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21.
Two dogs from the same owner were referred for ascending weakness and paresis of 2 to 3 days duration. Electromyography and electroneurography determined that there were normal F-waves, decreased compound action potential, and decreased activity on repetitive nerve stimulation. These findings were valuable in diagnosing botulism in the dogs.  相似文献   
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23.

Background

Previous research has indicated a breed predisposition to gastric carcinoma in dogs. However, results to date are inconsistent since several studies have failed to prove such a predisposition. Better knowledge of breeds at risk could facilitate early detection of gastric carcinoma in dogs. The aim of the study was to retrospectively investigate the proportion and possible breed predisposition to canine gastric carcinoma using the Norwegian Canine Cancer Register for calculations of proportional morbidity ratios (PMRs) for the period 1998–2009.

Results

Histologically verified tumours recorded in the Norwegian Canine Cancer Register were studied (n = 19,715). A total of 31 (0.16%) cases of canine gastric carcinomas were identified. The median age of affected dogs was 10 years. The most commonly reported clinical signs were vomiting, anorexia, and weight loss. Males had significantly higher odds of gastric carcinoma than females (P = 0.02). The PMR with 95% confidence interval (CI) was calculated for each breed, and a breed predisposition was identified. Individuals of the breeds Tervuren (PMR 56.1), Bouvier des Flandres (PMR 36.5), Groenendael (PMR 34.5), Collie (PMR 26.1), Standard poodle (PMR 7.6), and Norwegian elkhound (PMR 6.1) had a significantly increased risk of developing gastric carcinoma.

