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21.
GN Kremenchutski? ML Gorbunova LG Iurgel' VI Chu?ko SA Cherniaev 《Canadian Metallurgical Quarterly》1994,56(4):36-42
The paper deals with the data on biology of Aerococcus, a slightly studied group of microorganisms. Physiological-biochemical properties of Aerococcus are described, data of their distribution in nature are given. Peculiar attention is paid to the estimate of the role of Aerococcus in human microbiocenoses. As a result of the profound and all-round study of this group of microorganisms the authors have developed new bacterial drug "A-bakterin" based on the aerococcus strain. Data presented about the results of clinical tests of "A-bakterin" are presented, a possibility to use Aerococcus lysate in the elaboration of new drugs is discussed. 相似文献
22.
IuM Evdokimov SG Skuridin SV Semenov VI Salianov GB Lortkipanidze 《Canadian Metallurgical Quarterly》1998,43(2):240-252
Abnormal optical properties of liquid-crystalline dispersions (phases) formed as a result of phase exclusion of double-stranded DNA and RNA from water-salt poly(ethylene glycol) solutions and X-ray parameters of these phases are compared. It is shown that the cholesteric packing of nucleic acid molecules is realized at the certain osmotic pressure of a solvent only. A comparison of the optical properties of liquid-crystalline phases (dispersions) to their X-ray parameters allows one to put forward a suggestion on various hydratation (fluctuation) regimes of the nucleic acid behaviour under the condensed phases formation and factors, influencing the mode of packing of these molecules in phases formed. It is shown as well, that immobilization of DNA cholesteric liquid-crystalline particles in the content of polymeric matrix is accompanied by the stabilization of these particles and, hence, their specific abnormal optical activity as well as by formation of particles having a structure, which corresponds to the "optically isotropic ordered liquid" without abnormal optical activity. Data on stabilization of the cholesteric structure of liquid-crystalline DNA dispersions by creation of polymeric chelate bridges between the neighbouring DNA molecules, fixed in the structure of liquid-crystalline dispersions, are shown. 相似文献
23.
Sequences of fast-folding model proteins (48 residues long on a cubic lattice) were generated by an evolution-like selection toward fast folding. We find that fast-folding proteins exhibit a specific folding mechanism in which all transition state conformations share a smaller subset of common contacts (folding nucleus). Acceleration of folding was accompanied by dramatic strengthening of interactions in the folding nucleus whereas average energy of nonnucleus interactions remained largely unchanged. Furthermore, the residues involved in the nucleus are the most conserved ones within families of evolved sequences. Our results imply that for each protein structure there is a small number of conserved positions that are key determinants of fast folding into that structure. This conjecture was tested on two protein superfamilies: the first having the classical monophosphate binding fold (CMBF; 98 families) and the second having type-III repeat fold (47 families). For each superfamily, we discovered a few positions that exhibit very strong and statistically significant "conservatism of conservatism"-amino acids in those positions are conserved within every family whereas the actual types of amino acids varied from family to family. Those amino acids are in spatial contact with each other. The experimental data of Serrano and coworkers [Lopez-Hernandez, E. & Serrano, L. (1996) Fold. Des. (London) 1, 43-55]. for one of the proteins of the CMBF superfamily (CheY) show that residues identified this way indeed belong to the folding nucleus. Further analysis revealed deep connections between nucleation in CMBF proteins and their function. 相似文献
24.
VI Zadorozhnaia 《Canadian Metallurgical Quarterly》1996,58(3):83-87
Materials are presented concerning the study of a possibility to use highly active carbon sorbent "Dnepr-MH" to liberate the tape water from enteroviruses. Investigations were carried out on the model of the vaccine strain of type-II poliovirus. The sorbent samples, most active in respect of the virus sorption and differing by benzene capacity, were determined. Optimal concentration of a sorbent has been established, pH and water temperature were chosen under which the sorption processes are more active. High efficiency of tape water deprive of enterovirus pollution with the help of the above sorbent is demonstrated in the experiment. 相似文献
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M Feuerstein LM Burrell VI Miller A Lincoln GD Huang R Berger 《Canadian Metallurgical Quarterly》1999,35(3):232-245
Carpal tunnel syndrome (CTS) is a disorder frequently encountered by occupational health care specialists. The health care management of this disorder has involved a diverse set of clinical procedures. The present article is a review of the literature related to CTS with an emphasis on occupational-related CTS. MEDLINE, Cumulative Index to Nursing and Allied Health Literature, PsycLIT, and NIOSHTIC databases from 1985-1997 were searched for treatment outcome studies related to CTS. Treatments of interest included surgery, physical therapy, drug therapy, chiropractic treatment, biobehavioral interventions, and occupational rehabilitation. A systematic review of the effects of these interventions on symptoms, medical status, function, return to work, psychological well-being, and patient satisfaction was completed. Compared to other treatments, the majority of studies assessed the effects of surgical interventions. Endoscopic release was associated with higher levels of physical functioning and fewer days to return to work when compared to open release. Limited evidence indicated: 1) steroid injections and oral use of B6 were associated with pain reduction; 2) in comparison to splinting, range of motion exercises appeared to be associated with less pain and fewer days to return to work; 3) cognitive behavior therapy yielded reductions in pain, anxiety, and depression; and, 4) multidisciplinary occupational rehabilitation was associated with a higher percentage of chronic cases returning to work than usual care. Workers' compensation status was associated with increased time to return to work following surgery. Conclusions are preliminary due to the small number of well-controlled studies, variability in duration of symptoms and disability, and the broad range of reported outcome measures. While there are several opinions regarding effective treatment, there is very little scientific support for the range of options currently used in practice. Despite the emerging evidence of the multivariate nature of CTS, the majority of outcome studies have focused on single interventions directed at individual etiological factors or symptoms and functional limitations secondary to CTS. 相似文献
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Empirical analysis of the profitability of moderate grazing are presented based on sample dairy farms in Pennsylvania and New York. Net income per cow was higher for dairy farms that employed moderate intensive grazing than for dairy farms that employed extensive grazing. Income appeared to be adequate for family living expenses, but moderate intensive grazing could not be considered a high profit system. Detailed analyses of dairy farms that employed moderate and extensive grazing in northern Pennsylvania indicated that returns to management and owner equity were higher for pasture enterprises than for corn silage or hay enterprises. Positive dairy profits were related to lower feed costs. Milk production was lower on farms that employed moderate grazing than on farms that employed extensive grazing. Logit regression analysis characterized farms that employed moderate intensive grazing as oriented toward dairy rather than toward crop production; these farms had lower culling rates and a greater dependence on milk sales as a share of total sales. The reduced use of fertilizers and chemicals suggests that moderate grazing had environmentally sustainable features. 相似文献