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271.
E. Bezzel R. Prinzinger S. Schuster W. Dornberger H. Ringleben und H. -W. Helb 《Journal of Ornithology》1986,127(1):103-115
Ohne Zusammenfassung 相似文献
272.
The antibacterial activity of ten N-alkylated derivatives of daunorubicin and adriamycin as well as of 5-iminodaunorubicin has been tested by using Bacillus subtilis 170, Escherichia coli B, and Proteus mirabilis VI and their stable protoplast type L-forms in an agar diffusion test. Eight of the substances showed similar activities against B. subtilis and the L-forms of all test organisms, but no activity against the bacterial forms of E. coli and P. mirabilis. The cell wall of these gram-negative bacteria is responsible for this resistance by not allowing the antibiotics to enter the cells. The piperidino compound N-(CH2)5 daunorubicin shows 2-4 times higher activity against B. subtilis and all L-forms in comparison to daunorubicin and the other derivatives. Five of the substances were inactive against all test strains. Their inactivity seems to be associated with the larger substituents at the C-3' position. Relations between molecular structure and activity are discussed considering data about the interaction with DNA and the antitumor activity. Stable protoplast type L-forms and their bacterial forms represent a suitable and effective test system to screen for more effective substances and to get more information about their mode of action. 相似文献
273.
Valentina Adami Natalie Homer Nadine Utz Saskia Lippens Joshua Z. Rappoport Julia Fernandez-Rodriguez 《Journal of biomolecular techniques》2021,32(1):1
Core facilities (CFs) provide a centralised access to costly equipment, scientific expertise, experimental design, day-to-day technical support and training of users. CFs have a tremendous impact on research outputs, skills and educational agendas, increasing the competencies of staff, researchers and students. However, the rapid development of new technologies and methodologies for the life sciences requires fast adaptation and development of existing core facilities and their technical and scientific staff. Given the scarcity of well-defined CF career paths, CF staff positions are typically filled by people having followed either academic or technical tracks. Each academic institution follows different policies and often fails to adequately recognize the merits of CF personnel and to support their training efficiently. Thus, the Core Technologies for Life Science association (CTLS), through the Training working group, has conducted an anonymous online survey to assess the training needs of CF personnel, as well as to identify common characteristics and challenges in this relatively new and dynamic career type. 275 individuals, including core managers and directors, technicians, technologists and administrators, participated in the survey. The survey was divided into 2 sections; the first, applied to all respondents, and the second, specifically targeted core management issues. Training needs in technological areas, financial and soft skills, management and administrative issues were surveyed as well. The lack of clarity and consistency regarding established career paths for CF professionals was evident from the second part of the survey, highlighting geographical or cultural differences. Gender balance was achieved and the distribution was always taken into account. The results of this survey highlight a need to develop better training resources for CF staff, to improve their recognition within academic institutions, and to establish a recognized career pathway. 相似文献
274.
A McGrady S W Utz M Woerner G A Bernal J T Higgins 《Biofeedback and self-regulation》1986,11(2):95-103
This paper describes differences in response in seventeen patients with essential hypertension who participated in a treatment program consisting of electromyograph biofeedback assisted relaxation training. Responders were found to have higher treatment values of urinary and plasma cortisol, Trait Anxiety and forehead muscle tension compared to treatment failures. Responders also sustained greater decreases in plasma, and urinary cortisol after treatment. These data are discussed in light of the ability to predict which hypertensive patients may be most benefitted by a relaxation based treatment. 相似文献
275.
U Utz S Koenig J E Coligan W E Biddison 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(1):214-221
To determine whether similar or dissimilar molecular features of class I molecules are involved in the presentation of structurally distinct peptides, we have investigated the influence of different pockets of the HLA-A2.1 molecule on the presentation of three different viral peptides. HTLV-I Tax peptide 12-19, HCMV gB 619-628, and influenza M1 58-66 are minimal peptides that induce HLA-A2.1-restricted noncross-reactive CTL. A detailed analysis of the structural features of HLA-A2.1 that are involved in peptide presentation was undertaken using a panel of 11 HLA-A2 mutants with single amino acid substitutions within pockets present in the peptide binding site. Nine of the 11 mutants affected presentation of each of the three peptides, whereas the other two mutants had negative effects on presentation of only two of these viral peptides. These results indicate that common structural features in HLA-A2 determine the binding of different peptides, and help to provide a plausible explanation for how structurally diverse peptides bind to HLA-A2. 相似文献
276.
J. Dierschke F. Bairlein J. Böhner K. -M. Exo S. Klaus V. Dierschke und W. Dornberger 《Journal of Ornithology》1998,139(2):187-192
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