Search Results - (Author, Cooperation:C. Anders)

article

2003

Erhebung ; Fragebogen ; Interview ; Lernerfolg ; Experiment ; Chemie

International journal of science education, Bd. 25 (2003) H. 3, S. 351-372, 0950-0693

English

2014-02-08

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Actinomyces/*enzymology ; Amino Acid Sequence ; Bacterial Proteins/*chemistry ; Caspase 9/*chemistry ; Crystallography, X-Ray ; DNA Cleavage ; Molecular Sequence Data ; Nucleic Acid Conformation ; Protein Structure, Secondary ; Protein Structure, Tertiary ; RNA/*chemistry ; Streptococcus pyogenes/*enzymology

2014-08-01

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Arginine/genetics/metabolism ; *Base Pairing ; Base Sequence ; CRISPR-Associated Proteins/*metabolism ; Crystallography, X-Ray ; DNA/*chemistry/genetics/*metabolism ; Endonucleases/*metabolism ; Models, Molecular ; Nucleic Acid Denaturation ; *Nucleotide Motifs ; Protein Conformation ; RNA, Guide/chemistry/genetics/metabolism ; Streptococcus pyogenes/*enzymology ; Substrate Specificity

1600-0714

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

At the faculties of dentistry in Chiang Mai, Thailand (CM), and Kuala Lumpur, Malaysia (KL), 234 and 233 consecutive out-patients were interviewed concerning tobacco and chewing habits and examined for the presence of oral melanin pigmentation. Tobacco was regularly used by 32% and 28% of the studied populations in CM and KL. Cigarette smoking was the predominant habit, but the chewing of betel and tea leaves (miang) and the smoking of banana leaf cigars (khi yo) was also registered. The genetically acquired pigmentation dominated. Although nearly all non-tobacco users in the Malay and Indian populations had oral melanin pigmentation, it was found that tobacco smokers had significantly more oral surfaces pigmented than non-tobacco users. Among Thais, the percentage of pigmented individuals was significantly higher among tobacco smokers. It was concluded that tobacco smoking stimulates oral melanocytes to a higher melanin production also in dark-skinned ethnic groups.

Electronic Resource

0009-2614

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Physics

Electronic Resource

1433-0466

Key words Muscle fatigue • Muscle coordination • Isotonic extension loading ; Schlüsselwörter Muskelermüdung • Muskelkoordination • Isotonische Extensionsbelastung

Springer Online Journal Archives 1860-2000

Medicine

Zusammenfassung Während submaximaler isotonischer Extensionsbelastung (31 männliche Personen) wurde eine Oberflächen-EMG-Untersuchung mit 16 monopolar verschalteten Elektroden im unteren Rückenbereich durchgeführt (L 3–S 1). Anhand der Veränderung von Amplituden- und Frequenzparametern im EMG-Signal wurden 2 Personengruppen (je 6 Personen) mit der geringsten bzw. stärksten Muskelermüdung in der paraspinalen Region definiert. Für die Analyse der Muskelkoordination wurde das EMG-Signal mittels einer Amplitudenschätzung zu Beginn und am Ende der Belastungssituation verglichen. Die wenig ermüdenden Personen zeigten innerhalb der Extensionsphase am Ende der Untersuchung keine anderen räumlichen Aktivierungsvorgänge als zu Beginn. Im Gegensatz dazu änderte sich das Aktivierungsmuster während des Tests in der Gruppe stark ermüdender Personen. Deswegen sollte bei der Beurteilung der Wirbelsäulenfunktion zusätzlich zur muskulären Ermüdung auch ein eintretender muskulärer Koordinationsverlust berücksichtigt werden.

Summary During submaximal isotonic back extension loading (31 male persons) surface-EMG was measured using 16 monopolar-linked electrodes in the low back region (L 3–S 1). By means of modification of amplitude- and frequency parameters in the EMG-signal two subject groups (6 persons each) with the slightest and most severe muscle fatigue in the paraspinal region were defined. For the analysis of muscle coordination, the EMG signal on the basis of an amplitude estimate at the beginning and at the end of the load situation was compared. During the extension phase, the group with slight fatigability showed no different spatial pattern of myoelectrical activity at the end of investigation than at the beginning. In contrast to this, the pattern of myoelectrical activity changed during the endurance test in the group of persons with considerable fatigability. Therefore, in addition to the muscular fatigue also the loss of muscle coordination has to be taken into account in the assessment of spinal function.

