全文获取类型
收费全文 | 40篇 |
免费 | 11篇 |
专业分类
林业 | 5篇 |
农学 | 7篇 |
3篇 | |
综合类 | 1篇 |
水产渔业 | 3篇 |
畜牧兽医 | 30篇 |
植物保护 | 2篇 |
出版年
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 2篇 |
2011年 | 1篇 |
2008年 | 4篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1965年 | 3篇 |
1964年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有51条查询结果,搜索用时 15 毫秒
1.
Seed yield is a major breeding target in tetraploid red clover. We investigated if marker‐assisted parentage analysis can identify progeny plants with two high seed‐yielding parents in tetraploid red clover and if this technique is more advantageous than traditional half‐sib selection. Parentage analysis was successfully performed on the progeny from the 10% highest seed‐yielding genotypes from a second‐cycle family selection trial: 16.0% of progeny were identified with a high seed‐yielding father. However, progeny plants with two high seed‐yielding parents did not produce more seeds than traditionally selected progeny (27.3 g vs. 30.7 g/plant, respectively). The 10% highest seed‐yielding genotypes displayed on average 2% self‐fertilization. Four genotypes were self‐fertile with individual selfing rates up to 20%. Our results discourage the use of marker‐assisted parentage analysis to improve seed yield in tetraploid red clover when the material has been preselected for seed yield. Breeders should be aware that intensive selection for seed yield in tetraploid red clover may inadvertently lead to selection for increased self‐fertility, which may increase inbreeding in the long term. 相似文献
2.
OBJECTIVE: To evaluate the applicability of in vivo confocal microscopy (IVCM) in veterinary ophthalmology and analyze the morphology of living, healthy cornea. ANIMALS EXAMINED: Thirty-seven dogs, 34 cats and five birds. PROCEDURE: Various corneal sublayers were visualized in the central region using an in vivo confocal corneal microscope (HRTII/RCM). RESULTS: An investigation method was developed and adapted for use on animals with varying skull forms and eye positions. Real-time images of the epithelial cells, the corneal stroma and the endothelial layer were obtained. The corneal stromal nerve trunks and the subepithelial and basal epithelial nerve plexus were visualized. In dogs, full corneal thickness (FCT) was 585 +/- 79 microm (mean +/- SD) and endothelial cell density (ECD) 3175 +/- 776 cells/mm(2) (mean +/- SD). In cats, FCT was 592 +/- 80 microm and ECD 2846 +/- 403 cells/mm(2). There were no significant differences between canine and feline FCT and ECD and no morphologic differences could be seen between dogs and cats. The bird images revealed a number of structural differences. CONCLUSION: Noninvasive IVCM allows accurate detection of corneal sublayers, corneal pachymetry, endothelial cell density and corneal innervation in various animal species. For clinical usage, patients must be under general anesthesia. The confocal images provided anatomic reference images of various healthy corneal structures in dogs, cats and birds. 相似文献
3.
Hog Cholera: I. Investigation of the Agar Double-Diffusion Precipitation Test for The Detection of the Virus in Swine Tissue 总被引:4,自引:4,他引:0 下载免费PDF全文
Gerda M. Ruckerbauer M. Appel G. L. Bannister K. Mori Delma Cochrane P. Boulanger 《Canadian journal of veterinary research》1964,28(12):297-303
The agar double-diffusion precipitation test was investigated to detect hog cholera virus in splenic and pancreatic tissues of swine. Special attention was given to the conditions influencing the sensitivity and specificity of the test. These studies emphasize the strict techniques and methods required in the test in order to detect specific antigen — antibody reaction. Absorption studies performed on serum fractions prepared by DEAE cellulose chromatography and studied electrophoretically, indicated the specific reaction was given by fractions, migrating in the gamma-globulin region and was absorbed by infected but not by normal spleens. The sensitivity of the test is dependent to a great extent on the successful liberation of the viral antigen from the tissue. 相似文献
4.
Robertson A. Appel M. Bannister G. L. Ruckerbauer Gerda M. Boulanger P. 《Canadian journal of veterinary research》1965,29(5):113-117
Sera of sheep and calves infected with the California type 10 and Cyprus type 3 viruses of bluetongue were tested by the regular and modified direct complement-fixation tests. To obtain satisfactory complement fixation it was necessary to use the latter test. Cross reactivity was found, therefore, the California type 10 antigen could be used in testing sera of animals infected with the Cyprus virus. 相似文献
5.
