全文获取类型
收费全文 | 4067篇 |
免费 | 261篇 |
国内免费 | 2篇 |
专业分类
4330篇 |
出版年
2023年 | 20篇 |
2022年 | 53篇 |
2021年 | 99篇 |
2020年 | 59篇 |
2019年 | 71篇 |
2018年 | 101篇 |
2017年 | 94篇 |
2016年 | 133篇 |
2015年 | 217篇 |
2014年 | 197篇 |
2013年 | 283篇 |
2012年 | 340篇 |
2011年 | 362篇 |
2010年 | 218篇 |
2009年 | 181篇 |
2008年 | 251篇 |
2007年 | 243篇 |
2006年 | 207篇 |
2005年 | 205篇 |
2004年 | 173篇 |
2003年 | 170篇 |
2002年 | 146篇 |
2001年 | 38篇 |
2000年 | 32篇 |
1999年 | 24篇 |
1998年 | 34篇 |
1997年 | 31篇 |
1996年 | 23篇 |
1995年 | 25篇 |
1994年 | 19篇 |
1993年 | 30篇 |
1992年 | 16篇 |
1991年 | 9篇 |
1990年 | 16篇 |
1989年 | 14篇 |
1988年 | 8篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 12篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 17篇 |
1981年 | 6篇 |
1980年 | 12篇 |
1979年 | 9篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 6篇 |
1974年 | 16篇 |
1966年 | 5篇 |
排序方式: 共有4330条查询结果,搜索用时 0 毫秒
111.
112.
113.
114.
115.
This work shows in vitro processing of Bacillus thuringiensis svar. isralensis Cry toxins and the capacity of the active fragments to bind the midgut microvilli of Aedes aegypti larvae. Processing of Cry11Aa, Cry4Aa and Cry4Ba yielded double fragments of 38-30, 45-20 and 45-18 kDa, respectively. Competition assays showed that all active (125)I-Cry toxins are able to specifically bind to brush border membrane fractions and they might share a common class of binding sites. The values of IC(50) suggested that toxins do not display high affinity for the receptors from brush border membrane fractions, while dissociation assays showed that binding was irreversible, indicating the insertion of toxins in the cell membrane. 相似文献
116.
Van de Vijver G Van Speybroeck L De Waele D Kolen F De Preester H 《Acta biotheoretica》2005,53(2):57-75
This paper analyses the actual meaning of a transcendental philosophy of biology, and does so by exploring and actualising
the epistemological and metaphysical value of Kant's viewpoint on living systems. It finds inspiration in the Kantian idea
of living systems intrinsically resisting objectification, but critically departs from Kant's philosophical solution in as
far as it is based in a subjectivist dogmatism. It attempts to overcome this dogmatism, on the one hand by explicitly taking
into account the conditions of possibility at the side of the subject, and on the other hand by embedding both the living
and the knowing system into an ontology of complexly organized dynamical systems. This paper fits into the transcendental
perspective in acknowledging the need to analyse the conditions of knowability, prior to the contents of what is known. But it also contributes to an expansion and an actualisation of the
issue of transcendentality itself by considering the conditions of possibility at the side of the object as intrinsically
linked to the conditions of possibility at the side of the subject. 相似文献
117.
Interaction of the Saccharomyces cerevisiae cortical actin patch protein Rvs167p with proteins involved in ER to Golgi vesicle trafficking 下载免费PDF全文
We have used affinity chromatography to identify two proteins that bind to the SH3 domain of the actin cytoskeleton protein Rvs167p: Gyp5p and Gyl1p. Gyp5p has been shown to be a GTPase activating protein (GAP) for Ypt1p, a Rab GTPase involved in ER to Golgi trafficking; Gyl1p is a protein that resembles Gyp5p and has recently been shown to colocalize with and belong to the same protein complex as Gyp5p. We show that Gyl1p and Gyp5p interact directly with each other, likely through their carboxy-terminal coiled-coil regions. In assays of GAP activity, Gyp5p had GAP activity toward Ypt1p and we found that this activity was stimulated by the addition of Gyl1p. Gyl1p had no GAP activity toward Ypt1p. Genetic experiments suggest a role for Gyp5p and Gyl1p in ER to Golgi trafficking, consistent with their biochemical role. Since Rvs167p has a previously characterized role in endocytosis and we have shown here that it interacts with proteins involved in Golgi vesicle trafficking, we suggest that Rvs167p may have a general role in vesicle trafficking. 相似文献
118.
Gemma Aragonès Kalavathi Dasuri Opeoluwa Olukorede Sarah G. Francisco Carol Renneburg Caroline Kumsta Malene Hansen Shun Kageyama Masaaki Komatsu Sheldon Rowan Jonathan Volkin Michael Workman Wenxin Yang Paula Daza Diego Ruano Helena Dominguez‐Martín José Antonio Rodríguez‐Navarro Xue‐Liang Du Michael A. Brownlee Eloy Bejarano Allen Taylor 《Aging cell》2020,19(11)
119.
An occurrence of resistance to tetracycline (TET) and erythromycin (ERY) was ascertained in 82 isolates of Enterococcus spp. of animal and environmental origin. Using E test, 33 isolates were resistant to TET and three isolates to ERY. Using polymerase chain reaction (PCR; single and multiplex),
the TET determinants tet(M) and tet(L) were detected in 35 and 13 isolates, respectively. Twelve isolates carried both tet(M) and tet(L) genes. Eight isolates possessed ermB gene associated with ERY resistance. Multiplex PCR was shown to be a suitable method for simultaneous determination of all
three resistance determinants that occurred most frequently in bacteria isolated from poultry. This study also demonstrates
that gastrointestinal tract of broilers may be a reservoir of enterococci with acquired resistance to both TET and ERY that
can be transferred to humans via food chain. 相似文献
120.
Data are presented on the aboveground and underground biomass of the speciesMarsilea quadrifolia and on the water regime and soil conditions in a habitat of this species in Central Europe (Czechoslovakia). 相似文献