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1.
Preliminary treatment of erythrocyte suspension with trypan blue solution did not affect their capacity to participate in the reaction of spontaneous rosette formation, but permitted to differentiate them in a mixture with other erythrocytes after staining with methyl-green-pyronine on a fixed slide. By using a mixture of such marked erythrocytes sensitized with antibodies and a complement, the presence in the peripheral blood of healthy people of a small lymphocyte subpopulation connecting these two types of indicator particles was demonstrated.  相似文献   
2.
The first data about the diatoms of phytobenthos and epiphyton in water biotopes of a peatbog in the Kolva River basin (a tributary of the Pechora River) polluted by oil-field brines are reported. As a total, 49 species with varieties and forms from 14 genera and 9 families have been found. Dominating complexes of communities with halophilic diatoms have been revealed. The ecology of the species resistant to mineral pollution is discussed.  相似文献   
3.
The activities of green cell-free extracts of spinach leavesin performing photochemical transphosphorylation, photosyntheticphosphorylation, the HILL reaction and the light-induced formationof the endogenous reducing substance (ascorbic acid) were followedin parallel during the growth process of the plant. There wasa certain parallelism between the development of the activitiesof photochemical transphosphorylation, of photo-synthetic phosphorylationand of the HILL reaction, activities being low in the earlierstage of growth, reaching a maximum just before efflorescence,and showing thereafter a more or less sharp decline. The activityin the light-induced formation of endogenous reducing substancewas undetectable for the first 35 day-period of growth, reacheda maximum about one week earlier than the other three activities,and again disappeared after 60 days of growth. (Received September 9, 1960; )  相似文献   
4.
Examination of children with different noninfectious diseases resulted in obtaining the data base on the state of health of 201 children belonging to the potential risk group of the development of secondary immunodeficiency. The children were subdivided into several groups which differed by the type of immune disturbances and accompanying metabolic shifts. The level of antibodies to one of the fragments of peptidoglycan-N-acetylmuramyldipeptide was compared with the character of changes in the immune system. Different titers of serum antibodies to peptidoglycan were found to correspond to different forms of immune disturbances. The study showed that from the group with the absence of definite signs of immunodeficiency to the group with the pronounced deficiency of T lymphocytes and monocytes expressing CD14 antigen changes in the immune system increased in parallel to a rise in the concentration of alpha 2-macroglobulin, the development of hypercholesterolemia and a decreased level of antibodies to peptidoglycan. Opportunistic microflora was seemingly an important factor in the formation of definite forms of disturbances of the immune system and accompanying metabolic shifts.  相似文献   
5.
The effect of the inclusion of probiotic preparations for the correction of disturbances in normal intestinal microflora into the complex therapy of patients wish Duchenne's childhood muscular dystrophy and Becker's myopathy was analyzed. Probiotic therapy made it possible to improve the clinical state of patients, manifested by an increase in muscular strength and accompanied by positive shifts in electromyographic, immunological, biochemical, hormonal characteristics. Intestinal microbiocenosis plays seemingly a certain role in the formation of hereditary pathology.  相似文献   
6.
A fungal endo-ß-l,3-glucanase was compared with afungal exo-ß-1,3-glucanase with respect to their effectson elongation and cell-wall extensibility in oat coleoptilesegments. The exo-enzyme enhanced elongation and extensibilityof the cell wall. Its effect was not additive to the effectof indole-3-acetic acid when given together with the latter,at least during 3 hr of incubation. Endo-glucanase showed nosignificant effect on elongation and no interaction with theexo-enzyme. Auxin and exo-glucanase increased extensibilityof the cell wall. The exo-glucanase was separated by isoelectricfocusing. The two fractions which were separated and showedglucanase activity induced elongation and cell wall loosening. (Received March 16, 1970; )  相似文献   
7.

Background  

The agriculturally important pasture grass tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh.) is an outbreeding allohexaploid, that may be more accurately described as a species complex consisting of three major (Continental, Mediterranean and rhizomatous) morphotypes. Observation of hybrid infertility in some crossing combinations between morphotypes suggests the possibility of independent origins from different diploid progenitors. This study aims to clarify the evolutionary relationships between each tall fescue morphotype through phylogenetic analysis using two low-copy nuclear genes (encoding plastid acetyl-CoA carboxylase [Acc1] and centroradialis [CEN]), the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS) and the chloroplast DNA (cpDNA) genome-located matK gene. Other taxa within the closely related Lolium-Festuca species complex were also included in the study, to increase understanding of evolutionary processes in a taxonomic group characterised by multiple inter-specific hybridisation events.  相似文献   
8.

Background  

White clover (Trifolium repens L.) is an outbreeding allotetraploid species and an important forage legume in temperate grassland agriculture. Comparison of sub-genome architecture and study of nucleotide sequence diversity within allopolyploids provides insight into evolutionary divergence mechanisms, and is also necessary for the development of whole-genome sequencing strategies. This study aimed to evaluate the degree of divergence between the O and P' sub-genomes of white clover through sequencing of BAC clones containing paired homoeoloci. The microsyntenic relationships between the genomes of white clover and the model legumes Lotus japonicus and Medicago truncatula as well as Arabidopsis thaliana were also characterised.  相似文献   
9.
The vitamin K-dependent (VKD) carboxylase binds VKD proteins via their propeptide and converts Glu's to gamma-carboxylated Glu's, or Gla's, in the Gla domain. Multiple carboxylation is required for activity, which could be achieved if the carboxylase is processive. In the only previous study to test for this capability, an indirect assay was used which suggested processivity; however, the efficiency was poor and raised questions regarding how full carboxylation is accomplished. To unequivocally determine if the carboxylase is processive and if it can account for comprehensive carboxylation in vivo, as well as to elucidate the enzyme mechanism, we developed a direct test for processivity. The in vitro carboxylation of a complex containing carboxylase and full-length factor IX (fIX) was challenged with an excess amount of a distinguishable fIX variant. Remarkably, carboxylation of fIX in the complex was completely unaffected by the challenge protein, and comprehensive carboxylation was achieved, showing conclusively that the carboxylase is processive and highly efficient. These studies also showed that carboxylation of individual fIX/carboxylase complexes was nonsynchronous and implicated a driving force for the reaction which requires the carboxylase to distinguish Glu's from Gla's. We found that the Gla domain is tightly associated with the carboxylase during carboxylation, blocking the access of a small peptide substrate (EEL). The studies describe the first analysis of preformed complexes, and the rate for full-length, native fIX in the complex was equivalent to that of the substrate EEL. Thus, intramolecular movement within the Gla domain to reposition new Glu's for catalysis is as rapid as diffusion-limited positioning of a small substrate, and the Gla domain is not sterically constrained by the rest of the fIX molecule during carboxylation. The rate of carboxylation of fIX in the preformed complex was 24-fold higher than for fIX modified by free carboxylase, which supports carboxylase processivity and which indicates that binding and/or release is the rate-limiting step in protein carboxylation. These data indicate a model of tethered processivity, in which the VKD proteins remain bound to the carboxylase throughout the reaction via their propeptide, while the Gla domain undergoes intramolecular movement to reposition new Glu's for catalysis to ultimately achieve comprehensive carboxylation.  相似文献   
10.
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