全文获取类型
收费全文 | 278篇 |
免费 | 16篇 |
国内免费 | 1篇 |
出版年
2021年 | 2篇 |
2020年 | 1篇 |
2018年 | 2篇 |
2015年 | 6篇 |
2014年 | 9篇 |
2013年 | 15篇 |
2012年 | 10篇 |
2011年 | 6篇 |
2010年 | 8篇 |
2009年 | 12篇 |
2008年 | 3篇 |
2007年 | 7篇 |
2006年 | 10篇 |
2005年 | 6篇 |
2004年 | 12篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 13篇 |
1999年 | 8篇 |
1998年 | 9篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 4篇 |
1988年 | 9篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 8篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 7篇 |
1972年 | 4篇 |
1971年 | 1篇 |
排序方式: 共有295条查询结果,搜索用时 15 毫秒
71.
72.
R A Capaldi 《Archives of biochemistry and biophysics》1974,163(1):99-105
An attempt has been made to identify the large number of components separated in sodium dodecyl sulfate polyacrylamide gels of a mitochondrial inner membrane preparation with the enzymic activities they represent. Individual enzymes and enzyme complexes (electron transfer and the ATP synthesizing and hydrolyzing complexes) were purified and coelectrophoresed with the inner membrane preparation on 10% polyacrylamide gels. Different bands in the densitometric profile of the inner membrane preparation were thus identified with one or more components of one or more of the electron transfer or ATP-synthesizing and -hydrolyzing complexes. Only one major component (band 14), of molecular weight 29,000, was not represented in any of these complexes. It is a hydrophobic protein of as yet unknown function. 相似文献
73.
Schilling B Murray J Yoo CB Row RH Cusack MP Capaldi RA Gibson BW 《Biochimica et biophysica acta》2006,1762(2):213-222
The oxidative phosphorylation system (OXPHOS) consists of five multi-enzyme complexes, Complexes I-V, and is a key component of mitochondrial function relating to energy production, oxidative stress, cell signaling and apoptosis. Defects or a reduction in activity in various components that make up the OXPHOS enzymes can cause serious diseases, including neurodegenerative disease and various metabolic disorders. Our goal is to develop techniques that are capable of rapid and in-depth analysis of all five OXPHOS complexes. Here, we describe a mild, micro-scale immunoisolation and mass spectrometric/proteomic method for the characterization of Complex II (succinate dehydrogenase) and Complex III (ubiquinol-cytochrome c reductase) from bovine and rodent heart mitochondria. Extensive protein sequence coverage was obtained after immunocapture, 1D SDS PAGE separation and mass spectrometric analysis for a majority of the 4 and 11 subunits, respectively, that make up Complexes II and III. The identification of several posttranslational modifications, including the covalent FAD modification of flavoprotein subunit 1 from Complex II, was possible due to high mass spectrometric sequence coverage. 相似文献
74.
The didelphid marsupial, Didelphis aurita, is suggested as an intraguild predator and as key‐species in small mammal assemblages of the Atlantic Forest of Brazil. The field experiments required to test this hypothesis are complex to implement, but the recent revival of regression methods offers a viable alternative. Here we use the dynamic and static regression methods to determine the importance of D. aurita as a competitor and intraguild predator. Capture–recapture data from two localities in the Rio de Janeiro State were used, Garrafão (municipality of Guapimirim), a coastal forest of the Serra do Mar, and Barra de Maricá, a costal sand dune vegetation. Population and microhabitat variables were monitored from April 1997 to April 2003 in Garrafão, and from January 1986 to July 1990 in Barra de Maricá. Microhabitat variables were related to Canopy, Plant, Litter and Rock covers, Obstruction from 0 to 1.5 m, and Number of logs. Exploitation competition was tested by the dynamic method, which models the effects of D. aurita on the per capita growth rate of a species. Interference by predation or competition was tested by the static method, where the abundance of D. aurita at trap stations was regressed against the abundance of other small mammals, after removal of any variation associated with microhabitat factors. Exploitation competition was not detected, but the interference of D. aurita was pervasive, affecting all small mammals studied in the two localities. The clear avoidance of D. aurita by all small mammals tested in two localities of different physiognomies indicates that it functions as an intraguild predator, even if actual predation by D. aurita is an occasional event. 相似文献
75.
We are currently in an interesting phase of plant biotechnology releases, both for the scientists responsible for these innovations who are beginning to see their ideas realized, and for the biotechnology companies that are starting to see a return on their investment. One of the most notable examples, is the introduction of transgenic crops that are engineered to express a Bacillus thuringiensis toxin that confers resistance to insect predation. However, the picture is not altogether positive - there is concern that the introduction of this technology was premature or should not have happened at all, and that the valuable insecticidal properties of Bacillus thuringiensis will be lost. 相似文献
76.
