全文获取类型
收费全文 | 42篇 |
免费 | 20篇 |
出版年
2020年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2006年 | 1篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1987年 | 2篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 3篇 |
1969年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有62条查询结果,搜索用时 265 毫秒
11.
Autolytic Enzyme System of Streptococcus faecalis III. Localization of the Autolysin at the Sites of Cell Wall Synthesis
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Gerald D. Shockman Harold M. Pooley J. Stuart Thompson 《Journal of bacteriology》1967,94(5):1525-1530
Cell walls from exponential-phase cultures of Streptococcus faecalis ATCC 9790 autolyzed in dilute buffers. Walls were isolated from cultures grown in the presence of (14)C-lysine for about 10 generations and then on (12)C-lysine for 0.1 to 0.8 of a generation (prelabeled). These walls released (14)C to the soluble fraction more slowly than they lost turbidity during the initial stages of autolysis. Walls isolated from cultures grown in the presence of (14)C-lysine for only the last 0.1 to 0.4 of a generation (postlabeled) released (14)C to the supernatant fluid more rapidly than they lost turbidity. Autolysin in both pre- and postlabeled walls was inactivated, and such walls were then incubated in the presence of unlabeled walls containing active autolysin. The inactivated walls lost their (14)C label only very slowly until autolysis of the unlabeled walls was virtually complete and release of soluble autolysin was expected. When this experiment was done in the presence of trypsin, a fourfold increase in the autolysis rate resulted, but the same pattern of (14)C release was observed. A parallel release of (14)C and loss of turbidity from pre- or postlabeled walls was observed upon trypsin "activation" and by addition of isolated soluble autolysin to inactivated walls. We conclude that the wall-bound autolysin acts first on the more recently synthesized portion of the wall. Trypsin appears to speed wall autolysis by activating additional latent autolysin in situ at sites in the older portion of the wall. 相似文献
12.
Genetic analysis of autolysin-deficient and flagellaless mutants of Bacillus subtilis. 总被引:14,自引:10,他引:4
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Three mutants with an autolysin-deficient and flagellaless phenotype (lyt) were genetically analyzed and compared with three thermosensitive flagellaless mutants. In view of the near indistinguishability of their phenotypes, all six mutations were assigned to fla loci. They were distributed into four linkage groups, designated flaA through flaD. flaA and flaB map between pyrD and thyA, flaD maps between aroD and lys, and, in agreement with a previous report, flaC maps near hisA. A locus associated with hypermotility, ifm-3, maps near the latter marker. Introduction of ifm-3 into lyt-1- and flaA4-containing strains led to partial suppression of the nonmotile phenotype. We discuss the possibility that the cellular concentration of autolysins is regulated by the expression of fla genes. Discrepancies with respect to previous mapping of flaA and flaB are accounted for. 相似文献
13.
14.
Roy S. Conway W. S. Watada A. E. Sams C. E. Pooley C. D. Wergin W. P. 《Protoplasma》1994,178(3-4):156-167
Summary The ripening and softening of fleshy fruits involves biochemical changes in the cell wall. These changes reduce cell wall strength and lead to cell separation and the formation of intercellular spaces. Calcium, a constituent of the cell wall, plays an important role in interacting with pectic acid polymers to form cross-bridges that influence cell wall strength. In the present study, cationic colloidal gold was used for light and electron microscopic examinations to determine whether the frequency and distribution of anionic binding sites in the walls of parenchyma cells in the apple were influenced by calcium, which was pressure infiltrated into mature fruits. Controls were designed to determine the specificity of this method for in muro labelling of the anionic sites on the pectin polymers. The results indicate that two areas of the cell wall were transformed by the calcium treatment: the primary cell walls on either side of the middle lamella and the middle lamella intersects that delineate the intercellular spaces. The data suggest that calcium ions reduce fruit softening by strengthening the cell walls, thereby preventing cell separation that results in formation of intercellular spaces.Abbreviations EDTA
ethylenediaminotetraacetic acid
- PATAg
periodic acid-thiocarbohydrazide-silver proteinate 相似文献
15.
