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911.
912.
Water as ligand: preferential binding and exclusion of denaturants in protein unfolding. 总被引:8,自引:0,他引:8
S N Timasheff 《Biochemistry》1992,31(41):9857-9864
913.
There are many situations in which grain distributions resulting from in situ hybridization of radioactively labeled probes to unique genes should be subjected to a statistical analysis. However, the problems posed by analysis of in situ hybridization data are not straightforward, and no completely satisfying method is currently available. We have developed a procedure in which the major and any number of minor site(s) of hybridization may be specifically located and the significance of each tested. This zmax procedure first tests the overall distribution for departure from randomness and then identifies significantly overlabeled whole chromosomes (or chromosome arms or other large segments), a process that may be repeated to pinpoint significantly overlabeled regions within these chromosomes. We describe in detail the derivation of the zmax statistic, present tables of significant zmax levels, and show with examples how zmax is used in tests of significance of in situ hybridization data. 相似文献
914.
T M Zheltikova V M Berzhets A D Petrova-Nikitina A Kh Kanchurin 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(6):80-83
The acarological+ study of dust samples from the homes of allergic patients and normal persons in Moscow mite antigens were detected, respectively, in 66.7% and 38.1% of homes. The indirect mast cell degranulation test and the brain gliacyte volume change test in white rats gave similar results. The occurrence of Dermatophagoides pteronyssinus was approximately twice as great of D. farinae, and the numerical prevalence of the former species over the latter one was 1.3-fold. Dermatophagoides mites occurred in the homes of allergic patients 1.8-2.3 times as frequently as in the homes of normal persons. 相似文献
915.
Summary The rhizosphere microflora of arecanut palm under continuous application of organic manures and inorganic fertilizers was
studied. The nutrients applied are 100 g N, 40 g P2O5 and 140 g K2O/palm/year in the form of organics and inorganics. The application of organic manure increased the microbial population.
The increase in microbial population was observed between the rhizosphere samples collected at 0–30cm and 30–60 cm depths.
The surface cultivation of soil increased the microbial population.Trichoderma sp. andAspergillus sp. dominated in therhizosphere of arecanut palm.
Contribution No. 208. Central Plantation Crops Research Institute, Vittal-574243, Karnataka, India. 相似文献
916.
V M Morogova R Sh Magazov A V Dulina D V Krutilina R S Shafeeva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(12):65-67
The production of virus-neutralizing antibodies in high titers has been found to occur in persons immunized with tissue-culture rabies vaccines, concentrated and non concentrated, intramuscularly in a dose of 1 ml in accordance with reduced immunization schedules. 相似文献
917.
Summary Soil tests, plant performance, and plant tissue analyses were used to study the availability of sulfur to wetland rice in
30 Philippine soils.
The critical concentrations of available sulfur by the calcium phosphate, lithium chloride, ammonium acetate, and hydrochloric
acid extractions were 9, 25, 30, and 5 mg/kg, respectively.
The critical total sulfur limits were 0.11% in the shoot at maximum tillering 0.055% in the straw at maturity, and 0.065%
in the grain. The critical N:S ratio was 15 in the shoot at maximum tillering, 14 in the straw at maturity, and 26 in the
grain. The critical sulfate-sulfur limit was 150 mg/kg in the shoot at maximum tillering and 100 mg/kg in the straw at maturity.
The critical sulfate-sulfur/total sulfur percentage ratio was 15% in the shoot at maximum tillering and the straw at maturity.
Plant performance, judged by appearance and yield of dry matter, straw, and grain, was generally poorer in the sulfur deficient
soils than in the other soils. Although the calcium phosphate and ammonium acetate methods gave a better correlation between
plant performance and available sulfur than the others, all four methods separated sulfur-deficient soils from non-deficient
ones. The hydrochloric acid method merits further study because it is simple and versatile. 相似文献
918.
Human globin genes can be transferred into mouse and human erythroid cells in culture, and can be appropriately expressed at the mRNA level in these cells. A plasmid containing a human beta globin gene is expressed in mouse erythroleukemia cells (MELC), and another containing a human epsilon or gamma gene is expressed in human erythroleukemia (K562) cells. A neomycin resistance (neoR) gene on the plasmids has been used to select for those cells containing the transferred globin genes; this selection may favor the expression of the globin genes by providing chromosomal positions requiring neoR expression. Analyzing clones resistant to G418, a neomycin analogue, demonstrated globin mRNA expression and induction. Retroviral vectors have also been used to transfer and appropriately express human beta genes in MELC. In addition, a plasmid containing a dihydrofolate reductase (DHFR) gene as well as neoR and beta globin genes has been used to amplify and express beta globin mRNA in MELC. These experiments suggest that high level appropriate expression of human beta globin genes is feasible and provides potentially useful approaches to the long-range goal of gene therapy for sickle cell anemia and beta thalassemia. 相似文献
919.
Histological and electron-microscopic radioautographic investigations of regenerating medullar tissue were performed in rabbits following curettage. Low differentiated connective tissue cells were shown to possess the highest proliferative activity. DNA synthesis mainly took place in low differentiated, endothelial and osteogenic cells. It is suggested that low differentiated cells take part in histogenesis of regenerating medullar tissue, including osteo- and angiogenesis. 相似文献
920.
Iu I Afanas'ev O i Mikha?lov V I Nozdrin G V Nikitenkova M I Rytikova 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(1):22-24
Human and animal blood smear staining with PAPh has revealed mononuclear leukocyte-erythrocyte aggregates. Administration of retinoic acid increased concentration and dimensions of these aggregates and was followed by preferential accumulation of PAPh-negative osmotically unstable erythrocytes. Similar changes were detected in the blood samples of women engaged in the production of retinoic acid. Aggregate concentration showed positive correlation with erythrocyte sedimentation rate and no correlation with prothrombin time. 相似文献