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71.
72.

Background

Previous studies have reported that the design of the water dispensers can influence the water intake in farm animals. Horses and dairy cows seem to prefer to drink from an open surface whereas sheep and pigs apparently prefer water nipples, probably because of the worse water quality in water bowls. The aim of the present study was to examine the preference of dairy goats for water nipples or water bowls.

Methods

In each of the two experiments (exp. 1, dry goats, exp. 2 lactating goats), 42 dairy goats were allotted into 6 groups of 7 goats. In period 1, the goats had access to a water nipple. In period 2, they had access to a water bowl and in period 3 (preference test) they had access to both a water nipple and a water bowl. Water usage and wastage was recorded and water intake (water usage - water wastage) was calculated for each group for the two last days of each period. In experiment 2, water samples from each dispenser were analyzed for heterotrophy germs at 22°C, Escherichia coli and turbidity.

Results

Water usage was higher from water nipples than from water bowls both in experiment 1 (dry goats) and experiment 2 (lactating goats). There was however, no difference in water intake from water nipples and water bowls. In the preference test (period 3), the water intake tended to be higher from the water nipple than from the water bowl both for the dry goats (exp. 1) and lactating goats (exp. 2). Especially for the dry goats, the differences between groups were large. Turbidity and heterotrophy germs were much higher in the samples from the water bowls than from the water nipples.Water wastage from the water bowls was negligible compared to the water nipples. From the water nipples the water wastage was 30% and 23% of water usage for the dry and lactating goats respectively.

