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21.
Arnold S. Bayer David B. Tillman Nelydia Concepcion Lucien B. Guze 《The Western journal of medicine》1980,132(4):294-300
Differentiation of endocarditic from nonendocarditic Staphylococcus aureus (SA) septicemia is prognostically and therapeutically important. A study of 68 cases of either SA or streptococcal sepsis, including 50 cases of SA sepsis of both cardiac and noncardiac origin, was done to determine the presence and titer of serum teichoic acid antibodies (TAA''s) by double immunodiffusion. Thirty-seven uninfected controls were also examined. There was no statistical difference in either incidence or peak TAA titers in endocardial versus deepseated, extracardiac SA sepsis. However, in both of these groups, incidence and peak titers were significantly higher than in intravascular catheter-related SA sepsis, streptococcal endocarditis and controls (P<0.05). Peak TAA titers in SA sepsis develop on admission or shortly thereafter (6 to 11 days) and permit early decisions on degree of tissue infection, likelihood of metastatic seeding and necessity for higher-dose, longer-term antibiotic therapy.Cases of catheter-related SA sepsis with no clinical evidence of metastatic SA seeding and with negative or low-titered (1:1) TAA''s were classified as superficial sepsis. Treatment consisted of short-term, low-dose antistaphylococcal regimens and catheter removal. In posttherapy follow-up after 6 to 12 weeks, all of the patients were cured and no signs of endocarditis or deepseated SA infection developed. 相似文献
22.
The fatty acid composition of membranes of L-forms ofStreptococcus faecalis andProteus mirabilis cultured at different osmolalities and in different osmotic stabilizers was examined.S. faecalis L-forms cultured with sucrose in the medium showed a decrease in the unsaturated fatty acid C181 and an increase in the C18 fatty acid and C19 cyclopropane fatty acid. Fatty acid composition ofS. faecalis L-forms cultured in medium containing 1.8% NaCl was similar to the fatty acid composition of L-forms cultured in brain-heart infusion broth (BHI) without osmotic stabilizer and was between the composition of fatty acids of L-forms in BHI with sucrose and that in BHI without 0.5 M sucrose. InProteus mirabilis L-forms, there were differences between L-forms cultured with and without sucrose, but these differences were not comparable to the changes observed inS. faecalis L-forms.P. mirabilis L-forms cultured with and without NaCl in the medium had similar fatty acid compositions. 相似文献
23.
Summary We have followed, by DNA-DNA hybridization, the variation in the number of copies of prophage P1 relative to two chromosomal markers when the doubling time of the host cells is modified by a change in carbon source. The ratio of P1/chromosome terminus undergoes a twofold decrease when the cell doubling time increases from 24 to 215 min, whereas the ratio of P1/chromosome origin increases 1.4 fold; both ratios tend towards unity at slow growth rates. This suggests that the replication of prophage P1 is not simultaneous with chromosome initiation or chromosome termination. The chromosome replication time is unaffected by the presence of P1, and remains constant over the range of doubling times studied, with a value of about 40 min. Following amino acid starvation, the P1/chromosome origin ratio increases from 0.7 to 0.9, suggesting that P1 retains the ability to replicate after chromosome initiation has stopped and in the absence of essential amino acids. The results are discussed with reference to similar studies done on F and R1. 相似文献
24.
Agns Maisonneuve Isabelle Callebat Lydia Debordes Lucien Coppet 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,583(2)
A sensitive and specific capillary gas chromatographic method has been developed to measure trace amounts of 2,2′-dichlorodiethyl sulphide (sulphur mustard) in environmental or biological samples. Sulphur mustard was isolated from water or plasma by a solid-phase extraction procedure and from blood by liquid—liquid extraction. The accuracy and precision of the methods were demonstrated using replicate analyses of spiked water, plasma or blood: within-run and between-run variabilities were less than 20%. These analytical methods were used to evaluate the rate of sulphur mustard degradation in water or plasma. Good linear calibration curves, with a detection limit of 45 ng/ml, were obtained for quantitation and determination of sulphur mustard in blood following its intravenous administration to rats. Initial toxicokinetic data were obtained. 相似文献
25.
Marc Uzan Renée Favre Edith Gallay Lucien Caro 《Molecular & general genetics : MGG》1981,182(3):462-470
Summary Eight ilvC transducing phages generated from E. coli K12 secondary site lysogens have been analysed genetically and physically. Two of them carry, in addition, the rho gene and its promotor region, but not the cya gene. The ilvO603 mutation has been located between ilvG and ilvE. Electrophoretic analysis of the proteins synthesized by these phages in a system of UV irradiated cells allowed us to assign molecular weights of 55000 and 66000 daltons to the ilvC and the ilvD gene products, respectively, and to show that an ilvG-encoded polypeptide of 60000 daltons is made from an ilvO
- but not from an ilvO
+ phage. The expression of the ilvG gene is discussed in the light of the recent finding of a promoter-attenuator region lying upstream to ilvG. Finally, we have found that one of the ilv phages does not have the classical structure of a transducing phage. 相似文献
26.
