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41.
Volker Hofmann Helmut Ringsdorf Erich Schaumlffel 《Macromolecular chemistry and physics.》1980,181(2):351-366
Poly[2-(methylsulfinyl)ethyl acrylate] ( 1 ) was synthesized as well as derivatives 14C-labelled in side groups ( 6 ) or 14C-labelled in the main chain ( 11 ). Polymer 11 with the 14C-labelled main chain was fractionated by precipitation. The η-M-relation determined by measurements of unlabelled polymers in the ultracentrifuge for comparison was used to establish the viscosimetrically determined molecular weights of the labelled fractions. After intravenous application of aqueous solutions of the polymer in rats the excretion rate up to 72 h after treatment was ascertained to ca. 50%; the concentration in the blood serum was found to be strikingly high. A tendency to reinforced storage in organs of high phagocytose activity by growing molecular weight was observed. The tumor affinity was — if at all — low. 相似文献
42.
Antibody to Mycoplasma pneumoniae in Nasal Secretions and Sputa of Experimentally Infected Human Volunteers 总被引:8,自引:7,他引:8 下载免费PDF全文
Helmut Brunner Harry B. Greenberg Walter D. James Robert L. Horswood Robert B. Couch Robert M. Chanock 《Infection and immunity》1973,8(4):612-620
After experimental infection with Mycoplasma pneumoniae, 42% of 67 volunteers developed a threefold or greater rise in antibody in nasal secretions as measured by radioimmunoprecipitation. Development of an antibody increase in sputum was detected more often, i.e., in 73% of the volunteers. Each of the antibody increases involved immunoglobulin (Ig) A. Twelve rises in IgG antibody were detected in the specimens which exhibited a rise in IgA antibody. In almost every instance the rise in IgA antibody exceeded that seen with IgG antibody. Analysis of the response to experimental challenge with M. pneumoniae of volunteers with different levels of preexisting respiratory tract IgA antibody suggested that this secretory antibody was related to host resistance to M. pneumoniae disease. Further, respiratory tract IgA antibody appeared to be more directly related to host resistance than was antibody in serum. 相似文献
43.
Dr. med. Gerhard Mall Helmut Reinhard Doris Stopp Johannes Albrecht Rossner 《Virchows Archiv : an international journal of pathology》1980,385(2):169-180
Summary Male Wistar rats were treated with high cortisol doses for 1 week. The dose administered daily was 15 mg per animal in group 1 (7 animals) and 30 mg in group 2 (7 animals). 7 rats served as control group. After cortisol treatment the body weights decreased due to skeletal muscle catabolism and the heart weights increased. Morphometric analysis of the left ventricular posterior papillary muscles gave evidence that the increased heart weights resulted from an increased number of mitochondria and an increased volume of the cytoplasm, whereas the myofibrillar mass was not affected. The surface area of inner mitochondrial membranes (+cristae mitochondriales) per myofibrillar unit volume increased from 15.7 2/3 to 21.3 2/3 in group 1 and 21.4 2/3 in group 2. Ultrastructural changes indicating myocardial cell damage were absent. Similar quantitative results have been reported to occur in the early phase of cardiac overload. For elucidating the hemodynamic effects of glucocorticoid a second experiment was performed: 7 Wistar rats were treated with cortisol in the same way as group 1, 7 others of the same body weight served as control. The systolic arterial pressure was significantly elevated in the cortisol group. Though myocardial tissue is known to be able to accumulate large quantities of glucocorticoids our results indicate that the application of high cortisol doses for a short time does not produce myocardial cell damage and does not suppress the myocardial adaption to the glucocorticoid-induced hypertension, i.e. hypertrophy. On the contrary, it seems to be possible that the adaption process is itself facilitated or accelerated by the presence of high cortisol concentrations in the heart. This thesis is supported by the considerably higher relative heart weights in the cortisol groups and is in agreement with observations reported by other authors.Dedicated to Professor Dr. W. Doerr on the occasion of his 65th birthdayThe results have been partially reported in 1977 (cf. G. Mall and H. Reinhard, Verh. Dtsch. Ges. Path. 61, 445)This investigation was supported by the Sonderforschungsbereich 90 of the Deutsche Forschungsgemeinschaft. 相似文献
44.
Drell A. Bottorff Sukran Parmaksizoglu Edmond G. Lemire John W. Coffin Helmut Bertrand Frank E. Nargang 《Current genetics》1994,26(4):329-335
The cyt-12-12 mutant of Neurospora crassa is characterized by slow growth and a deficiency of spectrophotometrically-detectable cytochromes aa
3
and c. Using a sib-selection procedure we have isolated the cyt-12
+
allele from a cosmid library of N. crassa genomic DNA. Characterization of the cyt-12
+
allele reveals that it encodes the structural gene for cytochrome c. DNA sequence analysis of the cyt-12-12 allele revealed a mutation in the cytochrome c coding sequence that results in replacement of a glycine residue, which is invariant in the cytochrome c of other species, with an aspartic acid. Genetic analysis confirms that cyt-12-12 is allelic with the previously-characterized cyc-1-1 mutant, which was also shown to affect the single locus encoding cytochrome c in N. crassa. We suggest that the amount of functional cytochrome c present in mitochondria influences the level of cytochrome aa
3
. 相似文献
45.