Discussion and conclusion

The proportion of cases of gastric carcinoma recorded in the Norwegian Canine Cancer Register was found to be 0.16%, and a breed predisposition was identified. The breed predisposition observed in the current study indicates a genetic susceptibility to gastric carcinoma.  相似文献   
24.
The objectives of this study were to describe the incidence of, survival until, and survival after the diagnosis of canine bone tumors by breed, sex, age, and geographic location of residence. Dogs under 10 y old and insured by a Swedish insurance company between 1995 and 2002 were studied. In total, 764 dogs had claims for bone tumors, and the incidence rate was 5.5 cases per 10 000 dog-years at risk (DYAR). At ages 6, 8, and 10 y, the proportions of dogs with bone tumors were 0.13%, 0.30%, and 0.64%. The top 3 breeds at risk were Irish wolfhound, St. Bernard, and leonberger (incidence rates 99, 78, and 53 cases per 10 000 DYAR, respectively). Median survival time after diagnosis was 56 d in the 419 dogs that survived > or = 1 d. With a Cox regression model controlling for breed and age, females were shown to be at decreased risk of bone tumors, with a hazard ratio of 0.71 (99% confidence interval 0.58 to 0.87).  相似文献   
25.
Objective-To investigate the hemostatic response to surgery and compare the response for ovariohysterectomy with that for ovariectomy and to evaluate the usefulness of thromboelastography on plasma samples. Animals-42 female dogs. Procedures-Dogs were assigned to undergo ovariohysterectomy or ovariectomy. Blood samples were collected immediately before and 1, 6, and 24 hours after surgery and stored at -80°C for subsequent analysis. Plasma samples were subjected to thromboelastography after thawing. In addition, coagulation variables were measured, including concentrations of von Willebrand factor antigen, fibrinogen, antithrombin, and protein C; activity of factor VIII; activated partial thromboplastin time; prothrombin time; and thrombin time. The fibrinolytic response was assessed via concentrations of D-dimer, plasminogen, and α-2-antiplasmin (plasmin inhibitor). Results-Substantial hemostatic and fibrinolytic activation was evident after surgery in both groups, as characterized by significantly increased global clot strength and an overall hypercoagulable state at 4 hours after surgery in addition to decreases in von Willebrand factor antigen and factor VIII concentrations and shortened prothrombin and thrombin times. The dogs also typically had activation of the fibrinolytic system, as evidenced by increased postoperative concentrations of D-dimer, plasminogen, and plasmin inhibitor. Differences between the 2 groups could not be detected for any variables. Conclusions and Clinical Relevance-Elective surgery with limited tissue trauma induced hemostatic activation in dogs, which led to hypercoagulability after surgery. A difference between the ovariohysterectomy and ovariectomy groups was not detected. Thromboelastography can be used on plasma samples and may be useful for evaluating patterns over time.  相似文献   
26.
  • ? The aim of this work was to study both the effects of genetic entry and competition by neighbouring trees on growth, yield, wood density traits and fibre properties of 20 Norway spruce clones grown in an experimental trial located in southern Finland. The material included 10 Finnish clones, 2 Russian clones and 8 provenance-hybrids clones, the latter ones representing crosses between Finnish and foreign parent trees.
  • ? We found that, compared to growth and yield, wood density traits and fibre properties showed, on average, lower phenotypic variations. Moreover, significant differences could be observed among the clones regardless of the trait (p < 0.05). Conversely, on average, no clear differences could be found between Finnish, Russian and provenance-hybrids clones in most of the studied traits.
  • ? The marked differences among the clones, and lack of clear differences among the provenances suggested that any ranking, regarding different traits, should be based on individual clones. The phenotypic correlations between different traits ranged from moderate to strong suggesting that selection based on one trait would affect other traits. Regardless of clone, the growth of trees (e.g. breast height diameter) decreased and the wood density increased with increasing competition by neighbouring trees, which was expressed by competition index.
  •   相似文献   
    27.
    Potato genotypes were evaluated for resistance to natural infestations of the potato leafhopper,Empoasca fabae (Harris), in the field. Characterization of Type A and B glandular trichomes, phenolic properties of Type A trichomes, glycoalkaloid content and composition,E. fabae adult and nymph infestation, leaf damage (hopperburn), yield, and yield reduction were determined on genotypes PI 473331 and PI 473334 (accessions ofSolatium berthaultii (Hawkes)), NY123 and Q174-2 (advanced hybrids), and Elba and Allegany (commercial cultivars). Regarding the Type A trichome, PI 473334 was most pubescent, followed by PI 473331, both had high levels of enzymatic browning; on PI 473334 no glycoalkaloids were detected, while on PI 473331 solamargine and solasonine were present. Those genotypes were the least infested by adults; moreover, nymphs were never found on their leaves. PI 473331 and Q174-2 possess Type B trichomes, the latter had levels of Type A trichome comparable to the first and to NY123, while displaying high levels of phenolic oxidation of Type A and very low levels of glycoalkaloids. Although Q174-2 had intermediate infestation ofE. fabae, it suffered a yield reduction comparable to the control cultivar Allegany. The density of Type A trichomes of NY123 was relatively low, even though the browning assay results were significantly elevated. Foliage of this genotype was found to contain the four types of glycoalkaloids studied at high levels.Empoasca fabae infestation on NY123 was intermediate, and it yielded well on infested plots, but suffered an intermediate yield reduction. Elba presented densities of Type A similar to NY123. It suffered the lowest yield reduction despite its high levels of leafhopper infestation and hopperburn. Its tolerance might be associated with its phenology, since it is a late-maturing cultivar. High scores of the modified enzymatic browning assay were correlated with high infestation and high leaf damage. Results indicated a significant correlation between leafhopper infestation and hopperburn.  相似文献   
    28.

    Background

    In recent years, the protozoan Tritrichomonas foetus has been recognised as an important cause of chronic large-bowel diarrhoea in purebred cats in many countries, including Norway. The aim of this cross-sectional study was to determine the proportion of animals with T. foetus infection among clinically healthy cats in Norway and to assess different risk factors for T. foetus infection, such as age, sex, former history of gastrointestinal symptoms and concurrent infections with Giardia duodenalis and Cryptosporidium sp.

