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61.
Wheat seed storage proteins, especially glutenins and gliadins, have unique functional properties giving rise to a wide array of food products for human consumption. The wheat seed storage proteins, however, are also the most common cause of food-related allergies and intolerances, and it has become crucially important to understand their composition, variation and functional properties and interface this knowledge with the grain handling industry as well as the breeders. This review focuses on advances in understanding the genetics and function of storage proteins and their application in wheat breeding programs. These include: (1) The development and validation of high-throughput molecular marker systems for defining the composition and variation of low molecular weight glutenin subunits (LMW-GS) genes and a summary of the more than 30 gene-specific markers for rapid screening in wheat breeding programs; (2) The identification of more than 100 alleles of storage proteins in wild species provide candidate genes for future quality improvement; (3) The documentation of quality effects of individual LMW-GS and HMW-GS for improving end-use quality; and (4) The analysis of α-gliadin genes on chromosomes 6A and 6D with non-toxic epitopes as potential targets to develop less toxic cultivars for people with celiac disease. Genomic and proteomic technologies that will continue to provide new tools for understanding variation and function of seed storage proteins in wheat are discussed.  相似文献   
62.
Nucleotide sequence of the Rasheed rat sarcoma virus oncogene: new mutations   总被引:16,自引:0,他引:16  
The nucleotide sequence of the oncogene of the Rasheed strain of rat sarcoma virus was determined. The oncogene (Ra-v-ras) encodes a 29,000-dalton (p29) transforming protein. This protein is distinct from the immunologically related 21,000-dalton protein (p21) of the Harvey murine sarcoma virus in its amino terminus and in having additional mutations in its carboxyl terminus. Although the functional significance of these changes is unknown, they appear to occur only in rat sarcoma virus.  相似文献   
63.
Temperature is considered as an important environmental factor, and the increasing water temperature resulting from global warming is a great concern. The present study was conducted to examine the effects of elevated water temperature on growth, hemato‐biochemical parameters in Nile tilapia, Oreochromis niloticus acclimatized to three temperatures (31°C, 34°C and 37°C) for 60 days. Additionally, erythrocytic cellular abnormalities (ECA) and erythrocytic nuclear abnormalities (ENA) tests were assayed using peripheral erythrocytes after exposure to the three temperatures. Fish were sacrificed on days 7, 15, 30 and 60 of exposure. Growth performances viz., weight gain, % weight gain and specific growth rate (SGR) showed decreasing tendency at 34°C but significantly declined at 37°C compared to 31°C. The abundance of haemoglobin (Hb) and red blood cells (RBCs) significantly decreased in response to temperature increases, while white blood cells (WBCs) displayed the opposite response. At days 7 and 15, blood glucose levels significantly increased in response to the temperature increase, while at days 30 and 60 glucose declined. Frequencies of ECA and ENA were significantly enhanced at the highest temperature throughout the experimental period. Dissolved oxygen decreased and free CO2 increased significantly with increasing temperature throughout the study period. The present study revealed that temperatures higher than 34°C may be hazardous to O. niloticus.  相似文献   
64.
European Journal of Plant Pathology - Sclerotinia is a phytopathogenic genus of fungi that form sclerotia: black, hard, seed-like functioning bodies. Sclerotinia sclerotiorum and Sclerotinia minor...  相似文献   
65.
Drosophila suzukii (Matsumura, 1931) is here reported for the first time from the high-altitude and cold arid region of Ladakh, which is a Northwestern Himalayan region of India and is the second coldest inhabited place in the world. The species is emerging in the Ladakh region as a serious apricot pest, causing a considerable amount of economic loss.  相似文献   
66.
Stocking of all‐male fingerling produced by direct administration of male hormone 17‐α‐methyltestosterone is the most preferred method for present‐day aquaculture of the Nile tilapia Oreochromis niloticus. However, due to the growing concern of negative impact of steroid hormone in food fish, production of ‘genetically male’ tilapia, which depends on the concrete and thorough understanding of sex determination, has long been a scientific curiosity. The objective of the present study was to identify reliable sex‐linked markers and to evaluate the applicability of those markers in terms of monosex production approach. ‘XY’ neofemales were produced by using synthetic oestrogen and identified through selective breeding and progeny testing. Three females with progeny not deviating from 3:1 sex ratio (male:female) were designated as ‘XY’ neofemales and were used subsequently to produce putative YY progeny. Among the fifteen microsatellite markers tested, marker ARO172 was most informative in differentiating male and female genotypes. Twenty‐seven F2 fish from three families were identified as putative YY males based on marker genotyping, and four of them were crossed to produce F3 to validate marker association by progeny testing. The YY males produced 86%–100% male progeny indicating ARO172 a unique sex‐linked marker applicable in marker‐assisted selection.  相似文献   
67.
