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R Zachariah AD Harries MP Spielmann V Arendt D Nchingula R Mwenda O Courtielle P Kirpach B Mwale FML Salaniponi 《Malawi medical journal : the journal of Medical Association of Malawi》2002,14(2):10-12
In Thyolo district, Malawi, an operational research study is being conducted on the efficacy and feasibility of co-trimoxazole prophylaxis in preventing deaths in HIV-positive patients with tuberculosis (TB). A series of cross-sectional studies were carried out to determine i) whether faecal Escherichia coli (E.coli) resistance to co-trimoxazole in TB patients changed with time and ii) whether the resistance pattern was different in HIV positive TB patients who were taking co-trimoxazole prophylaxis. Co-trimoxazole resistance among E.coli isolates in TB patients at the time of registration was 60% in 1999 and 77% in 2001 (p<0.01). Resistance was 89% among HIV-infected TB patients (receiving co-trimoxazole), while in HIV negative patients (receiving anti-TB therapy alone) it was 62% (p<0.001). The study shows a significant increase of E.coli resistance to co-trimoxazole in TB patients which is particularly prominent in HIV infected patients on co-trimoxazole prophylaxis. Since a high degree of plasmid-mediated transfer of resistance exists between E.coli and the Salmonella species, these findings could herald limitations on the short and long term benefits to be anticipated from the use of co-trimoxazole prophylaxis in preventing non-typhoidal salmonella bacteraemia and enteritis in HIV infected TB patients in Malawi. 相似文献
23.
Aim: to estimate the efficacy of anterior chamber angle reconstruction with lens extraction and IOL implantation in chronic angle-closure glaucoma The results of treatment in 60 eyes of 52 patients (12 males and 40 females) are analyzed. Mean age of the patients was 63.7±3.7 years. Mean IOP before operation was 38 mm Hg (Mentor pneumatonograph Model 30), mean visual acuity 0.32. All the patients used hypotensive eyedrops, 18 相似文献
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V V Ivanov O A Vorob'ev Iu Iu Snipkov 《Kosmicheskaia biologiia i aviakosmicheskaia meditsina》1988,22(4):31-35
The problem of spatial orientation of pilots flying high-altitude aircraft is in the focus of present-day aviation medicine because of a growing number of accidents in the air. One of the productive lines of research is to study spatial orientation in terms of active formation and maintenance of its imagery in a complex environment. However investigators usually emphasize the role of visual (instrumental) information in the image construction, almost ignoring the sensorimotor component of spatial orientation. The theoretical analysis of the process of spatial orientation has facilitated the development of the concept assuming that the pattern of space perception changes with growing professional experience. The concept is based on an active approach to the essence, emergence, formation and variation in the pattern of sensory perception of space in man's consciousness. This concept asserts that as pilot's professional expertise increases, the pattern of spatial orientation becomes geocentric because a new system of spatial perception evolves which is a result of the development of a new (instrumental) type of motor activity in space. This finds expression in the fact that perception of spatial position inflight occurs when man has to resolve a new motor task--movement along a complex trajectory in the three-dimensional space onboard a flying vehicle. The meaningful structure of this problem which is to be implemented through controlling movements of the pilot acts as a factor that forms this new system of perception. All this underlies the arrangement of meaningful collection of instrumental data and detection of noninstrumental signals in the comprehensive perception of changes in the spatial position of a flying vehicle. 相似文献
26.
Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
27.
I S Ivanov 《Voenno-medit?sinski? zhurnal》1992,(6):45-48
For the first time it was Afghanistan where the 40th Army had faced with mass polyinfection morbidity which had a severe course and unfavourable outcome. In these conditions a new effective system of medical care to infectious patients was elaborated and applied. This system comprised a four-staged complex of medical and diagnostical measures. That made it possible to reduce the number of fatal cases by 16 times (from 0.49 to 0.03%) in 1983-1989. The total number of servicemen returned to active duty was brought up to 99.6%. The most important factors in this new system were the following: at prehospital stage--new methods in early definition of infectious patients, opportune diagnosis and emergency care; at hospital phase--new methods of triage, schemes of complex treatment for various nosological forms working principles of intensive therapy. 相似文献
28.
V V Iasnetsov V A Pravdivtsev A V Shashkov L D Smirnov V V Iasnetsov S B Kozlov Iu V Ivanov 《Aviakosmicheskaia i ekologicheskaia meditsina》2005,39(4):45-50
Experiments with rats showed that three out of 12 3-hydroxypyridine derivatives (ethyl-methyl hyd- roxypyrine succinate, SK-132 and IBCP-2 - had an anti-motion sickness effect stronger than of scopolamine, the reference vestiboloprotector. The anti-motion sickness effect of ethyl-methyl hydroxypyrine was also demonstrated in experiments with cats. Apparent anti-motion sickness effect of ethyl-methyl hydroxypyrine (mexydol) was found in 69% of healthy male volunteers which is comparable with the effect of scopolamine (62%). In experiments with immobilized cats (myorelaxation drugs) the microelectrode technique and microontoiphoresis of physiologically active substances revealed that ethylmethyl hydroxypyrine influences the majority of neurons in the medial vestibular nucleus (61%). Suppression of cell spontaneous activities in more than one half of cases can be stopped completely or attenuated significantly by bicucculine, a specific GABA(A)-receptor antagonist. In 42% of neurons ethyl-methyl hydroxypyrine subdues the response to vestibular stimulation which is likely to underlie the anti-motion sickness effect. 相似文献
29.
N Ivanova T Ivanov D Mondeshka N Berova I Angelova R Rakovska S Bojadjiev C Tancheva D Tascheva 《Archiv der Pharmazie》1990,323(1):3-7
The racemic and optically active 4'- and 8-substituted tetrahydroisoquinolines 2-5 have been synthesized and their effect on the water-immersion stress ulcer in rats has been studied. All compounds prevent the formation of stress ulcer, the strongest effect being exhibited by compound 4 and its dextrarotatory isomer (R1 = Cl, R2 = NHCOOC2H5). The antiulcer activity of 4 is 30 to 50 times higher than that of the H2 receptor antagonists Cimetidin and Ranitidin used for comparison. The absolute configuration of the optically active compounds 2, 3 and 4 has been determined by means of chemical correlation. The antiulcer activity of 4 is characterized by enantioselectivity, S-(+)-4 is three times as active than R-(-)-4. 相似文献
30.
BACKGROUND: Partnerships have been investigated in different professions,but other than identifying problems, little work has been carriedout on general practice. OBJECTIVE: The aim of this present study was to develop methods for studyingpartnerships in general practice. METHOD: A tripartite methodological approach was used, with questionnairesadapted from other instruments in use in other professions,followed by an individual interview with each partner, and non-participantobservation at a partnership meeting. Results for one case-studypartnership are given. RESULTS: There were no major differences between the partners on alldimensions measured; the minor differences indicated by theresults of the questionnaires were corroborated by the partnerinterviews and observations. CONCLUSIONS: We conclude that the use of such techniques could provide supportto partnerships going through significant periods of change. Keywords. General practice, interview, observation, partnerships, questionnaire. 相似文献