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11.
An increasing incidence of deaths due to tuberculosis and the known drawbacks of the current existing drugs including the emergence of multi drug-resistant strains have led to a renewed interest in the discovery of new anti-tubercular agents with novel modes of actions. The recent researches focused on natural products have shown a useful way to obtain a potentially rich source of drug candidates, where alkaloids have been found more effective. The present review focuses on current epidemiology of tuberculosis, synergy of the disease with HIV, current therapy, available molecular targets and, highlights why natural products especially alkaloids are so important. The review summarizes alkaloids found active against mycobacteria from the mid-1980s to late 2008 with special attention on the study of structure–activity relationship (SAR).  相似文献   
12.
Salinity is one of the major abiotic stresses which impose constraints to plant growth and production. Rice (Oryza sativa L.) is one of the most important stapl...  相似文献   
13.
In the recent past, biochar and crop residues have attracted lots of attention as a viable strategy for maintaining soil health. This paper evaluates the comparative effect of two different doses (equivalent to 2 and 5 t C ha?1) of each of pine needle and Lantana biochar (PBC and LBC), wheat residue and lentil residue (WR and LR) on soil biological properties, nutrient availability and yield of rice and wheat in pot culture. Energy-dispersive X-ray spectroscopy (EDS) revealed higher C content of biochar than crop residues. Evaluation of biochemical quality reflected high recalcitrance indices of C and N for both PBC and LBC. Application of LBC and PBC increased the wheat grain yield significantly by 6.2%–24.2% over control. Both PBC and LBC significantly increased N and P uptakes in grain over the control and crop residues. Both biochars recorded a significant decrease of 33.9 and 71,7% in β-glucosidase activity in comparison to control at termination of study. PBC and LBC also resulted in more soil available N, P and K in soil at different intervals. The geometric mean of enzyme activities (GMea) reflected improved soil quality by PBC and LR and reduction by LBC application.  相似文献   
14.
Cystic ehinococcosis (CE) caused by Echinococcus granulosus remains a neglected zoonotic disease despite its considerable human and animal health concerns. This is the first systematic analysis of the livestock and human related economic losses due to cystic echinococcosis in India.  相似文献   
15.
Toxocara vitulorum infection in large ruminants is endemic in many tropical countries and particularly in South-East Asia. A single treatment of calves with pyrantel at 14–21 days of age effectively controls the parasite. Despite this treatment being readily available, T. vitulorum infection remains common and widespread. To understand drivers of effective control of T. vitulorum infection, we examined treatment practices and knowledge of smallholder farmers of this parasite plus determined annual calf morbidity and mortality and identified potential risk factors for these estimates. Interviews were conducted with 273 smallholder farmers who had calves tested for T. vitulorum 4–6 months earlier. Reproductive rates of 0.6 and 0.4 calf per annum in cattle and buffalo respectively, and annual calf morbidity and mortality of 42.6% (CI 0.38–0.47) and 37.3% (CI 0.33–0.42) respectively, were identified. Interviewed farmers had either none (80.6%) or only minimal (19.4%) knowledge about T. vitulorum and only 2.5% of the farmers treated their calves for T. vitulorum using the recommended control regime. Multivariable logistic regression analyses with random effects showed that the number of adult cattle per household, T. vitulorum infection status of the household herd and farmer knowledge of T. vitulorum were significantly associated with calf morbidity and mortality. Financial analysis using partial budgeting showed a net benefit of USD 3.69, 7.46, 11.09 or 14.86 per calf when treating calves with pyrantel and attributing 25%, 50%, 75% or 100% of morbidity and mortality to T. vitulorum infection. The study identified that poor reproduction, high calf morbidity and mortality combined with very limited farmer knowledge and effective control of endemic Toxocariasis, contribute to suboptimal large ruminant production in mixed smallholder farming systems in South-East Asia. The large net benefit per calf achievable by a single pyrantel treatment should drive implementation of this intervention by smallholder farmers, especially as demand for livestock products continues to increase in this region and forces a change to more production oriented farming. To support this, continued capacity building that ensures knowledge transfer of best practice T. vitulorum control to smallholder farmers is required.  相似文献   
16.
Australia experienced its first ever outbreak of equine influenza in August 2007. Horses on 9359 premises were infected over a period of 5 months before the disease was successfully eradicated through the combination of horse movement controls, on-farm biosecurity and vaccination. In a previous premises-level case-control study of the 2007 equine influenza outbreak in Australia, the protective effect of several variables representing on-farm biosecurity practices were identified. Separately, factors associated with horse managers’ perceptions of the effectiveness of biosecurity measures have been identified.  相似文献   
17.
