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21.
Flight patterns of migrant alate Russian wheat aphids (=RWA),Diuraphis noxia (Kurdj.) during its expansion from the south-east to Central Europe were determined. Samples were taken by Rothamsted-type suction air traps in Hungary (one location, 1990–1997) and in the Czech Republic (5 locations, 1994–1998). The results document a progressive expansion of RWA, and population variation in the individual years and periods of the season. A comparison of the evidence on RWA in the individual years since its detection in Hungary and in the Czech Republic supports the presumption on the occurrence of an expansion route from the south-east (Turkey) to Central Europe. This expansion is classified as an adventive route of the over-all expansion that has covered the whole West-Mediterranean (South Europe, North Africa). 相似文献
22.
Eva Syrová Miroslava Palíková Jan Mendel Veronika Seidlová Ivana Papežíková Heike Schmidt-Posthaus Kristina Somerlíková Hana Minářová Lukáš Mareš Ivana Mikulíková Jiří Pikula Jan Mareš 《Journal of fish diseases》2020,43(10):1201-1211
Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea) is the causative agent of proliferative kidney disease (PKD), which affects both wild and farmed salmonid fish. The objective of this study was to outline differences in susceptibility to PKD in different salmonid species, hybrids and breeding lineages. Susceptibility to T. bryosalmonae infection was established based on cumulative mortality, pathological findings and detection of T. bryosalmonae in the kidney using immunohistochemistry and molecular methods. Determination of pure and hybrid individuals of different species in the genus Salvelinus, and dissimilarity of rainbow trout lineages, was performed using traditional polymerase chain reaction (PCR) and microsatellite analyses. Rainbow trout displayed higher disease severity compared with brook trout and Alsatian charr. Moreover, the results indicated differences in infection susceptibility, not only among different salmonid species but also among different lineages of charr and rainbow trout. Our study indicated that some salmonid species and even different lineages of the same species are more suitable for farming under PKD pressure. 相似文献
23.
Hana Šubrtová Salmonová Matilde Marchi Ivo Doskočil Tereza Kodešová Eva Vlková 《Journal of fish diseases》2020,43(10):1213-1227
Pectinatella magnifica is an invasive freshwater bryozoan that has expanded in many localities worldwide, including fishing areas. It contains microbial communities, predominantly consisting of Aeromonas bacteria that are frequently associated with fish infections. The objective of this study was to investigate the potential pathogenicity of Aeromonas spp. associated with P. magnifica and evaluate the health risks for fish. Aeromonas strains were isolated from P. magnifica (101 strains) and from surrounding water (29 strains) in the South Bohemian region and investigated for the presence of 14 virulence-associated genes using PCR. We demonstrated high prevalence of phospholipase GCAT, polar flagellin, enolase, DNAse, aerolysin/cytotoxic enterotoxin, serine protease and heat-stable cytotonic enterotoxin-coding genes. Further, all twelve isolates that were analysed for cytotoxicity against intestinal epithelial cells were found to be cytotoxic. Six of the isolates were also tested as co-cultures composed of pairs. Enhanced cytotoxicity was observed when the pair was composed of strains from different species. In conclusion, P. magnifica is colonized by Aeromonas strains that have a relatively high prevalence of virulence-associated genes and the ability to provoke disease. Results also suggest a possibly increased risk arising from mixed infections. 相似文献
24.
