全文获取类型
收费全文 | 67篇 |
免费 | 27篇 |
出版年
2022年 | 1篇 |
2019年 | 1篇 |
2017年 | 2篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 2篇 |
2012年 | 2篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2001年 | 5篇 |
1999年 | 2篇 |
1998年 | 11篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1971年 | 2篇 |
1961年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有94条查询结果,搜索用时 15 毫秒
61.
In a study of the marine biological environment in which creosoted pilings are located, a previously unreported species of bacteria was isolated. This species was detected on creosoted piling from 11 widely differing locations and was the predominant species of bacteria found on these piling. The new organism was identified as a gram-negative rod belonging to the genus Pseudomonas and has been named Pseudomonas creosotensis. It has been completely described by the standard morphological and biochemical tests. 相似文献
62.
Synergistic Effect of Herpes Simplex Virus and Cytosine Arabinoside on Human Chromosomes 总被引:2,自引:1,他引:1
下载免费PDF全文
![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The combined treatment of cultures of human embryonic lung cells with herpes simplex virus type 2 and cytosine arabinoside produced a significantly increased number of cells containing multiple chromatid and chromosome breaks. The incidence of such cells was found to be approximately two and one half times greater than the additive effects of virus and cytosine arabinoside induced separately and is therefore synergistic. 相似文献
63.
64.
Greg J Poet Ojore BV Oka Marcel van Lith Zhenbo Cao Philip J Robinson Marie Anne Pringle Elias SJ Arnér Neil J Bulleid 《The EMBO journal》2017,36(5):693-702
Folding of proteins entering the secretory pathway in mammalian cells frequently requires the insertion of disulfide bonds. Disulfide insertion can result in covalent linkages found in the native structure as well as those that are not, so‐called non‐native disulfides. The pathways for disulfide formation are well characterized, but our understanding of how non‐native disulfides are reduced so that the correct or native disulfides can form is poor. Here, we use a novel assay to demonstrate that the reduction in non‐native disulfides requires NADPH as the ultimate electron donor, and a robust cytosolic thioredoxin system, driven by thioredoxin reductase 1 (TrxR1 or TXNRD1). Inhibition of this reductive pathway prevents the correct folding and secretion of proteins that are known to form non‐native disulfides during their folding. Hence, we have shown for the first time that mammalian cells have a pathway for transferring reducing equivalents from the cytosol to the ER, which is required to ensure correct disulfide formation in proteins entering the secretory pathway. 相似文献
65.
Genes essential for the production of a linear, bacterial (1-->3)-beta-
glucan, curdlan, have been cloned for the first time from Agrobacterium sp.
ATCC31749. The genes occurred in two, nonoverlapping, genomic fragments
that complemented different sets of curdlan( crd )-deficient
transposon-insertion mutations. These were detected as colonies that failed
to stain with aniline blue, a (1-->3)-beta-glucan specific dye. One
fragment carried a biosynthetic gene cluster (locus I) containing the
putative curdlan synthase gene, crdS, and at least two other crd genes. The
second fragment may contain only a single crd gene (locus II).
Determination of the DNA sequence adjacent to several locus I mutations
revealed homology to known sequences only in the cases of crdS mutations.
Complete sequencing of the 1623 bp crdS gene revealed highest similarities
between the predicted CrdS protein (540 amino acids) and glycosyl
transferases with repetitive action patterns. These include bacterial
cellulose synthases (and their homologs), which form
(1-->4)-beta-glucans. No similarity was detected with putative
(1-->3)- beta-glucan synthases from yeasts and filamentous fungi.
Whatever the determinants of the linkage specificity of these beta-glucan
synthases might be, these results raise the possibility that
(1-->3)-beta-glucans and (1-->4)-beta-glucans are formed by related
catalytic polypeptides.
相似文献
66.
E A McGraw D J Merritt J N Droller S L O''Neill 《Proceedings. Biological sciences / The Royal Society》2001,268(1485):2565-2570
Estimates of Wolbachia density in the eggs, testes and whole flies of drosophilid hosts have been unable to predict the lack of cytoplasmic incompatibility (CI) expression in so-called mod(-) variants. Consequently, the working hypothesis has been that CI expression, although related to Wolbachia density, is also governed by unknown factors that are influenced by both host and bacterial genomes. Here, we compare the behaviour of the mod(-) over-replicating Wolbachia popcorn strain in its native Drosophila melanogaster host to the same strain transinfected into a novel host, namely Drosophila simulans. We report that (i) the popcorn strain is a close relative of other D. melanogaster infections, (ii) the mod(-) status of popcorn in D. melanogaster appears to result from its inability to colonize sperm bundles, (iii) popcorn is present in the bundles in D. simulans and induces strong CI expression, which demonstrates that the bacterial strain does not lack the genetic machinery for inducing CI and that there is host-species-specific control over Wolbachia tissue tropism, and (iv) infection of sperm bundles by the mod(-) D. simulans wCof strain indicates that there are several independent routes by which a strain can be a CI non-expressor. 相似文献
67.
