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1.
Nat Commun ; 10(1): 658, 2019 02 08.
Article de Anglais | MEDLINE | ID: mdl-30737394

RÉSUMÉ

Polarization-tailored bichromatic femtosecond laser fields with cycloidal polarization profiles have emerged as a powerful tool for coherent control of quantum processes. We present an optical scheme to create and manipulate three-dimensional free electron wave packets with arbitrary rotational symmetry by combining advanced supercontinuum pulse shaping with high resolution photoelectron tomography. Here we use carrier-envelope phase-stable polarization-tailored bichromatic (3ω:4ω) counter- and corotating femtosecond laser pulses to generate 7-fold rotational symmetric and asymmetric photoelectron momentum distributions by multiphoton ionization of sodium atoms. To elucidate the physical mechanisms, we investigate the interplay between the symmetry properties of the driving field and the resulting electron wave packets by varying the optical field parameters. Our results show that the symmetry properties of electron wave packets are not fully determined by the field symmetry, but completely described by multipath quantum interference of states with different angular momenta.

2.
Dtsch Tierarztl Wochenschr ; 104(1): 29-33, 1997 Jan.
Article de Allemand | MEDLINE | ID: mdl-9091283

RÉSUMÉ

The objective of the study was to determine whether precise estimation of rectal temperature of pigs is possible by taking their skin temperature in consideration of different factors as body weight, ambient temperature and relative air humidity. Therefore skin temperature of 272 pigs (7-222 kg BW) was measured by direct (thermo couple element) and indirect (infrared thermometer) methods at distinct localisations. In order to investigate different stages of pyretogenesis Escherichia coli endotoxin was administered to 30 of the pigs intravenously. A significant influence on skin temperature could be ascertained for the ambient temperature and the body weight, but not for the relative air humidity. From these data equations were established to estimate rectal temperature (RT) by measurement the skin temperature (ST) at the base of the ear: 1. Weaners and fattening pigs: RT = ST + 21.867 - 0.089x1 - 0.432x2 + 0.009x3, (r = 0.703) 2. Sows: RT = ST + 31.511 - 0.074x1 - 0.657x2 - 0.011x3, (r = 0.641) (x1 = ambient temperature, x2 = skin temperature, x3 = body weight) In spite of consideration of ambient temperature and body weight estimation of the rectal temperature was not suitable for clear detection of febrile pigs. Only in 35.45% of the younger pigs and in 29.30% of the sows a definite diagnose (fever yes/no) could be made. This method can only be used as a screening in the herd, if estimation of extreme values allowed the recognition of febrile illness. A follow-up control of the rectal temperature is always necessary in groups of animals, where estimations give no clear results.


Sujet(s)
Température du corps , Fièvre/médecine vétérinaire , Température cutanée , Maladies des porcs , Vieillissement , Animaux , Oreille , Fièvre/diagnostic , Rectum , Analyse de régression , Reproductibilité des résultats , Suidae
4.
Infect Immun ; 26(3): 933-41, 1979 Dec.
Article de Anglais | MEDLINE | ID: mdl-528058

RÉSUMÉ

We determined immunoglobulin G (IgG) subclass concentrations and studied their distributions in the cerebrospinal fluids of patients suffering from multiple sclerosis, other inflammatory neurological diseases, and non-inflammatory diseases of the nervous system in comparison with a control group. In addition, the four subclass concentrations were measured in serum specimens of the multiple sclerosis and control groups. These data were correlated with the extent of local IgG synthesis in the subarachnoid spaces of the patients belonging to the different groups. We found a selective elevation of the IgG1 subclass in the cerebrospinal fluids of multiple sclerosis patients, and there was only a very small overlap of the IgG1 ranges of the multiple sclerosis and control groups. No major differences were detected between the IgG subclass distributions in different courses of multiple sclerosis nor between multiple sclerosis and control sera. The group with non-inflammatory diseases showed a uniform elevation of all four subclasses and a greater overlap with the normal range. This latter feature was combined with an elevated IgG1 concentration in the group with other inflammatory diseases. It is concluded that locally synthesized IgG in the cerebrospinal fluids of multiple sclerosis patients consists mainly of IgG1.


Sujet(s)
Immunoglobuline G/liquide cérébrospinal , Sclérose en plaques/immunologie , Humains , Immunoglobuline G/analyse , Sclérose en plaques/liquide cérébrospinal , Maladies du système nerveux/immunologie , Espace sous-arachnoïdien
6.
Clin Chim Acta ; 92(2): 303-5, 1979 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-487580

RÉSUMÉ

A method for the determination of cyclic nucleotide phosphatase (CNP) activity in cerebrospinal fluid is presented. In normal CSF the activity of CNP is very low. Comparing CSF from patients with multiple sclerosis to control CSF no significant difference is found, although a small proportion of MS patients has an elevated has an elevated CNP activity in their CSF. It is postulated that similar to other substances the CNP activity in CSF probably does not derive from the central nervous system.


