全文获取类型
收费全文 | 284篇 |
免费 | 12篇 |
专业分类
林业 | 28篇 |
农学 | 3篇 |
32篇 | |
综合类 | 6篇 |
农作物 | 1篇 |
水产渔业 | 79篇 |
畜牧兽医 | 112篇 |
园艺 | 2篇 |
植物保护 | 33篇 |
出版年
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 4篇 |
2014年 | 11篇 |
2013年 | 25篇 |
2012年 | 10篇 |
2011年 | 16篇 |
2010年 | 6篇 |
2009年 | 12篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 15篇 |
2005年 | 23篇 |
2004年 | 25篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 18篇 |
2000年 | 17篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有296条查询结果,搜索用时 29 毫秒
11.
Protoplasts were isolated from the leaves of sterile plants ofPopulus euphratica Oliv. by using 1% Cellulase “Onozuka” RS and 0.25% Pectolyase Y-23 in 0.6m of mannitol solution. Protoplasts were cultured in modified Murashige and Skoog's (MS) medium which contained no ammonium
ions but was supplemented with BAP (6-benzylaminopurine), 2,4-D (2,4- dichlorophenoxy-acetic acid), and 1% sucrose at the
cell density of 9×104/ml. Cell divisions occurred in every culture medium, especially in the medium containing 0.5 mg/l of BAP and 0.1 mg/l of
2,4-D, in which callus was successfully induced by successive culture through cell cluster formation. Shoots were regenerated
from the callus, and their growth was enhanced on 1/2 MS medium containing 0.8 mg/l of BAP. Finally, shoots were rooted and
plantlets were regenerated on 1/2 MS medium without a hormone.
A part of this paper was presented at the 106th Annual Meeting of the Jpn. For. Soc. (1995). 相似文献
12.
Nocturnal/diurnal demand-feeding pattern of yellowtail Seriola quinqueradiata under different keeping conditions 总被引:1,自引:0,他引:1
13.
Yoshiaki Nakagawa Yoshihiro Soya Katsumi Nakai Nobuhiro Oikawa Keiichiro Nishimura Tamio Ueno Toshio Fujita Norio Kurihara 《Pest management science》1995,43(4):339-345
The ability to stimulate N-acetylglucosamine (GluNAc) incorporation in-vitro of a number of N-tert-butyl-N,N′-dibenzoylhydrazines having various substituents on both phenyl rings was measured in cultured integument excised from the rice stem borer (Chilo suppressalis Walker). The relationship between in-vitro and larvicidal potency was approximately linear. The substituent effects on variations in the potency were similar between in-vitro and larvicidal activities. An inhibitor of oxidative detoxication, piperonyl butoxide, had no synergistic effects on the in-vitro potency. The ability of some dibenzoylhydrazines to inhibit GluNAc incorporation at exposure periods longer than the optimum for stimulation was also measured in a similar cultured integument system. The relationship between the inhibitory and stimulatory potency indices was linear, indicating that the larvicidal activity of dibenzoylhydrazines is closely related to its ability to stimulate as well as to inhibit GluNAc incorporation into the larval cuticle. 相似文献
14.
Hashizume K Takahashi T Shimizu M Todoroki J Shimada A Hirata M Sato T Ito A 《The Journal of reproduction and development》2003,49(1):45-53
In vitro cell culture is a convenient tool for studying cellular mechanisms. In the present study, production of matrix-metalloproteinases (MMPs) in bovine endometrial (containing both epithelial and stromal cells) monolayer cells was examined. Blastocysts attached to the endometrial cells in a monolayer culture were examined for their effects on MMP-2 production. Initial attachment of blastocysts to the monolayer inhibited MMP-2 production by endometrial cells. But once trophoblast cells began to migrate into the endometrial cell layer, MMP-2 production increased, and at the same time MMP-9 production also became evident in the medium. In order to understand how blastocysts affected MMP-2 production, we examined the effect of progesterone, estradiol, insulin-like growth factors (IGFs), tumor necrosis factors (TNFs), and interferon-tau (IFN-tau) supplementation. It was IFN-tau that inhibited the production of MMP-2. In addition, progesterone at a lower dose appeared to inhibit MMP-2 production. Both TNF-alpha and TNF-beta strongly stimulated the production of MMP-2 and MMP-9, whereas IGFs had no effect. Based on these findings, it appears that conceptus has the capacity to inhibit MMP activity. 相似文献
15.
Imai K Khandoker MA Yonai M Takahashi T Sato T Ito A Hasegawa Y Hashizume K 《Domestic animal endocrinology》2003,24(2):171-183
Matrix metalloproteinases (MMPs) play very important roles in extracellular matrix (ECM) remodeling during ovarian follicular development, ovulation and atresia. The aim of the present study was to determine the content of gelatinases in follicular fluid in various sized bovine follicles. Bovine ovaries were collected from local slaughterhouse and follicular fluid from follicles of 2 to over 25 mm in diameter was collected. Gelatinase activity within the follicular fluid was analyzed by gelatin zymography. The concentration of inhibin in the follicular fluid was also measured by immunoblot analysis. The proMMP-2 and alpha-subunit (alphaN) inhibin was detected in all follicles regardless of their size. The abundance of proMMP-2 varied with follicular size, while alphaN inhibin increased significantly (P<0.01) in follicles of 10-14 and 15-20 mm in size. There was a positive and negative correlation between estradiol (E(2)) and progesterone (P(4)) concentrations with abundance of proMMP-2, respectively. Follicles of diameter over 25 mm had greater proMMP-9 activity than other follicles. These same follicles had significantly (P<0.01) lower inhibin levels than follicles of 10-14 and 15-20 mm in size. In conclusion, these results suggest a significant role of these proteases in growth and development of bovine follicle, particularly proMMP-2 and active MMP-2 activities in the follicular fluid could serve as markers of follicular health while abundance of proMMP-9 may possibly denote a follicular cyst. 相似文献
16.
Ishioka K Soliman MM Sagawa M Nakadomo F Shibata H Honjoh T Hashimoto A Kitamura H Kimura K Saito M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(4):349-353
Leptin is a protein synthesized and secreted primarily by adipocytes, and the circulating leptin concentration is elevated in obese humans and rodents. Recently, we have established a sandwich enzyme-linked immunosorbent assay for canine leptin. In the present study, plasma leptin concentrations were measured in experimentally developed obese beagles and in clinically obese dogs. When 5 male beagles were given a high-energy diet for 3 months, all of them became obese and the plasma leptin concentration significantly increased from 2.4+/-1.2 to 4.9+/-0.9 ng/ml, positively correlating with body fat content estimated by the deuterium oxide dilution method (r=0.87). The leptin concentrations of plasma samples collected from 59 dogs in veterinary practices were compared with their body condition scores (BCS). The plasma leptin concentrations of obese dogs were 9.7+/-0.7 and 12.3+/-1.5 ng/ml at BCS=4 and BCS=5, respectively, which were significantly higher than those of optimal (BCS=3) dogs (2.7+/-0.3 ng/ml). There was no significant effect of sex and breed. A weak positive correlation (r=0.37) was found between the plasma leptin concentration and age, probably due to the lesser content of visceral fat in puppies younger than 1 year old. These results indicate that plasma leptin is a good index of adiposity in dogs regardless of breed, age and sex, and may be useful for quantitative assessment of obesity in small animal practice. 相似文献
17.
18.
19.
20.