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991.
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
992.
V N Nikandrov N S Pyzhova V I Votiakov 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(7):49-51
The addition of ATP or 3,5-AMP (but not UTP, GTP, CTP, AMP, 2,3-AMP, ADP, inorganic pyrophosphate) at a final concentration of 10(-1) M into streptokinase solution, pH 7.0 or 9.5, causes a dramatic inhibition of streptokinase-induced fibrinolysis. The specificity of ATP effect is fully lost at pH 3.0, when all nucleotides completely inhibit the activating function of streptokinase. Ribose-5-phosphate causes a similar effect at pH 3.0. The character of nucleotide action on the activating function of streptokinase considerably differs from their influence on proteolytic reactions. 相似文献
993.
G N Kryzhanovski? S I Igon'kina V V Trubetskaia 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(8):149-151
It has been shown that the reaction of both limbs to thermal pain stimulation was suppressed during spinal pain syndrome development caused by generators of pathologically enhanced excitation (GPEE) formed in the dorsal horns of the spinal cord lumbosacral segments on one side. The analgetic effect on physiological pain was retained long after pain syndrome disappearance (48 hours), the effect was bilateral and was independent of the type of agent producing GPEE. It was shown that neuronal activity in the antinociceptive system key structure (nucleus raphe dorsal) increases. It is assumed that physiological pain relief is caused by enhanced activity in antinociceptive system structures in pain syndrome. 相似文献
994.
A M Vikhert V N Rozinova A S Nekrasov S M Sogoian A K Tikhaze 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(11):633-636
Lipid accumulation in the rabbit liver and myocardium has been investigated by histochemical and biochemical methods. The rabbits received cholesterol that contained 5% of autooxidation products or purified cholesterol. Lipid accumulation took place in the liver and intramural myocardial vessels during feeding of rabbits with autooxidated cholesterol. Feeding with pure cholesterol free from autooxidation products caused but slight changes or no changes at all. 相似文献
995.
V G Kubas' O P Danilova N A Nikiforova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1987,(4):58-59
The quantitative study of the reduction capacity of neutrophils with respect to nitro blue tetrazolium in experimental systemic candidiasis has revealed an increase in this capacity within 20 days of the infection. The reduction capacity has been found to depend not only on the degree of the contamination of the body with Candida cells, but also on the stage of the inflammatory process. 相似文献
996.
Dr. N. J. D. Nagelkerke A. A. M. Hart J. Oosting 《Biometrical journal. Biometrische Zeitschrift》1987,29(2):141-145
The consequences of the misspecification of a regression model are considered. For small effects of covariates a proportional consistency theorem is derived. The consistent estimation of the covariance matrix of the estimates is discussed. 相似文献
997.
The study of the adhesion test in suspensions, carried out with 9 C. albicans strains and human buccal epithelial cells, has revealed that these cells are exponentially distributed by the number of C. albicans cells adhered to them. To characterize adhesion, the use of the index of the exponent describing the distribution of epithelial cells is proposed. With the use of this index, 5 C. albicans strains isolated from candidiasis patients have been found to possess, on the average, higher adhesiveness with respect to epithelial cells than 4 strains isolated from persons without symptoms of candidiasis. 相似文献
998.
999.
1000.
M McEvoy K Porter P Mortimer N Simmons D Shanson 《BMJ (Clinical research ed.)》1987,294(6587):1595-1597
In a prospective study of 150 health care workers in the United Kingdom who had been accidentally exposed to the human immunodeficiency virus no evidence of transmission was found. Larger studies in the United States and anecdotal accounts in publications from other countries confirm that the risk of occupational infection is very low. Health care workers must adopt safe procedures at all times, however, to avoid exposure to infection. 相似文献