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71.
This paper raises the general question of whether there are any national peculiarities that characterize the scientific and philosophical roots of Russian-language evolutionary developmental biology. The researchers and theories are surveyed which, with hindsight, have been crucial for the Russian tradition when it comes to general methodological principles and constituting concepts. Based on published works and archival documents the main concepts of the “founding fathers” of the Russian tradition with their “Western analogues” are compared. The focus is on A. O. Kowalevsky (1840–1901), I. I. Metschnikov (1945–1916), A. N. Sewertzoff (1866–1936), I. I. Schmalhausen (1884–1963) and the parallelisms between them and E. Haeckel (1834–1919), V. Franz (1883–1950), and C. H. Waddington (1905–1977). In addition, the problem of specific influences constituting the Russian-language context of the Modern Synthesis is addressed. The major thesis of this paper is that the very character of the Russian developmental biology and its intellectual environment predisposed a strong bias towards environmentalist interpretations and thus anticipated what we now call “ecological developmental biology”. This paper is an extended version of my talk delivered to the First and founding meeting of the European Society for Evolutionary Developmental Biology (EDD), 16–19 August (Prague, Czech Republic). I thank Scott Gilbert for inviting me to this meeting
Georgy S. LevitEmail:
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M N Levit  Y Liu  J B Stock 《Biochemistry》1999,38(20):6651-6658
The chemotaxis receptor for aspartate, Tar, generates responses by regulating the activity of an associated histidine kinase, CheA. Tar is composed of an extracellular sensory domain connected by a transmembrane sequence to a cytoplasmic signaling domain. The cytoplasmic domain fused to a leucine zipper dimerization domain forms soluble active ternary complexes with CheA and an adapter protein, CheW. The kinetics of kinase activity within these complexes compared to CheA alone indicate approximately a 50% decrease in the KM for ATP and a 100-fold increase in the Vmax. A truncated CheA construct that lacks the phosphoaccepting H-domain and the CheY/CheB-binding domain forms an activated ternary complex that is similar to the one formed by the full-length CheA protein. The Vmax of H-domain phosphorylation by this complex is enhanced approximately 60-fold, the KM for ATP decreased to 50%, and the KM for H-domain decreased to 20% of the values obtained with the same CheA construct in the absence of receptor and CheW. The kinetic data support a mechanism of CheA regulation that involves perturbation of an equilibrium between an inactive form where the H-domain is loosely bound and an active form where the H-domain is tightly associated with the CheA active site and properly positioned for phosphotransfer. The data are consistent with an asymmetric mechanism of CheA activation [Levit, M., Liu, I., Surette, M. G., and Stock, J. B. (1996) J. Biol. Chem. 271, 32057-32063] wherein only one phosphoaccepting domain of CheA at a time can interact with an active center within a CheA dimer.  相似文献   
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Adequacy and effectiveness of empirical antibacterial therapy of severe nosocomial infections with meropenem vs. combined regimens of antibacterial therapy were investigated and the ratio of the cost and effectiveness of the compared regimens was evaluated. A prospective, randomized, open, comparative study of two initiative regimens of empirical antibacterial therapy of severe nosocomial infections was performed: meropenem in a daily dose of 1.5-3 g and the standard regimen with the use of betalactams and fluoroquinolones in combination with aminoglycosides and/or metronidazole. Patients with recorded diagnosis of nosocomial pneumonia (including the ventilator-associated one) or abdominal infection with the signs of severe sepsis and severity of APACHE II > 14 were enrolled. The patients were stratified into 2 groups subject to the disease severity, i.e. APACHE II 15-20 and APACHE II 21-25. One hundred thirty five out of 166 patients with recorded nosocomial infection were included into the final estimate of the therapy adequacy and effectiveness (Protocol Analysis): 62 patients were treated with meropenem and in the treatment of 73 patients the