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Mycological analysis throughout the vegetation period of potato (Solanum tuberosum) made it possible to study in detail the structure of the micromycete community, to determine typical dominant (frequency, more than 60%), typical common (frequency, 30 to 60%), typical rare (frequency, 10 to 30%), and casual (frequency, less than 10%) species and to estimate changes in the microorganism community caused by plant protection preparations with different mechanisms of action. It was shown that, as a result of occurrence of resistant forms, synthetic preparations against fungal pathogens of potato (such as TMTD, Ridomil gold MC, and Cupricol) were only slightly more effective than biological preparations (Trichodermin and AgroChit), with the former considerably changing the natural saprophytic mycological community. An increase in the soil pool of Trichoderma harzianum as a result of application of a biological preparation based on this antagonistic fungus correlated with its effectiveness against the soil pathogen Fusarium sp., which causes root rot. A chitosan-based elicitor preparation more effectively suppressed the development of early (Alternaria sp. and Macrosporium sp.) and late (Phytophthora sp.) blighting of leaves and had a weaker effect on soil microflora.  相似文献   
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The authors suggest a method for quantitative diagnosis of the functional state of the afferent pathways of the spinal cord by magnetic stimulation in the projection of the vertebrae CVI–CVII and LIII–LIV. The induced motor response (IMR) was recorded from the orbicular muscle of the eye. The velocity of propagation of excitation (VPE) along the afferent pathways between the vertebrae CVI–CVII and LIII–LIV was measured as the ratio of the distance between two stimulation points (along the coil center) to the difference between the latent periods of the recorded IMRs. In healthy adults, VPE was 77.93 ± 4.93 m/s, and in healthy children, 7- to 14-years old, it was 77.60 ± 4.12 m/s. In patients with disseminated sclerosis, this index was 40.15 ± 14.81 m/s. The asymmetry value (AV) was 5.31 ± 1.20 m/s. The VPE and AV in patients with disseminated sclerosis differed significantly from those in healthy subjects of same sex and age (p < 0.05).  相似文献   
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The phospholipid composition of 6 Brucella species (B. melitensis, B. abortus, B. suis, B. ovis. B. canis, B. neotomae) and Australian mouse-derived strains of Brucella N 4, 11, 12 were studied. Comparison of phospholipid composition of Brucella cells with that of serologically related microorganisms revealed that all Brucella biotypes contain phosphatidyl-(N-methyl)ethanolamine and phosphatidylcholine while Y. enterocolitica, Sh. disenteriae, E. coli cells do not contain these two substances. It is concluded that the specific phospholipid pattern of Brucella biotypes may be useful in typing of new Brucella strains.  相似文献   
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To gain a deeper insight into the relationship between the electrogenesis and oxygenation of the brain, fMRI and EEG reactions to identical functional loads (opening of the eyes and right- and left-hand fingering) were compared in 11 young right-handed healthy subjects with statistical techniques. Changes in power, frequency and coherent EEG parameters obtained by 18-channel monopolar recording were compared with values of + BOLD-fMRI response, calculated for 18 corresponding cortical areas on the basis of application of the "virtual cap" by the original algorithm. In reactive changes of both hemodynamic and bioelectrical parameters, sets of independent factors were identified, which were regarded on the basis of their topography as specific (localized in the cortical representation ofa relevant analyzer) and nonspecific (diffuse and similar under different functional loads). Specific component dominated in the fMRI response, whereas non-specific component was characteristic of the EEG reaction. The similar topography of reactive fMRI and EEG factors under normal conditions, confirmed by the correlation analysis, reflects the multilevel character of the systemic organization of the brain activity, visualized, in particular, in the sagittal projections of the individual fMRI images. Each of the reactive EEG factors included all of the EEG quantitative characteristics. EEG coherence, which dominated among other parameters (with a local increase in the cortical representation of a relevant analyzer and a diffuse decrease in the areas of the influence of the regulatory structures) displayed the highest correlation with hemodynamic responses of the brain.  相似文献   
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In the process of dynamic study of cortical bioelectrical activity and indices of its intercentral interaction in 52 neurosurgical patients with focal lesion on the brainstem level, the dependence was shown of the CNS reactions to the operative intervention on the character and degree of damage. Variants were described of compensatory neurodynamic reconstructions of electrical processes in observations with transient, stable and irreversible pathological foci of brainstem localization.  相似文献   
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