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21.
D Keeley 《BMJ (Clinical research ed.)》1993,307(6914):1261-1263
The symptoms of many asthmatic patients are poorly controlled, and there are several reasons why this may be so. Doctors fail to find out about symptoms that asthmatic patients are experiencing. Doctors wrongly assume that regular use of bronchodilators in small doses is satisfactory treatment for asthma and that taking high doses of bronchodilator in an asthma attack may be dangerous. Doctors think that inhaled steroids may be dangerous and are reluctant to use them in effective doses. Doctors do not check that patients can use their inhalers properly and do not make enough use of large volume spacers, the best available method for giving inhaled asthma treatment. Doctors undermine patients'' confidence in advice on treatment by failing to ensure that consistent advice is given and often make the management of asthma more troublesome for the patient than the symptoms of asthma. 相似文献
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B. Oderfeld-Nowak W. Jegliski M. Skup J. Skangiel-Kramska M. Zaremba D. Koczyk 《Journal of neurochemistry》1993,61(1):116-119
Abstract: The glial fibrillary acidic protein (GFAP) content was investigated using immunoblotting techniques in the septum and hippocampus of the rat after bilateral lateral fimbria transection. Seven days after surgery GFAP content increased significantly both in the septum (140% of control) and hippocampus (120% in dorsal, the less denervated, and 145% in the most denervated ventral part), indicating the occurrence of reactive gliosis. The GM1 treatment caused statistically significant attenuation of GFAP increment in all hippocampal parts. In contrast, GM1 treatment has no influence on the increase of GFAP content in the septum. Results suggest a differential effect of GM1 on the two gliotic reactions formed as a consequence of the lesion at the level of the source of innervation (septum) and the target (hippocampus). 相似文献
24.
Location of thePoteriocrinus impressus Phillips 1836 holotype has not been known, but it was discovered in the collections of the Natural History Museum, London. Rather than belonging toBlothrocrinus, as suggested by more recent authors, this species should be reassigned toPoteriocrinites. Poteriocrinites impressus is redescribed and photographically illustrated for the first time. 相似文献
25.
Functional and genetic plasticities of the poliovirus genome: quasi-infectious RNAs modified in the 5'-untranslated region yield a variety of pseudorevertants. 总被引:9,自引:4,他引:5 下载免费PDF全文
Poliovirus RNA species with nucleotides 564 to 571 deleted or with a secondary structure domain (positions 564 to 629) replaced by a shorter irregular oligonucleotide have been engineered previously; these RNAs have been considered quasi-infectious (yielding a single late revertant plaque) and dead, respectively (E. Pilipenko, A. Gmyl, Y. Svitkin, S. Maslova, A. Sinyakov, and V. Agol, Cell 68:119-131, 1992). By using large amounts of these RNAs for transfections, revertant clones with a great variety of genetic changes (point mutations, insertions of foreign sequences, short or extended deletions) were isolated. The pattern of these changes supported the notion that an appropriately spaced oligopyrimidine-AUG tandem is important for efficient poliovirus RNA translation. Structural features within and around this tandem modulated the initiation efficiency. The functional and genetic plasticities of the poliovirus genome are briefly discussed. 相似文献
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Joseph T.M. Koumans Hendrica A. Akster Ronald G.H. Booms Jan W.M. Osse 《Differentiation; research in biological diversity》1993,53(1):1-6
Abstract. The in vitro proliferation [uptake of 5-bromo-2'-deoxyuridine (BrdU)] and the degree of differentiation (presence of desmin) of myosatellite cells isolated from white axial muscle of carp between 3 cm and 27 cm standard length (SL) were examined 17 h after isolation. The fraction of the myosatellite cells that were both desmin positive and BrdU positive never exceeded 2% of the total number of isolated myosatellite cells, irrespective of the standard length of the donor(s). This indicates that, for carp, the temporal relationship between replication and desmin expression of myosatellite cells is different from that described for myogenic cells of mammals and birds. The percentage of BrdU positive myosatellite cells was significantly correlated with standard length: it increased from 10% for carp of about 5 cm SL to 40–50% for carp between 20 cm and 27 cm SL. The percentage of desmin positive myosatellite cells was about 50–60%; it was not significantly correlated with standard length. The percentage of myosatellite cells that were both BrdU negative and desmin negative showed a stepwise difference in this percentage with increasing length. Fish smaller than 10 cm SL, had more of these cells (10–40%), than larger fish (which had 0–12%). So, apparently the composition of the myosatellite cell population changes during growth. The low percentage of proliferating cells, and the relatively high percentage of differentiated (desmin positive) myosatellite cells obtained from 3–6 cm large carp, suggests that, in these small fish, muscle growth strongly depends on the use of a pool of myogenic cells that has been formed at an earlier stage of their development. 相似文献
28.
G. M. Obaturov V. V. Moiseenko A. S. Filimonov 《Radiation and environmental biophysics》1993,32(4):285-294
A systemic model describing the major radiobiological effects of various types of radiation is proposed. The model base lines were substantiated, and general mathematical equations for cell survival developed. The model takes into consideration such physical and biological factors as linear energy transfer, ion track structure, and structural and functional organization of interphase chromatin. This paper presents the basic assumptions made and general equations for the cell killing. 相似文献
29.
Sink strength: Learning to measure, measuring to learn 总被引:1,自引:0,他引:1
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