    Methods

    The sample population consisted of 52 cats participating in three cat shows in Norway in 2009. Samples were examined for motile T. foetus by microscopy, after culturing and for T. foetus-DNA by species-specific nested PCR, as well as for Giardia cysts and Cryptosporidium oocysts by immunofluorescent antibody test (IFAT).

    Results

    By PCR, T. foetus-DNA was demonstrated in the faeces of 11 (21%) of the 52 cats tested. DNA-sequencing of five positive samples yielded 100% identity with previous isolates of T. foetus from cats. Only one sample was positive for T. foetus by microscopy. By IFAT, four samples were positive for Giardia cysts and one for Cryptosporidium oocysts, none of which was co-infected with T. foetus. No significant associations were found between the presence of T. foetus and the various risk factors examined.

    Conclusions

    T. foetus was found to be a common parasite in clinically healthy cats in Norway.  相似文献   
    29.
    ObjectiveTo evaluate the usefulness of intratesticular and subcutaneous lidocaine in alleviating the intraoperative nociceptive response to castration, measured by pulse rate (PR) and mean arterial pressure (MAP), and to test the applicability of heart rate variability (HRV) analysis in assessing this response.Study designRandomized, controlled, observer-blinded experimental trial.AnimalsThirty-nine healthy male cats admitted for castration.MethodsOne group received general anaesthesia and served as control group (GA), while the treatment group (LA) additionally received local anaesthesia (lidocaine 2 mg kg?1) intratesticularly and subcutaneously. PR and MAP were recorded at anaesthesia baseline (T0), treatment (T1), incision left testicle (T2), traction on spermatic cord (T3), tightening of the autoligature and resection of the cord (T4), incision on the right side (T5), traction on spermatic cord (T6), and tightening of the autoligature and resection of cord (T7). HRV analysis was divided into three 5-minute intervals: baseline (H0), treatment (H1), and surgery (H2).ResultsThere were significant increases in PR and MAP for both groups during surgery from T3 onwards; however, the increase in the treatment group (LA) was significantly lower than for the control group (GA). For HRV analysis, significant differences were found between groups in the following parameters during surgery: TP (total power), VLF (very low frequency), SDNN (standard deviation of NN intervals [=the interval between two consecutive R-waves in the ECG]), and TI (triangular index), which were lower in the LA group. Mean NN was significantly lower in the GA group, whereas LF (low frequency) and LFn (low frequency, normalized value) were lower in the LA group. HF (high frequency) and HFn (high frequency, normalized value) decreased significantly from H1 to H2 in both groups.Conclusions and clinical relevanceThe study showed that the nociceptive response to surgery was alleviated by the use of intratesticular and subcutaneous lidocaine and that HRV analysis is a promising research tool to estimate intraoperative nociception in cats during general anaesthesia.  相似文献   
    30.
    Many forest-dwelling species are dependent on deadwood. Sources of deadwood include competition- and senescence-related mortality of trees, and various damages. This study described a methodology for predicting the effect of wind damage on the amount of deadwood and suitability of the forest for saproxylic species. The methodology was used in a forested boreal landscape of 360 ha to analyze the effects of wind damage on the habitat quality for 27 groups of saproxylic species differing in their requirements for the species, size and decay stage of deadwood objects. A reference plan maximized net present value (MaxNPV) while others either minimized or maximized height differences between adjacent stands. Maximization of height differences resulted in high amount of wind damage and deadwood while minimizing height differences minimized wind damage and the amount of damage-related deadwood. The fourth plan maximized the average habitat suitability index (HSI) of the 27 groups of saproxylic species. The plans were compiled with and without even-flow harvesting constraints for three 10-year periods. Maximization of height differences between adjacent stands resulted in higher HSI values than obtained in the MaxNPV plan or in the plan than minimized height differences between adjacent stands. The average HSI of shade-demanding species correlated negatively with the amount of harvested timber. No strong correlations were found for light-demanding and indifferent species.  相似文献   
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