全文获取类型
收费全文 | 93篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
17篇 | |
综合类 | 8篇 |
农作物 | 2篇 |
水产渔业 | 4篇 |
畜牧兽医 | 58篇 |
植物保护 | 7篇 |
出版年
2019年 | 1篇 |
2018年 | 1篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 4篇 |
2007年 | 1篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 3篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 5篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1979年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1964年 | 3篇 |
1959年 | 1篇 |
1956年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有96条查询结果,搜索用时 31 毫秒
81.
C Gabler A Plath-Gabler GJ Killian B Berisha D Schams 《Reproduction in domestic animals》2004,39(5):321-327
82.
GF Mastromonaco E Semple C Robert GJ Rho DH Betts WA King 《Reproduction in domestic animals》2004,39(6):462-467
Important differences exist between in vitro fertilized (IVF) and nuclear transfer (NT) bovine embryos. Studies have shown that although in vitro development is comparable, post-implantation survival is greatly reduced in NT embryos. In this study, we compare serum and bovine serum albumin (BSA) supplementation during oocyte maturation and embryo culture of IVF and NT embryos. In experiment 1, oocytes and embryos were randomly distributed into different treatment groups consisting of synthetic oviductal fluid (SOF) medium supplemented with either serum, fatty acid-free BSA (FAF) or fraction V BSA during maturation and/or culture to assess IVF embryo development. In experiment 2, oocytes were matured in SOF + serum or SOF + FAF and reconstructed embryos were cultured in SOF + FAF to assess NT embryo development. Among the IVF treatment groups, a greater number of blastocysts were observed in the steer serum (SER) group (IVM and IVC in SOF + serum) on day 6; however, no significant differences were seen in blastocyst development from day 8 onwards. Hatching frequencies on days 8 and 9 were significantly greater in groups with serum, with the exception of FAF (IVM and IVC in SOF + FAF) on day 9. For the NT treatment groups, the presence of serum during IVM resulted in a higher proportion of MII oocytes and increased blastocyst development and hatching rates were compared with supplementation of FAF. These results indicate that both serum and FAF provide comparable embryo development for IVF but not for NT bovine embryos. 相似文献
83.
Summary. Post harvest soil samples taken during the autumn of 1985 and 1986 were split and estimates made of the weed seedbank using two methods: (1) a physical separation of seed from the soil mineral fraction by a sieving/flotation procedure and (2) by placing soil in shallow containers in a greenhouse where seeds could germinate and be periodically counted over a period of eight months. Seedbank estimates derived from each procedure were analysed to determine the suitability of each technique for detecting treatment differences from an experiment evaluating tillage/herbicide effects on weed populations. Both techniques were suitable for determination of seedbank changes due to different tillage treatments and herbicide inputs. The two techniques also proved effective for detection of individual species in the seedbank and the two techniques provided comparable estimates of the relative density of individual weed species in the seedbank. Weed seedbank estimates obtained by the physical extraction procedure from the autumn 1985 soil samples were correlated with weed seedling counts made in the spring of 1986. In most cases, weed seedlings represented less than 10% of the number of seeds estimated by physical extraction the preceding autumn. Individual species seed estimates and subsequent weed counts were poorly correlated which indicated that the seed count estimates alone were poor predictors of weed flora. 相似文献
84.
85.
86.
Objective To assess the effectiveness of cobalt pellets in maintaining adequate vitamin B12 in beef cows on pasture of low cobalt content.
Design A field experiment in a herd grazing cobalt deficient pasture.
Animals Mature Murray Grey cows.
Procedure Cows were given a single oral dose of 0, 1, 2 or 4 cobalt pellets (30 g pellets containing 30% by weight cobaltic oxide) with a selenium pellet and a grub screw. Samples of blood, liver, faeces and milk for chemical analyses were collected at intervals over a period of 2 years after treatment.
Results A single cobalt pellet raised liver vitamin B12 concentration of cows above that of untreated cows for at least 28 weeks, and 2 or 4 pellets for 57 weeks. Plasma vitamin B12 concentration was an unreliable indicator of the effectiveness of cobalt pellet therapy. Milk vitamin B12 and faecal cobalt concentrations increased in response to cobalt pellet therapy.
Conclusion These studies show that one cobalt pellet will prevent vitamin B12 inadequacy in beef cows for between 28 and 57 weeks; two or four pellets will prevent inadequacy for 57 to 75 weeks. Milk vitamin B12 concentration may be a useful indicator of the effectiveness of cobalt pellets in increasing the vitamin B12 supply in lactating cows. 相似文献
Design A field experiment in a herd grazing cobalt deficient pasture.
Animals Mature Murray Grey cows.
Procedure Cows were given a single oral dose of 0, 1, 2 or 4 cobalt pellets (30 g pellets containing 30% by weight cobaltic oxide) with a selenium pellet and a grub screw. Samples of blood, liver, faeces and milk for chemical analyses were collected at intervals over a period of 2 years after treatment.
Results A single cobalt pellet raised liver vitamin B
Conclusion These studies show that one cobalt pellet will prevent vitamin B
87.
88.
SP DJORDJEVIC GJ EAMENS LF ROMALIS PJ NICHOLLS V TAYLOR J CHIN 《Australian veterinary journal》1997,75(7):504-511
Objective To investigate the protective efficacy of a pool of denatured membrane protein antigens of Mycoplasma hyopneumoniae (J strain) in the molecular size range 70 to 85 kDa (F3 antigen) in combination with adjuvants for pigs challenged with M hyopneumoniae .
Design A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses.
Procedure F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection.
Results Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection.
Conclusion Pigs vaccinated with M hyopneumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia. 相似文献
Design A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses.
Procedure F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection.
Results Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection.
Conclusion Pigs vaccinated with M hyopneumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia. 相似文献
89.
90.
Different developmental stages of the inflorescence of pearl millet (Pennisetum americanum) were inoculated with zoospores of the downy mildew fungus (Sclerospora graminicola). Individual florets within a panicle were infected, with resultant malformation of any floral organs that were not fully differentiated at the time of infection. 'Green-ear' symptoms resulting from hyperplasia and hypertrophy of the host tissues were accompanied by both sexual and asexual sporulation of the fungus on the malformed plant parts. No grain set occurred in affected florets, indicating that secondary inoculum was able to cause yield reductions even at late stages in the host development. Infection of differentiated stigmas led to rapid dissolution and necrosis of tissue and prevented colonization by the pathogen. This failure suggests that seeds are unlikely to be infected internally. 相似文献