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1.
Hritcu  Lucian  Bagci  Eyup  Aydin  Emel  Mihasan  Marius 《Neurochemical research》2015,40(9):1799-1809
Neurochemical Research - Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains,...  相似文献   
2.
Dissection of the genetic basis of wheat ionome is crucial for understanding the physiological and biochemical processes underlying mineral accumulation in seeds, as well as for efficient crop breeding. Most of the elements essential for plants are metals stored in seeds as chelate complexes with phytic acid or sulfur‐containing compounds. We assume that the involvement of phosphorus and sulfur in metal chelation is the reason for strong phenotypic correlations within ionome. Adjustment of element concentrations for the effect of variation in phosphorus and sulfur seed content resulted in drastic change of phenotypic correlations between the elements. The genetic architecture of wheat grain ionome was characterized by quantitative trait loci (QTL) analysis using a cross between durum and wild emmer wheat. QTL analysis of the adjusted traits and two‐trait analysis of the initial traits paired with either P or S considerably improved QTL detection power and accuracy, resulting in the identification of 105 QTLs and 617 QTL effects for 11 elements. Candidate gene search revealed some potential functional associations between QTLs and corresponding genes within their intervals. Thus, we have shown that accounting for variation in P and S is crucial for understanding of the physiological and genetic regulation of mineral composition of wheat grain ionome and can be implemented for other plants.  相似文献   
3.
Turbot, Scophthalmus maximus, is a commercially important demersal flatfish species distributed throughout the Black Sea. Several studies performed locally with a limited number of specimens using both mitochondrial DNA (mtDNA) and microsatellite markers evidenced notable genetic variation among populations. However, comprehensive population genetic studies are required to help management of the species in the Black Sea. In the present study eight microsatellite loci were used to resolve the population structure of 414 turbot samples collected from 12 sites across the Black Sea. Moreover, two mtDNA genes, COI and Cyt-b, were used for taxonomic identification. Microsatellite markers of Smax-04 and B12-I GT14 were excluded from analysis due to scoring issues. Data analysis was performed with the remaining six loci. Loci were highly polymorphic (average of 17.8 alleles per locus), indicating high genetic variability. Locus 3/20CA17, with high null allele frequency (>30%), significantly deviated from HW equilibrium. Pairwise comparison of the FST index showed significant differences between most of the surveyed sampling sites (P < 0.01). Cluster analysis evidenced the presence of three genetic groups among sampling sites. Significant genetic differentiation between Northern (Sea of Azov and Crimea) and Southern (Turkish Black Sea Coast) Black Sea sampling sites were detected. The Mantel test supported an isolation by distance model of population structure. These findings are vital for long-term sustainable management of the species and development of conservation programs. Moreover, generated mtDNA sequences would be useful for the establishment of a database for S. maximus.  相似文献   
4.
Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe.  相似文献   
5.
Micronutrient malnutrition is a growing concern in the developing world, resulting in diverse health and social problems, such as mental retardations, impairments of the immune system and overall poor health. In recent years, the zinc (Zn) deficiency problem has received increasing attention and appears to be the most serious micronutrient deficiency together with vitamin A deficiency. Zinc deficiency is particularly widespread among children and represents a major cause of child death in the world. In countries where Zn deficiency is well documented as an important public health problem, cereal-based foods are the predominant source of daily calorie and protein intake. Because the concentration of Zn in cereal crops is inherently very low, growing cereals on potentially Zn-deficient soils further decreases grain Zn concentrations. It is, therefore, not surprising that high Zn deficiency incidence in humans occurs predominantly on areas where soils are deficient in plant-available Zn, as shown in many Southeast Asian countries. India has some of the most Zn-deficient soils in the world. Nearly 50% of cultivated soils in India are low in plant-available Zn; these soils are under intensive cultivation of wheat and rice with no or little application of Zn fertilizers. Consequently, cereal crops grown on such Zn-deficient soils contribute only marginally to daily Zn intake. In the rural areas of India, rice and wheat contributes nearly 75% of the daily calorie intake. These facts clearly point to an urgent need for improved Zn concentration of cereal grains in India. Recent calculations indicate that biofortification (enrichment) of rice and wheat grain with Zn, for example by breeding, may save lives of up to 48,000 children in India annually. Breeding new cereal genotypes for high grain Zn concentration is the most realistic and cost-effective strategy to address the problem. However, this strategy is a long-term one, and the size of plant-available Zn pools in soils may greatly affect the capacity of Zn-efficient (biofortified) cultivars to take up Zn and accumulate it in grains. Therefore, application of Zn-containing fertilizers represents a quick and effective approach to biofortifying cereal grains with Zn, thus being an excellent complementary tool to the breeding strategy for successful biofortification of cereals with Zn. Increasing evidence is available from field trials showing that soil and/or foliar application of Zn fertilizers improves grain Zn concentration up to 2- or 3-fold. In the countries where Zn deficiency is both a public health issue and an important soil constraint to crop production, like in India, enrichment of widely applied fertilizers with Zn would be an excellent investment for improving grain Zn while contributing to increased crop production. Recent work by the scientists of the Indian Agricultural Research Institute indicates that the use of Zn-enriched urea in rice and wheat significantly improves both grain Zn concentration and grain yield. It is obvious that enrichment of widely applied fertilizers with Zn and/or foliar application of Zn fertilizers appear to be a high priority with the strongest potential to alleviate Zn deficiency-related problems in India. A Government action and policy plan for enrichment of selected major fertilizers with Zn is required urgently.  相似文献   
6.

