全文获取类型
收费全文 | 61篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
林业 | 1篇 |
农学 | 2篇 |
4篇 | |
综合类 | 13篇 |
农作物 | 3篇 |
畜牧兽医 | 32篇 |
园艺 | 1篇 |
植物保护 | 8篇 |
出版年
2021年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2012年 | 1篇 |
2010年 | 3篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2000年 | 8篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1956年 | 1篇 |
1952年 | 1篇 |
排序方式: 共有64条查询结果,搜索用时 0 毫秒
61.
62.
用透射电镜观察了短尾鮠精子细胞和精子的形态以及细胞核、拟染色体和线粒体等的结构变化规律。结果表明,随着精子细胞的发育,核质凝聚程度逐渐增强。精子细胞时期细胞器较丰富,到精子细胞后期,细胞器的形态和数量发生了较大变化。短尾鮠的精子具有椭圆的头部和复杂的中片;近侧中心粒和远侧中心粒靠近核的中央;鞭毛呈9+2轴丝结构,并具有由外膜折迭形成的波浪形的鳍状结构。 相似文献
63.
64.
Fibrin–alginate hydrogel supports steroidogenesis,in vitro maturation of oocytes and parthenotes production from caprine preantral follicles cultured in group 下载免费PDF全文
IR Brito GM Silva AD Sales CH Lobo GQ Rodrigues RF Sousa AAA Moura CEM Calderón M Bertolini CC Campello J Smitz JR Figueiredo 《Reproduction in domestic animals》2016,51(6):997-1009
This study aimed to establish a culture system that improves the in vitro development of caprine preantral follicles. In a first experiment, follicles were encapsulated as a single unit per bead and cultured singly or in groups or with five follicles in the same alginate (ALG) bead for 18 days. In a subsequent experiment, the “five follicles per bead” design was chosen to culture in ALG, fibrin–alginate (FA) or hyaluronate (HA) for 18 days. In a third experiment, we chose the five follicles per bead in FA to culture for 30 days. The culture set‐up of five follicles per ALG bead increased antrum formation and follicle diameter compared to the other culture designs (p < .05). Moreover, under this condition, 44.44% of the oocytes from in vitro cultured preantral follicles reached meiotic resumption. A significant increase of follicle diameter occurred in attachment system and FA (p < .05), but the ALG condition reached the highest among all groups on day 18 (p < .05). Follicles encapsulated in matrix produced more estradiol and progesterone than attachment system (p < .05). The expression of MMP‐9 mRNA was higher in FA than in other groups (p < .05) and similar to antral follicles from in vivo control (p > .05). Only FA group resulted in oocytes matured. After 30 days, oocytes from preantral follicles in vitro grown in FA developed to eight‐cell parthenotes. In conclusion, a culture system using FA supported the development of caprine preantral follicles cultured in group and included in the same bead of hydrogel, improving the oocyte maturation and producing parthenotes. 相似文献