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261.
The association is considered between P. K. Anokhin's ideas and the concept of universal evolutionalism. The interrelation is also analyzed of P. K. Anokhin's concept with the theory of self-organizing systems. The present views on the self-organization principle are analyzed. The prerequisites of development are considered and the content is presented of the main principles of synergetics. A thesis is advanced about the incorrect application of the knowledge concerning self-organization of physicochemical systems to biological and social systems. A conclusion is substantiated that P. K. Anokhin's theory of functional systems is of important significance for development of a new trend in synergetics, i.e., neurosynergetics. 相似文献
262.
M Martínez Ferro R Milner L Voto J Zapaterio C Cannizzaro S Rodríguez G Bonifacino JM Sanchez NS Adzick 《Canadian Metallurgical Quarterly》1998,13(6):343-347
Studying the electrophysiological characteristics of the various types of Charcot-Marie-Tooth disease is important in the understanding of its pathophysiology. The purpose of this study was to identify the frequency of fibrillation potentials and positive sharp waves (FP/PWs) in HMSN I and II and, since they are indices of denervation, to elucidate whether they are correlated with the amplitude of compound muscle action potentials (CMAP). We reviewed the electrophysiological findings of 47 patients who have been studied in our hospital and found to suffer from Charcot-Marie-Tooth polyneuropathy. FP/PW were graded according to a 4-grade scale and the 38 m/sec criterion for motor conduction velocity (MCV) was used for distinction between HMSN I and II subgroups. Seventy percent of HMSN II patients and 81% of HMSN I patients showed fibrillation potentials in the upper or lower limbs. There was no difference in the frequency of FP/PW appearance between the two groups. In the HMSN II group the FP/PW grade correlated with CMAP amplitude in the upper limbs. In both groups there was no correlation between FP/PW grade and MCV. Our findings might indicate that in HMSN I there is a considerable axonal destruction that occurs concurrently with myelin loss. 相似文献
263.
T Cheng NS Peachey S Li Y Goto Y Cao MI Naash 《Canadian Metallurgical Quarterly》1997,17(21):8118-8128
Haploinsufficiency because of a null mutation in the gene encoding peripherin/rds has been thought to be the primary defect associated with the photoreceptor degeneration seen in the retinal degeneration slow (rds) mouse. We have compared the effects of this haploinsufficiency on rod and cone photoreceptors by measuring the levels of rod- and cone-specific gene expression, by determining the relative rates of rod and cone degeneration, and by electroretinography. These analyses were performed at ages before and after the onset of degeneration of the photoreceptor cells. The data were consistent in demonstrating that measures for cone photoreceptors are relatively spared in comparison to comparable measures for rod photoreceptors. Blue cones were retained in higher number than red/green cones for the first 3 months of the degeneration. Our results indicate that the haploinsufficiency present in rds/+ mice has a greater impact on the rod than on the cone photoreceptor, a finding that likely reflects the tight regulation of peripherin/rds and the need for two functional alleles to assemble the structure of the rod outer segment and/or differences between the ultrastructure of the rod and cone outer segments. 相似文献
264.
SG Deeks P Barditch-Crovo PS Lietman F Hwang KC Cundy JF Rooney NS Hellmann S Safrin JO Kahn 《Canadian Metallurgical Quarterly》1998,42(9):2380-2384
9-[2-(R)-(Phosphonomethoxy)propyl]adenine (PMPA) is a nucleotide analogue with potent antiretroviral activity in vitro and in simian models. A randomized, double-blind, placebo-controlled, dose-escalation clinical trial of intravenous PMPA monotherapy was conducted in 20 human immunodeficiency virus (HIV)-infected adults with CD4 cell counts of >/=200 cells/mm3 and plasma HIV RNA levels of >/=10,000 copies/ml. Two dose levels were evaluated (1 and 3 mg/kg of body weight/day). Ten subjects were enrolled at each dose level (eight randomized to receive PMPA and two randomized to receive placebo). On day 1, a single dose of PMPA or placebo was administered by intravenous infusion. Beginning on study day 8, PMPA or placebo was administered once daily for an additional 7 consecutive days. All subjects tolerated dosing without significant adverse events. Mean peak serum PMPA concentrations were 2.7 +/- 0.9 and 9.1 +/- 2.1 microgram/ml in the 1- and 3-mg/kg cohorts, respectively. Serum concentrations declined in a biexponential fashion, with a terminal half-life of 4 to 8 h. At 3 mg/kg/day, a single infusion of PMPA resulted in a 0.4 log10 median decline in plasma HIV RNA by study day 8. Following 7 consecutive days of study drug administration thereafter, the median changes in plasma HIV RNA from baseline were -1.1, -0.6, and 0.1 log10 in the 3-mg/kg/day, 1-mg/kg/day, and placebo dose groups, respectively. Following the final dose in the 3-mg/kg/day cohort, the reduction in HIV RNA was sustained for 7 days before returning toward baseline. Further studies evaluating an oral prodrug of PMPA are under way. 相似文献
265.