Taylor SW Fahy E Murray J Capaldi RA Ghosh SS 《The Journal of biological chemistry》2003,278(22):19587-19590
We examined the distribution of N-formylkynurenine, a product of the dioxidation of tryptophan residues in proteins, throughout the human heart mitochondrial proteome. This oxidized amino acid is associated with a distinct subset of proteins, including an over-representation of complex I subunits as well as complex V subunits and enzymes involved in redox metabolism. No relationship was observed between the tryptophan modification and methionine oxidation, a known artifact of sample handling. As the mitochondria were isolated from normal human heart tissue and not subject to any artificially induced oxidative stress, we suggest that the susceptible tryptophan residues in this group of proteins are "hot spots" for oxidation in close proximity to a source of reactive oxygen species in respiring mitochondria. 相似文献
77.
78.
Amoresano A; Andolfo A; Siciliano RA; Mele A; Coscarella A; De Santis R; Mauro S; Pucci P; Marino G 《Glycobiology》1998,8(8):779-790
MEN 11300 is a hybrid glycoprotein of 297 amino acids obtained by fusion of
the cDNA encoding GM-CSF with the cDNA encoding EPO followed by
transfection of the hybrid gene into CHO cells. The oligonucleotide
construct incorporated a spacing sequence between the two individual cDNAs
which encodes eight amino acids constituting a linker peptide intended to
separate the GM-CSF and EPO moieties. The recombinant MEN 11300 protein was
submitted to a detailed structural characterization including the
verification of the entire amino acid sequence, the assignment of the
disulfide bridges pattern, the identification of the glycosylation sites
and the definition of the glycosidic moiety, including site-specificity.
Partial processing of the C-terminal Arg residue and the occurrence of
N-glycosylation sites at Asn27, Asn155, Asn169, Asn214 were established.
Moreover, O-glycosylation at Ser257 and at the N-terminal region was also
detected. A large heterogeneity was observed in the N-glycans due to the
presence of differently sialylated and fucosylated branched complex type
oligosaccharides whereas O-linked glycans were constituted by GalGalNAc
chains with a different number of sialic acids. The disulfide bridges
pattern was established by direct FABMS analysis of the proteolytic digests
or by ESMS analysis of HPLC purified fractions. Pairing of the eight
cysteine residues resulted in Cys54-Cys96, Cys88-Cys121, Cys138-Cys292, and
Cys160-Cys164. This S-S bridges pattern is identical to that occurring in
the individual natural GM-CSF and EPO, thus showing that the two protein
moieties in MEN 11300 can independently acquire their native
three-dimensional structure.
相似文献
79.
Use of the 1-(2-fluorophenyl)-4-methoxypiperidin-4-yl (Fpmp) and related protecting groups in oligoribonucleotide synthesis: stability of internucleotide linkages to aqueous acid. 总被引:2,自引:2,他引:0 下载免费PDF全文
The internucleotide linkage of uridylyl-(3'-->5')-uridine (r[UpU]) does not undergo detectable hydrolytic cleavage or migration in ca. 24 hr in 0.01 mol dm-3 hydrochloric acid (pH 2.0) at 25 degrees C. However, unlike r[UpU] and previously examined relatively high molecular weight oligoribonucleotides, oligouridylic acids are very sensitive to aqueous acid under the latter conditions (pH 2.0, 25 degrees C). Thus when the 1-(2-fluorophenyl)-4-methoxypiperidin-4-yl (Fpmp) group is used to protect the 2'-hydroxy functions in the synthesis of r[(Up)9U] and r[(Up)19U], the final unblocking process must be carried out above pH 3 if hydrolytic cleavage and migration are to be avoided. It is demonstrated that the rate of acid-catalyzed hydrolysis of the internucleotide linkages of oligoribonucleotides is sequence dependent. As Fpmp groups may be virtually completely removed from average partially-protected oligoribonucleotides within ca. 24 hr at pH 3 and 25 degrees C, it is concluded that Fpmp is a suitable 2'-protecting group even in the synthesis of particularly acid-sensitive sequences. 相似文献
80.
Unusual pattern of bacterial ice nucleation gene evolution 总被引:5,自引:0,他引:5
Edwards AR; Van den Bussche RA; Wichman HA; Orser CS 《Molecular biology and evolution》1994,11(6):911-920
Bacterial ice nucleation activity (INA+ phenotype) can be traced to the
product of a single gene, ina. A remarkably sparse distribution of this
phenotype within three bacterial genera indicates that the ina gene may
have followed an unusual evolutionary path. Southern blot analyses, coupled
with assays for ice-nucleating ability, revealed that within four bacterial
species an ina gene is present in some strains but absent from others.
Results of hybridization experiments using DNA fragments that flank the ina
gene suggested that the genotypic dimorphism of ina may be anomalous. A
phylogenetic analysis of 16S ribosomal RNA gene sequences from a total of
14 ina+ and ina- bacterial strains indicated that the ina+ bacteria are not
monophyletic but instead phylogenetically interspersed among ina- bacteria.
The relationships of ina+ bacteria inferred from ina sequence did not
coincide with those inferred from the 16S data. These results suggest the
possibility of horizontal transfer in the evolution of bacterial ina genes.
相似文献