free wheat genotypes   总被引:1,自引:0,他引:1  
Omega gliadin proteins are one of the most allergenic components of wheat gluten. Proteins of the ω-5 subgroup are recognized as main allergens causing wheat dependent exercise induced anaphylaxis—the most dangerous, life-threatening IgE mediated food allergy. A set of wheat genotypes lacking all ω-gliadins has been developed by cumulating inactive gene variants in three gliadin coding loci (Gli A1, Gli B1 and Gli D1), using traditional plant breeding methods. Endosperm proteins of ω-gliadin-free genotypes were compared to a control genotype containing all ω-gliadins by A-PAGE, SDS-PAGE and RP-HPLC. A considerable decrease (about 30 %) of gliadin immunoreactivity as a consequence of ω-gliadin elimination was demonstrated by ELISA, using sera of ten patients allergic to gluten. Preliminary evaluation of the technological properties of the ω-gliadin-free genotype by the SDS sedimentation test suggests that elimination of all ω-gliadins may also significantly improve wheat bread making quality.  相似文献   
114.
Journal of Plant Diseases and Protection - The aim of this study was to determine thrips abundance, species composition and seasonal dynamics on two genetically modified types of linseed, i.e.,...  相似文献   
115.
Retention of fetal membranes is one of the most common life-threatening peripartum problems; however, its etiology is still unknown. Draft mares are more likely to retain fetal membranes than other breeds of mares. Because a strong connection between the fetal membranes and the endometrium has been observed in cases of retention, we studied the changes in the endometrium and the allantochorion of heavy draft mares with this condition. Tissue samples were taken from 90 mares that retained the fetal membranes and from 21 that did not. Retained fetal membranes were associated with adhesion of the allantochorion to the endometrium in 88% of the mares; this adhesion depended on the following factors: occurrence of fibrosis both in the lamina propria of the allantochorial villi and in the allantochorial stromal connective tissue, overdevelopment of the allantochorial stromal connective tissue, oversized allantochorial epithelial cells, and sparser and less-branched allantochorial villi.  相似文献   
116.
Białowieża Primeval Forest lies within the boreal part of the Norway spruce range, which, according to pollen data, was formed by a refugium located in the Russian Upland. However, recent genetic studies have indicated that spruce from the Eastern Carpathian refugium also occurs in Białowieża Forest. In order to investigate whether the Norway spruce from the Eastern Carpathian refugium migrated naturally into the boreal part of the Norway spruce range, we assessed the refugial origin of 234 of the oldest Norway spruce individuals from Białowieża Forest using mitochondrial marker mt15-D02. Out of the trees that we studied, 64.8% carried mitotype 1, which is specific to the Carpathian refugium, while 35.2% had mitotype 3, specific to the Russian refugium. Our genetic analysis, combined with historical data on forest management in this part of Europe, argues for a natural contribution of spruce from the Eastern Carpathian refugium during postglacial recolonization of Białowieża Primeval Forest.  相似文献   
117.
The present and past population status of oak (Quercus robur) in the Bia?owie?a National Park preserve (BNP) was analyzed with respect to the historic use of the ecosystem. I assessed average parameters (density, dbh distribution, differences between habitat categories) of the oak population in the whole BNP preserve, and performed detailed analyses of local populations on three 26.5-ha and one 3.5-ha plots, representing eutrophic sites of deciduous forest (3) and a mesotrophic site of mixed forest (1). Based on the tree ring data, I reconstructed the historic dbh distribution back to 1750–1825. The results of the reconstruction confirm the early 1800s expert account and the 1889 forestry survey report. The high oak concentration in eutrophic habitats are legacies of either active game management (e.g., bison habitat improvement measures, supplementary feeding), forest recovery after the ban on forest industries (baking potash, tar, charcoal), or abandonment of inner small farms. The emergence of oak on poorer sites in the mid 1800s coincides with the ban on use of fire—a common practice that earlier had perpetuated the dominating position of fire-resistant pine. The present oak regeneration in declining spruce stands is a further step of the forest natural adaptation to environmental changes. The study supports the view that BNP is a remnant of an ecosystem substantially shaped by human uses. Modern forestry, as practiced in the managed part of the Bia?owie?a forest, does not mimic either natural processes (as observed in BNP) or historic forest uses.  相似文献   
118.
Acute phase proteins (APP) have been described as useful for assessing health in human and animal patients, as they closely reflect the acute phase reaction (APR). In humans and dogs a reaction analogous to APR has also been described after prolonged or strenuous exercise. The aim of this study was to determine, if similar reactions occur in endurance horses after limited and long distance rides. Seventeen horses that successfully completed various distance competitions were tested. Routine haematological and biochemical tests were performed and the concentrations of serum amyloid A (SAA), C-reactive protein (CRP) and haptoglobin were measured. Typical endurance exercise-induced haematological and biochemical changes were observed in all horses, regardless the distance. After long distance rides, the level of SAA markedly increased, but CRP and haptoglobin concentrations remained unchanged. After limited distance rides no changes in the levels of APPs were noted. Exercise-induced APR in horses occurred only after prolonged, strenuous exertion, and differed from APR in inflammation in that only SAA concentration was increased.  相似文献   
119.
Conglutinin is a high molecular-weight lectin originally detected in bovine serum. It belongs to the family of collectins that bind sugar residues in a Ca2+-dependent manner and are effector molecules in innate immunity. Conglutinin appears to play an important role in immune defense mechanisms, showing antiviral and antibacterial activities when tested in vivo and in vitro. The present study evaluated the effect of conglutinin on the respiratory bursts in bovine peripheral phagocytes. Using nitroblue tetrazolium and hydrogen peroxide assays, we showed that sugar ligand-bound conglutinin stimulated the production of superoxide and H2O2 in granulocytes whereas the non-sugar-bound form of conglutinin inhibited these processes. These results indicate that both forms of conglutinin are able to interact with surface leukocyte receptors but have opposite effects on phagocytic activity. Our findings suggest that conglutinin bound to sugar residues on microbial surfaces can induce oxygen burst in phagocytes, and thereby mediates the elimination of pathogens and prevents the spread of infection.  相似文献   
120.
Acrosin from turkey spermatozoa has been recently identified and characterized. In this study, we reported the identification of second form of acrosin (acrosin II) in turkey spermatozoa. Using the three-step isolation procedure, we purified and characterized the acrosin II from a turkey spermatozoa extract. N-terminal Edman sequencing allowed the identification of the 24 amino acids from the internal part of acrosin II: SLQEYVEPYRVLQEAKVQLIDLNL. Thanks to homology alignment, we concluded that acrosin II is an acrosin-like protein similar to avian acrosin, including turkey acrosin. The molecular mass of acrosin II estimated by mass spectrometry was 30.869 kDa. During chromatofocusing, the acrosin II was eluted at pH range from 6.4 to 6.2. Acrosin II was found to be a glycoprotein. The glucosamine and galactosamine were present in carbohydrate structures of acrosin II. Acrosin II is characterized by similar physicochemical characteristics like previously identified bird acrosins, including acrosin from turkey spermatozoa. Similarities between turkey acrosins were also confirmed immunologically by western blot analysis. It can be suggested that two forms of serine proteinase similar to acrosin exist in turkey spermatozoa. These phenomena of both acrosins in spermatozoa agree with the concept of functional redundancy of proteolytic enzymes in the reproductive system. These redundancies may be important for efficient fertilization in turkey.  相似文献   
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