The α-amylase genes in Oryza sativa: Characterization of cDNA clones and mRNA expression during seed germination 总被引:11,自引:0,他引:11
Sharman D. O''Neill Monto H. Kumagai Arindam Majumdar Ning Huang Thomas D. Sutliff Raymond L. Rodriguez 《Molecular & general genetics : MGG》1990,221(2):235-244
Summary Two cDNA clones, pOS103 and pOS137, were isolated which code for distinct -amylase isozymes in germinating rice seeds. Sequence analysis indicated that the clones encode polypeptides of approximately 48 kDa, both of which possess a signal peptide involved in directing secretion of the protein. Comparison of the two rice -amylase amino acid sequence showed that they are 76% similar to each other, while showing 85% to 90% similarity with other cereal -amylases. A comparison of eleven cereal -amylases also revealed three new conserved regions (I, II, and IV) not previously identified in the animal, bacterial, and fungal -amylases. Regions I and IV are sites for intron splicing while region II' is probably involved in calcium binding. One of the rice a-amylase cDNAs, pOS103, encodes a protein that has two potential N-glycosylation sites, one in the signal peptide and the other in the mature portion of the protein. The cDNA clone, pOS137, encodes an -amylase with a single glycosylation site in the signal peptide, suggesting that the mature OS137 isozyme is not glycosylated. Analysis of the expression of these genes in germinating rice seeds indicated that mRNA corresponding to pOS103 and pOS137 could be detected throughout a 48 h period of seed imbibition. RNA levels, however, were dramatically stimulated by treatment of embryoless half-seeds with exogenous GA3. Our results demonstrate that at least two forms of -amylase are expressed in germinating rice seeds and that the expression of these genes is regulated by the phytohormone GA3.Abbreviations GA
gibberellic acid
- GA3
gibberellic acid3; poly(A)–, polyadenylated
- PPA
porcine pancreatic -amylase
- SSC
0.15 M NaCl, 0.015 M sodium citrate, pH 7.0
- TAA
Taka-amylase 相似文献
68.
Background
Combining data from different ethnic populations in a study can increase efficacy of methods designed to identify expression quantitative trait loci (eQTL) compared to analyzing each population independently. In such studies, however, the genetic diversity of minor allele frequencies among populations has rarely been taken into account. Due to the fact that allele frequency diversity and population-level expression differences are present in populations, a consensus regarding the optimal statistical approach for analysis of eQTL in data combining different populations remains inconclusive. 相似文献69.
John Morris Daniel F. Donnelly Elaine O''Neill Fiona McConnell Fergal O''Gara 《Molecular & general genetics : MGG》1994,242(1):9-16
We have isolated and characterized two multicopy suppressors, mssA and mssB, which suppress the cold-sensitive growth phenotype of the smbA2 mutant of Escherichia coli. The mssA gene is located immediately upstream of the rpsA gene (20.5 min). MssA protein was found to be related to nucleoside monophosphate kinases. The mssB, gene was found to be identical to the deaD gene (69 min), which encodes a putative RNA helicase. The SmbA protein belongs to the aspartokinase family and probably represents a new, fourth aspartokinase species in E. coli. Expression of the smbA gene is essential for cell growth. The smbA2 mutant shows a pleiotropic phenotype characterized by cold-sensitive growth, hypersensitivity to the detergent sodium dodecyl sulfate, and formation of a translucent segment at midcell or at a pole of the cell when grown at 22° C. In addition, some cellular proteins were either increased or decreased in amount in the smbA2 mutant. SmbA may be a regulatory factor in the expression of a battery of genes. MssA and MssB might also relate to the expression of some of these genes. Multiple copies mssA and mssB, suppressed the various phenotypic features of the smbA2 mutant to various extents, suppressing the cold-sensitive growth completely. 相似文献
70.
C Nageswara Raju S Sailaja S Pavan Kumari SJ Dhoble V Ramesh Kumar MV Ramanaiah B Sudhakar Reddy 《Luminescence》2013,28(2):162-168
This article reports on the optical properties of 0.5% mol of Sm3+, Dy3+ ion‐doped B2O3‐TeO2‐Li2O‐AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd‐Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm3+ and Dy3+:LiAlFBT glasses showed a bright reddish‐orange emission at 598 nm (4G5/2 → 6H7/2) and an intense yellow emission at 574 nm (4F9/2 → 6H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm3+ and Dy3+:LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献