全文获取类型
收费全文 | 6861篇 |
免费 | 341篇 |
国内免费 | 1篇 |
出版年
2023年 | 28篇 |
2022年 | 37篇 |
2021年 | 88篇 |
2020年 | 55篇 |
2019年 | 82篇 |
2018年 | 121篇 |
2017年 | 131篇 |
2016年 | 161篇 |
2015年 | 170篇 |
2014年 | 229篇 |
2013年 | 353篇 |
2012年 | 612篇 |
2011年 | 811篇 |
2010年 | 377篇 |
2009年 | 163篇 |
2008年 | 530篇 |
2007年 | 523篇 |
2006年 | 462篇 |
2005年 | 407篇 |
2004年 | 330篇 |
2003年 | 306篇 |
2002年 | 242篇 |
2001年 | 86篇 |
2000年 | 157篇 |
1999年 | 92篇 |
1998年 | 80篇 |
1997年 | 30篇 |
1996年 | 17篇 |
1995年 | 25篇 |
1994年 | 13篇 |
1993年 | 19篇 |
1992年 | 31篇 |
1991年 | 18篇 |
1990年 | 15篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 20篇 |
1985年 | 20篇 |
1984年 | 26篇 |
1982年 | 17篇 |
1981年 | 12篇 |
1980年 | 21篇 |
1979年 | 16篇 |
1978年 | 14篇 |
1977年 | 12篇 |
1976年 | 17篇 |
1975年 | 13篇 |
1974年 | 19篇 |
1971年 | 11篇 |
1970年 | 9篇 |
排序方式: 共有7203条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
Karlheinz Grillitsch Pablo Tarazona Lisa Klug Tamara Wriessnegger Günther Zellnig Erich Leitner Ivo Feussner Günther Daum 《生物化学与生物物理学报:生物膜》2014
Despite similarities of cellular membranes in all eukaryotes, every compartment displays characteristic and often unique features which are important for the functions of the specific organelles. In the present study, we biochemically characterized the plasma membrane of the methylotrophic yeast Pichia pastoris with emphasis on the lipids which form the matrix of this compartment. Prerequisite for this effort was the design of a standardized and reliable isolation protocol of the plasma membrane at high purity. Analysis of isolated plasma membrane samples from P. pastoris revealed an increase of phosphatidylserine and a decrease of phosphatidylcholine compared to bulk membranes. The amount of saturated fatty acids in the plasma membrane was higher than in total cell extracts. Ergosterol, the final product of the yeast sterol biosynthetic pathway, was found to be enriched in plasma membrane fractions, although markedly lower than in Saccharomyces cerevisiae. A further characteristic feature of the plasma membrane from P. pastoris was the enrichment of inositol phosphorylceramides over neutral sphingolipids, which accumulated in internal membranes. The detailed analysis of the P. pastoris plasma membrane is discussed in the light of cell biological features of this microorganism especially as a microbial cell factory for heterologous protein production. 相似文献
5.
The level of urine selenium in healthy adult population, 230 persons, was examined. Persons were selected regarding sex, ages, and smoking habits. No differences versus these observations have been found. For a total, group values are 16.96 Se nmol/creatinine mmol, SD=5.44. It is possible from a single-void specimen to express daily excretion of selenium. 相似文献
6.
7.
8.
Anton Pauw Sunshine A. Van Bael Halton A. Peters Steven D. Allison José L. C. Camargo Miguel Cifuentes-Jara Aurlstela Conserva Teresa Garcia Restom Tamara Heartsill-Scalley Scott A. Mangan Gabriela Nunez-lturri Elsie Rivera-Ocasio Mark Rountree Susanne Vetter Carolina Volkmer de Castllho 《Biotropica》2004,36(3):410-413
9.
M. R. Sarić 《Plant and Soil》1987,99(1):197-209
Summary The paper discusses the problems of genetic aspects of plant mineral nutrition in the light of the results presented at the
First and Second Symposia on ‘Genetic Aspects of Plant Mineral Nutrition’ organized in Beograd in 1982 and Madison in 1985,
respectively. On the basis of the results, future directions of research are discussed. The papers deal with the concentration
and content of mineral nutrients in different genotypes, physiological and biochemical aspects of the genetic specificity
of plant mineral nutrition, relations between plant genotypes and nitrogen fixing micro-organism strains, as well as with
some related problems which have been investigated to a lesser extent. Particular attention is paid to papers and problems
referring to genetic and breeding research work linked with genetic aspects of plant mineral nutrition as well as the possibilities
of developing new cultivars requiring certain soil and mineral nutrition conditions for their cultivation. 相似文献
10.
In the lichen genusUsnea different species ofTrebouxia-phycobionts as well as different haustorial types are known. The isolated and cultivated phycobiont ofUsnea longissima
Ach. was studied by light- and electron microscopy and resembles in cytomorphological details the type ofTrebouxia impressa
Ahmad. In addition to simple wall-to-wall contacts between the symbiotic components also intraparietal (=intrawall-)haustoria could be observed as the normal interaction type.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet. 相似文献