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11.
Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.  相似文献   
12.
Recent advances in methodology and instrumentation have made possible the detection and determination of pesticides at microgram kg-1 (ppb) levels. The sensitivity of a method of analysis depends greatly on the efficient extraction of the pesticide and the subsequent clean-up of the extract. The extract from green tea leaves is a mixture of aroma components, polyphenols and caffeine. The preparation of made tea from green tea leaves adds to this complexity by concentrating these coextractives. Conventional clean-up techniques provide poor recoveries for parathion-methyl and chlorpyrifos from both green tea leaves and made tea. This arises from interference by caffeine during gas chromatography, as it has a similar retention time to the two pesticides and peaks overlap. A modification to the protocol based on a solvent partitioning process using dichloromethane and subsequent washing of the extracts with warm water removed the caffeine, and pigments were removed by column chromatography. Recoveries ranging from 80 to 90% were then obtained for both pesticides.  相似文献   
13.
The objective of the present study was to investigate the curative and antioxidative efficacy of ivermectin and ivermectin + vitamin E-selenium, and the influence of these agents on oxidative stress parameters in canines infested by Sarcoptes scabiei. Twenty two sarcoptic mites infested dogs and nine healthy dogs of 6 months to 2 years of age were divided into three groups. Group I comprised of healthy dogs (n = 9) whereas animals in group II (n = 11) and III (n = 11) were positive for scabies. Group II animals were treated with only 1% ivermectin @ 0.2 mg/kg SC whereas group III were additionally treated with Vitamin E and selenium (tocopherol 50 mg + Se 1.5 mg/ml) @0.5 ml/20 kg IM at weekly intervals for three times. Blood samples were collected on day 0 and 28 post therapy. The values for hemato-biochemical parameters and activities of antioxidant enzymes were significantly decreased (P < 0.05) whereas level of lipid peroxidation was significantly increased in all the infested dogs in comparison to the healthy dogs on day 0 which approached normalcy by day 28 post therapy. The dogs of group III showed better clinical recovery in comparison to group II at the end of therapy. Thus, administration of vitamin E and selenium in addition to standard therapy can alleviate these alterations hastening the clinical recovery of diseased dogs and can be recommended as an adjunct therapy with miticides for canine sarcoptic mange.  相似文献   
14.
A case report on XO/XX/XXX mixoploidy in a goat   总被引:1,自引:0,他引:1  
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15.
16.
An experiment was conducted by planting Hardwickia binata Roxb. at 200, 400 and 800 trees ha???1, intercrops viz., Brassica campestris (mustard) and Glycine max (soybean) were sown from the second year onwards in winter and summer respectively at the National Research Centre for Agroforestry, Jhansi, U.P., India with the objectives of evaluating agrosilvicultural potential of the system and to study the effect of tree densities on ecophysiology of understorey crops. Tree growth was affected by both density and intercrop in the initial years of growth. Photosynthetic photon flux density (PPFD) available to the intercrops reduced with increasing densities. Transpiration rate and stomatal conductance in intercrops decreased due to the presence of trees. No significant changes in leaf temperature were observed till the fifth year of the growing season. Yield was significantly higher in pure crop in comparison with all the densities in mustard. Soybean yield under 200 trees ha???1 was comparable to that of the pure crop. Trees at the density of 200 trees ha???1 provided a conducive microenvironment to the intercrops.  相似文献   
17.
Seed priming is a commercially applied technique for improving seed vigor under variable field conditions. The present study was carried out to optimize the methods (direct: soaking in water 1:1 W/V and indirect: preconditioning under high RH ≥ 85%) and duration (hours)of hydro-priming, attempting to correlate the critical seed water content with priming-induced metabolic-restart in dry mungbean (Vigna radiata L.)seeds. Although the rate of water absorption and the amount of water absorbed was more by direct compared to the indirect imbibition method, the priming-induced germination responses were identical after 6hof priming treatment. The seed water content absorbed during this period was crucial for initiating the chain of biochemical events, required for early synchronized germination in primed seeds which was evident by improved membrane permeability, high activity of catalase and superoxide dismutase, and more integrated chloroplast and mitochondria in primed seeds. We demonstrate that the critical water content, required for priming-induced benefits for germination vigor, is a relative unit with respect to the duration of priming and the rate of water absorption. Seed priming is a co-ordinately regulated mechanism for controlling germination capacity of seeds by modifying the permeability characteristics of biological membranes and enzyme activity. This study helps to enhance our understanding on the potential of seed priming for synchronized germination and early seedling establishment in the field and beneficial for the resource poor farming community for better return of their limited financial/farm resources under variable environmental/field conditions.  相似文献   
18.
Mahonia napaulensis DC. (local name—Taming) family Berberidaceae, produces natural dye from its stem which has been used for dyeing textiles by the Apatanis (a tribe of Arunachal Pradesh) since ancient times. Sonicator dyeing with Mahonia napaulensis showed marked improvement in dye uptake. It showed that pretreatment with metal mordant (2%, w/w with respect to the fabric) improved substantially the fastness properties for dyed cotton, silk fabrics and wool yarn. Five fractions were isolated from column chromatography of the stem extract of Mahonia. Attempts have been made to identify these fractions by matching the spectral data which indicated that they were from a well-known isoquinoline alkaloid family.  相似文献   
19.

