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61.
An outbreak of anthrax in Saskatchewan in 2006 affected more than 800 animals at 150 locations. The purpose of this study was to assess the spatial and temporal patterns among the cases to determine if there were any significant trends associated with this outbreak. Case and population data were first analyzed for each individual farm location and then again as aggregate data per rural municipality using spatial and spatiotemporal statistical methods such as Oden's Ipop, Cuzick-Edwards' test, spatial scan test, and other mapping techniques. East central Saskatchewan was identified as a primary high risk area, particularly during July 2006. The results of the study led to the conclusion that within this high-risk region, flooding in spring followed by hot and dry conditions could have been a factor in the development of the outbreak.  相似文献   
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63.
This study assessed how different in-situ lysis soil DNA extraction methods influence the DNA yield, quality and hence the results obtained by bacterial and fungal automated ribosomal intergenic spacer analysis (ARISA). Of the methods tested in three soils, a modified hexadecyltrimethylammonium bromide-dithiotreitol (CTAB-DTT)-based method produced ?3 times more DNA of higher quality than the other methods (260/230 nm ratios=1.64–1.82 and 260/280 nm ratios=1.82–1.89 and extracts were less inhibitory of PCR). DNA extracted by this method also yielded more reproducible ARISA ribotypes (89?119 for bacteria and 48?88 for fungi; P<0.05) than DNA extracted by other methods, and consequently produced more reliable estimates of bacterial and fungal diversity in all three test soils. The significant correlations observed between the numbers of reproducible ribotypes and DNA extract 260/230 nm ratios (r=0.88 and 0.72 for bacteria and fungi, respectively; P<0.001) reaffirmed the strong influence of DNA quality on the reliability of microbial diversity indices determined based on PCR-based DNA fingerprinting technique. Results of discriminant function analysis (DFA) and multivariate analysis of variances (MANOVA) performed on ARISA profiles (number and relative abundance of ribotype) revealed that the variability associated with DNA extraction methods did not exceed the biological variability among soil types; this supports the conclusion that high-quality DNA underpins DNA fingerprinting techniques.  相似文献   
64.
Fishery management frequently involves precautionary buffering for scientific uncertainty. For example, a precautionary buffer that scales with scientific uncertainty is used to calculate the acceptable biological catch downward from the overfishing limit in the US federal fishery management system. However, there is little empirical guidance to suggest how large buffers for scientific uncertainty should be. One important component of uncertainty is variation among different assessments of the same stock in estimates of management-relevant quantities. We analysed commercially exploited marine fish and invertebrate stocks around the world and developed Bayesian hierarchical models to quantify inter-assessment variation in terminal year biomass and fishing mortality estimates, reference points, relative biomass and fishing mortality estimates, and overfishing limits. There was little evidence of inter-assessment bias; stock assessment estimates in the terminal year of the assessment were not consistently higher or lower than estimates of the same quantities in future years. However, there was a tendency for extreme values from the terminal year to be pulled closer to the mean in future years. Inter-assessment variation in all estimates differed across regions, and a longer inter-assessment interval generally resulted in greater variation. Inter-assessment uncertainty was greatest for estimates of the overfishing limit, with coefficients of variation ranging from 17% in Europe (non-EU) to 107% for Pacific Ocean pelagic stocks. Because inter-assessment variation is only one component of scientific uncertainty, we suggest that these uncertainty estimates may provide a basis for determining the minimum size of precautionary buffers.  相似文献   
65.
Fishery managers must often reconcile conflicting estimates of population status and trend. Superensemble models, commonly used in climate and weather forecasting, may provide an effective solution. This approach uses predictions from multiple models as covariates in an additional “superensemble” model fitted to known data. We evaluated the potential for ensemble averages and superensemble models (ensemble methods) to improve estimates of population status and trend for fisheries. We fit four widely applicable data‐limited models that estimate stock biomass relative to equilibrium biomass at maximum sustainable yield (B/BMSY). We combined these estimates of recent fishery status and trends in B/BMSY with four ensemble methods: an ensemble average and three superensembles (a linear model, a random forest and a boosted regression tree). We trained our superensembles on 5,760 simulated stocks and tested them with cross‐validation and against a global database of 249 stock assessments. Ensemble methods substantially improved estimates of population status and trend. Random forest and boosted regression trees performed the best at estimating population status: inaccuracy (median absolute proportional error) decreased from 0.42 – 0.56 to 0.32 – 0.33, rank‐order correlation between predicted and true status improved from 0.02 – 0.32 to 0.44 – 0.48 and bias (median proportional error) declined from ?0.22 – 0.31 to ?0.12 – 0.03. We found similar improvements when predicting trend and when applying the simulation‐trained superensembles to catch data for global fish stocks. Superensembles can optimally leverage multiple model predictions; however, they must be tested, formed from a diverse set of accurate models and built on a data set representative of the populations to which they are applied.  相似文献   
66.

