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51.
The historical changes in European Black Pine population size across the whole natural distribution in Europe and Asia Minor were analyzed facing the Plio-Pleistocene climatic fluctuations. Thirteen chloroplast SSRs and SNPs markers have been studied under the assumptions of “neutral evolution.” Populations and meta-populations had different histories of migration routes, and they were strongly affected by complex patterns of isolation, fragmentation, speciation, expansion (1.88–4.28 Ma), purification selection (2.09–21.41 Ma) and bottleneck (1.85–21.76 Ma). A significant number of populations (min. 29–41%) were in equilibrium for very long periods. Generally, the bottleneck revealed by chloroplast DNA is weaker than the bottleneck revealed by nuclear DNA. The N e immediately after the bottleneck reaches between 1820 and 3640 individuals. Generally, the historical effective population sizes shrink significantly for the Tertiary period from 10–15 up to 2.5 Ma in Western Europe (by 82%), followed by Asia Minor (69%) and the Balkan Peninsula (28%), likely resulting from important climatic changes. The rates and frequencies of stepwise westwards migration waves have been not sufficient to prevent isolation between the meta-populations and to suppress “sympatric speciation.” The migration was weak for the Pliocene, but was maximal for the Pleistocene, and finally silent for the present interglacial period, namely the Holocene.  相似文献   
52.
Seventeen Streptococcus equi subsp. zooepidemicus strains isolated from camels and camel milk in Kenya and Somalia were identified by their cultural characteristics, by biochemical and serological reactions with the help of commercial identification systems and by molecular studies using a multiplex PCR. The isolates were further characterized by a PCR-mediated detection of size polymorphisms in the 16S-23S rDNA intergenic spacer region and the virulence gene szp and by amplification of the virulence gene cne. These molecular analysis are potentially useful in identifying and characterizing S. equi subsp. zooepidemicus strains of this origin and could possibly be valuable in epidemiological investigations.  相似文献   
53.
A trial to assess the efficacy of eprinomectin (EPM) against the lungworm Dictyocaulus arnfieldi was carried out on 15, naturally-infected donkeys. Ten animals were treated with a ‘pour-on’ EPM preparation (at a dose of 0.5 mg/kg bodyweight), and five animals acted as controls. Faecal larval counts were carried out two days before treatment, on day of treatment and 7, 14, 21 and 28 days post-treatment with the anthelmintic. EPM was 100% effective in eliminating faecal larvae from day 7, until the end of study at day 28. No adverse drug-reactions or side-effects were observed in any of the treated donkeys.  相似文献   
54.
1. The aim of this study was to determine the effects of juniper oil (JO) dietary supplementation on the laying performance, egg traits and egg malondialdehyde (MDA) concentrations of quail.

2. A total of 400 female Pharaoh quails were equally divided into 4 groups containing 100 quails (5 replicates of 20 quails each). The study included a control treatment with no diet additives, and the treatments were as follows: (group 1) 100 mg JO/kg; (group 2) 200 mg JO/kg; (group 3) 300 mg JO/kg. The experiment was carried out for 60 d.

3. At the end of the experiment, there were no significant differences in body weight, egg weight, egg mass, egg shape index, yolk colour, egg production, feed consumption or feed efficiency.

4. The Haugh unit was increased in groups 2 and 3 compared to the control group. Dietary fortification with JO improved eggshell thickness and breaking strength compared to the control group. Furthermore, the damaged egg ratio was significantly decreased in group 3 compared to the control. The increasing concentration of JO (200 and 300 mg/kg) caused a significant decrease in egg yolk MDA concentration after 15 and 30 d of storage at 20°C.

5. It was concluded that inclusion of JO in layer diets can improve egg quality characteristics in terms of Haugh unit, eggshell thickness and breaking strength. Moreover, supplementation of JO in the diets of quail may enhance the antioxidant status of eggs, and the most effective doses of JO were 200 and 300 mg/kg.  相似文献   