Marie-Annick Auger-Buendia Marie-Paule Ollier-Hartmann Armand Tavitian Lucien Hartmann 《Molecular & general genetics : MGG》1981,182(1):164-170
Summary Proteins isolated from ribosomal subunits of various mammalian cells were analysed comparatively by two different methods: a two-dimensional polyacrylamide gel electrophoresis system and a recently described two-dimensional immunoelectrophoresis technique. For this purpose, antisera were raised in rabbits against the total mixture of ribosomal proteins from murine cells. These sera were characterized by ring-test, double immunodiffusion and two-dimensional immunoelectrophoresis. They were shown to contain antibodies to a large number of ribosomal proteins. Immunoelectrophoretic analysis of 60S and 40S subunit proteins from rabbit, lamb, canine and human cells using anti-murine sera revealed a striking conservation of their antigenic properties. These results corroborated those obtained by two-dimensional polyacrylamide gel electrophoresis. 相似文献
27.
Lynn Silver Michael Chandler H. E. David Lane Lucien Caro 《Molecular & general genetics : MGG》1980,179(3):565-571
Summary The drug resistance plasmid R100.1 can integrate into the E. coli chromosome at several sites on the plasmid. Many of the resulting Hfr strains continuously produce extrachromosomal circular forms of the r-determinant. These r-det plasmids seem incapable of stable autonomous replication. We show that their presence in the cell requires the continuous activity of functional recA and recC genes but does not require the lexA function.The production of r-det circular forms is correlated with an increased copy number of r-det sequences, relative to RTF sequences. This copy number increase is, however, also found in a recA
- backgound where no circular forms of r-det are found. These results show that a specific replication of r-det sequences, not present in the wild-type R100.1 plasmid, occurs in these R-Hfr strains. They suggest that a rec promoted recombination, posterior to the specific replication event, is needed for the production of circular r-det forms. 相似文献
28.
Naohide Yamamoto John W. Philbeck Adam J. Woods Daniel A. Gajewski Joeanna C. Arthur Samuel J. Potolicchio Jr Lucien Levy Anthony J. Caputy 《PloS one》2014,9(5)
Path integration is a process in which observers derive their location by integrating self-motion signals along their locomotion trajectory. Although the medial temporal lobe (MTL) is thought to take part in path integration, the scope of its role for path integration remains unclear. To address this issue, we administered a variety of tasks involving path integration and other related processes to a group of neurosurgical patients whose MTL was unilaterally resected as therapy for epilepsy. These patients were unimpaired relative to neurologically intact controls in many tasks that required integration of various kinds of sensory self-motion information. However, the same patients (especially those who had lesions in the right hemisphere) walked farther than the controls when attempting to walk without vision to a previewed target. Importantly, this task was unique in our test battery in that it allowed participants to form a mental representation of the target location and anticipate their upcoming walking trajectory before they began moving. Thus, these results put forth a new idea that the role of MTL structures for human path integration may stem from their participation in predicting the consequences of one''s locomotor actions. The strengths of this new theoretical viewpoint are discussed. 相似文献
29.
Avadí Angel Hodomihou Nounagnon Richard Amadji Guillaume Lucien Feder Frédéric 《The International Journal of Life Cycle Assessment》2021,26(10):1977-1997
The International Journal of Life Cycle Assessment - The goal of this work is to analyse the environmental impacts across the productive continuum of market gardening in southern Benin, to... 相似文献
30.
Russel J. Reiter Sergio D. Paredes Lucien C. Manchester Dan-Xian Tan 《Critical reviews in biochemistry and molecular biology》2013,48(4):175-200
The discovery of melatonin and its derivatives as antioxidants has stimulated a very large number of studies which have, virtually uniformly, documented the ability of these molecules to detoxify harmful reactants and reduce molecular damage. These observations have clear clinical implications given that numerous age-related diseases in humans have an important free radical component. Moreover, a major theory to explain the processes of aging invokes radicals and their derivatives as causative agents. These conditions, coupled with the loss of melatonin as organisms age, suggest that some diseases and some aspects of aging may be aggravated by the diminished melatonin levels in advanced age. Another corollary of this is that the administration of melatonin, which has an uncommonly low toxicity profile, could theoretically defer the progression of some diseases and possibly forestall signs of aging. Certainly, research in the next decade will help to define the role of melatonin in age-related diseases and in determining successful aging. While increasing life span will not necessarily be a goal of these investigative efforts, improving health and the quality of life in the aged should be an aim of this research. 相似文献