Background

Cutin is a complex, highly cross-linked polyester consisting of hydroxylated and epoxidated acyl lipid monomers. Because of the complexity of the polymer it has been difficult to define the chemical architecture of the polymer, which has further limited the ability to identify the catalytic components that assemble the polymer. Analogous to methods that define the structure of oligosaccharides, we demonstrate a strategy that utilizes cutinase to generate cutin subfragments consisting of up to four monomeric units, whose structure and spatial distribution in the polymer is revealed by high-resolution mass spectrometry. Moreover, the application of mass-spectrometric fragmentation and labelling of the end of the oligomers, one is able to define the order of monomers in the oligomer. The systematic application of this strategy can greatly facilitate understanding the chemical architecture of this complex polymer.

Results

The chemical architecture of plant cutin is dissected by coupling an enzymatic system that deconstructs the polymer into subfragments consisting of dimers, trimers and tetramers of cutin monomers, with group-specific labeling and mass spectrometry. These subfragments can be generated with one of over 1200 of cutinases identified from diverse biological sources. The parallel chemical labeling of the polymer with dansyl, alkyl or p-dimethylaminophenacyl reagents can identify the chemical distribution of non-esterified hydroxyl- and carboxyl-groups among the monomers. This combined strategy is applied to cutin isolated from with apple fruit skins, and a combination of gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–quadrupole time-of-flight (Q-TOF) MS is used to determine the order of the monomers in the cutinase-generated subfragments. Finally, we demonstrate the use of matrix-assisted laser desorption-ionization-MS to determine the spatial distribution of the cutinase-generated subfragments.

Conclusion

Our experimental results demonstrate an advancement to overcome the current limitations in identifying cutin oligomeric structure and allows one to more efficiently address new biological questions about cutin biosynthesis. We submit that the systematic application of these methods will enable the construction of more accurate architectural models of cutin, which is a prerequisite to identifying cutin-biosynthetic components.
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20.
Summary Some members of the family Amaranthaceae, which has mostly been reported as non-mycorrhizal, were examined for a symbiotic association with mycorrhizae in the semiarid and arid zones. Ten species belonging to five genera, Achyranthes, Aerva, Alternanthera, Amaranthus, and Celosia were examined, using 1.0-cm long root standards. Intercellular hyphae, vesicles and arbuscules were observed in the root cortex. The number of different types of spores in the rhizosphere soil of different plants ranged from one to three. The spores isolated represented nine species belonging to four genera, Glomus, Gigaspora, Sclerocystis, and Scutellospora. No correlation could be established between spore counts and either soil pH or soil moisture.  相似文献   
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