Different combinations of slope (0.5, 5 and 10%), slope length (5.12, 7.0, 8.5, 10.75 and 14.5 m) and catchment size (0, 31.5, 54, 72, 99 and 144 m2) aimed at generating runoff supplement of 200–400 mm per tree were studied with respect to yield of runoff, soil moisture storage and fruit yield of jujube (Zizyphus mauritiana Lam.) under hot arid conditions. The runoff and soil moisture storage increased with the slope and decreased with the slope length. Similar trends were observed with regard to the fruit yield. Catchment/planted area ratios of 2:1, 1.5:1 and 0.87:1, respectively, are recommended for higher yields of jujube on slopes of 0.5, 5 and 10% with slope lengths of 8.5, 7.0 and 5.12 m.  相似文献   
18.
The oleo-gum resin of Commiphora wightii (Arn.) Bhandari, a pharmacologically important balsamiferous woody shrub, has been used in treating various ailments and disorders since ancient times (2000 B.C.) due to the presence of steroidal compound guggulsterone. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering and anti-cancerous activities. Further, guggul has been approved as food supplement by US-FDA as well as Council of Europe. Indiscriminate harvest of C. wightii from wild with negligible conservation efforts has lead to its inclusion in IUCN assemblage of endangered plant species. For identification of high guggulsterone yielding ecotypes of C. wightii, using high-performance thin-layer chromatographic (HPTLC) analysis, stem samples were collected from 50 plants from eleven locations in arid tracts of Haryana, Gujarat and Rajasthan. Dried, powdered material was subjected to extraction with petroleum ether using soxhlet apparatus. Samples were spotted on precoated activated silica plates (60F-254) and were developed using toluene–acetone (9:1 v/v) as mobile phase. The analysis was carried out in the absorbance mode at 250 nm using HPTLC scanner. The regression analysis data for the calibration plots for E and Z guggulsterone showed good linear relationship with R2 = 1 and 0.9897, respectively. Highest concentration of guggulsterone E (284 μg/g dry wt) was found in the accession collected from Palana, Bikaner whereas highest guggulsterone Z concentration (89.5 μg/g dry wt) was found in the accession collected from CAZRI, Jodhpur.  相似文献   
19.
A field experiment entitled “nitrogen and vermicompost interaction on soil and leaf nutrient status of kinnow mandarin in vertisols of Jhalawar district” was conducted at the Fruit Research Farm, Department of Fruit Science, College of Horticulture and Forestry, Jhalawar (Rajasthan) during 2012–13 to study the effect of different levels of nitrogen and vermicompost on physico-chemical properties of soil and leaf micro and macro nutrient contents of Kinnow mandarin. The result indicated that application of T15 treatment i.e. nitrogen at 350 g/plant + vermicompost 20 kg/plant was found best with regard to improvement in soil physico-chemical properties like organic carbon content (0.44%), available nitrogen (N) (379.36 kgha?1), available phosphorus (P) (25.56 kgha?1), available potassium (393.29 kgha?1) and reduces electrical conductivity (0.34 dSm?1), soil pH (7.42) and calcium carbonate (CaCO3) content percentage (15.20) of soil.  相似文献   
20.
Long-term effects of chemical fertilizers and farmyard manure (FYM) in rice (Oryza sativa)–wheat (Triticum aestivum) cropping system were monitored for two consecutive years after 38 and 39 years on productivity and soil biological properties of Mollisols. The study encompasses varying chemical fertilizer levels of optimum fertilizer rate (120, 26 and 37 kg ha?1 N, P and K, respectively) for both the crops. The treatments were application of 50% NPK, 100% NPK, 150% NPK, 100% NPK + hand weeding (HW), 100% NPK + Zn, 100% NP, 100% N, 100% NPK + 15 t FYM ha?1, 100% NPK(-S) and unfertilized control. The rice and wheat yields were highest with 100% NPK + 15 t FYM ha?1. This treatment also gave maximum and significantly more counts of bacteria, fungi and actinomycetes in soil than all the other treatments after crop harvest. The soil microbial biomass C (410.0 and 407.5 µg g?1) and N (44.53 and 48.30 µg g?1) after rice and wheat, respectively, were highest with 100% NPK + 15 t FYM ha?1, which were significantly higher over all the other treatments. The activities of soil enzymes like dehydrogenase, acid and alkaline phosphatase, arylsulphatase and urease and CO2 evolution rate with 100% NPK + 15 t FYM ha?1 were also found significantly higher over the other treatments. Fertilizer treatments with 100% NPK and 150% NPK were comparable and significantly better than application of 50% NPK, 100% N, 100% NP and 100% NPK(-S) in various studied soil biological properties. Integrated use of 100% NPK with FYM sustained the higher yields and soil biological properties under ricewheat cropping system in Mollisols. Application of Zn and hand weeding with 100% NPK were found better over 100% NPK alone in rice and wheat productivity. Imbalanced use of chemical fertilizers had the harmful effect on soil biological health.  相似文献   
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