55.
Mycoplasma gallisepticum is the primary agent of chronic respiratory disease causing important economic losses in the poultry industry. Serological monitoring is essential to maintain mycoplasma-free breeder flocks and often complicated by the cross-reactions between different mycoplasma species. To overcome serological cross-reactions, a large fragment of the M. gallisepticum PvpA cytadhesin, species-specific surface-exposed protein, was produced in E. coli as a recombinant protein (rPvpA336) and used as a potential diagnostic antigen. The rPvpA336 protein possesses 336 mycoplasma-specific amino acids with relative molecular weight of 44 kDa. A deletion region of 37 amino acids was identified when compared to the wild-type PvpA protein. Immunoreactivity of the rPvpA336 protein has been demonstrated by Western blot analysis with M. gallisepticum-positive and -negative chicken sera. Furthermore, an enzymatic rapid immunofiltration assay (ERIFA) prototype based on the rPvpA336 protein has been developed and its species-specific detection capability has been demonstrated by using M. gallisepticum and/or M. synoviae-positive and -negative chicken sera. In addition to its species-specificity, the ERIFA prototype presents certain advantages such as rapidity, field-applicability and cost-effectiveness. Therefore, these advantages would make the prototype a species-specific rapid diagnostic tool of choice in the field and limited laboratory conditions for screening M. gallisepticum infections.  相似文献   
56.
1. This study was to evaluate the toxic effects of aflatoxin (AF) on growth performance of quail, and to determine the preventive efficacy of MYCOTOX (oxicinol, tymol, micronised yeast). 2. One hundred and eighty 1-d-old quail (Coturnix coturnix japonica) of both sexes were weighed and randomly divided into 4 experimental groups each with 5 replicates of 9 birds. 3. There were 4 dietary treatments: (1) control with 0 mg AF/kg diet and 0% MYCOTOX; (2) 0 mg AF/kg diet and 0.5% MYCOTOX; (3) 2.5 mg AF/kg diet and 0% MYCOTOX; (4) 2.5 mg AF/kg diet plus 0.5% MYCOTOX. The chicks were maintained on these treatments to 3 weeks of age. Quail consumed the diets and water ad libitum. 4. Body weight (BW) gains in groups receiving AF alone were the lowest at all periods. Feed intake was lowest in the group consuming the AF diet. The addition of MYCOTOX to the AF diet did not prevent or reduce the toxic effects of AF on feed intake at any time period. Feeding diets containing MYCOTOX alone did not change feed intake significantly. With the exception of the 1 to 7 d period, feed conversion of chicks fed the AF diet was similar to those of the other experimental groups. 5. Bursa of Fabricius weight decreased, whereas the relative weights of liver, kidney and spleen increased in quail consuming diets containing AF and AF plus MYCOTOX. Liver colour was normal in the control and MYCOTOX alone group, but was lighter in groups fed AF. 6. The results indicated that MYCOTOX was not effective in preventing the deleterious effects of AF.  相似文献   
57.
This field study was conducted to compare conception and insemination efficiency responses to intrauterine polyvinylpyrrolidone-iodine (PVP-I) and antibiotic (AB) treatments in dairy cows that experienced pregnancy loss. Data were collected from lactation cows with a history of pregnancy loss 27 to 70 days post-insemination (n = 97) during the 1st to 3rd lactation (days in milk = 196 ± 28). Cows were subjected to 1 of 3 treatments: i) 50 mL saline solution intrauterine infusion (S; n = 23); ii) 2% PVP-I (n = 42); or iii) 150 mg of amoxicillin trihydrate and 40 mg/mL gentamicin sulphate (n = 32). All cows followed the progesterone-based fixed-time insemination protocol. Data were analyzed by Chi-square test and 1-way analysis of variance. The PVP-I treatment (n = 25; 59.5%) was as effective as the AB treatment (n = 19; 59.4%), compared to the S treatment (n = 5; 21.7%) to achieve a new conception. The cows in group PVP-I conceived in a shorter time than those in group AB (46.0 ± 8.7 days versus 105.0 ± 10.0 days; P < 0.05) with a more efficient insemination to conception ratio (2.32 ± 0.43 versus 4.10 ± 0.32; P < 0.05). Data suggest that intrauterine PVP-I administration is superior to intrauterine AB administration in rescheduling reproductive protocol upon late embryonic and fetal losses.  相似文献   
58.
The Paraíba do Sul river is located in one of the most developed part of Brazil and receives many organic and industrial effluents directly affecting the ichthyofauna. Concentration of four heavy metals (Cu, Cr, Zn and Pb) were determined in two tissues (muscle and gonads) of three abundant fish species from different trophic levels (Oligosarcus hepsetus—carnivore, Geophagus brasiliensis—omnivore and Hypostomus luetkeni—detritivore) between November 2002 and April 2003. The aim was to test the hypothesis that the trophic level and the proximity from impacted areas influence levels of contamination and to assess if these species are indicators of large-scale habitat quality. Levels of heavy metals were detected by Total Reflection X-ray Fluorescence with Synchrotron Radiation (SR-TXRF) at the Brazilian National Synchrotron Radiation Laboratory (LNLS). Generally, gonads showed higher metal concentration than muscles, except for Cr. All examined metals, but Cu, exceeded the maximum permitted concentration (mpc) by the Brazilian legislation for human consumption in at least one tissue. O. hepsetus (carnivore) showed the highest contamination levels, followed by G. brasiliensis (omnivore) and H. luetkeni (detritivore). The middle-upper segment, which encompasses large urban areas, showed the highest levels of metal contamination in most cases. O. hepsetus showed the highest levels of contamination in muscles for Pb in the middle-upper river segment (7.98?±?3.73; mpc?=?2.0 μg g?1) and for Cr in the upper (5.53?±?0.05; mpc?=?0.10 μg g?1) and middle-upper (4.20?±?0.85; mpc?=?0.10 μg g?1) segments, which indicates that human population should avoid to consume these fishes species from these segments of the Paraíba do Sul river.  相似文献   
59.
Gene flow via outcrossing from transgenic plants to relatives will be one of the most important concerns to grow of the transgenic chickpea (Cicer arietinum L.) in European Union (EU). This report is therefore focused on spontaneous outcrossing rate in chickpea. A total of 39 kabuli type mutants with white flower and one desi type with pink flower were grown to estimate spontaneous outcrossing rate. Outcrossing rate ranged from 0.0 to 1.25% in mutant materials. Since labelling threshold for transgenic contamination in food and feed in European Union (EU) is 0.9%, outcrossing rate of 1.25% is higher than threshold of 0.9% in EU, and this result suggests that cultivation of transgenic chickpea will be under high risk to be contaminated chickpeas in neighbourhood fields.  相似文献   
60.
In this study, we investigated the effect of tetraethylammoniumbromide (TEAB) salt on the spinnability of polyurethane nanofibers via roller electrospinning method. At first, solution properties, spinnability and fiber properties were determined and then all the results were analyzed. According to the results, TEAB salt concentration has an important effect on the conductivity, viscosity, spinning performance, fiber diameter and morphology. It was found that all these parameters increased with salt concentration. Also it was indicated that viscosity decreased with shear rate. Polyurethane including 1.82 wt % TEAB gives the best spinning performance although 0.87 wt % TEAB is the optimum value related to fiber properties such as diameter, uniformity and morphology given the ideal polyurethane nano web structure.  相似文献   
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