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71.
Variation in bread wheat including pre and post green revolutions varieties of Pakistan along with landraces was investigated for high molecular weight Glutenin subunits (HMW Gs) encoded at three genes (Glu-A1, Glu-B1, Glu-D1) with SDS-PAGE. The germplasm was diverse and unique on the basis of HMW Gs compositions and out of 14 alleles detected at all the Glu-1 loci, three belonged to Glu-A1, nine to Glu-B1 and two to Glu-D1 locus. High variation was observed in the landraces and higher gene diversity was observed between the populations as compared to the gene diversity within populations, whereas a reverse pattern of gene diversity was observed when populations were pooled across the region (higher within the regions than between the regions). A lack of relationship between the HMW Gs diversity and the altitude of collection site was observed. A data base has been generated in this study which could be expanded/exploited for cultivar development or management of gene bank.  相似文献   
72.
多种植物提取物对小菜蛾产卵的驱避作用   总被引:3,自引:0,他引:3       下载免费PDF全文
小菜蛾仅取食为害十字花科植物,其他非嗜食植物的提取物对小菜蛾可能有好的控制作用,在温室内试验研究了14种常见植物的提取物对小菜蛾雌虫的产卵驱避作用,绝大部分供试植物的提取物可减少小菜蛾的落卵量40%以上,作用最强的是尾叶桉的抽提物,喷施24h后卵降低率达65.52%。植物提取物对小菜蛾雌虫的产卵驱避作用48h后下降,卵减少率最高为飞机草的抽提物,达52.91%,非嗜食植物次生物质在小菜蛾的控制中会有良好的前景。  相似文献   
73.
Medulloblastoma (MB) is the most common malignant brain tumor of children. To identify the genetic alterations in this tumor type, we searched for copy number alterations using high-density microarrays and sequenced all known protein-coding genes and microRNA genes using Sanger sequencing in a set of 22 MBs. We found that, on average, each tumor had 11 gene alterations, fewer by a factor of 5 to 10 than in the adult solid tumors that have been sequenced to date. In addition to alterations in the Hedgehog and Wnt pathways, our analysis led to the discovery of genes not previously known to be altered in MBs. Most notably, inactivating mutations of the histone-lysine N-methyltransferase genes MLL2 or MLL3 were identified in 16% of MB patients. These results demonstrate key differences between the genetic landscapes of adult and childhood cancers, highlight dysregulation of developmental pathways as an important mechanism underlying MBs, and identify a role for a specific type of histone methylation in human tumorigenesis.  相似文献   
74.
Nitrate reductase(NR) is an important enzyme for nitrate assimilation in plants, and post-translational phosphorylation regulates NR activity. To evaluate the impact of the dephosphorylation of nitrate reductase 1(NIA1) protein on NR activity,nitrogen metabolism and plant growth, NIA1 phosphorylation site directed mutant lines(S532 D and S532 A) and an OsNia1 over-expression line(OE) were constructed, and the phenotype, NIA1 protein and its phosphorylation level, NR activity,nitrate metabolism a...  相似文献   
75.
Pakistan is well known for its basmati rice with long grain and aroma, as well as for non-basmati indica varieties; however average yield is lower as compared with other countries. Besides, cultural practices, the main reason for low productivity in Pakistan is that, local varieties are susceptible to different biotic and abiotic factors like insect pests, diseases, drought, and salinity. Different approaches have been undertaken in Pakistan to tackle these problems through traditional breeding of selection and crossing, mutation breeding, somaclonal variation as well as plant transformation studies in recent past. For variety development, the most successful examples arose from traditional breeding that produced famous basmati varieties like Basmati 370, Basmati 385 and Super basmati, and non-basmati varieties such as IRRI-6, DR-82, DR-83, DR-92, Swat-I and Swat-II, which earn a significant share of foreign exchange every year. Six varieties have also been developed through mutation breeding, and one through exploitation of somaclonal variation but their contribution to the national economy is not significant. On the other hand, no variety has been registered as commercial by plant transformation groups. This review discusses the problems and prospects of rice breeding with special emphasis on basmati rice in Pakistan particularly in Pakistani Punjab (a major producing area), as well as focuses on future research programs.  相似文献   
76.
Wheat leaf senescence is a developmental process that involves expressional changes in thousands of genes that ultimately impact grain protein content (GPC), gr...  相似文献   
77.
In recent years, there has been considerable interest in lectins from marine invertebrates. In this study, the biological activities of a lectin protein isolated from the eggs of Sea hare (Aplysia kurodai) were evaluated. The 40 kDa Aplysia kurodai egg lectin (or AKL-40) binds to D-galacturonic acid and D-galactose sugars similar to previously purified isotypes with various molecular weights (32/30 and 16 kDa). The N-terminal sequence of AKL-40 was similar to other sea hare egg lectins. The lectin was shown to be moderately toxic to brine shrimp nauplii, with an LC50 value of 63.63 µg/mL. It agglutinated Ehrlich ascites carcinoma cells and reduced their growth, up to 58.3% in vivo when injected into Swiss albino mice at a rate of 2 mg/kg/day. The morphology of these cells apparently changed due to AKL-40, while the expression of apoptosis-related genes (p53, Bax, and Bcl-XL) suggested a possible apoptotic pathway of cell death. AKL-40 also inhibited the growth of human erythroleukemia cells, probably via activating the MAPK/ERK pathway, but did not affect human B-lymphoma cells (Raji) or rat basophilic leukemia cells (RBL-1). In vitro, lectin suppressed the growth of Ehrlich ascites carcinoma and U937 cells by 37.9% and 31.8%, respectively. Along with strong antifungal activity against Talaromyces verruculosus, AKL showed antibacterial activity against Staphylococcus aureus, Shigella sonnei, and Bacillus cereus whereas the growth of Escherichia coli was not affected by the lectin. This study explores the antiproliferative and antimicrobial potentials of AKL as well as its involvement in embryo defense of sea hare.  相似文献   
78.
Raw and cooked samples of cultivars ofLens esculenta (Lentils),Pisum sativum (peas),Phaseolus vulgaris (beans),Phaseolus aureus (navy beans)Cicer arietnum (gram), andLathyrus sativus (dhal) as well as precooked commercial products were analysed for amino acids, trypsin inhibitor activity and in vitro protein digestibility. Of the fifteen samples used in the study one lentil sample, one pea sample, two gram samples and one sample of khesari dhal were from Bangladesh, one gram sample was from Sri Lanka. The other samples were obtained either in shops in Norway or from an industrial firm. The latter were also obtained precooked and dried. The two samples obtained in shops were used with hull and dehulled.Neither cooking by a Bangladeshi household procedure nor industrial precooking and drying had any effect on the amino acid contents of the samples.Cooking and precooking reduced the trypsin inhibitor activity of the raw samples more when the original activity was high then when it was low. The inhibitor activity was similar between samples after cooking.Cooking and precooking and drying increased the in vitro protein digestibility in all samples except in the lentils in which the digestibility was reduced.In the raw samples protein digestibility was negatively correlated with the trypsin inhibitor activity.  相似文献   
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