Eliška Sudová Veronika Piačková Hana Kroupová Martin Pijáček Zdeňka Svobodová 《Fish physiology and biochemistry》2009,35(4):599-605
The aim of the study was to assess the effects of the anthelminthic, praziquantel, on the haematological and biochemical indices
of the blood of common carp (Cyprinus carpio L.). Fish were divided into six groups: two groups received 30 mg kg−1 body weight (bw) of praziquantel, and two groups were given 50 mg kg−1 bw of praziquantel mixed into the heat-treated amyloid vehicle. Fish in the remaining two groups were given only the amyloid
vehicle and were used as controls. Fish were examined either 24 or 96 h after administration. Praziquantel treatment was characterised
by a significantly lower erythrocyte count, haemoglobin level, packed cell volume and total protein at both dose levels after
24 h compared with the controls, but these parameters were similar to the control values at 96 h. The activity of alanine
aminotransferase (ALT) was significantly higher after 96 h in the treated groups, which could be attributed to slight hepatocyte
damage caused by praziquantel. However, the differences between the treated and the control groups were not great, and we
presumed that they were reversible. 相似文献
25.
The Russian wheat aphid (=RWA), Diuraphis noxia (Kurdj.) is an exotic expansive aphid on the small grains determined in the Czech republic since 1993 (1995). Determination of RWA flight patterns by suction air traps (= SATs) between 1994-1998 indicated some banker, less important, or indicated RWA distribution areas. A comparison of the RWA monitoring by SATs and by crop samples in areas more or less distant from individual SAT locations manifested a high silmilarity of RWA evidence in its overall distribution and area-influenced population numbers. Owing to geographic area-dependent features of its life-cycle (holocycly) and host plant preferences, RWA seems to be most injurious to spring barley. In spite of the role of SATs in aphid forecasting, RWA samples are recommended to be taken also from the crops at the early ripening stage as the respective SAT evidence reflects only the emigration of the alate aphids originating from the decreasing populations. In general, RWA detection by SATs was either simultaneously or successively found to reflect the RWA presence in the more or less distant crops. The 30km perimeter of a SAT is agreed to be representative for mon-toring RWA populations in a sampled area. 相似文献
26.
Summary A study of pre- and post-fertilisation barriers after interspecific crosses of diploid and tetraploid Trifolium pratense L. and wild species T. alpestre L., T. medium L. and T. sarosiense Hazsl. was aimed at finding of a promising cross combination for obtaining hybrids. The growth of pollen tubes was arrested in interspecific crosses mainly when T. pratense was at a diploid level. To investigate the post-fertilisation barriers in detail, the hybrid embryo viability was traced by two clearing treatments of immature seeds: (1) using chloral hydrate (which proved to be most appropriate); and (2) a mixture of benzyl benzoate and dibutly phthalate. In interspecific combinations T. pratense (4×) × either T. alpestre or T. sarosiense, enlargement of immature seeds occurred, but no hybrid embryo was traced. Of the wild species used as a male parent for crosses, T. medium was the only exception from the point of view of fertilisation. Globular, heart and the early torpedo stages of hybrid embryos were observed 7 days after pollination (DAP) but only when T. pratense was at a tetraploid level. When T. pratense (2×, 4×) was used as a male parent for interspecific crosses with T. alpestre, T. medium and T. sarosiense, strong defects in various stages of embryogenesis were observed, particularly wrinkled and narrowing embryo sacs caused by an expansion of endothelial cells. We conclude with the following finding: (1) to make crosses only in one direction with T. pratense as a female parent and T. medium as a male; (2) to use tetraploid plants of T. pratense; (3) and to excise hybrid embryos at an early torpedo stage, about 7 DAP. 相似文献
27.
