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排序方式: 共有751条查询结果,搜索用时 500 毫秒
41.
AG Baranovskii TG Kanyshkova AS Mogelnitskii VA Naumov VN Buneva EI Gusev AN Boiko TA Zargarova OO Favorova GA Nevinsky 《Canadian Metallurgical Quarterly》1998,63(11):1239-1248
It is known that in the blood of patients with some autoimmune diseases catalytically active antibodies hydrolyzing proteins, DNA, and RNA may be detected. In the present work homogeneous preparations of IgG antibodies (Ab) possessing high affinity for nucleic acids (NA) were obtained for the first time from blood and cerebrospinal fluid of patients with multiple sclerosis (MS). The fraction of IgG Ab as well as its Fab fragments and isolated light chains of both kappa- and lambda-types were shown to catalyze effectively the hydrolysis of DNA and RNA. It is shown by different methods that the capability for nucleic acid hydrolysis is an intrinsic property of the polyclonal Ab. NA-hydrolyzing Ab were detected in the blood of 69 of 72 and in the cerebrospinal fluid of 5 of 5 examined MS patients, while they were not detected in the blood of any of 50 healthy donors examined. Comparison of relative rates of RNA hydrolysis and of the substrate specificity in hydrolysis of various model RNAs--cCMP, poly(U), poly(A), and poly(C)--revealed pronounced differences of MS antibodies from ribonucleases of human blood, ribonuclease A, and all earlier described abzymes. The abzymes are usually characterized by relatively low specific activities in comparison with that of normal enzymes catalyzing analogous reactions. Ab from the blood of MS patients are the first example of autoabzymes whose specific activity in RNA hydrolysis is comparable or even higher than that of pancreatic ribonuclease A--one of the most active RNA-hydrolyzing enzymes. 相似文献
42.
EI Severinsson 《Canadian Metallurgical Quarterly》1998,27(6):1269-1277
This paper describes nursing students' views of a supervision programme provided during the second semester of their education, which was their first period of nursing practice. A form with open questions and a 24-item questionnaire were completed by the 28 nursing students. The analysis of their responses was a combination of factor analysis and grounded theory approach, based on comparative analysis. The results indicate two specific effects of the programme: personal growth and integration of knowledge. The process of creating knowledge includes four stages: awareness of concepts and phenomena, development of a 'language of caring', development of a 'model' of communication, and reflection gained as an effect of the intervention. The nursing students reported that reflection was a way to bridge the gap between theory and practice. Their views of the effect of the supervision showed high values for the following three factors: improved interpersonal skills, improved professional skills, and improved communication skills. 相似文献
43.
AV Nedostup EA Bogdanova EI Mikhnovski? AA Platonova 《Canadian Metallurgical Quarterly》1977,17(4):85-90
The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization. 相似文献
44.
The persistence of metatarsus adductus varus has been a problem in management. We have treated a series of selected patients with this problem and believe that our results have been better than with the procedure we have used in the past. Fowler has described a procedure which seems ideal for the patients in our series. Through personal communication the procedure and its application were discussed and the series was started eight years ago. Our series is small because our patients are responding to other forms of treatment at an earlier age. The few that do not respond are now considered for the operation described. The procedure is relatively simple to perform. Full correction should be obtained at the time of surgery. Casting is utilized to hold the correction and immobilize the extremity for healing. Our unsatisfactory results occurred because of errors in technique or poor selection of patients. We believe that this procedure should be considered in the older patient with metatarsus varus. 相似文献
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46.
L. A. Polovikhina O. I. Sergeeva M. P. Zverev L. K. Kuznetsova Yu. A. Svetlitskii 《Fibre Chemistry》1989,21(1):72-75
Conclusions A technological process has been developed for preparing modified film yarns from a mixture of polypropylene and low density polyethylene having a content of the latter up to 10% by wt.; these yarns are used to make goods for national consumption or technical articles, with an economic advantage of 50 rubles per metric ton of yarn.When small additions of LDPE are introduced into polypropylene, an increase in the degree of yarn stretch is observed.The suggestion has been made that small additions of LDPE heal defects in the structure of oriented polypropylene, which is prone to spontaneous fibrillation; this aids in obtaining yarns with increased strength, elasticity, and lower tendency to split.Translated from Khimicheskie Volokna, No. 1, pp. 45–47, January–February, 1989. 相似文献
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49.
Т.А. Sergeyeva L.A. Gorbach О.А. Slinchenko L.A. Goncharova O.V. Piletska О.О. Brovko L.M. Sergeeva G.V. Elska 《Materials science & engineering. C, Materials for biological applications》2010,30(3):431-436
Colorimetric test-system for the express-control of phenols content in water was developed. The system consisted of free-standing molecularly imprinted polymer (MIP) membranes which contained synthetic binding sites capable of phenol binding. The MIP membranes were obtained by co-polymerisation of a functional monomer (e.g. itaconic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid, acrylamide or methacrylic acid) with triethyleneglycoldimethacrylate and oligourethaneacrylate. Rational choice of the functional monomers was based on the results of computational modelling. The phenol-selective MIP membranes were used as a basis for the colorimetric test-system for measuring phenol in aqueous samples. Phenol molecules were selectively adsorbed by the MIP membranes and quantified using color reaction with 4-aminoantipyrine. The intensity of the membranes' staining was proportional to the phenol concentration in the analysed sample. The optimised colorimetric test-system based on MIP membranes demonstrated a low detection limit (50 nM), a wide working range — 50 nM–0.5 mM and an excellent storage stability at room temperature (12 months). As compared to the traditional methods of phenols detection the developed test-system is superior because of simplicity of operation, small size and low cost. 相似文献
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