standard antibacterial therapy was used. In the group of the patients treated with meropenem there were stated significantly higher clinical effectiveness (recovery in 80.6% of the patients vs. the control of 46.6%, p < 0.01) and pathogen eradication (89.6 and 48.1% respectively, p < 0.01). The difference in the clinical and bacteriological effectiveness of meropenem and the standard therapy was more evident in the subgroups of more severe patients (APACHE > 20). With the use of meropenem the probability of recovery from nosocomial infection was significantly higher (RR 1.73-1.94, p < 0.001) vs. the control. Meropenem provided significantly higher eradication of the pathogens: P. aeruginosa (88 and 40% respectively, p = 0.007), E. coli (100 and 46.7%, p = 0.003), Acinetobacter spp. (90.9 and 40%, p = 0.02). The antibacterial therapy with the use of meropenem was assessed as adequate in 51 out of 56 patients (91.1%), that was 3 times as frequent as with the use of the standard antibacterial therapy (33.9%). The cost-effectiveness coefficient with the use of meropenem was 2.2 times lower vs. the control. Therefore, the empirical therapy of severe nosocomial infections with meropenem proved to be more adequate and from the economic viewpoint more advantageous vs. the standard combined regimens of antibacterial therapy, that was evident from significantly higher clinical and bacteriological efficacy of the treatment and decrease of the terms of the patients hospitalization in intensive care units (on the average by 5 days).  相似文献   
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Principles of detecting organisms producing beta-lactamase inhibitors among soil actinomycetes were developed. For detecting such cultures it was recommended to use the Gauze agarized medium No. 1 supplemented with beta-lactam antibiotics. Benzylpenicillin proved to be the most efficient. Various liquid fermentation media for detecting the inhibitory activity of soil actinomycetes were compared. Two media were the most favourable i.e. the glucose-yeast medium No. 18/3 and the soybean-glucose medium with Na2SO4 and CoCl2 No. 20/3. The use of test cultures with relatively low resistance to benzylpenicillin was shown expedient in screening cultures producing beta-lactamase inhibitors. Test cultures with high resistance should be used in more detailed characterization of the selected cultures.  相似文献   
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In the arms race between avian brood parasites and their hosts, several adaptations and counter‐adaptations have evolved. The most prominent host defence is rejection of parasitic eggs. We experimentally parasitized nests of 10 potential host species breeding in sympatry with four different cuckoo species in an area in Bangladesh using differently coloured model eggs to test host responses. In four species we introduced both mimetic and non‐mimetic eggs. Black Drongos Dicrurus macrocercus, hosts of the Indian Cuckoo Cuculus micropterus, rejected all model eggs. Common Mynas Acridotheres tristis and Jungle Babblers Turdoides striata accepted all eggs regardless of mimicry. These two species are parasitized by Asian Koels Eudynamys scolopaceus, Common Hawk‐cuckoo Hierococcyx varius and, in the case of Jungle Babblers, Jacobin Cuckoos Clamator jacobinus. Pied Mynas Gracupica contra, with no records of parasitism in our study area, also accepted all eggs regardless of mimicry. In the six remaining species, all of which lay spotted eggs, we introduced only non‐mimetic eggs. Black‐hooded Orioles Oriolus xanthornus rejected all model eggs, even though we have found no records of natural parasitism. Long‐tailed Shrikes Lanius schach and House Crows Corvus splendens, hosts of Asian Koels, rejected 75 and 9.1% of model eggs, respectively. Large‐billed Crows Corvus macrorhynchos, apparently not used as hosts in our study area, accepted all blue but rejected all brown model eggs. Oriental Magpie‐Robins Copsychus saularis and Red‐vented Bulbuls Pycnonotus cafer accepted all non‐mimetic model eggs. In Black Drongos, Long‐tailed Shrikes and Black‐hooded Orioles, all model eggs were ejected within 24 h of introduction. The results show considerable variation in egg rejection rates among various species, providing baseline data for further investigation of co‐evolutionary interactions between brood parasites and hosts in this region.  相似文献   
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