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11.
Objective – To compare the incidence of seizures in dogs with intervertebral disk disease after iopamidol or iomeprol myelography, and to assess whether the incidence of seizures differed between the 2 agents when severity of neurological deficits, location of cord compression, duration of anesthesia, site of myelogram, volume of contrast, and concentration of contrast were evaluated. Design – Retrospective study. Setting – Veterinary teaching hospital. Animals – One hundred and sixty‐one client‐owned dogs with intervertebral disk disease. Interventions – Subarachnoid injection of contrast medium. Measurements and Main Results – One hundred and sixty‐one dogs with intervertebral disk disease were subjected to myelography using iopamidol (n=74) or iomeprol (n=87). Cranial myelography was performed in 31 dogs, caudal myelography in 125 and both cranial and caudal myelography in 5. Seizures occurred in 23 of 161 (14%) dogs. There was no significant difference overall between iopamidol and iomeprol myelography. However, in dogs with thoracolumbar disk extrusion and paraplegia, seizures occurred more frequently after caudal myelography using iopamidol compared with iomeprol. Conclusions – Both iomeprol and iopamidol are suitable for myelography in dogs. Iomeprol is recommended for caudal myelography in paraplegic dogs with thoracolumbar disk extrusion due to the higher incidence of seizures in this group when iopamidol was used.  相似文献   
12.
Downstream passage of European eel Anguilla anguilla (L.) in catchments with pump(s) for water level management is a major concern. Catchment‐wide acoustic telemetry revealed silver eels quickly migrated downstream through unobstructed reaches (= 12; mean ± SD = 17.9 ± 1.9 km/day). Fourteen of 17 acoustic‐tagged eels detected at the pumping station (82.1%) retreated back upstream and ten (58.8%) passed through pumps after delays (9.5 ± 11.0 days). Multi‐beam sonar imaging across the intake screen (55‐mm gaps) revealed that peaks in migration occurred during the nights preceding the new moon but 76.7% retreated back upstream. All passive integrated transponder (PIT)‐tagged eels recaptured (= 56) downstream of a large (2.23‐m diameter) mixed flow pump survived but 96.5% had minor injuries, reduced physical condition and/or abnormal behaviour. By contrast, 64.7% of PIT‐tagged eels recaptured (= 17) downstream of a small (0.8‐m diameter) axial flow pump died. No acoustic‐tagged eels that passed through the small axial flow pump (= 10) performed onward migration at sea, unlike “control” eels released downstream (= 11). This evidence may help develop effective remediation measures, such as operational changes, to maximise escapement of catadromous eel species at pumping stations.  相似文献   
13.
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   
14.
The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall observed order of persistence was ethofumesate > glyphosate > phenmedipham > metamitron > glufosinate-ammonium. Only ethofumesate and glyphosate persisted until the subsequent spring. Seasonal variation in herbicide dissipation was very high and dissipation ceased almost completely during winter. During the 2 year experiment no indication of potential groundwater pollution risk was obtained, but herbicides may cause surface water pollution.  相似文献   
15.
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   
16.
At the "Small Animal Clinic of the University of Veterinary Science" in Brno during four years 442 sick and 178 clinically normal cats were examined in regard to incidence and diagnosis of toxoplasmosis. Using the Sabin-Feldman reaction, antibodies against T.gondii were found in 40.3% of the cats (titer 4-128), whereas by means of complement fixation reaction and microprecipitation in agar gel, antibodies were found in 23.2% (titer 5-80) and 17.1% of the cats, respectively. Eight cats (1.3%) excreted T.gondii oocysts. The number of animals having specific antibodies increased statistically significant with age (P less than 0.01) and with particular hunting habits: it was higher in cats which were usually catching small rodents (P less than 0.01). A lower toxoplasmosis incidence was observed in indoor-cats (P less than 0.005) and in cats fed with boiled food only (P less than 0.005). In 35% of the cats showing no clinical symptoms of toxoplasmosis, there were found antibodies against T.gondii. Comparison of clinically normal and sick cats revealed that antibodies against T.gondii occurred significantly more often in cats with enlarged lymph nodes (P less than 0.01), with a disease of the digestive tract (P less than 0.01), of the liver (P less than 0.01), and of the nervous system (P less than 0.01). Several recommendations for diagnosis and prophylaxis of toxoplasmosis in cats are given.  相似文献   
17.
Diazinon 60 EC (chemical insecticide, organophosphate, active substance diazinon at a concentration of 600 g l−1) is used in fish-farming in well-founded cases as a biocide to suppress excessive propagation of coarse Daphnia zooplankton. At the concentration of 10 μg l−1 (i.e., 100 g per 1 ha at a mean depth of the pond of 1 m), Diazinon 60 EC can highly selectively eliminate Daphnia zooplankton, causes no harm to fish, and relatively quickly decomposes in the aquatic environment. This has been corroborated by results of acute toxicity tests in fish: the 96 h LC50 is 3 mg l−1 for the guppy (Poecilia reticulata) and 10–25 mg l−1 for the common carp (Cyprinus carpio). As demonstrated by embryonic and larval tests of toxicity for the common carp (C. carpio), Diazinon 60 EC at the concentration of 10 μg l−1 causes no harm to the tested, individuals even in these sensitive (critical) stages of ontogeny.  相似文献   
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19.
Macroscopically visible lipid deposition varying in size from pinpoint to 8‐mm diameter was found in spleens of a population of intensively farmed perch, Perca fluviatilis L. over a 24‐month rearing period. Large agglomerates of adipocytes distinguishable from surrounding normal tissue occurred in all individuals with spleen lipidosis. Several affected fish presented total dystrophy of large clusters of hepatocytes. Prevalence of lipidosis was 5.0% at 12 months and 16.6% at 24 months. There was no significant difference between fatty acid profiles of liver or perivisceral fat of perch with and without lipidosis except for linoleic, myristic, γ‐linoleic, cis‐eicosatrienic, palmitooleic acid. Body weight and hepatosomatic, perivisceral fat and splenosomatic indices were not associated with lipidosis. There was no significant effect of lipidosis on mortality or growth.  相似文献   
20.
Worldwide forests fragmentation has lead to a massive increase of habitat edges, creating both negative and positive impacts on birds. While busy highways dissecting forested areas create edges which are known to reduce bird densities due to the disturbing effect of noise, the impacts of logging forest roads with low traffic volumes have rarely been studied. In this study, we compared species richness and similarity of canopy, cavity and shrub guilds of birds along low-traffic forest roads, in forest interior, and at forest edges in secondary forests in central Europe, where the forests have passed through extensive changes toward uniformly compact growths dominated by production conifers. Although we found tree diversity as positively affecting bird richness across all habitats, the bird richness along forest roads was higher than in forest interior but lower than along forest edges. The shrub guild of birds along forest roads resembled this guild along forest edges while canopy and cavity guilds at the roads were more similar to these guilds in forest interior. Forest interior had the highest probability for some guild to be absent. We conclude that low-traffic roads lead to increase of habitat heterogeneity in structurally poor forests and attract birds due to additional habitat attributes—including better light conditions—that are scarce in forest interior. Therefore, broader support for higher structural diversification of uniform plantations in central European production forests would benefit bird communities inhabiting these areas.  相似文献   
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