Sujet(s)
Sclérose en plaques/liquide cérébrospinal , Nucleotidases/liquide cérébrospinal , Système nerveux central/enzymologie , Humains
7.
J Neurol Sci ; 40(2-3): 87-95, 1979 Feb.
Article de Anglais | MEDLINE | ID: mdl-430103

RÉSUMÉ

In normal controls and in a large number of neurological patients divided into certain disease groups both Mg and PO4 were determined in cerebrospinal fluid (CSF) and serum. For both Mg and PO4 there was a marked concentration gradient between CSF and serum in normals where Mg was higher and PO4 content lower in CSF. Comparison of CSF values with serum values of patients showed pathological changes only in CSF, serum values always being within the control range. A number of disease processes associated with a disturbance of blood-brain barrier (BBB) function such as inflammatory CNS disease or CNS tumors showed significant alterations of PO4 concentrations in CSF which are interpreted as an approximation of serum values. A similar decrease of Mg did not reach statistical significance. Both Mg and PO4 in CSF showed a correlation with CSF protein concentrations, but no relationship with cells in CSF. Patients with cerebrosvascular disease were not significantly different from controls as regards their Mg and PO4 in CSF, but a small subgroup consisting of patients with an intracranial hemorrhage showed elevation of both Mg and PO4 which could signify cell necrosis rather than BBB dysfunction. Patients with disc protrusion or peripheral neuropathy did not demonstrate any abnormality of CSF Mg and PO4. In the multiple sclerosis group individual patients had elevated CSF concentrations of PO4 but the group as a whole is not different from the controls.


Sujet(s)
Barrière hémato-encéphalique , Magnésium/liquide cérébrospinal , Maladies du système nerveux/liquide cérébrospinal , Phosphates/liquide cérébrospinal , Hémorragie cérébrale/liquide cérébrospinal , Protéines du liquide céphalorachidien/analyse , Angiopathies intracrâniennes/liquide cérébrospinal , Humains , Inflammation/liquide cérébrospinal , Sclérose en plaques/liquide cérébrospinal , Nécrose/liquide cérébrospinal , Tumeurs/liquide cérébrospinal
8.
Acta Neurol Scand ; 60(5): 277-82, 1979.
Article de Anglais | MEDLINE | ID: mdl-120670

RÉSUMÉ

IgG subgroups (IgG1, IgG2, IgG3, IgG4) were determined by radioimmunoassay (RIA) in cerebrospinal fluid (CSF) of controls, multiple sclerosis (MS), infectious diseases (ID) and other neurological diseases (OND). The proportion of IgG1 in the total IgG subgroup concentration was significantly higher in the MS group compared to the other groups while the IgG2 proportion was significantly lower; IgG3 and IgG4 did not show any consistent change. The inverse relationship between IgG1 and IgG2 was similar in all diagnostic groups: high concentration of IgG1 was associated with low concentrations of IgG2 and vice versa. Patients with a high relative concentration of IgG1 in their CSF have a seven to eight times higher statistical risk to be suffering from MS than ID or OND. In the MS group only the IgG1 concentration correlated with the total IgG concentration determined by radial immunodiffusion, while in controls, ID and OND each IgG subgroup correlated significantly with the IgG concentration. This demonstrates that in MS a selective increase of IgG1 subgroup is mainly responsible for the increase of total IgG, while all subgroups are involved in OND and ID showing an increased total IgG concentration.


Sujet(s)
Immunoglobuline G/liquide cérébrospinal , Sclérose en plaques/immunologie , Albumines/liquide cérébrospinal , Encéphalopathies/liquide cérébrospinal , Encéphalopathies/immunologie , Protéines du liquide céphalorachidien/analyse , Encéphalite/liquide cérébrospinal , Encéphalite/immunologie , Humains , Immunodiffusion , Méningite/liquide cérébrospinal , Méningite/immunologie , Sclérose en plaques/liquide cérébrospinal , Myélite transverse/liquide cérébrospinal , Myélite transverse/immunologie , Dosage radioimmunologique
10.
Ann Neurol ; 3(6): 509-12, 1978 Jun.
Article de Anglais | MEDLINE | ID: mdl-98101

RÉSUMÉ

The immunoglobulin light chain (types kappa and lambda) content of normal cerebrospinal fluid is similar to that of normal serum. In inflammatory diseases of the central nervous system a shift in the k/l ratio in comparison to serum values, usually a relative increase of Igk, can be observed. This increase of the k/l ratio, though not specific for any disease, is most commonly found in multiple sclerosis. There is no correlation between the IgG content and the k/l ratio. The methods described here measure bound and free light chains simultaneously. The calculations show that free light chains are present in both normal and inflammatory CSF and that they appear to be of polyclonal origin. The detection of light chain abnormalities in CSF can be taken as an indicator of endogenous immunoglobulin production in the CNS and is of significance for the diagnosis of inflammatory CNS processes, especially when other signs of endogenous immunoglobulin production are absent.