Layered distribution, according to age, within the cell wall of bacillus subtilis. 总被引:30,自引:22,他引:8
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
H M Pooley 《Journal of bacteriology》1976,125(3):1139-1147
When soluble autolytic activity was added to growing cultures of a mutant possessing a reduced rate of cell wall turnover, there was a delay of more than one generation before solubilization of new cell wall began, in contrast to the immediate increase in the rate of solubilization of old cell wall. A similar delay was found before turnover of new cell wall occurred in the parent, in agreement with a previous report (Mauck et al., 1971). When sodium lauryl sulfate-inactivated cell walls were prepared, the great bulk of the wall formed a uniformly susceptible substrate to added autolytic activity. The immediate solubilization of new wall eliminates insusceptibility to autolytic enzyme as an explanation for the failure to be turned over. There were, however, major differences in the rate of solubilization of wall of different ages. During solubilization of the initial 30% of the cell wall preparation, wall two generations old was solubilized at least seven times faster than wall one-half a generation old. This result is interpreted in terms of differences in accessibility. The cell wall is seen as consisting of a series of layers, the age of which increases with the distance from the membrane, such that wall newly synthesized on the membrane passes out through the thickness of the cell wall layer during subsequent growth and only becomes susceptible to turnover as it reaches the outer surface, largely in the form of a layer, more than one generation after incorporation. 相似文献
16.
Bacillus subtilis α-Phosphoglucomutase Is Required for Normal Cell Morphology and Biofilm Formation
下载免费PDF全文
![点击此处可从《Applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Vladimir Lazarevic Blazenka Soldo Noël Mdico Harold Pooley Sierd Bron Dimitri Karamata 《Applied microbiology》2005,71(1):39-45
Mutations designated gtaC and gtaE that affect α-phosphoglucomutase activity required for interconversion of glucose 6-phosphate and α-glucose 1-phosphate were mapped to the Bacillus subtilis pgcA (yhxB) gene. Backcrossing of the two mutations into the 168 reference strain was accompanied by impaired α-phosphoglucomutase activity in the soluble cell extract fraction, altered colony and cell morphology, and resistance to phages 29 and ρ11. Altered cell morphology, reversible by additional magnesium ions, may be correlated with a deficiency in the membrane glycolipid. The deficiency in biofilm formation in gtaC and gtaE mutants may be attributed to an inability to synthesize UDP-glucose, an important intermediate in a number of cell envelope biosynthetic processes. 相似文献
17.
The development, maturation, and turnover rate of mouse spleen dendritic cell populations 总被引:24,自引:0,他引:24
Kamath AT Pooley J O'Keeffe MA Vremec D Zhan Y Lew AM D'Amico A Wu L Tough DF Shortman K 《Journal of immunology (Baltimore, Md. : 1950)》2000,165(12):6762-6770
Three distinct subtypes of dendritic cells (DC) are present in mouse spleen, separable as CD4(-)8alpha(-), CD4(+)8alpha(-), and CD4(-)8alpha(+) DC. We have tested whether these represent stages of development or activation within one DC lineage, or whether they represent separate DC lineages. All three DC subtypes appear relatively mature by many criteria, but all retain a capacity to phagocytose particulate material in vivo. Although further maturation or activation could be induced by bacterially derived stimuli, phagocytic capacity was retained, and no DC subtype was converted to the other. Continuous elimination of CD4(+)8(-) DC by Ab depletion had no effect on the levels of the other DC subtypes. Bromodeoxyuridine labeling experiments indicated that all three DC subtypes have a rapid turnover (half-life, 1.5-2.9 days) in the spleen, with none being the precursor of another. The three DC subtypes showed different kinetics of development from bone marrow precursors. The CD8alpha(+) spleen DC, apparently the most mature, displayed an extremely rapid turnover based on bromodeoxyuridine uptake and the fastest generation from bone marrow precursors. In conclusion, the three splenic DC subtypes behave as rapidly turning over products of three independent developmental streams. 相似文献
18.
Lazarevic V Soldo B Médico N Pooley H Bron S Karamata D 《Applied and environmental microbiology》2005,71(1):39-45
Mutations designated gtaC and gtaE that affect alpha-phosphoglucomutase activity required for interconversion of glucose 6-phosphate and alpha-glucose 1-phosphate were mapped to the Bacillus subtilis pgcA (yhxB) gene. Backcrossing of the two mutations into the 168 reference strain was accompanied by impaired alpha-phosphoglucomutase activity in the soluble cell extract fraction, altered colony and cell morphology, and resistance to phages phi29 and rho11. Altered cell morphology, reversible by additional magnesium ions, may be correlated with a deficiency in the membrane glycolipid. The deficiency in biofilm formation in gtaC and gtaE mutants may be attributed to an inability to synthesize UDP-glucose, an important intermediate in a number of cell envelope biosynthetic processes. 相似文献
19.
20.
Ma H Zhou Z Wei S Liu Z Pooley KA Dunning AM Svenson U Roos G Hosgood HD Shen M Wei Q 《PloS one》2011,6(6):e20466