Werner Haas Jacqueline Mathur-Rochat Helmut Pohlit Markus Nabholz Harald Von Boehmer 《European journal of immunology》1980,10(11):828-834
Various procedures were used to derive continuously growing cytotoxic T lymphocyte (CTL) clones from a primary culture containing responder cells from immunized mice and 3-(p-sulfophenyldiazo)-4-hydroxylphenyl acetic acid (SP)-or fluorescein isothiocyanate (FL)-coupled stimulator cells. It seems likely that CTL have to undergo some change, possibly genetic, to be able to grow continuously in T cell growth factor conditioned medium in the absence of any stimulator or filler cells. The most convenient and reliable procedure to generate CTL clones with different specificities was to establish from several aliquots of a primary culture cell populations continuously growing in medium conditioned with T cell growth factor(s). Clones with different specificities segregated in the different populations. SP-and FL-specific CTL clones restricted to H-2Kk, and H-2Dd and two FL-specific CTL clones with no apparent H-2 restriction are described. 相似文献
46.
Ulrike Fuhrmann Karsten Parczyk Michael Klotzbücher Helmut Klocker A. C. B. Cato 《Journal of molecular medicine (Berlin, Germany)》1998,76(7):512-524
Antihormones are by definition antagonists of steroid hormone action. They interact with the ligand binding domains of steroid
hormone receptors and competitively inhibit the action of the receptors by mechanisms that are not quite understood. In certain
cases antihormones also exhibit agonistic activity especially in connection with certain naturally occurring receptor mutants.
These observations together with findings of indiscriminate interaction of antihormones with several classes of steroid receptors
have necessitated a search of more effective and reliable antihormones. Recent advances in the resolution of the crystal structure
of the ligand binding domains of certain members of the steroid receptor family and identification of non-liganded activation
of steroid receptors have produced considerable information that can be harnessed into a fruitful search for a new generation
of antihormones.
Received: 19 June 1997 / Accepted: 10 October 1997 相似文献
47.
11-Methacryloylaminoundecanoic acid ( 1 ) was esterified with the monoalcohols isobutyl alcohol, cyclohexanol, DL -menthol, cholesterol, testosterone and an excess of 12-hydroxylauric acid in the presence of lipase as catalyst. The kinetics of the esterification reactions were followed by 1H NMR spectroscopy and the results were correlated with sterical effects. The monomers were polymerized radically. The monomeric 12-hydroxylauric acid oligoester 11 as well as its homopolymer 12 were characterized by DSC and viscosity measurements. 相似文献
48.
Zusammenfassung Es wird über einen Fall akuter Erythroleukämie mit G-Trisomie berichtet und die mögliche Bedeutung hereditärer Faktoren für die Manifestation akuter Leukämien diskutiert.
Summary The cytogenetic analyses of direct bone marrow preparations in a 53 years old male with acute erythroleukaemia of 9 months disease history, revealed persistently a G-trisomy in a dominant cell line with 47 chromosomes. The peripheral blood culture preparations with phytohaemagglutinin exhibited normal diploid cell line.The frequent occurrence of akute leukaemia in Down's syndrome tempts to implicate that leukaemia with G-Trisomy having no signs of Down's syndrome is a somatic mutation initiated by some unknown hereditary recessive genes mechanisms.相似文献
49.
2-Bromoethoxycarbonyl modified amino acids were reacted with pyridine, 4-picoline and poly(4-vinylpyridine) to yield the corresponding 2-(N-pyridinio)ethoxycarbonyl derivatives as water-soluble amino-protecting groups. The kinetics and activation energies of basicly induced cleavage of the amino acids were investigated by 1H NMR spectroscopy in a D2O/NaOD medium. The polymeric salts were found to be more reactive than the low molecular weight pyridinium bromides because of electrostatic polymeric effects. Additionally, the kinetic measurements confirmed a E1cB mechanism for the cleavage of the urethane function. The formation of peptide bonds was performed in the case of poly[2-(N-4-vinylpyridinioethoxycarbonyl)]-protected amino acids in aqueous medium by water-soluble carbodiimides. 相似文献
50.
P. Gilon Y. Miura J. C. Henquin J. Tytgat P. Daenens V. Decostre G. Maréchal S. M. Brichard D. J. Becker B. Reul L. N. Ongemba V. Rousseau W. Eechaute W. Dhooghe P. Calders N. C. Gao E. Lacroix J. Weyne J. Kaufman S. Tomasovic F. Frankenne A. Boland D. Delapierre D. Marechal A. Dresse O. Feron M. Wibo M. Maleki L. Zheng F. Kolar T. Godfraind K. Paemeleire L. Leybaert C. Lambillotte M. Nenquin E. Wechsung A. Houvenaghel G. Mancuso E. Tirelli S. Vandenput D. Votion D. H. Duvivier T. Art P. Lekeux H. D. Duvivier B. S. Kelemen E. Van Erck I. Mountian L. Missiaen W. Van Driessche 《Pflügers Archiv : European journal of physiology》1996,432(4):R139-R144