Sujet(s)
Chaines légères des immunoglobulines/liquide cérébrospinal , Maladies du système nerveux central/liquide cérébrospinal , Humains , Chaines légères kappa des immunoglobulines/liquide cérébrospinal , Chaines lambda des immunoglobulines/liquide cérébrospinal
11.
Acta Neurol Scand ; 57(5): 385-95, 1978 May.
Article de Anglais | MEDLINE | ID: mdl-97915

RÉSUMÉ

Using antisera against Bence-Jones protein, the concentration of light chains type k and l can be determined in CSF. The calculation of the ratio of type k to type I light chains in CSF represents a sensitive measure for the evaluation of immunological processes involving the CNS. Our results demonstrate that an increase k/l ratio is encountered in 48% of CSF specimen from multiple sclerosis (MS) patients, but also in 50% from patients with other inflammatory diseases involving the CNS, in contrast to only 18% from other neurological diseases. In none of the MS or inflammatory cases is the altered k/l ratio the only indicator of a CNS inflammation, most commonly it is accompanied by an overproportional CSF-IgG elevation (increased QG ratio), an increased cell count or both. For these reasons determination of CSF k/l ratios is helpful in the differentiation of MS and other neurological diseases, but not for the differentiation of other inflammatory CNS diseases from MS.


Sujet(s)
Chaines légères des immunoglobulines/liquide cérébrospinal , Chaines légères kappa des immunoglobulines/liquide cérébrospinal , Chaines lambda des immunoglobulines/liquide cérébrospinal , Sclérose en plaques/liquide cérébrospinal , Maladies du système nerveux central/liquide cérébrospinal , Maladies du système nerveux central/immunologie , Humains , Sclérose en plaques/immunologie , Maladies du système nerveux/liquide cérébrospinal
13.
Acta Neurol Scand ; 56(6): 475-82, 1977 Dec.
Article de Anglais | MEDLINE | ID: mdl-605772

RÉSUMÉ

Inflammatory reactions of the central nervous system (CNS) are diagnosed by the determination of elevated immunoglobulin concentrations in cerebrospinal fluid (CSF) due to local production of immunoglobulins. However, unspecific disturbances of the blood-brain-barrier (BBB) can also cause an increase of CSF immunoglobulin concentration as a result of filtration from blood serum. The methods described here attempt a more precise characterization of immunoglobulins in CSF and to define that portion of CSF immunoglobulin derived from the CNS. Albumin and the immunoglobulin fractions IgG, IgA and IgM are determined in serum and CSF. The ratio of albumin in serum and CSF is taken as an indicator of BBB function. By the determination of quotients an overproportional immunoglobulin elevation in CSF as expression of an inflammatory reaction of the CNS can be detected. Methodological problems and the definition of normal ranges are discussed.


Sujet(s)
Barrière hémato-encéphalique , Maladies du système nerveux central/diagnostic , Immunoglobulines/liquide cérébrospinal , Albumines/liquide cérébrospinal , Maladies du système nerveux central/liquide cérébrospinal , Maladies du système nerveux central/immunologie , Humains , Immunoglobuline A/liquide cérébrospinal , Immunoglobuline G/liquide cérébrospinal , Immunoglobuline M/liquide cérébrospinal , Immunoglobulines/analyse , Sérumalbumine/analyse
15.
J Neurol ; 216(1): 47-50, 1977 Aug 18.
Article de Anglais | MEDLINE | ID: mdl-72793

RÉSUMÉ

The serological responses of 195 multiple sclerosis (MS) patients and 251 controls were tested against 6/94-parainfluenza virus, which was previously isolated from brain tissue of two patients with MS. The hemagglutination-inhibition titers of greater than or equal to 1: 128 were found more frequently in MS patients (21.5%) than in controls (14.0%). However, the geometric mean titers did not differ between these two groups. The present study concludes that a causal relationship of 6/94-virus to MS, based on a specific immune response, is improbable, although it does not exclude the possibility of a pathogenetic significance of the agent in the cases from which the autopsy material was derived.


