全文获取类型
收费全文 | 5944篇 |
免费 | 579篇 |
国内免费 | 1篇 |
出版年
2023年 | 34篇 |
2022年 | 73篇 |
2021年 | 188篇 |
2020年 | 117篇 |
2019年 | 151篇 |
2018年 | 162篇 |
2017年 | 151篇 |
2016年 | 232篇 |
2015年 | 344篇 |
2014年 | 334篇 |
2013年 | 404篇 |
2012年 | 477篇 |
2011年 | 466篇 |
2010年 | 276篇 |
2009年 | 260篇 |
2008年 | 312篇 |
2007年 | 328篇 |
2006年 | 321篇 |
2005年 | 260篇 |
2004年 | 219篇 |
2003年 | 194篇 |
2002年 | 179篇 |
2001年 | 71篇 |
2000年 | 60篇 |
1999年 | 57篇 |
1998年 | 47篇 |
1997年 | 21篇 |
1996年 | 25篇 |
1994年 | 21篇 |
1992年 | 36篇 |
1991年 | 37篇 |
1990年 | 34篇 |
1989年 | 34篇 |
1988年 | 42篇 |
1987年 | 47篇 |
1986年 | 42篇 |
1985年 | 33篇 |
1984年 | 37篇 |
1983年 | 22篇 |
1982年 | 30篇 |
1979年 | 23篇 |
1978年 | 24篇 |
1977年 | 18篇 |
1976年 | 19篇 |
1975年 | 24篇 |
1974年 | 24篇 |
1973年 | 23篇 |
1972年 | 18篇 |
1971年 | 22篇 |
1970年 | 18篇 |
排序方式: 共有6524条查询结果,搜索用时 15 毫秒
41.
ATP-gamma-S microinjection into Xenopus oocyte prevents progesterone induced maturation. Inhibition is time and dose dependent; 50% inhibition occurs when 50 nl of 0.5 mM ATP-gamma-S solution are microinjected/oocyte 1 hr prior to the hormonal trigger. ATP-gamma-S inhibited oocytes can be induced to mature (100%) following microinjection of extracts containing maturation promoting factor (MPF). Our results suggest that the maturation protein(s) has been stabilized in ovo by ATP-gamma-S microinjection, in its phosphorylated inhibitory form. 相似文献
42.
A one-step clearing and embedding procedure for alizarin red S stained skeletons is described. Embryos are fixed in formalin, skinned and eviscerated. After staining in a 10 mg/liter solution of alizarin red S in 5% aqueous KOH, specimens are dehydrated in a graded series of acetone-polyester monomer solutions. Finally, the specimens are embedded at room temperature in the polyester resin. A special reusable metallic mold is described for embedment of large fetuses. Specimens previously cleared in glycerol can be processed with this method. 相似文献
43.
C. Méjean M. Boyer J. P. Labbé J. Derancourt Y. Benyamin C. Roustan 《Bioscience reports》1986,6(5):493-499
The interaction of two different anti-actin antibody populations with the myosin subfragment 1-F-actin rigor complex has been studied. In contrast with the 1–7 sequence, the 18–28 sequence appears to be strongly implicated in the contact area of the myosin head on the actin polypeptide chain. 相似文献
44.
45.
P D Boyer 《Nucleic acids research》1986,14(18):7505
46.
A comparison of specific antibodies induced by unfolded actins modified either by oxidation or by arylation of lysine residues was reported. We have focused our work on binding properties with filamentous actin and located its preferential antigenic sites for the anti-arylated-actin antibodies in the C-part of the molecule. An interference of anti-oxidized actin antibodies upon actin polymerisation has also been reported. 相似文献
47.
Rodney F. Boyer Barbara E. Schori 《Biochemical and biophysical research communications》1983,116(1):244-250
Ceruloplasmin, a copper ferroxidase, promotes the incorporation of Fe(III) into the iron storage protein, apoferritin. The product formed is identical to ferritin as judged by polyacrylamide electrophoresis and iron/protein measurements. Of several proteins examined, only apoferritin accumulates the Fe(III) produced by ceruloplasmin. When ceruloplasmin was replaced by tyrosinase, which we have shown to have ferroxidase activity, no iron incorporation into apoferritin was observed. It is proposed that Fe(III) is transferred directly and specifically to apoferritin. These data support a more specific role for ceruloplasmin in iron metabolism than has previously been proposed. 相似文献
48.
49.
50.
Yvette Boyer 《Biologia Plantarum》1971,13(1):16-21
Experimental Study of changes in water content during dehydration and rehydration of the Fern: Notochlaena vellea R. Br.—This study takes place after studies made on otherPolypodiaceen Ferns. We have shown that, in these ferns, the survival duration was longer for the subterranean organs than for aerial ones. The problem was to show that this difference is due to a lower dehydration of the subterranean tissues. As far as we looked at the total water deficiency, we did not find any significant difference between the leaves and the meristematic parts of the subterranean organs: the main difference is the rate of rehydration which is higher in subterranean parts. 相似文献