全文获取类型
收费全文 | 56篇 |
免费 | 13篇 |
专业分类
林业 | 1篇 |
1篇 | |
综合类 | 7篇 |
农作物 | 1篇 |
水产渔业 | 9篇 |
畜牧兽医 | 37篇 |
园艺 | 1篇 |
植物保护 | 12篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2007年 | 1篇 |
2006年 | 3篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
排序方式: 共有69条查询结果,搜索用时 15 毫秒
11.
12.
13.
AEF Silva P Rodriguez LF Cavalcante BA Rodrigues JL Rodrigues 《Reproduction in domestic animals》2009,44(S2):259-262
High in vitro oxygen (O2 ) tensions are associated with enhanced levels of reactive oxygen species and cumulus oocyte complex (COC) apoptosis. The objective of this study was to determine the influence of O2 tension on cumulus cell (CC) viability from canine oocytes. Cumulus oocyte complexes were distributed into three groups (CG, T20 and T5) and two O2 tension levels (20% and 5%). The control group (CG) was matured in vitro in a humidified atmosphere with 5% CO2 in air in TCM199 with 26.19 m m sodium bicarbonate, 10% (v/v) foetal calf serum (FCS), 0.10 m m gentamicin, 0.20 m m pyruvic acid, 20 μg/ml oestradiol, 0.5 μg/ml follicle-stimulating hormone, 0.03 IU/ml human chorionic gonadotropin, and 1.0 μg/ml human somatotropin. Groups T20 and T5 were matured under 20% or 5% O2 tensions respectively in a high-glucose medium, without FCS. T20 and T5 were as CG, and supplemented with 0.1% Polyvinyl Alcohol, and 5.5 m m glucose. After 48 h of IVM, CCs from COCs were stained with propidium iodide (1.50 m m ). The results showed that viability of CCs (cytoplasmic features and nuclear morphological integrity) was different for the three groups. Rates of apoptosis were at 57.9% (521/900) for CG, 54.4% (490/900) for T20 and 38.9% (350/900) for T5 (p < 0.001). Predominant features in apoptotic cells (n = 1361) were DNA nuclear fragments (94.0%). It was concluded that CCs of canine COCs cultured in high-glucose medium showed significantly less apoptosis than those cultured in medium with FCS. Low O2 tension was efficient in reducing apoptosis in canine CCs. 相似文献
14.
15.
16.
An enzyme-linked immunosorbent assay (ELISA) for detecting antibody to Mycoplasma hyopneumoniae in porcine serum is described. The results are presented as an ELISA ratio, calculated by dividing the absorbance of the test sample by the mean absorbance of control negative sera. In known infected pigs, the ELISA ratio was highest when the serum concentration applied to the ELISA plate was diluted 1 in 20 in PBS - Tween. Mean ELISA ratios ranged from 1.2 +/- 0.3 for pigs without porcine enzootic pneumonia (PEP) lesions to 5.5 +/- 1.5 for pigs observed with a PEP lesion reacting positively with immunofluorescent histopathology. Pigs observed with typical PEP lesions at slaughter, but not confirmed by immunofluorescent histopathology had a mean ELISA ratio of 4.9 +/- 1.7. The ELISA was highly sensitive (95.6%) and specific (98.8%) when pig sera from commercial piggeries of known M hyopneumoniae infection status were assessed. No cross-reactivity with serum from a pig hyperimmunised with killed M flocculare was detected, and reactivity with serum from another pig hyperimmunised with killed M hyorhinis showed only weak cross-reactivity, which failed to reach the ELISA positive threshold (ELISA ratio 3) for M hyopneumoniae. 相似文献
17.
LF Crocomo F Ariu L Bogliolo D Bebbere S Ledda SD Bicudo 《Reproduction in domestic animals》2016,51(2):276-281
The efficiency of in vitro sheep embryo production is still low compared to that observed in vivo and in other species. In this context, meiotic inhibition strategies emerged as a promising alternative to improve this biotechnology. So, this study aimed to evaluate, for the first time, the effects of roscovitine on in vitro maturation of sheep oocytes and their subsequent embryo development. For this, cumulus–oocyte complexes (COCs) were cultured for 6 h in the presence (Rosco) or absence (Control) of 75 μm roscovitine and, subsequently, in vitro matured (IVM) for 18 h with gonadotropins. At 0 (Immature), 6 and 24 h of culture, the nuclear status of oocytes was evaluated by Hoechst staining. Embryo cleavage and blastocyst formation were recorded 30 h after in vitro fertilization and on day 7 of culture, respectively. Blastocyst quality was evaluated by differential staining. At 6 h, the GV rate in the Rosco treatment (93.8%) was similar to that observed in the Immature oocytes (94.9%) and significantly higher compared to Control (41.3%). After IVM for 18 h, a high and similar proportion of oocytes from Rosco (93.6%) and Control (88.4%) reached the MII stage. In both treatments, approximately 70% of oocytes cleaved and 50% of them developed up to blastocyst. The mean percentage of blastocyst cells, embryoblast, trophoblast and pyknosis did also not differ between Control and Rosco. In conclusion, roscovitine, at the studied experimental conditions, was efficient to reversibly inhibit the meiosis of adult sheep oocytes without detrimental effect on development and quality of the in vitro produced embryos. 相似文献
18.
Determination of site quality is a basic tool for proper selection of locations and species, in management of forest plantations.Throughout the Caribbean studies of site quality are few and are hampered by statistical limitations, inappropriate growth models, and limited data. We fitted growth curves for dominant height to evaluate and classify site quality of teak (Tectona grandis) plantations by using data from 44 permanent sample plots established since 1990 in 3 22 years old teak plantations in the Colombian Caribbean region. We used Korf’s and von Bertalanffy’s models to fit curves as nonlinear effects models. Both models, with a single random parameter, were considered as adequate for dominant height growth modelling, but Korf’s model was superior. There sulting curves were anamorphic and closely reflected high variability insite quality. Five site classes were clarified: at a base age of 12 years old,teak reached a mean dominant height of 24.8 m on the best sites, 9.8 m inthe worst sites, and in the averages sites, 15.8-18.8 m. Using this model,we identified the best and the worst sites for teak plantations in the Caribbean region. This model proved a useful tool, not only for site quality evaluation, but also for improved teak plantation planning and management. 相似文献
19.