Sujet(s)
Anticorps antiviraux , Sclérose en plaques/immunologie , Respirovirus/immunologie , Adulte , Facteurs âges , Femelle , Humains , Mâle , Adulte d'âge moyen , Facteurs sexuels
16.
Clin Chim Acta ; 78(2): 343-9, 1977 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-69509

RÉSUMÉ

A method for the measurement of light-chain determined immunoglobulin concentrations (Ig-type kappa and Ig-type lambda) in serum is described. The method is based on the principle of radial immunodiffusion. The results obtained after calibration with standarized human serum and with isolated Bence-Jones protein are closely correlated. The values for Ig-type kappa, Ig-type lambda and the kappa/lambda ratio from sera with normal concentrations of IgG, IgA and IgM are presented and some problems of calibration discussed.


Sujet(s)
Épitopes , Chaines légères des immunoglobulines/analyse , Chaines légères kappa des immunoglobulines/analyse , Chaines lambda des immunoglobulines/analyse , Immunoglobulines/analyse , Adolescent , Adulte , Protéine de Bence Jones/analyse , Humains , Immunodiffusion , Immunoglobuline A/analyse , Immunoglobuline G/analyse , Immunoglobuline M/analyse , Adulte d'âge moyen
17.
Clin Chim Acta ; 77(3): 307-16, 1977 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-872431

RÉSUMÉ

A simple and rapid gas chromatographic method for the simultaneous estimation of the anticonvulsant drugs ethosuximide, carbamazepine, phenobarbital, primidone, diphenylhydantoin and the metabolite PEMA in serum is presented. The method is based on a simple ether extraction of 1 ml serum before and after precipitation of the proteins by ammonium sulfate and injection of the extract dissolved in methanol without derivative formation. Gas chromatographic separation is performed on a highly polar acidic phase (SP 1000, a terephthalic acid modified Carbowax 20 M), for detection the instrument is equipped with a nitrogen selective detector, quantitation is performed by automatic electronic integration of peak areas in relation to the internal standard Mesantoin. The optimal approach to the gas chromatographic analysis of "problem drugs" like carbamazepine and phenobarbital is discussed, various stationary phases and support materials are compared for effectiveness with this method. In the analysis of over 800 routine serum samples as well as internal and external quality control samples this method was found to be reliable and the results reproducible.


Sujet(s)
Anticonvulsivants/sang , Carbamazépine/sang , Chromatographie en phase gazeuse , Éthosuximide/sang , Études d'évaluation comme sujet , Humains , Méthodes , Phénobarbital/sang , 2-Éthyl-2-phényl-malonamide/sang , Phénytoïne/sang , Primidone/sang
18.
J Neurol ; 214(3): 207-15, 1977 Feb 17.
Article de Anglais | MEDLINE | ID: mdl-65455

RÉSUMÉ

The leucocyte count, total protein, albumin, IgG, IgA and IgM content of the cerebrospinal fluid (CSF) of 103 multiple sclerosis (MS) patients was determined. In 54 cases a simultaneous analysis of serum was also carried out. As a sign of an intact blood brain barrier the albumin concentration was normal in 76.7%. Taking into account the relative IgG quotient in CSF and serum, and the albumin and IgG concentration gradients between CSF and serum, it was possible to reveal an elevation of IgG content in CSF of MS patients in 75 and 83%, respectively. Without a simultaneous analysis of serum this was the case only in 51.5%. In MS cases with an intact blood brain barrier the values for IgA and/or IgM were slightly elevated in 11.7%. This study demonstrates analytic methods, which support the hypothesis of IgG synthesis by cells accumulating within the CNS in MS. A correlation of the laboratory results and clinical manifestation of MS was tried.


Sujet(s)
Barrière hémato-encéphalique , Protéines du liquide céphalorachidien/analyse , Sclérose en plaques/liquide cérébrospinal , Adulte , Albumines/liquide cérébrospinal , Liquide cérébrospinal/cytologie , Femelle , Humains , Immunoglobuline A/liquide cérébrospinal , Immunoglobuline G/liquide cérébrospinal , Immunoglobuline M/liquide cérébrospinal , Numération des leucocytes , Mâle
19.
J Clin Chem Clin Biochem ; 14(4): 177-80, 1976 Apr.
Article de Allemand | MEDLINE | ID: mdl-818337

RÉSUMÉ

After the tenfold concentration of 1:100 diluted standard solutions in the Minicon B-15 concentrator, the quantitative determination of total protein and of ten single proteins showed a decreased yield. These losses are not standardizable. The reason is analyzed and discussed. Therefore, the quantitative estimation of single proteins by means of immunochemical methods as well as the densitometry of electrophoreses of dilute protein solutions following concentration should be interpreted with caution, because changes in the absolute and relative concentration of proteins are to be expected. These methods are not suitable for exact measurements. An unstandardizable correction coefficient ought to be considered.


Sujet(s)
Protéines/analyse , Réaction Biuret/méthodes , Liquides biologiques/analyse , Filtration/instrumentation , Humains , Immunodiffusion/méthodes , Membrane artificielle , Protéines/isolement et purification , Solutions
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