Conclusions

We conclude that type of water dispenser (nipple or bowl) was probably of minor importance for water intake in goats, but water bowls had a lower water quality.  相似文献   
73.
Wolffish (Anarhichos lupus) larvae were first fed in a low water-level raceway system, with two new types of formulated dry feed diets. Water level in the rearing tank was 1.5 cm. The fish showed a high preference for feeding from the surface. During the first week the fish experienced a drop in dry weights. The highest SGR of 5.8% was obtained between day 35–60. The best feeding regime gave a survival rate of 82 (2.5)%. Results indicate failure to initiate feeding as a main cause of mortality in the fed groups. Death by starvation occurred after 30–40 days. It is speculated whether the large difference in growth rates between the two feeding regimens is due to differences in carbohydrate levels between the two feed types. The rearing tank technology proved, with minor adjustments, to be self-cleaning and well suited for first feeding of wolffish.  相似文献   
74.
Adenovirus infections in immunocompromised patients are associated with high mortality rates. Currently, there are no effective anti-adenoviral therapies available. It is well known that actinobacteria can produce secondary metabolites that are attractive in drug discovery due to their structural diversity and their evolved interaction with biomolecules. Here, we have established an extract library derived from actinobacteria isolated from Vestfjorden, Norway, and performed a screening campaign to discover anti-adenoviral compounds. One extract with anti-adenoviral activity was found to contain a diastereomeric 1:1 mixture of the butenolide secondary alcohols 1a and 1b. By further cultivation and analysis, we could isolate 1a and 1b in different diastereomeric ratio. In addition, three more anti-adenoviral butenolides 2, 3 and 4 with differences in their side-chains were isolated. In this study, the anti-adenoviral activity of these compounds was characterized and substantial differences in the cytotoxic potential between the butenolide analogs were observed. The most potent butenolide analog 3 displayed an EC50 value of 91 μM and no prominent cytotoxicity at 2 mM. Furthermore, we propose a biosynthetic pathway for these compounds based on their relative time of appearance and structure.  相似文献   
75.
Long-chain (C20–24) polyunsaturated fatty acids (LC-PUFAs) are essential nutrients that are mostly produced in marine ecosystems. Previous studies suggested that gammarids have some capacity to endogenously produce LC-PUFAs. This study aimed to investigate the repertoire and functions of elongation of very long-chain fatty acid (Elovl) proteins in gammarids. Our results show that gammarids have, at least, three distinct elovl genes with putative roles in LC-PUFA biosynthesis. Phylogenetics allowed us to classify two elongases as Elovl4 and Elovl6, as they were bona fide orthologues of vertebrate Elovl4 and Elovl6. Moreover, a third elongase was named as “Elovl1/7-like” since it grouped closely to the Elovl1 and Elovl7 found in vertebrates. Molecular analysis of the deduced protein sequences indicated that the gammarid Elovl4 and Elovl1/7-like were indeed polyunsaturated fatty acid (PUFA) elongases, whereas Elovl6 had molecular features typically found in non-PUFA elongases. This was partly confirmed in the functional assays performed on the marine gammarid Echinogammarus marinus Elovl, which showed that both Elovl4 and Elovl1/7-like elongated PUFA substrates ranging from C18 to C22. E. marinus Elovl6 was only able to elongate C18 PUFA substrates, suggesting that this enzyme does not play major roles in the LC-PUFA biosynthesis of gammarids.  相似文献   
76.
Pyometra (uterine inflammation with accumulation of pus in the uterus) is regarded as one of the most common illnesses in bitches. The ethiology and pathogenesis are complex with both hormonal and bacterial elements. The bacteria most frequently isolated from the uterine content is Escherichia coli.In this study, 84 E. coli strains from the uteri of 70 bitches suffering from the disease were examined and their DNA-profiles compared by restriction enzyme analysis and pulsed-field gel electrophoresis (PFGE). Through variations in DNA-profiles of the E. coli isolates, this study indicates that pyometra is caused by E. coli originating from the normal flora of the dogs and not by certain clones spread between animals.E. coli strains from the urinary bladder and the uterus of six of the bitches suffering from simultaneous urinary tract infection and pyometra were examined and compared as above. The DNA-profiles of the isolates from each of the six bitches were 100% identical. This study supports the theory suggesting that in cases of simultaneous urinary tract infection and E. coli pyometra, the urinary tract and uterus are infected with the same bacterial strain.To evaluate whether the uterus was infected with a single clone of E. coli or if multiple clones were present, eight to 16 colonies of E. coli isolated from pyometra samples from a further 10 bitches were examined. All bacterial colonies from the culture of the same bitch showed identical DNA-profiles.In 14 of the 70 bitches, two macroscopically different but biochemically identical E. coli colony types were isolated. The two colony types from the same bitch proved to have identical DNA-profiles in 13 cases and almost identical in the remaining bitch.  相似文献   
77.
The effects of different planting densities (250,000, 500,000 and 750,000 plants ha−1) and cutting frequencies (45, 60 and 75 days) on the biomass production and chemical composition of Moringa oleifera was studied in a completely randomised split plot design with four blocks, in Managua, Nicaragua, located geographically at 12°08′15′′ N and 86°09′36′′ E. The 75 day cutting frequency produced the highest fresh matter yield, 100.7 and 57.4 Mg ha−1 year−1, and dry matter (DM) yield, 24.7 and 10.4 Mg ha−1 year−1, during the first and second year, respectively. All planting densities produced the highest DM yield at 75 day cutting frequency. In the first year, the density of 750,000 plants ha−1 produced the highest fresh matter yield, 88.0 Mg ha−1 and highest DM yield, 18.9 Mg ha−1, but in the second year the density of 500,000 plants ha−1 gave the highest yields, 46.2 Mg ha−1 and 8.1 Mg ha−1, respectively. During the first year, DM (22.8%), neutral detergent fibre (NDF) (30.8%) and ash (9.14%) contents were highest and in vitro DM digestibility (IVDMD) (68.2%) was lowest in the longest cutting interval, while contents of crude protein (CP) (22.8%) and acid detergent fibre (ADF) (22.8%) were not affected significantly by cutting frequency. In the second year, DM and CP contents and IVDMD were not significantly affected by cutting frequency, whereas NDF, ADF and ash contents were lowest in the 60 day cutting frequency. Planting density had no significant effect on chemical composition or IVDMD. These data suggest that Moringa forage could be an interesting protein supplement for ruminants.  相似文献   
78.
In order to evaluate pea lectin as a resistance factor against the pollen beetle (Meligethes aeneus), transgenic oilseed rape (Brassica napus) has been produced wherein the pea lectin gene expression is driven by a pollen-specific promoter. The aim of the present study was to identify and characterise non-segregating transgenic and non-transgenic lines to be compared in various future tests for benefits and risks associated with such transgenic crop plants. Three doubled haploid (DH) populations (1436, 1440 and 1451) expected to include lectin-producing lines and two DH populations (1443 and 1449) expected to be free of lectin were produced. All five populations originated from different transformation events in the cultivar Westar. The relative amounts of DNA from the marker gene cassette were quantified by conventional as well as real-time PCR analyses and lectin concentrations were estimated by western blot analysis. Two populations with high lectin concentrations, 1436 and 1451, contained higher amounts of the marker DNA and thus more lectin gene copies as compared with 1440 which had lower concentrations of the lectin. As expected all DH lines from 1443 and 1449 were free of lectin. Maximum pea lectin concentration obtained corresponded to 3% of total soluble protein in the anthers. There were significant differences between the populations with respect to bud and flowering stage phenology as well as seed yields, but the differences were not related to their transgenic status. All in all there were 171 lines tested for phenology and transgenic status, out of which 89 with similar phenology were subjected to tests for lectin concentration and seed yield, and 20 of these lines were retested in the next generation. Finally two lines with high lectin concentrations and one with an intermediate level along with two matching non-transgenic lines were selected for future benefit/risk experiments.  相似文献   
79.
80.
The chemical composition, digestibility, and voluntary feed intake by sheep of mango by-products were studied in an experiment with five dietary treatments consisting of mango peels and seed kernels, offered individually or together with urea block and a control. The mango residues were offered with rice straw and the control diet was straw only. Five groups of five male sheep of Djallonké type, 12–18 months old and weighing on average 18.6 kg were allocated randomly to the diets to assess the voluntary feed intake. Apparent digestibility of the same diets was measured using four sheep per diet. The mango residues were low in crude protein, 67 and 70 g/kg dry matter for the peels and the seed kernels, respectively. The content of neutral detergent fiber varied from 306 to 388 g/kg dry matter (DM) for the kernel and the peels, respectively. The kernel had relatively high level of fat (105 g/kg DM) and tannins (29 and 40 g/kg DM of hydrolysable and total tannins, respectively). The highest intake was observed with the diet containing both residues and urea block (741 g/day). The intake of kernels was lower in all diets when offered with the peels than when offered with rice straw alone. Apparent digestibility of the diets containing mango residues was 0.60–0.65. The peels and kernels had high digestibility coefficients (0.74 and 0.70, respectively). Based on the results above, it can be concluded that it would be interesting to test the residues in a growth experiment.  相似文献   
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