Aims

Heat stress is a growing concern in crop production because of global warming. In many cropping systems heat stress often occurs simultaneously with other environmental stress factors such as mineral nutrient deficiencies. This study aimed to investigate the role of adequate magnesium (Mg) nutrition in mitigating the detrimental effects of heat stress on wheat (Triticum aestivum) and maize (Zea mays).

Methods

Wheat and maize plants were grown in solution culture with low or adequate Mg supply at 25/22 °C (light/dark). Half of the plants were, then, exposed to heat stress at 35/28 °C (light/dark). Development of leaf chlorosis and changes in root and shoot growth, chlorophyll and Mg concentrations as well as the activities of major antioxidative enzymes were quantified in the experimental plants. Additionally, maize plants were analyzed for the specific weights (e.g., dry or fresh weight per a given leaf surface area) and soluble carbohydrate concentrations of sink and source leaves.

Results

Visual leaf symptoms of Mg deficiency were aggravated in wheat and maize when exposed to heat stress. In both species, root growth was more sensitive to Mg deficiency than shoot growth, and the shoot-to-root ratios peaked when heat stress was combined with Mg deficiency. Magnesium deficiency markedly reduced soluble carbohydrate concentrations in young leaf; but resulted in substantial increase in source leaves. Magnesium deficiency also increased activities of antioxidative enzymes, especially when combined with heat stress. The highest activities of superoxide dismutase (up to 80 % above the control), glutathione reductase (up to 250 % above the control) and ascorbate peroxidase (up to 300 % above the control) were measured when Mg-deficient plants were subjected to heat, indicating stimulated formation of reactive oxygen species (ROS) in Mg deficient leaves under heat stress.