6.
Equine Infectious Anemia: Preliminary Investigation of the Complement-Fixation Test for the Demonstration of Antibodies and Antigen 下载免费PDF全文
P. Boulanger G. L. Bannister Gerda M. Ruckerbauer A. H. Corner 《Canadian journal of veterinary research》1969,33(2):148-154
Clinical field cases of equine infectious anemia were studied and the disease was reproduced experimentally in horses. Attempts were made to adapt the complement-fixation test to the detection of antibodies in the serum of infected animals and to the demonstration of antigens in tissue extracts.
A moderate complement-fixing antibody response was demonstrated in the serum of horses shortly after primary exposure to the infectious agent. However, this reactivity was of short duration and occurred with normal as well as with infected saline tissue extracts. It was therefore concluded that this reaction was not specific for equine infectious anemia. Possibly it is due to the appearance of auto-tissue antibodies. The value of this reaction in the diagnosis of the infection was limited because of its short duration and absence in chronic infection and following re-exposure to the infectious agent.
相似文献7.
Wessels G Hamann H Erhardt G Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(9-10):414-419
The frequencies of milk protein variants alphas1-casein, alphas2-casein, beta-casein and beta-lactoglobulin were determined in 182 milk sheep from 7 flocks in Lower Saxony and Saxony. The genotype effects of these polymorphic milk protein variants on milk performance traits were estimated for 173 ewes using a test day model with fixed regression.The model included the fixed effects of colour variant of the breed, region, lambing season, lambing year, lactation number and number of lambs born. The herd and animal effect were treated as random and the days in milk as linear and non-linear covariates. The milk protein variants of alphas1-casein and beta-casein showed a significant relationship to protein content and the variants of beta-casein to milk fat content. Milk fat yield was significantly associated with the milk protein variants of alphas2-casein, whereas the other milk performance traits were not significantly correlated. 相似文献
8.
Red clover (Trifolium pratense) is an important perennial forage crop that is widely cultivated in Europe. Clover rot remains a major disease in red clover, but resistance breeding is hampered by the lack of available sources of resistance. Moreover, little is known about the factors that influence clover rot resistance. In this paper we evaluated the variation in clover rot susceptibility among a diverse collection of 113 red clover accessions, with the aim of identifying more resistant accessions. Clover rot susceptibility was assessed with a high throughput bio-test on young plants. We found significant variation in clover rot susceptibility, within and among accessions. ‘Tedi’, ‘Maro’ and ‘No 292’ were the most resistant accessions. Fifteen diploid accessions were more susceptible than the average accession with the cultivar ‘Nemaro’ being the most susceptible. Clover rot susceptibility was not correlated with isoflavone levels from Mullaney et al. (Agronomy abstract. ASA, Madison, p 195, 2000). Cultivars were more resistant than landraces and wild accessions and tetraploid cultivars were more resistant than diploid cultivars. Besides the in-depth analysis for clover rot susceptibility, possible correlations with plant architecture and other diseases were investigated. Growth habit, branching, plant yield, flowering date and susceptibility to mildew, virus and rust diseases were investigated in a 3-year field trial. Unlike previously suggested, clover rot susceptibility was not correlated with branching or with plant yield over three years. On the other hand, late flowering accessions and accessions with erect growth habit were less susceptible to clover rot. Clover rot susceptibility was not correlated with susceptibility to rust disease (Uromyces trifolii) or viral diseases, but negatively with susceptibility to mildew (Erysiphe polygoni). Because no completely resistant accessions were found, the best way to improve clover rot resistance would be to select recurrently for resistant genotypes among diverse cultivars and landraces with lower susceptibility. Tetraploidisation of diploid populations with a higher resistance level can provide an additional level of protection. 相似文献
9.
10.
Physiological reactions of spruce (Picea abies) on complex SO2- and drought-induced stress. Part 3. Responses of SO2-stressed spruces to subsequent drought-induced stress. SO2-stressed spruces under drought-stress showed less reduced water content, less increased osmotical potential and less restricted photosynthesis compared to spruces without preceding SO2-stress and thus seemed to be in a better physiological situation. Their ability to retain water (in cut-off twigs) as well as their ability to withstand a quick and strong water-loss in the needle-tissue without cell-damage were reduced. Reasons for the temporarily favourable effect of a pre-going SO2-stress in surviving a drought-stress are discussed. 相似文献