Components of green tea ( Camellia sinensis) have been of considerable interest in recent years because of their potential utility as pharmaceutical agents, particularly for their antioxidant and anticarcinogenic activity. Responding to the increasing scientific validation of numerous health benefits of tea, a comprehensive approach was adopted to carry out analysis for the quality assessment of flavonoids in tea samples of different origins. For this purpose, extraction, separation, and mass spectrometric parameters were optimized. Extraction methods evaluated include reflux extraction, a modified accelerated solvent extraction (ASE), namely, Aquasolv extraction, and microwave-assisted extraction (MAE) using different percentages of solvents. Separation was performed by a specifically developed reversed phase high-performance liquid chromatography (RP-HPLC) method using different C18 and C8 stationary phases. Optimization of extraction techniques clearly proved the performance of MAE, which delivered highest yields in a very short time. Additionally, the comparison with Aquasolv extraction provided new insights, as variations in quantified amounts of target compounds between the extracts could be explained on the basis of thermal degradation and epimerization phenomena. Especially the epimerization phenomenon for catechin/epicatechin oligomers, that is, of procyanidins P 2 and P 3, was observed for the first time. Finally, an optimized extraction and separation system was used for qualitative and quantitative investigations of compounds from different green tea samples from Ceylon (cultivated under biologically controlled conditions), Japan, India, and China as well as from one black tea sample from India.  相似文献   
68.
Low-use efficiency of phosphatic fertilizers in calcareous soils is a serious issue worldwide resulting in sub-optimal phosphorus (P) availability to plants. Polymer-coated fertilizers provide an effective solution to enhance P-use efficiency in such soils by reducing fixation and ensuring slow and consistent phosphate supply to growing plants. The present field experiment was conducted to evaluate the effectiveness of commercial diammonium phosphate (DAP) fertilizer and coated DAP with polymer and/or glycerin to improve plant growth, grain yield, and P-use efficiency of wheat crops. The results revealed that application of 100% recommended rate of glycerin + polymer coated DAP significantly enhanced plant height, number of fertile tillers m-2, 1000-grain weight, grain yield, and P uptake in comparison with commercial DAP fertilizer. Moreover, polymer coated DAP produced comparatively better results than glycerin coated DAP alone. The sustainable yield index, P agronomic and recovery efficiencies were also improved and recorded higher with glycerin + polymer-coated DAP fertilizer at 100% of the recommended rate. Furthermore, higher P uptake, P recovery, and agronomic efficiencies in response to coated DAP were found responsible for sustainable wheat yield. Overall, the glycerin + polymer-coated DAP with 75% recommended rate showed statistically identical results to uncoated DAP with 100% recommended rate. The amount of applied P vulnerable to fixation was significantly reduced with the application of glycerin + polymer-coated DAP thereby resulting in improved plant growth, grain yield, and P-use efficiency of wheat crops.  相似文献   
69.
Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas, Khadimnagar National Park (KNP) and Rema-Kalenga Wildlife Sanctu- ary (RKWS), of northeastern Bangladesh,. Status of invasive plants were investigated in 60 sample plots with 5 different habitat types, including forest, roadside, homestead, fallow land and others (ponds, canals, water logged areas, agricultural land, etc.). Data about the usage of invasive plants in traditional health care were collected through interviewing 110 households. Among the five habitat types, fallow land (28 species) pos- sessed the highest number of species, followed by roadside (25 species), forest (23 species), homestead (22 species) and others (13 species). Based on the survey, invasive plants of study areas were also categorized into five degrees of invasiveness e.g., naturalized, introduced, possibly invasive, moderately invasive and highly invasive. Additionally, there is the linear trend between degrees of invasiveness and use percentage of invasive plants. Total 39 species of invasive plants belonging to 29 fami- lies were recorded, which are generally used to treat 37 diseases, ranging from simple headache to highly complicated eye and heart diseases. The majority of the species used by the local inhabitants were herbs (16 spe- cies), followed by some shrubs (11 species), climbers (5 species), trees (5 species) and grasses (2 species). The use percentage of aboveground plant parts were higher (70.58%) than that of underground plant parts (16.18%).  相似文献   
70.
Oxidative damage is an established outcome of chronic stress. Thus, the present study was designed to investigate the modulatory role of ethanolic extract of Evolvulus alsinoides (EA) in terms of oxidative alterations at peripheral and central level in rats subjected to chronic unpredictable stress (CUS). CUS exposure for 7 days reduced Cu, Zn superoxide dismutase and catalase activity with increase in glutathione peroxidase activity and lipid peroxidation, while decrease in reduced glutathione level in blood plasma, frontal cortex and hippocampus regions of brain. Oral administration of EA extract at 200 mg/kg p.o. normalized these stress induced oxidative alterations with an efficacy similar to that of melatonin. Further, EA extract was taken up for detailed chemical investigation. Two new flavonol-4′-glycoside, kaempferol 4′-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (3) and kaempferol 4′-O-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside (5) were isolated, along with eight known compounds (1, 2, 4 and 610). The structures of new compounds were established by detailed spectroscopic studies, while known compounds were characterized by direct comparison of their reported NMR data. All these compounds were evaluated for their in vitro antioxidant activity. Compounds 3, 5, 9 and 10 at 100 and 200 μg/ml showed significant in vitro antioxidant activity. Therefore, EA may hold great potential in preventing clinical deterioration in stress induced oxidative load and related disorders.  相似文献   
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