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11.
Antiserum was made against a single 30S protein, 30S-7. The amount of complement fixed by total 30S protein in the presence of this antiserum indicated that protein 30S-7 was the major antigen in the mixture of proteins. Each of the 30S ribosomal proteins was tested for cross-reactivity with anti-30S-7. This was done by determining if any of the other 30S proteins inhibited complement fixation by 30S-7. None of the other 30S proteins was found to inhibit complement fixation by 30S-7, indicating that 30S-7 is antigenically distinct from the other proteins. 相似文献
12.
Each major component of the proteins of 30S ribosomes from Escherichia coli was compared with the proteins of 50S ribosomes. The comparisons were done by using polyacrylamide gel electrophoresis in urea with differentially labeled proteins. The data show that no major protein is common to both ribosomes. 相似文献
13.
For the first time a complete ostracode and trilobite fauna is described from the Dobrovitá Formation (Ordovician) of Perunica. In contrast to the trilobite fauna the ostracode fauna evidences close relations to both Armorica and Baltica. The trilobite fauna comprises 11 species out of 11 genera, the ostracode fauna comprises 15 (5 new) species out of 15 (1 new) genera. 相似文献
14.
Jan Nešvera Jitka Hochmannová Miroslav Pátek Alena Šroglová Věra Bečvářová 《Applied microbiology and biotechnology》1994,40(6):864-866
Gram-positive facultative methylotrophic coryneform bacterium Brevibacterium methylicum was efficiently transformed with various plasmids using electroporation of intact cells. In addition to the plasmid vectors pEC71 and pZ6-1 constructed on the basis of cryptic plasmids from coryneform bacteria, broad-host-range plasmids pLS5 (derivative of plasmid pMV158 from Streptococcus agalactiae) and RSF1010 belonging to the incompatibility group IncQ from Gram-negative bacteria were found to be present as autonomous structurally unchanged DNA molecules in B. methylicum transformants. With the exception of pZ6-1, all these plasmids were stably maintained in B. methylicum cells grown under non-selective conditions. When plasmid DNAs isolated from B. methylicum were used, the highest efficiency of transformation (105 transformants/g DNA) was achieved.
Correspondence to: J. Nevera 相似文献
15.
Pavol Mrtonfi Anton Grejtovský Miroslav Rep
k 《Biochemical Systematics and Ecology》1994,22(8):819-825
Relationships between soil chemistry and population chemotype structure of Thymus pulegioides have been studied. The analysis of correlations suggest that an increased carbonate content in soil decreases the chemotype diversity of a population (as calculated by use of the Shannon index): the proportion of linalool chemotype plants rises and that of the phenol chemotype plants declines. In addition, the chemotype diversity decreases with increasing frequency of linalool chemotype, and increases with increase of carvacrol chemotype. 相似文献
16.
A new covalently-bonded, silica-based stationary phase, using as the chiral selector the 1-(3-aminopropyl) derivative of (+)-(5R,8S,10R)-terguride, has been developed to resolve optically active isomers by HPLC. Good resolution of structurally related racemic ergot alkaloids were obtained using water-methanol mixtures as the eluent. Analysis of the influence of the type and concentration of the organic modifier, and the pH of the buffer in the mobile phase allowed the enantioseparation of these compounds to be optimized. Determination of the optical purity of a lisuride-containig drug is reported. © 1994 Wiley-Liss, Inc. 相似文献
17.
C. David Pauza Peter Emau Maria S. Salvato Parul Trivedi Debra MacKenzie Miroslav Malkovsky Hideo Uno Kevin T. Schultz 《Journal of medical primatology》1993,22(2-3):154-161
Intrarectal inoculation of rhesus monkeys with low doses of SIVmac led to a prolonged clinical and virological latency that was not observed for high intrarectal doses or for intravenous inoculation. Animals infected intrarectally with low virus doses remained negative for serum antibody responses to SIV for at least one year even though they readily transferred SIV to naive recipients via transfusion of whole blood. 相似文献
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Jan Tumajer Krešimir Begović Vojtěch Čada Michal Jenicek Jelena Lange Jiří Mašek Ryszard J. Kaczka Miloš Rydval Miroslav Svoboda Lukáš Vlček Václav Treml 《Global Change Biology》2023,29(2):462-476
Radial tree growth is sensitive to environmental conditions, making observed growth increments an important indicator of climate change effects on forest growth. However, unprecedented climate variability could lead to non-stationarity, that is, a decoupling of tree growth responses from climate over time, potentially inducing biases in climate reconstructions and forest growth projections. Little is known about whether and to what extent environmental conditions, species, and model type and resolution affect the occurrence and magnitude of non-stationarity. To systematically assess potential drivers of non-stationarity, we compiled tree-ring width chronologies of two conifer species, Picea abies and Pinus sylvestris, distributed across cold, dry, and mixed climates. We analyzed 147 sites across the Europe including the distribution margins of these species as well as moderate sites. We calibrated four numerical models (linear vs. non-linear, daily vs. monthly resolution) to simulate growth chronologies based on temperature and soil moisture data. Climate–growth models were tested in independent verification periods to quantify their non-stationarity, which was assessed based on bootstrapped transfer function stability tests. The degree of non-stationarity varied between species, site climatic conditions, and models. Chronologies of P. sylvestris showed stronger non-stationarity compared with Picea abies stands with a high degree of stationarity. Sites with mixed climatic signals were most affected by non-stationarity compared with sites sampled at cold and dry species distribution margins. Moreover, linear models with daily resolution exhibited greater non-stationarity compared with monthly-resolved non-linear models. We conclude that non-stationarity in climate–growth responses is a multifactorial phenomenon driven by the interaction of site climatic conditions, tree species, and methodological features of the modeling approach. Given the existence of multiple drivers and the frequent occurrence of non-stationarity, we recommend that temporal non-stationarity rather than stationarity should be considered as the baseline model of climate–growth response for temperate forests. 相似文献