全文获取类型
收费全文 | 6763篇 |
免费 | 760篇 |
国内免费 | 1篇 |
出版年
2021年 | 69篇 |
2020年 | 67篇 |
2019年 | 88篇 |
2018年 | 106篇 |
2017年 | 57篇 |
2016年 | 115篇 |
2015年 | 159篇 |
2014年 | 219篇 |
2013年 | 327篇 |
2012年 | 351篇 |
2011年 | 365篇 |
2010年 | 237篇 |
2009年 | 211篇 |
2008年 | 339篇 |
2007年 | 406篇 |
2006年 | 342篇 |
2005年 | 379篇 |
2004年 | 349篇 |
2003年 | 347篇 |
2002年 | 326篇 |
2001年 | 113篇 |
2000年 | 93篇 |
1999年 | 107篇 |
1998年 | 116篇 |
1997年 | 79篇 |
1996年 | 102篇 |
1995年 | 91篇 |
1994年 | 74篇 |
1993年 | 72篇 |
1992年 | 79篇 |
1991年 | 53篇 |
1990年 | 60篇 |
1989年 | 67篇 |
1988年 | 62篇 |
1987年 | 56篇 |
1986年 | 48篇 |
1985年 | 61篇 |
1984年 | 86篇 |
1983年 | 60篇 |
1982年 | 75篇 |
1981年 | 103篇 |
1980年 | 81篇 |
1979年 | 55篇 |
1978年 | 76篇 |
1977年 | 71篇 |
1976年 | 64篇 |
1975年 | 53篇 |
1974年 | 60篇 |
1973年 | 45篇 |
1967年 | 49篇 |
排序方式: 共有7524条查询结果,搜索用时 15 毫秒
11.
12.
Dennis W. Jung Gerald P. Brierley 《Biochemical and biophysical research communications》1982,106(4):1372-1377
Heart mitochondria respiring in the presence of Pi release endogenous K+ to a sucrose medium when an uncoupler is added. The uncoupled mitochondria retain K+, however, if the oxidation of NAD(P)H is prevented by the addition of rotenone or antimycin. Addition of rotenone, once the uncoupler-dependent K+-efflux has been initiated, results in a rapid reduction of NAD(P) and a simultaneous decrease in permeability to K+. These changes are independent of respiration. The results suggest that a latent pathway for K+-permeability is present in the membrane, that it can be opened and closed reversibly, and that it reflects, either directly or indirectly, the redox status of mitochondrial pyridine nucleotides. The possible relationship of this putative pathway to those available for Ca2+ uptake and release is considered. 相似文献
13.
Stimulation of secretion in exocrine secretory glands leads to the phosphorylation of a 22-kDa membrane protein (protein III) whose function is still unknown [Jahn et al. (1980) Eur. J. Biochem. 112, 345-352; Jahn & S?ling (1980) Proc. Natl Acad. Sci. USA 78, 6903-6906]. This report describes the comparison of this protein with phosphorylated membrane proteins of similar molecular mass in platelets and liver. Incubation of platelets with agents which raise the intracellular cAMP concentration results in the phosphorylation of a 22-kDa protein which is also phosphorylated in membrane preparations by endogenous kinases or by exogenous cAMP-dependent protein kinase. It is shown that this protein is distinct from protein III although both proteins have the same molecular mass and are substrates of cAMP-dependent protein kinase. In contrast to platelets, protein III could be demonstrated in liver microsomes. This indicates that the function of protein III is not exclusively linked to the stimulus-secretion coupling in exocrine cells. 相似文献
14.
Gerald Ozanne 《Aerobiologia》1990,6(1):8-10
Summary Under the ?Bois plus? scheme, the CTBA is currently developing a third party certification, based on the Scrivener law, with the aim of defending
the consumers' interests. At this early stage, wood preservatives and treated wood are checked for the efficacy of treatments
in order to ensure the stability and security of works in buildings and civil engineering. According to the different classes
of risks in service, ?Bois plus? provides the most adeguate level of protection. In the close future, the industry is planning to incorporate, with the help
of the CTBA and experts, health criteria within the frame of the ?Bois plus? certification scheme. The means could beSafety indexes, which are objectives of quality for professionals.Safety indexes are concentrations of substances in wood which can be taken as safe for humans and the general environment, while still toxic
for the wood pests.
This attractive experience aims to make with the brandname ?Bois plus? a synonym of efficacy and safety. This approach meets the essential requirements 1, 3, 4 of the 89/106 EEC directive: mechanical
resistance and stability/hygiene, health and environment/safety in use. 相似文献
15.
16.
17.
Recently we demonstrated that ethidium bromide altered the plasma and subcellular membrane glycoproteins in control and virus transformed cells. It is reported here that ethidium bromide also stimulated the membrane associated process of sugar transport. The Km of the virus transformed cells and the ethidium bromide treated cells is the same as that of the control cells while the maximum velocity as compared to the control cells is significantly increased. The transport of 2-deoxy-D-glucose was inhibited by glucose, cytochalasin B and neuraminidase but was unaffected by variations in cell density or pH of the incubation medium. 相似文献
18.
19.
Gerald Scott 《Free radical research》1988,5(3):141-147
Antioxidants and stabilisers are of critical importance in the manufacture and use of polymer artifacts. Most conventional additives are readily leached from plastics or rubbers by foodstuffs or body fluids with consequent danger associated with the potential toxicity in the body. Strategy for the development of biologically “safe” stabilisation systems for polymers are discussed and it is concluded that the attachment of the appropriate reactive functional group to the polymer backbone by “reactive processing” provides the best means of immobilising the functional group to leaching fluids without sacrificing its protective action. 相似文献
20.