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81.
A spectrophotometric method has been developed for the determination of ziram (zinc bis(dimethyldithiocarbamate)) and zineb (zinc ethylenebisdithiocarbarnate) by converting these into a zinc-4-(2-pyridylazo)resorcinol complex, which is dissolved in acetone and water and the absorbance measured at 490 nm against a reagent blank. Beer's law is obeyed over the concentration ranges 0.025-1.25 and 0.025-1.5 mg litre?1 for ziram and zineb respectively in the final solution. The method is sensitive and can be used for the direct determination of ziram and zineb in commercial formulations, grains (rice and wheat) and synthetic mixtures (in the presence of various other dithiocarbamates). The limit of determination of ziram and zineb from foodstuffs in 0.2 mg kg ?1.  相似文献   
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The tuberous roots of Decalepis hamiltonii are consumed as pickles and beverages and are believed to possess health-promoting properties. We have investigated the antioxidant potential of the roots. The methanolic extract of the root showed a high antioxidant activity. The methanolic extract was fractionated on a silica gel column, which showed three major fractions with good antioxidant activity. The active fractions were further subjected to preparative thin layer and silica gel column chromatography, which yielded six pure compounds. The purified compounds were characterized by MS, 1H NMR, 13C NMR, and two-dimensional NMR spectroscopic techniques and identified as 2-hydroxy-4-methoxybenzaldehyde, p-anisaldehyde, vanillin, borneol, salicylaldehyde, and bis-2,3,4,6-galloyl-alpha/beta-D-glucopyranoside. The latter compound, named decalepin, is a new antioxidant molecule from the plant kingdom. The purified compounds showed antioxidant activities in in vitro assays such as inhibition of lipid peroxidation, hydroxyl radical, superoxide anion, and 1,1-diphenyl-2picrylhydrazyl radical scavenging. This is the first report of the antioxidant constituents of the roots of Decalepis hamiltonii.  相似文献   
85.
Regeneration has been achieved in blackgram (Vigna mungo) using thidiazuron (TDZ) in the culture medium. The explanted cotyledon with wounded embryonic axes produced the highest number (9.75–10.45) of healthy, elongated shoots when cultured on shoot bud regeneration medium (SRI) composed of 2 μM BAP, 2 μM KIN, 2 μM TDZ, and 0.5 μM NAA followed by multiple shoot regeneration (SRII) medium containing 2 μM BAP, 2 μM KIN, and multiple shoot elongation (SE) medium (0.5 μM of BAP + 0.5 μM of KIN). The presence of TDZ in combination with BAP and NAA in the SRI medium for one sub-culture cycle (10–14 days) significantly increases formation of multiple shoot buds per explant. Independent, healthy shoots obtained were selected for both in vitro rooting and grafting. Establishment of plantlets in the soil was highest (80–100%) in the case of in vitro rooted compared to grafted shoots (40%). The protocol appears to be competent to Agrobacterium-meditated transformation with ‘gus’ as a reporter gene. PCR analysis of the T0 and T1 progenies showed the presence and transmission of the transgene. We document here the regeneration and transformation of blackgram using cotyledons with wounded embryonic axes and the protocol appears to be suitable for genetic transformation of blackgram.  相似文献   
86.
Objective-To compare associations between vaccine types and other injectable drugs with development of injection-site sarcomas in cats. Design-Case-control study. Animals-181 cats with soft tissue sarcomas (cases), 96 cats with tumors at non-vaccine regions (control group I), and 159 cats with basal cell tumors (control group II). Procedures-Subjects were prospectively obtained from a large pathology database. Demographic, sarcoma location, basal cell tumor, and vaccine and other injectable history data were documented by use of a questionnaire and used to define case, control, and exposure status. Three control groups were included: cats with sarcomas at non-vaccine sites, cats with basal cell tumors, and a combined group of cats with sarcomas at non-vaccine sites and cats with basal cell tumors. χ(2) tests, marginal homogeneity tests, and exact logistic regression were performed. Results-In the broad interscapular region, the frequency of administration of long-acting corticosteroid injections (dexamethasone, methylprednisolone, and triamcinolone) was significantly higher in cases than in controls. In the broad rear limb region, case cats were significantly less likely to have received recombinant vaccines than inactivated vaccines; ORs from logistic regression analyses equaled 0.1, with 95% confidence intervals ranging from 0 to 0.4 and 0 to 0.7, depending on control group and time period of exposure used. Conclusions and Clinical Relevance-This case-control study measuring temporal and spatial exposures efficiently detected associations between administrations of various types of vaccines (recombinant vs inactivated rabies) and other injectable products (ie, long-acting corticosteroids) with sarcoma development without the need to directly measure incidence. These findings nevertheless also indicated that no vaccines were risk free. The study is informative in allowing practitioners to weigh the relative merits and risks of commonly used pharmaceutical products.  相似文献   
87.
