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131.
Modulation of the immunologic response to acute stress in humans by beta-blockade or benzodiazepines
RJ Benschop R Jacobs B Sommer TH Schürmeyer JR Raab RE Schmidt M Schedlowski 《Canadian Metallurgical Quarterly》1996,10(4):517-524
Autoantibodies against heat shock protein (hsp) 60 have been reported to be detected in sera of non-obese diabetic mice, in an experimental model of IDDM. However, there are only a few studies which have examined IDDM patients for antibodies against mammalian hsp60. We produced murine hsp60 derived from pancreatic beta cells which has high homology to human hsp60 and examined antibodies against the hsp60 in IDDM patients using an enzyme-linked immunosorbent assay. We extended the analysis to patients with other immune-mediated diseases and non-insulin-dependent diabetes mellitus (NIDDM). Positive sera for hsp60 antibody were more frequently detected in 13 out of 84 IDDM (15.5%) and 5 out of 25 rheumatoid arthritis patients (20%), when compared to healthy subjects (1/85; 1.2%, P < 0.001 and P < 0.01, respectively). The levels of hsp60 antibodies of IDDM (0.218 +/- 0.227) and rheumatoid arthritis patients (0.259 +/- 0.191) were significantly higher than those of healthy subjects (0.076 +/- 0.131, P < 0.001, P < 0.01, respectively). Patients with slowly progressive IDDM (n = 26), autoimmune thyroid disease (n = 42), or NIDDM (n = 40) had levels of hsp60 antibodies similar to those in healthy subjects. We found no relationship between the levels of hsp60 antibodies and islet cell antibodies (ICA) or antibodies to glutamic acid decarboxylase (GAD65) in IDDM patients. In conclusion, hsp60 antibodies were detected in Japanese IDDM as well as in rheumatoid arthritis patients. Although the positivity was low, the detection of hsp60 antibodies may be helpful for diagnosis of IDDM especially in GAD65 Ab- or JCA-negative Japanese patients. 相似文献
132.
133.
A new method is proposed to evaluate the source resistance RS directly from the S-parameters of a field-effect transistor biased in the active region. The method is based on the fact that the real part of the feedback admittance is mainly caused by the source and the gate resistance. This enables the analytical calculation of RS at any measured frequency with high accuracy. Taking the ratio of RG with regard to RS as the only optimizing parameter, it is possible to calculate quickly an equivalent circuit the elements of which do not depend on starting values. The equivalent circuit fits the measured S-parameters very well and allows a physical interpretation of the calculated elements. By application of the new method in accordance with theoretical considerations one can observe for the first time from RF-measurements a bias-dependence of the source resistance that has been assumed to be constant up to now 相似文献
134.
Veronika Strehmel Kerstin Fryauf Claudia Sommer Karl-Friedrich Arndt Manfred Fedtke 《大分子材料与工程》1992,196(1):195-206
The network formation process of bisphenol A-diglycidylether and 4,4′-diaminodiphenylmethane was investigated by measuring the torque, the conductivity and the soluble part of the crosslinking system. The activation energy for the curing process was estimated from gel time. The volume shrinkage during network formation was measured. The influence of N,N-dimethylbenzylamine as accelerator was discussed. 相似文献
135.
136.
A method für the determination of N-nitrosoalkanolamines in cosmetics and toiletries is described. The ingredients used in their manufacture N-nitroso-bis-(2-hydroxyethyl)amine (N-nitrosodiethanolamine, NDELA) and N-nitroso-bis-(2-hydroxy-propyl)amine (NBHPA) are almost exclusively the contaminants. The method has therefore been modified for their determination. N-Nitroso-(2-hydroxy-ethyl)-(2-hydroxypropyl)amine is used as the internal standard. After dilution with water, the cosmetic is adsorbed onto a kieselguhr column and extracted with n-butanol. The extract is brought to dryness, re-dissolved in chloroform/acetone (5 + 1) and transferred to a silica gel column. The column is washed and eluted with acetone. The eluate is dried and the residue is treated with N-methyl-N-trimethylsilyl-heptafluorobutyramide. Trimethylsilyl (TMS)derivatives of N-nitrosoalkanolamines are determined by gas-chromatography with a thermal energy analyzer (TEA). Recovery of the internal standard is 95% and the determination limit is 5 micrograms/kg, Repeated analyses of a foam bath, spiked with 30 micrograms/kg NDELA, gave an average content of 32 micrograms/kg NDELA (variation coefficient 8.8%; n = 10). In order to avoid artefact formation during the clean-up process, kieselguhr containing 50% sodium ascorbate has to be used when cosmetics containing free dialkanolamines are analyzed. 相似文献
137.
138.
A Hartmann H Blaszyk JS Cunningham RM McGovern JS Schroeder SD Helander MR Pittelkow SS Sommer JS Kovach 《Canadian Metallurgical Quarterly》1996,67(3):313-317
Heterocypris incongruens (RAMD.) was selected as an intermediate host, having emerged as the main host for Diorchis stefanskii Czapl. in experimental conditions. It was found that the index of infective activity for larvae of D. stefanskii was high on the first day, amounting to 50-54%, with an extensity of infection of 100%. The infective activity of larvae declined slowly but steadily at the low temperature (5 degrees C). Oncospheres retained their infective activity for more than 2.5 months. In contrast, in culture at 18-20 degrees C and 25 degrees C, the infective activity of larvae had declined rapidly only a few days into the experiment. The irrevocable loss of tapeworm infectivity occurred at temperatures of -5 degrees C and +38 degrees C, at which 100% of oncospheres died. 相似文献
139.
Laser energy densities of less than 1 J/cm2 had no apparent effect on human tissues, while energy densities of more than 4 J/cm2 resulted in tissue damage. For non-punctiform laser applications, therefore, a laser beam distribution system that provides a homogeneous energy density distribution is of advantage, since such a system permits safe application of the laser in the effective therapeutic range. Conventional laser scanners for medical use have been reported to produce grossly inhomogeneous energy density distributions. The new LILAB system, which is a very fast laser beam distribution system, readily generates application fields of different configuration with high homogeneous energy density distribution. The article presents an example of a randomly selected application field, in which the energy densities at the edges and at the centre are compared. 相似文献
140.