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81.
During the spring of 1987 and the autumn of 1988, stool specimens were collected from infants and young children in the paediatric unit at H. F. Verwoerd Hospital, Pretoria, and examined for the presence of rotaviruses to assess the potential for hospital-acquired infection in the paediatric wards. Stool samples were also collected from children admitted to the hospital for causes unrelated to gastro-enteritis to investigate the possible asymptomatic carriage of rotavirus in this population. Hospital-acquired rotavirus infection was determined in only 9% of cases. Very little asymptomatic carriage of the virus was identified. Electrophoretic analysis of the rotavirus strains showed that the majority of the infections (20 of 42) were associated with a particular strain with a long RNA profile, while 7 minor strains co-circulated (5 with a long electrophoretype and 2 with a short one). An apparent small outbreak of nosocomial infection with a single strain was observed to occur in one of the paediatric wards during the spring and early summer. 相似文献
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83.
Adverse reactions to drugs are well recognized as a cause of acute or chronic urticaria, and angio-oedema. Angiotensin-converting enzyme (ACE) inhibitors, used to treat hypertension and congestive heart failure, were introduced in Europe in the middle of the eighties, and the use of these drugs has increased progressively. Soon after the introduction of ACE inhibitors, acute bouts of angio-oedema were reported in association with the use of these drugs. We wish to draw attention to the possibility of adverse reactions to ACE inhibitors after long-term use and in patients with pre-existing angio-oedema. 相似文献
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85.
Co-aggregation (interactions between two suspended micro-organisms) between oral microbial pairs has been studied extensively and is believed to be an important factor in dental plaque formation. However, co-adhesion (interactions between suspended and already-adhering micro-organisms) may well be equally important. The aim of this paper was to determine the influence of saliva and lactose on the co-adhesion of streptococci (S. oralis 34 and S. sanguis PK1889) to actinomyces (A. naeslundii T14V-J1 or 5951) adhering on glass under flow from buffer and saliva in the absence and presence of lactose. The kinetics of co-adhesion as well as co-adhesion in a stationary end-point of co-aggregating and non-co-aggregating pairs was studied in a parallel plate flow chamber by analysis of the spatial arrangement of co-adhering micro-organisms as a function of time. For co-aggregating pairs, initial deposition rates of streptococci in the immediate vicinity of adhering actinomyces (local initial deposition rates) were up to 5 to 10 times higher than the non-local initial deposition rates in buffer and in saliva, respectively. In a stationary end-point of co-adhesion, 5 to 6 times more streptococci co-adhered with the adhering actinomyces than averaged over the entire substratum surface. A non-co-aggregating pair showed only minor preferential (co-)adhesion near the adhering actinomyces. Co-adhesion in buffer was fully lost when lactose was added. However, addition of lactose to saliva did not inhibit co-adhesion, but co-adhesion became more reversible. Detachment of micro-organisms from the substratum due to the passage of an air-liquid interface, as occurs in the oral cavity during eating, drinking, and speaking, was minimal when deposition was carried out from buffer to bare glass. Major detachment of streptococci adhering to the substratum occurred when adhesion was mediated through a salivary conditioning film on the glass, while detachment of adhering actinomyces and streptococci co-adhering with them remained low. It is suggested that, in the development of dental plaque, adhering actinomyces may act as strongholds for other micro-organisms, like streptococci, to adhere. 相似文献
86.
Describes a technique to quantify eye rotations about the visual axis (ocular torsion). Two digitized polar transformed images of the iris are displayed on a video monitor in order to facilitate a visual comparison and manual interaction. Emphasis is placed on error analysis and the method's simplicity when applied to static ocular torsion measurement. The implementation, applying averaging over ocular torsion determined in partitioned iris images, yields a theoretical resolution of 5' of arc. In a control experiment with an artificial eye, the accuracy showed to be better than 14' of arc. In practice, the measuring device was validated with the data from the literature by means of an experiment about ocular torsion in humans during tilt and hypergravity conditions (up to 3 g) 相似文献
87.
