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排序方式: 共有851条查询结果,搜索用时 26 毫秒
1.
Ipratropium bromide is a synthetic derivative of atropine with little absorption when used in inhalation, and therefore little secondary effects. The authors review its pharmacological properties and therapeutic efficacy in the treatment of asthma in children. Combined nebulized inhalation of ipratropium bromide and beta 2 sympathomimetic results in a more efficient and more sustained bronchodilatation than beta 2 sympathicomimetic alone in the treatment of acute asthma in children. Ipratropium bromide should be usefully introduced in the therapeutic scheme of acute asthma in children. Further studies will be necessary in order to determine its efficacy and tolerance in infants. 相似文献
2.
N G Bogdanov L G Gvozdova M S Belakovski? A N Smirnova N V Blazheevich 《Voprosy pitaniia》1986,(3):28-31
Supply of the main and doubling crews of cosmonauts with vitamins C, A, D, E, B1, B2, B6, PP, and B12, folic acid and carotinoids was studied during training and after the completion of short-term space flights (from 4 to 13 days). As the result of the investigation conducted during the intensive training, 1 month before the space flight some cases of certain vitamins deficiency were revealed. Administration of additional vitamins during 2 weeks before the flight led to a rise in the cosmonauts' supply with vitamins. The findings obtained after the short-term space flights evidence an intensive metabolization of vitamins and increased vitamin requirements during this period. 相似文献
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5.
ZA Varga JF Thompson JC Locke-Edmunds RN Baird JR Farndon 《Canadian Metallurgical Quarterly》1995,82(6):765-769
The Haemocell S-350 device has recently been introduced for intraoperative autotransfusion. The system uses a novel membrane filter to process shed blood. In the first part of this study a 0.2-micron pore size filter was used in a randomized trial comparing the use of autotransfusion (n = 8) with bank blood controls (n = 9) during aortic reconstruction. This part of the trial was abandoned because of unexpected non-surgical bleeding. Bank blood requirements fell from a median of 3.0 (range 0.0-9.0) units to 1.5 (range 0.0-7.0) units when autotransfusion was used, but these patients had a greater perioperative blood loss (1791 (range 932-3104) versus 1140 (range 440-3840) ml). There was evidence of postoperative heparin excess with an activated partial thromboplastin time ratio of 1.3 (range 0.9-3.0) versus 1.0 (range 1.0-1.2) in controls and an activated clotting time of 206 (range 143-280) versus 137 (range 107-142) s. This was confirmed by raised plasma heparin levels and a prolonged thrombin time normalized by protamine. To improve performance a 0.6-micron pore size filter was studied in ten patients. Filtration efficiency doubled from 19 to 38 per cent. Electron micrographs demonstrated better filter clearance, but 44 per cent of the original concentration of heparin remained in the reinfusate. The S-350 device may be an attractive alternative to centrifugation for intraoperative autotransfusion but, until efficiency is improved, it should only be used for cardiovascular surgery when excess heparin can be reversed with protamine. 相似文献
6.
I. V. Zhuravlev D. S. Kibalov G. F. Smirnova V. K. Smirnov 《Technical Physics Letters》2003,29(11):949-950
Wavy nanostructures are formed on the ion-bombarded surface of single-crystal and amorphous silicon films prepared by various
methods. The period and depth of this structure have been determined as functions of the angle of incidence and the energy
of nitrogen ions used for the surface sputtering. A comparative analysis of SEM images of the wavy surface nanostructures
on various silicon films has been performed using a two-dimensional Fourier transform. The films of amorphous silicon obtained
by electron beam deposition and magnetron sputtering techniques are closest to single-crystal silicon films with respect to
the wavy surface nanostructure formation. 相似文献
7.
The main stages in the development of a process for preparing actinides by underground nuclear explosions in rock salt at the Galit field are considered. The data of experiments performed by researchers of the Khlopin Radium Institute in the course of the process development are analyzed. The results of detailed study of the cavities after underground nuclear explosions and properties of the resulting radioactive products reprocessed for recovery of actinides are presented. 相似文献
8.