Conclusions

Magnesium deficiency increases susceptibility of wheat and maize plants to heat stress, probably by increasing oxidative cellular damage caused by ROS. Ensuring a sufficiently high Mg supply for crop plants through Mg fertilization is a critical factor for minimizing heat-related losses in crop production.  相似文献   
7.
Since the 1990s, blood donors have been scanned for anti-hepatitis C virus (anti-HCV) antibodies, which can be defined by enzyme immunoassay as a screening test. In this population, false-reactive ratios have been high. Recently, some authors have aimed to find a cutoff value for anti-HCV different from those established by test manufacturers to predict HCV infection. In this study, 321 patients, after two repeating tests, had reactive results in s/co <10 titers on anti-HCV test. The patients were 29.6 % (n?=?95) in women and 70.4 % (n?=?226) in men. The patients were classified into three groups by Western blot (WB) results (PS, positive; NG, negative; and ID, indeterminate). The average anti-HCV titer of the whole group was 2.61?±?1.96. Anti-HCV titers of subgroups were 2.43?±?1.95 in NG, 4.93?±?2.53 in PS, and 2.50?±?1.65 in ID (p?<?0.001). There was a significant difference between NG and PS and between PS and ID subgroups (p?<?0.001). There was a positive correlation between WB and anti-HCV titers in all patients (r?=?0.298, p?<?0.001), in women (r?=?0.282, p?<?0.001), and in men (r?=?0.337, p?=?0.002). According to receiver operator characteristic curve analysis, the cutoff value of anti-HCV titer to predict hepatitis C infection was >2.61 s/co, with 74.1 % sensitivity and 71.6 % specificity (area under the curve, 0.820; 95 % confidence interval, 0.753 to 0.887). We suggest that an effective cutoff value for anti-HCV other than that established by the manufacturer cannot be assigned to predict hepatitis C infection for blood donors in low-prevalence areas.  相似文献   
8.
Erenoglu  B.  Nikolic  M.  Römheld  V.  Cakmak  I. 《Plant and Soil》2002,241(2):251-257
Using two bread wheat (Triticum aestivum) and two durum wheat (Triticum durum) cultivars differing in zinc (Zn) efficiency, uptake and translocation of foliar-applied 65Zn were studied to characterize the role of Zn nutritional status of plants on the extent of phloem mobility of Zn and to determine the relationship between phloem mobility of Zn and Zn efficiency of the used wheat cultivars. Irrespective of leaf age and Zn nutritional status of plants, all cultivars showed similar Zn uptake rates with application of 65ZnSO4 to leaf strips in a short-term experiment. Also with supply of 65ZnSO4 by immersing the tip (3 cm) of the oldest leaf of intact plants, no differences in Zn uptake were observed among and within both wheat species. Further, Zn nutritional status did not affect total uptake of foliar applied Zn. However, Zn-deficient plants translocated more 65Zn from the treated leaf to the roots and remainder parts of shoots. In Zn-deficient plants about 40% of the total absorbed 65Zn was translocated from the treated leaf to the roots and remainder parts of shoots within 8 days while in Zn-sufficient plants the proportion of the translocated 65Zn of the total absorbed 65Zn was about 25%. Although differences in Zn efficiency existed between the cultivars did not affect the translocation and distribution of 65Zn between roots and shoots. Bread wheats compared to durum wheats, tended to accumulate more 65Zn in shoots and less 65Zn in roots, particularly under Zn-deficient conditions. The results indicate that differences in expression of Zn efficiency between and within durum and bread wheats are not related to translocation or distribution of foliar-applied 65Zn within plants. Differential compartementation of Zn at the cellular levels is discussed as a possible factor determining genotypic variation in Zn efficiency within wheat.  相似文献   
9.
Using three diploid (Triticum monococcum, AA), three tetraploid (Triticum turgidum, BBAA), two hexaploid (Triticum aestivum and Triticum compactum, BBAADD) wheats and two Aegilops tauschii (DD) genotypes, experiments were carried out under controlled environmental conditions in nutrient solution (i) to study the relationships between the rates of phytosiderophore (PS) release from the roots and the tolerance of diploid, tetraploid, and hexaploid wheats and AE: tauschii to zinc (Zn) and iron (Fe) deficiencies, and (ii) to assess the role of different genomes in PS release from roots under different regimes of Zn and Fe supply. Phytosiderophores released from roots were determined both by measurement of Cu mobilized from a Cu-loaded resin and identification by using HPLC analysis. Compared to tetraploid wheats, diploid and hexaploid wheats were less affected by Zn deficiency as judged from the severity of leaf symptoms. Aegilops tauschii showed very slight Zn deficiency symptoms possibly due to its slower growth rate. Under Fe-deficient conditions, all wheat genotypes used were similarly chlorotic; however, development of chlorosis was first observed in tetraploid wheats. Correlation between PS release rate determined by Cu-mobilization test and HPLC analysis was highly significant. According to HPLC analysis, all genotypes of Triticum and AE: tauschii species released only one PS, 2'-deoxymugineic acid, both under Fe and Zn deficiency. Under Zn deficiency, rates of PS release in tetraploid wheats averaged 1 micromol x (30 plants)(-1) x (3 h)(-1), while in hexaploid wheats rate of PS release was around 14 micromol x (30 plants)(-1) x (3 h)(-1). Diploid wheats and AE: tauschii accessions behaved similarly in their capacity to release PS and intermediate between tetraploid and hexaploid wheats regarding the PS release capacity. All Triticum and Aegilops species released more PS under Fe than Zn deficiency, particularly when the rate of PS release was expressed per unit dry weight of roots. On average, the rates of PS release under Fe deficiency were 3.0, 5.7, 8.4, and 16 micromol x (30 plants)(-1) x (3 h)(-1) for AE: tauschii, diploid, tetraploid and hexaploid wheats, respectively. The results of the present study show that the PS release mechanism in wheat is expressed effectively when three genomes, A, B and D, come together, indicating complementary action of the corresponding genes from A, B and D genomes to activate biosynthesis and release of PS.  相似文献   
10.

Background and Aims

Micronutrient malnutrition, particularly zinc and iron deficiency, afflicts over three billion people worldwide due to low dietary intake. In the current study, wild emmer wheat (Triticum turgidum ssp. dicoccoides), the progenitor of domesticated wheat, was tested for (1) genetic diversity in grain nutrient concentrations, (2) associations among grain nutrients and their relationships with plant productivity, and (3) the association of grain nutrients with the eco-geographical origin of wild emmer accessions.

Methods

A total of 154 genotypes, including wild emmer accessions from across the Near Eastern Fertile Crescent and diverse wheat cultivars, were characterized in this 2-year field study for grain protein, micronutrient (zinc, iron, copper and manganese) and macronutrient (calcium, magnesium, potassium, phosphorus and sulphur) concentrations.

Key Results

Wide genetic diversity was found among the wild emmer accessions for all grain nutrients. The concentrations of grain zinc, iron and protein in wild accessions were about two-fold greater than in the domesticated genotypes. Concentrations of these compounds were positively correlated with one another, with no clear association with plant productivity, suggesting that all three nutrients can be improved concurrently with no yield penalty. A subset of 12 populations revealed significant genetic variation between and within populations for all minerals. Association between soil characteristics at the site of collection and grain nutrient concentrations showed negative associations between soil clay content and grain protein and between soil-extractable zinc and grain zinc, the latter suggesting that the greatest potential for grain nutrient minerals lies in populations from micronutrient-deficient soils.

Conclusions

Wild emmer wheat germplasm offers unique opportunities to exploit favourable alleles for grain nutrient properties that were excluded from the domesticated wheat gene pool.  相似文献   
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