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Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups.  相似文献   
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In human epileptic patients, changes in cerebral glucose utilization can be detected 2‐deoxy‐2‐[18F] fluoro‐d ‐glucose positron emission tomography (FDG‐PET). The purpose of this prospective study was to determine whether epileptic dogs might show similar findings. Eleven Finnish Spitz dogs with focal idiopathic epilepsy and six healthy dogs were included. Dogs were examined using electroencephalography (EEG) and FDG‐PET, with epileptic dogs being evaluated during the interictal period. Visual and semi‐quantitative assessment methods of FDG‐PET were compared and contrasted with EEG findings. Three independent observers, unaware of dog clinical status, detected FDG‐PET uptake abnormalities in 9/11 epileptic (82%), and 4/8 healthy dogs (50%). Occipital cortex findings were significantly associated with epileptic status (P = 0.013). Epileptic dogs had significantly lower standardized uptake values (SUVs) in numerous cortical regions, the cerebellum, and the hippocampus compared to the control dogs. The lowest SUVs were found in the occipital lobe. White matter normalized and left‐right asymmetry index values for all pairs of homologous regions did not differ between groups. Visual evaluation of the EEGs was less sensitive (36%) than FDG‐PET. Both diagnostic tests were consensual and specific (100%) for occipital findings, but EEG had a lower sensitivity for detecting lateralized foci than FDG‐PET. Findings supported the use of FDG‐PET as a diagnostic test for dogs with suspected idiopathic epilepsy. Visual and semiquantitative analyses of FDG‐PET scans provided complementary information. Findings also supported the theory that epileptogenesis may occur in multiple brain regions in Finnish Spitz dogs with idiopathic epilepsy.  相似文献   
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Sexually antagonistic genetic variation, where optimal values of traits are sex-dependent, is known to slow the loss of genetic variance associated with directional selection on fitness-related traits. However, sexual antagonism alone is not sufficient to maintain variation indefinitely. Selection of rare forms within the sexes can help to conserve genotypic diversity. We combined theoretical models and a field experiment with Myodes glareolus to show that negative frequency-dependent selection on male dominance maintains variation in sexually antagonistic alleles. In our experiment, high-dominance male bank voles were found to have low-fecundity sisters, and vice versa. These results show that investigations of sexually antagonistic traits should take into account the effects of social interactions on the interplay between ecology and evolution, and that investigations of genetic variation should not be conducted solely under laboratory conditions.  相似文献   
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With automatic plant identification methods, the amount of herbicides used in agriculture can be reduced when herbicides are sprayed only on weeds. In the present study, leaves of oat (Avena sativa) and dandelion (Taraxacum officinale, TAROF) were arranged so that there was overlap between the species, imaged with a pulse amplitude modulation fluorescence camera and photographed with a digital color camera. The fluorescence induction curves from each pixel were parameterized to obtain a set of features and from color photographs, texture features were calculated. A support vector algorithm that also performed feature selection was used for pattern recognition of both data sets. Fluorescence-based identification worked well with oat leaves, producing 92.2 % of correctly identified pixels, whereas the texture-based method often mis-identified the central vein of a TAROF leaf as oat, identifying correctly only 66.5 % of oat pixels. With TAROF that shows a clear dicot-type texture, the texture method was slightly better (96.4 % correctly identified pixels) than the fluorescence method (94.6 %). In fluorescence-based identification, the accuracy varied between entire TAROF leaves, probably reflecting the genetic variability of TAROF. The results suggest that the accuracy of identification could be improved by combining two identification methods.  相似文献   