Schistosoma mansoni and S. japonicum infections in nude mice (nu/nu) were compared with infections in nu/+ heterozygotes or intact mice. Seven to 12 weeks after exposure to S. mansoni, the responses of Swiss NCR, C3H, BALB/c and C57B1/6 nude mice did not differ substantially. Nude mice of all these strains showed minute granulomas around eggs in the liver and minimal hepatic fibrosis. Microvesicular and necrotizing changes in hepatocytes were similar in all mouse strains, and S. mansoni infections were frequently lethal to nude, but not to intact mice between the seventh and ninth weeks of infection. Nude mice that survived the ninth week of infection generally lived until the 12th week. The number of eggs per mature worm pair in the tissues of S. mansoni-infected nude mice was similar to the number in intact mice, but nude mice passed fewer eggs in the feces. Nude mice that received serum from infected intact mice excreted eggs in the stool in numbers equivalent to intact mice, but continued to form minute granulomas around S. mansoni eggs. Reconstitution with fetal thymus or with splenocytes from normal or S. mansoni-infected mice partially or completely restored hepatic granuloma size, granuloma eosinophils, hepatic fibrosis, and excretion of eggs in the feces. In contrast to S. mansoni infection, S. japonicum infections in nude mice did not cause necrosis of hepatocytes or excessive mortality, and S. japonicum eggs were passed in the feces in numbers equivalent to those passed by infected intact mice. 相似文献
9.
M. V. Teploukhova K. E. Perepelkin A. T. Kynin N. A. Smirnova Zh. Yu. Koitova 《Fibre Chemistry》1996,27(4):240-244
The water vapor sorption — desorption isotherms of a series of natural and chemical fibres were determined and the hysteresis coefficients characterizing the nonequilibrium character of the structure and irreversibility of changes in it in sorption of water vapors were calculated. The moisture sorption — desorption isotherms are described by a single equation for a theoretical-probability model. The coefficients of the TPM equation were found for all types of fibres and can be used for predicting the magnitude of sorption and the change in the properties of textile materials in a wide range of external conditions. The points of the beginning of devitrification of the polymer under the effect of moisture were determined.St. Petersburg State University of Design and Technology. Translated from Khimicheskie Volokna, No. 4, pp. 20–23, July–August, 1995. 相似文献
10.
IA Bukaeva NT Ra?khlin NA Probatova EA Smirnova NN Tupitsyn EN Sholokhova R Gossrau 《Canadian Metallurgical Quarterly》1997,59(4):31-38
26 cases of lymphoproliferative diseases were studied: 8 cases of reactive follicular hyperplasia (RFH), 11 cases of non-Hodgkin's malignant lymphomas (NML), 7 cases of lymphogranulomatosis (LGM). Only gamma-glutamyl transpeptidase (GGT) was found in lymphoid cells of B- and T-dependent areas of lymph nodes with reactive changes as well as in tumor cells of NML and LGM. GGT activity was more pronounced in NML of high-grade malignancy (centroblast and immunoblast) as compared to lymphomas of lower grade of malignancy (lymphocytic, centroblast-centrocytic and in Lennert lymphoma). GGT activity in cells of Hodgkin and Berezovsky-Sterberg in some cases of LGM was high, in others low. Significant differences in GGT activity between RFH and follicular centroblast-centrocytic lymphoma were not found. Activity of aminopeptidase M was observed in histiocytes, fibroblasts, vessels and areas of connective tissue growth. Aminopeptidase A activity was observed in vessels only. Activity of dipeptidyl(amino)peptidase IV was observed in some lymphoid cells in RFH, NML and LGM. Thus, GGT activity may be considered as a differential-diagnostic marker in separating NML of high and low degree of malignancy and this may presume a different sensitivity to the therapy. 相似文献