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C Bordas

Publications and source records attributed to C Bordas.

17 recordsLinked to original sources
PubMed2000

Slow photoelectron imaging.

Experiments are reported on the detection of slow photoelectrons resulting from the photoionization of Xe atoms in a dc electric field by electron imaging. In the far-field photoelectron velocity distributions we can distinguish between direct and indirect ionization processes (involving long range Coulomb interactions with the Xe+ ion). Also, a new modulation of the velocity distribution is observed which cannot be explained by previously discussed mechanisms. Classical and quantum mechanical calculations are presented to support the interpretations.

Journal Article↗
PubMed1985

[Frequency of FY and K99 pili in strains of Escherichia coli isolated from diarrheal calves in France].

Epidemiological study of bovine E. coli shows that the FY E. coli pilus which has previously been described and is also known as Att25, can be found in 30 of 415 fecal samples of diarrheic calves, eight of them carrying both FY and K99 pili. The K99 E. coli pilus is present in 86 fecal samples. Strains carrying both FY and K99 pili account for 9% of K99 enterotoxigenic E. coli. K99-, FY+ E. coli do not produce the thermostable enterotoxin (TSa). K99+, FY- or K99+, FY+ E. coli are present mainly in calves under three days old but K99- FY+ E. coli are found whatever the age of the animal.

Age Factors↗
PubMed1981

[Incidence of rotavirus infection and in combined infection of rotavirus and enteropathogenic Escherichia coli in French calves (author's transl)].

Detection of a rotavirus in faeces of 789 calves developing diarrhoea gave positive results among 48% of the calves. The same investigation extended to 96 apparently healthy animals shows that 12.5% of the faeces contained rotavirus. It appears that all the last ones cannot be considered as healthy controls. Association of rotavirus and E. coli K99+ is found in 5% of sick animals less than 10 days old.

Age Factors↗
PubMed1981

[Frequence of K99 antigen and antibioresistance in Escherichia coli from calves in France (author's transl)].

During the winter of 1979-1980, an epizootiological study of diarrhoeic calves revealed the presence of K99+ E. coli among 8.2 p. cent of clinically healthy calves and in 18.9 p. cent of diseases calves. Some calves which seemed healthy on the day of sampling possibly became diarrhoeic on the following days. In diarrhoeic calves, K99+ E. coli were mainly found during the early life, i.e. in 33.7 p. cent of calves less than 4 days old. These results were obtained with 147 healthy calves and 1053 diarrhoeic calves. They confirmed previous results obtained with more limited numbers of animals. Moreover, K99+ E. coli were found in all breeding systems. Antibiotics resistance among the isolated E. coli were very high, especially in K99+ strains. The results proved the interest of E. coli K99 diagnosis in liquid diarrhoea of very young calves.

Age Factors↗