A community-based study of Blastocystis and other intestinal parasites in the Asaro Valley, Papua New Guinea showed an extraordinary high prevalence and variety of protozoan infections. Apart from infants, nearly everybody had at least one infection, and the mean number of infections per person was around 2.7. The graph of age-specific prevalence for Blastocystis is similar in shape to those for Entamoeba coli and Endolimax nana, indicating probable similarity in transmission patterns and host response. There was no evidence for pathogenicity of Blastocystis at the community level. Three methods are compared for the measurement of association between infections. Two show strong associations, but these are considered to be the result of parallel age-prevalence curves and environmental factors at the village level. When age- and village-matched pairs were considered, only a weak positive association with E. nana was detectable. 相似文献
266.
267.
AK Dixon AK Gubitz ML Ashford PJ Richardson TC Freeman 《Canadian Metallurgical Quarterly》1995,374(1):135-140
Chinese hamster P-glycoprotein ("multidrug-resistance protein") was purified and reconstituted in proteoliposomes by the procedure of I. L. Urbatsch, M. K. al-Shawi, and A. E. Senior (1994, Biochemistry 33, 7069-7076). The presence of lipid during the octylglucoside solubilization and Reactive Red 120 chromatography steps was found to be mandatory for retention of ATPase activity. Sheep brain or bovine liver lipid extracts could be substituted for the Escherichia coli lipids used previously. Stimulation of ATPase activity of purified, reconstituted P-glycoprotein by vinblastine, colchicine, and daunomycin was seen with sheep brain and bovine liver lipids, but not with E. coli lipids. Basal (i.e., not drug-stimulated) ATPase activity was different in the three lipids. Azidopine labeling of the drug binding sites in purified, reconstituted P-glycoprotein was carried out; vinblastine, colchicine, and daunomycin competed for labeling in all three lipids. It is therefore evident that the lipid environment can significantly influence the characteristics of purified, reconstituted P-glycoprotein ATPase activity and the apparent coupling between drug-binding and catalytic sites. 相似文献
268.
The participation of bacterial parasites belonging to the genus Bdellovibrio in the processes of sewage self-purification was studied in refineries of Pushchino. The lytic activity of Bdellovibrio resulting in a decrease of the number of heterotrophic Gram-negative bacteria and E. coli in sewage was found to depend on the temperature factor influencing the intensity of interaction between the parasite and the host bacterium. The maximal p/h (parasite/host) index was found at the water temperature of 26 degrees C and the minimal one at 19 degrees C. Sewage purified at 26 degrees C and transferred to a precipitation tank contained 800 cells of E. coli in 1 ml while that purified at 19 degrees C contained 4000 cells in 1 ml. The number of interacting organisms varied in sewage which was typical of the "parasite-host" relations. Therefore, Bdellovibrio should be involved in the self-purification of sewage from the intestinal microflora at 26 degrees C; to a lesser extent, at 23.5 degrees C; and not at all, at 19 degrees C. 相似文献
269.
270.
Two fluorochromes, ER-TrackerTM Blue-White DPX dye and the fluorescent brefeldin A (BFA) derivative, BODIPY-BFA, label the endoplasmic reticulum (ER) in hyphal tips of Pisolithus tinctorius and allow its differentiation from the tubular-vacuole system at the light microscope level in living cells. The ER-Tracker dye labels a reticulate network similar in distribution to ER as seen in electron micrographs of freeze-substituted hyphae. BODIPY-BFA stains a thicker axially aligned structure with an expanded region at the apex, which is similar to that seen when hyphae are stained with ER-Tracker dye in the presence of unconjugated BFA. This structure is considered to be ER modified by BFA, a view supported by ultrastructural observations of the effect of BFA on the fungal ER. Both fluorescent probes also stain punctate structures, which are most likely to be Golgi bodies. Neither probe labels the tubular-vacuole system. 相似文献