BEHAVIOUR OF AN ADIABATIC PACKED BED REACTOR PART 2: MODELLING 总被引:1,自引:0,他引:1
A. N. R. Bos L. Van De Beld H. J. Martens K. R. Westerterp 《Chemical Engineering Communications》1993,121(1):55-80
The steady state and dynamic behaviour of an adiabatic packed bed reactor for the selective hydrogenation of mixtures of ethyne and ethene is studied. A heterogeneous model with axial dispersion of heat is solved numerically by means of a fully implicit discretisation scheme. From an analysis of the inlet and outlet boundary conditions, it follows that in order to avoid an influence of the type of boundary condition on the reactor behaviour, sufficiently long inert zones before and after the active bed should be present. Using preliminary kinetic expressions adapted from Mcn'shchikov ct al. (1975), the model calculations show a reasonable agreement with the experiments performed in a laboratory scale reactor and demonstrate the importance influence of small amounts of carbon monoxide both on the steady state as well as on the transient behaviour of the reactor. However, using the rate expressions derived from our own kinetic experiments in a Berty reactor, the behaviour under runaway conditions and the transition from non-runaway to runaway conditions can not be described well. Several factors that contribute to this discrepancy are discussed. This work shows that, in particular for a complex reaction system such as the selective hydrogenation of ethyne in ethene, the limited accuracy of the kinetic model and kinetic parameters dominates the precision attainable with packed bed reactor models. 相似文献
88.
Istvan?HallerEmail author Asia?Slowinska Herbert?Bos 《Empirical Software Engineering》2016,21(3):778-810
Many existing techniques for reversing data structures in C/C ++ binaries are limited to low-level programming constructs, such as individual variables or structs. Unfortunately, without detailed information about a program's pointer structures, forensics and reverse engineering are exceedingly hard. To fill this gap, we propose MemPick, a tool that detects and classifies high-level data structures used in stripped binaries. By analyzing how links between memory objects evolve throughout the program execution, it distinguishes between many commonly used data structures, such as singly- or doubly-linked lists, many types of trees (e.g., AVL, red-black trees, B-trees), and graphs. We evaluate the technique on 10 real world applications, 4 file system implementations and 16 popular libraries. The results show that MemPick can identify the data structures with high accuracy. 相似文献
89.
Ben van Berkel Caroline Bos Astrid Piber Hannes Pfau Luis Etchegorry Hans Peter Nuenning Kristina Madsen Malaica Cimenti Veronica Baraldi Nannang Santoso Albert Gnodde Ramon van der Heijden Jeorg Lonkwitz 《城市环境设计》2010,(1):28-31
国际投资广场是北京的一个新区域,它为现代商住混合的城市提供了一个高效而可持续发展的场所。
场地位于五六环之间的亦庄经济技术开发区的核心地带。在UNStudio的总体规划中,国际投资广场的布局带有一些对中国传统生活方式的隐喻,同时也表达了保持独立性与邻里在社交相平衡的当代生活观念。 相似文献
90.
van den Bos Kees; Brockner Joel; Stein Jordan H.; Steiner Dirk D.; Van Yperen Nico W.; Dekker Daphne M. 《Canadian Metallurgical Quarterly》2010,99(4):638
In this article, we examine the hypothesis that in masculine cultures or in other contexts that emphasize competitive achievement, those with higher performance capabilities will feel empowered to have input in decisions and, hence, will desire opportunities to voice their opinions about decisions to be made. In contrast, in more feminine cultures or in other contexts that value the importance of nurturing people with lower capability, those with lower capabilities will feel valued as important group members, will feel worthy of receiving voice and, hence, will appreciate voice opportunities. We provide evidence for these predictions in 2 studies, 1 conducted in the United States (a more masculine culture) and 1 in the Netherlands (a more feminine culture). Evidence also comes from experimental conditions in both studies, in which we made salient to participants countercultural norms and values, that is, nurturing the less capable in the United States and competitive achievement in the Netherlands. Implications for the psychology of voice and cross-cultural research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献