Andrea Nies Lilly Proft Marie E. Nehring Christian Gruber Henrieke Sievers Hana Hünigen Ole Gemeinhardt Kenneth C. Richardson Bernhard Hiebl 《Anatomia, histologia, embryologia》2020,49(5):620-626
The purpose of this study was to gain knowledge about the micromorphology of the porcine common carotid artery (CCA) during the period of growth over the bodyweight range of 10–40 kg. CCA samples from German landrace pigs (DL) aged either 2 or 3 months (DL-2 and DL-3) were compared with samples from Göttingen minipigs (GM) aged either 18 or 40 months (GM-18 and GM-40) using transmitted light (phase-contrast mode) and transmission electron microscopy. The GM-18, GM-40 and the DL-3 groups had typical muscular artery histological characteristics. Contrasting to this, the 2-month-old DL pigs had a transitional artery type being characterized by a significantly higher proportion of elastic fibres and a significantly lower number of smooth muscle cells than did the 1 month older DL-3. During the period of maturation, the tunica media of the CCA in GM animals thickened by 1.3× and in DL animals by 2.5× resulting in an overall increased vessel wall thickness. The cumulated thickness of the tunica interna (endothelium, stratum subendotheliale and internal elastic lamina) and the tunica media (including the external elastic lamina) of DL-3 and GM-40 pigs were similar to each other and comparable to that of humans. With an increasing vessel wall thickness, the luminal diameter decreased in GM by 19% and in DL by 11%. Additionally, in the older age groups, GM-40 and DL-3, the internal elastic lamina principally was continuous, but there were also interrupted large segments of elastic lamina separated by gaps. In addition, the principal internal elastic lamina was duplicated in several places. 相似文献
28.
Zdeňka Svobodová Jana Máchová Hana Kroupová Miriam Smutná Ladislav Groch 《Aquaculture International》2007,15(3-4):277-286
Three case studies of ammonia autointoxication of the common carp (Cyprinus carpio L.) are described. In the first case, carp yearlings with a full digestive tract were transferred during the growing period
from pond water (22°C) to tap water (17°C). In the second case, marketable carp were transferred from the fishing ground of
a pond (18°C) to a storage pond (10–12°C). Harvest was performed in late September when the fish were still ingesting natural
feed. In the third case, marketable carp after storage for 1 month were transferred to storage ponds with markedly lower water
temperature. Stress because of harvest and handling also occurred in this case. In all cases, highly increased concentrations
of ammonia were found in the blood plasma of the fish (mean ± SD 1760 ± 350 μmol L−1 in the first case, 870 ± 540 μmol L−1 in the second case, and 880 ± 150 μmol L−1 in the third case). Highly congested, dark-red coloured, oedematous gills were observed for all specimens. We can avoid similar
cases of ammonia autointoxication by protection of fish from sudden changes of temperature during rearing, harvesting, and
handling. 相似文献
29.
Bártíková H Vokřál I Forstová-Křížová V Skálová L Lamka J Szotáková B 《Veterinary parasitology》2011,176(1):27-33
Albendazole (ABZ) is one of the most important benzimidazole compounds possessing high activity against the lancet fluke, Dicrocoelium dendriticum. ABZ sulphoxide (ABZ.SO) is the main molecule present in the bloodstream of an ABZ-treated host. The aim of this study was to characterise the pattern of ex vivo uptake of ABZ and ABZ.SO by lancet flukes and the export of both anthelmintics from these parasites. Transport of these anthelmintics in both living and dead flukes was compared. The adult flukes were collected from mouflons (Ovis musimon) which had been infected naturally. Results showed that more lipophilic ABZ was imported to a higher extent than ABZ.SO, and that significantly higher concentrations of ABZ were detected within living flukes as compared to dead ones. The same pattern was revealed in the study of ABZ and ABZ.SO export from the flukes' bodies. In addition to passive diffusion, active ABZ uptake and active efflux of ABZ and ABZ.SO in D. dendriticum could be assumed. 相似文献
30.
The fate of the fungicide in stored citrus fruit treated with wax coatings containing either sodium 2-phenylphenate (SOPP) or biphenyl was studied. The 2-phenylphenol content of SOPP—treated fruits was virtually unchanged during storage, was localised in the peel and could not be detected in the vapour phase. The persistence of this fungicide on fruit is in accord with the satisfactory results obtained with SOPP waxes. Biphenyl volatilised from biphenyl-waxed fruit at rates reflecting the conditions of storage. The volatilisation of biphenyl accounts for the protective action of biphenyl-waxes and their time limited effect. 相似文献