Background

Carnivores are re-establishing in many human-populated areas, where their presence is often contentious. Reaching consensus on management decisions is often hampered by a dispute over the size of the local carnivore population. Understanding the reproductive dynamics and individual movements of the carnivores can provide support for management decisions, but individual-level information can be difficult to obtain from elusive, wide-ranging species. Non-invasive genetic sampling can yield such information, but makes subsequent reconstruction of population history challenging due to incomplete population coverage and error-prone data. Here, we combine a collaborative, volunteer-based sampling scheme with Bayesian pedigree reconstruction to describe the pack dynamics of an establishing grey wolf (Canis lupus) population in south-west Finland, where wolf breeding was recorded in 2006 for the first time in over a century.

Results

Using DNA extracted mainly from faeces collected since 2008, we identified 81 individual wolves and assigned credible full parentages to 70 of these and partial parentages to a further 9, revealing 7 breeding pairs. Individuals used a range of strategies to obtain breeding opportunities, including dispersal to established or new packs, long-distance migration and inheriting breeding roles. Gene flow occurred between all packs but inbreeding events were rare.

Conclusions

These findings demonstrate that characterizing ongoing pack dynamics can provide detailed, locally-relevant insight into the ecology of contentious species such as the wolf. Involving various stakeholders in data collection makes these results more likely to be accepted as unbiased and hence reliable grounds for management decisions.
  相似文献   
67.
OBJECTIVE: To evaluate a human assay for quantification of carboxy-terminal cross-linking telopeptide of type I collagen (CTX-I), assess the influence of age on plasma CTX-I concentration, investigate the relationship between plasma CTX-I and serum osteocalcin concentrations, and determine whether concentrations of plasma CTX-I or serum osteocalcin fluctuate in circadian manner in horses. HORSES: 75 clinically normal horses. PROCEDURE: Cross-reactivity between equine serum CTX-I and CTX-I antibodies in an automated electrochemiluminescent sandwich antibody assay (ECLIA) was evaluated via a specificity test (ie, dilution test) and recovery calculation. Serum osteocalcin concentration was measured with an equine-specific osteocalcin radioimmunoassay. To analyze diurnal variations in plasma CTX-I and serum osteocalcin concentrations, blood samples were obtained hourly during a 24-hour period. RESULTS: Results of the dilution test indicated good correlation (r > 0.99) between expected serum CTX-I concentrations and measured serum CTX-I concentrations. The calculated CTX-I recovery was 97.6% to 109.9%. Plasma CTX-I and serum osteocalcin concentrations were correlated. Plasma CTX-I concentration was inversely correlated with age of the horse. No significant circadian variations in plasma CTX-I and serum osteocalcin concentrations were detected. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the fully automated CTX-I ECLIA can be used for evaluation of plasma and serum samples from horses and may be a useful tool to monitor bone metabolism changes. Horses in this study did not have notable diurnal fluctuations in serum osteocalcin and plasma CTX-I concentrations.  相似文献   
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69.
In 2015 within an initial test for the biological regulation of the White Scale (Diaspididae: Pseudaulacaspis pentagona) in a fruit orchard near house gardens in Pfinztal-Soellingen near Karlsruhe on heavily infested mulberry (Morus nigrum) a predatory gall midge Lestodiplosis diaspidis (Kieffer, 1910) (Nematocera: Cecidomyiidae) has been detected. This is the first record of this beneficial species for Germany. The importance of this gall midge as an antagonist of White Scale should be investigated in further studies.  相似文献   
70.
Little is known about genetic causes of congenital methemoglobinemia in dogs. Here, we report a CYB5R3 mutation in a Pomeranian dog with congenital methemoglobinemia. A 6‐year‐old neutered female Pomeranian dog was investigated for cyanosis noticed during anesthesia for an orthopedic procedure. The history included lifelong mild exercise intolerance and bluish tongue. Methemoglobinemia was diagnosed using co‐oximetry. The CYB5R3 gene was analyzed by comparing the patient's genomic DNA with the reference canine sequence. Mutation functional significance was investigated using snpEff and multispecies protein homology analyses. A homozygous missense single nucleotide CYB5R3 mutation (ATC ? CTC at codon 194) caused a p.Ile194Leu substitution. The pIle194 residue is highly conserved in other mammals, supporting the likely pathogenicity of the substitution. The mutation described here is identical to that associated with familial methemoglobinemia in a family of Japanese Pomeranian dogs. This observation, together with the homozygous mutation found in our case, indicates that the mutant allele may be widespread within the Pomeranian breed internationally.  相似文献   
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