Electronic Resource

1432-8798

Springer Online Journal Archives 1860-2000

Medicine

Summary The genomic relationship of porcine hemagglutinating encephalomyelitis virus (HEV) to bovine coronavirus (BCV) and human coronavirus (HCV) strain OC43 was examined by dot blot hybridization assays. Two BCV S gene-specific probes were generated by polymerase chain reaction from the avirulent L9-strain of BCV. Probes were located in the S1 and the S2 region of the peplomeric (S) glycoprotein gene. The S1 probe (726 bp) hybridized with BCV and HCV-OC43, but not with HEV under moderate stringency hybridization conditions (50 °C). Only slight signals were present with mouse hepatitis virus (MHV) and no signals were observed with feline infectious peritonitis virus (FIPV) or canine coronavirus (CCV). At high stringency conditions (60 °C) the S1 probe hybridized with BCV only. Using the S2 probe (680 bp) under moderate strin-gency conditions, hybridization signals were obtained with BCV, HCV-OC43 and HEV (strains 67N, NT9, VW572). The signals obtained by the three HEV strains were altogether weaker than with BCV and HCV-OC43. The S2 probe did not react with MHV, FIPV and CCV. At high stringency the S2-specific probe hybridized with BCV and HCV-OC43 but did not hybridize with HEV. Nucleotide sequence analysis of the region covering the S2 probe in HEV revealed 92.6% nucleotide sequence homology to BCV and 91.9% to HCV-OC43. In contrast, the region covering the S1 probe in HEV could not be amplified using the BCV S1-specific primers. The hybridization and sequencing results thus indicate a closer genomic relationship between BCV and HCV-OC43 than there is between HEV and BCV or HCV-OC43, respectively.

Electronic Resource

1573-4838

Springer Online Journal Archives 1860-2000

Medicine

Technology

Abstract As a model for hydrogel-coated biomaterials, self-assembled monolayers of polyoxyethylene (POE) derivatives on sheets of polymeric biomaterials were prepared. The POE derivatives consisted of hydrophilic chains with different lengths and a long-chain alkyl group that served as an anchor function. The coatings obtained were analyzed with XPS and contact angle measurements showing hydrophilic chains of different lengths extending away from the surface. Bacterial adhesion was measured with a clinically relevant Klebsiella pneumoniae type strain and measurements reproduced 12 times. Bacterial adhesion decreased markedly with increasing hydrophilic chain length. Based upon these findings a new model for bacterial adhesion to hydrogel-coated surfaces is suggested: steric repulsion effects that increase with increasing chain length of grafted hydrophilic chains play an important role in bacterial adhesion to hydrogel-coated surfaces. © 1999 Kluwer Academic Publishers

Electronic Resource

1432-2013

Inspiratory neurones ; Slowly adapting pulmonary stretch receptors ; Spike triggered averaging ; Neural control of respiration ; Connectivity of respiratory neurones ; Nuclei of the tractus solitarius ; Hering-Breuer reflex

Springer Online Journal Archives 1860-2000

Medicine

Abstract The synaptic connection between slowly adapting pulmonary stretch receptor afferents and inspiratory neurones within a region ventral to the tractus solitarius was determined using intracellular recording and spike triggered averaging techniques. When the vagus nerve was stimulated at intensities eliciting a Hering-Breuer reflex, the difference in mean latency between centrally recorded action potentials of slowly adapting pulmonary stretch receptor afferents and e.p.s.p.s of inspiratory beta neurones was 0.2 ms. This difference is indicative of a monosynaptic connection. Extracellular single unit spikes of slowly adapting pulmonary stretch receptors recorded from the nodose ganglion were used to trigger the averaging of synaptic noise recorded from inspiratory neurones. A prominent wave of synaptic depolarization was observed in all inspiratory beta neurones even when a small number of sweeps were averaged. This depolarization was absent from inspiratory alpha neurones. The shape indices of these depolarizations are consistent with a monosynaptic connection between slowly adapting pulmonary stretch receptor afferents and inspiratory beta neurones. In addition, the data raise the possibility that this connection is multiple and distributed.

Electronic Resource