Universally, trees have been recognized as an important component of urban landscapes for millennia because they provide a wide range of benefits to society. Although the planting of trees has been an integral and important part of human settlements in Nepal, the concept of urban forestry is poorly understood and often neglected. This paper investigates urban peoples?? perceptions towards urban forests as well as the perceived benefits related to the use and existence of urban forests in Lalitpur, Nepal. A survey was conducted among residents and visitors to an urban park. Most respondents held positive attitudes towards urban forests and were aware of the benefits provided. Despite involvement of various agents from both government and non-governmental organizations in promoting urban forests, greenery was declining in the city. The loss and degradation of urban forests adversely affected the ecosystems because the city is suffering from water, air and soil pollution. In recent years, the local government has promoted urban greenery; however, there are no accompanying legislation or regulations governing urban forestry. Therefore, concrete scientific and professional knowledge is required in order to manage the forestry in the city.  相似文献   
88.
Sperm cells perform precise chemotactic and thermotactic movement which is crucial for fertilization. However, the key molecules involved in detection of different chemical and physical stimuli which guide the sperm during navigation are not well understood. Ca2+-signalling mediated by ion channels seem to play important role in motility and other fertility parameters. In this work, we explored the endogenous localization pattern of TRPV channels in the mature spermatozoa of avian species. Using sperm from white pekin duck (Anas platyrhynchos) as the representative avian model, we demonstrate that duck sperm endogenously express the thermosensitive channels TRPV1, TRPV2, TRPV3, TRPV4, and highly Ca2+-selective channels TRPV5 and TRPV6 in specific yet differential locations. All of these TRPV channels are enriched in the sperm tail, indicating their relevance in sperm motility. Interestingly, the TRPV3 and TRPV4 channels are present in the mitochondrial region. Calcium selective TRPV5 channel is exclusively present in sperm tail and is most abundant among the TRPV channels. This is the first report describing the endogenous presence of TRPV2 and TRPV3 channels in the sperm of any species. Using confocal imaging and super-resolution imaging, we demonstrate that though the TRPV channels are evolutionarily closely related, they have distinct localization pattern in the duck sperm, which could impact their role in fertilization.  相似文献   
89.
A pot experiment was conducted to evaluate different arbuscular mycorrhiza sps. (AM) for their effect on plant growth, yield and nutrient uptake by wheat. All the AM fungal sps. significantly enhanced all the plant parameters and nutrient uptake by the plant. A positive correlation was observed between percent root colonization by AM fungi and most of the plant parameters studied. Glomus macrocarpum giving best results was selected for studying interactive effect with Azotobacter, Azospirillum (well-known PGPRs), and Flavobacterium and Proteus vulgaris (less studied PGPRs). All the PGPRs significantly increased most of the plant parameters studied and their combination with AMF had a synergistic effect. Amongst PGPRs, Flavobacterium gave best response both singly and in combination with AMF and thus, is a potential new bioinoculant for wheat. Application of 120 kg nitrogen (N) ha?1was the best treatment. Inoculation with most of the PGPRs gave better response than 60 kg N ha?1.  相似文献   
90.
The impact of fiber friction, yarn twist, and splicing air pressure on mechanical and structural properties of spliced portion have been reported in the present paper. The mechanical properties include the tensile and bending related properties and, in the structural properties, the diameter and packing density of the splices are studied. A three variable three level factorial design approach proposed by Box and Behnken has been used to design the experiment. The results indicate that there is a strong correlation between retained spliced strength (RSS) and retained splice elongation (RSE) with all the experimental variables. It has been observed that RSS increases with the increase in splice air pressure and after certain level it drops, whereas it consistently increases with the increase in yarn twist. The RSE increases with the increase in both fiber friction and yarn twist. It has also been observed that the yarn twist and splicing air pressure have significant influence on splice diameter, percent increase in diameter and retained packing coefficient, but the fiber friction has negligible influence on these parameters. Yarn twist and splicing air pressure has a strong correlation with splice flexural rigidity, where as poor correlation with retained flexural rigidity.  相似文献   
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