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Voles inflict damage to silviculture by debarking or severing tree seedlings. The large-scale impacts of vole damage to silviculture, both in terms of severity and financial losses are, however, poorly known. In autumn 2005, cyclically fluctuating vole populations were at their highest in Finland for over 15 years, which led to extensive damage to silviculture during the winter 2005/06. We carried out a nationwide assessment of the incidence, spatial extent and economic value of damage and its relation to vole abundance in privately owned forests during this winter. Damage data were obtained with a questionnaire addressed to the directors of all Forest Management Associations (FMAs) operating in Finland, and vole abundance data from 15 long-term monitoring projects across the country. Voles were confirmed to have destroyed ca. 4.7 million tree seedlings, covering a total effective damage area of ca. 2600 ha. The directors of the FMAs estimated that the actual level of damage was likely to exceed 8.5 million seedlings, or 5400 ha. Roughly 80% of all damage was inflicted on Norway spruce (Picea abies), ca. 10% on Scots pine (Pinus sylvestris) and ca. 10% on birch (Betula sp.) and other species. Considering costs of replanting alone, a most likely very conservative estimate of the financial impact of vole damage during the winter 2005/06 lies between 2.2 and 4.0 million €. The occurrence of damage during the winter was positively related to vole abundance in the previous autumn. This validates vole population monitoring as an effective tool for forecasting near-future damage to silviculture. Our results suggest that if vole populations continue to fluctuate as they currently do, levels of damage to Finnish forests will be great also in the future, far exceeding damage levels recorded in earlier decades.  相似文献   
18.
Three‐dimensional distribution of adult upstream‐migrating Atlantic salmon, Salmo salar L., was studied in three power plant tailrace channels on the large, regulated River Kemijoki in northern Finland using novel pressure sensor radio telemetry. The salmon swam mostly at depths of 1–4 m below the surface, with the salmon‐specific averages ranging from 1.3 to 6.4 m. When approaching a power plant, no change in swimming depth was observed. The horizontal locations of salmon in the two regularly shaped tailrace channels peaked at 5–10 m distance from the shoreline and showed a positively skewed distribution with a tail towards the central part of the tailrace. A graphical presentation of salmon locations in the tailrace channel and data on swimming depth and distance from the shoreline may prove useful in determining the location and design of a fishway entrance and in dimensioning attraction flow.  相似文献   
19.
Effective population size is an important parameter for the assessment of genetic diversity within a livestock population and its development over time. If pedigree information is not available, linkage disequilibrium (LD) analysis might offer an alternative perspective for the estimation of effective population size. In this study, 128 individuals of the Swiss Eringer breed were genotyped using the Illumina BovineSNP50 beadchip. We set bin size at 50 kb for LD analysis, assuming that LD for proximal single nucleotide polymorphism (SNP)‐pairs reflects distant breeding history while LD from distal SNP‐pairs would reflect near history. Recombination rates varied among different regions of the genome. The use of physical distances as an approximation of genetic distances (e.g. setting 1 Mb = 0.01 Morgan) led to an upward bias in LD‐based estimates of effective population size for generations beyond 50, while estimates for recent history were unaffected. Correction for restricted sample size did not substantially affect these results. LD‐based actual effective population size was estimated in the range of 87–149, whereas pedigree‐based effective population size resulted in 321 individuals. For conservation purposes, requiring knowledge of recent history (<50 generations), approximation assuming constant recombination rate seemed adequate.  相似文献   
20.
Serum and milk concentrations of sulphonamides following oral administration of three commercial sulphonamide products to dairy cows were studied. The fate of the N4-acetyl derivatives of the compounds was also monitored. Sulfadimidine was found to have the slowest oral absorption rate compared to sulfametoxypyridazine, sulfa-phenazole and sulfanilamide. Sulfaphenazole was least absorbed. Excretion of the different sulfonamides into the milk was by passive diffusion and was best for the least ionized sulfanilamide followed by sulfadimidine and sulfamethoxypyridazine. The most ionized sulfaphenazole was not found in milk. Sulfanilamides was found to be readily acetylated (and sulfaphenazole to a lesser degree). N4-acetyl-sulfanilamide seemed to be actively secreted from blood into milk in the cow.Key words: sulphonamides, farmaco kinetics, acetylation  相似文献   
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