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991.
Three years after receiving rubella vaccine, 1,060 elementary school children living on the island of Maui, Hawaii, were revaccinated with either HPV-77 DE-5 or RA 27/3 rubella vaccine given subcutaneously or intranasally in order to compare the effectiveness of these two vaccines in raising antibody titers. RA 27/3 was the more effective booster vaccine, producing fourfold or greater titer rises in 20.1% of recipients, including 80% of children with hemagglutination-inhibiting antibody titers less than or equal to 1:40 at the time of revaccination, intranasal revaccination was not significantly more effective than subcutaneous revaccination, although it did elicit higher titers in children who responded. Responses differed according to the vaccine that children had received three years earlier. Because antibody titers have persisted in vaccinated children, routine administration of a second dose of rubella vaccine is not currently recommended.  相似文献   
992.
A simple left-heart assist device was developed to reduce left ventricular preload while simultaneously increasing total systemic blood flow. It consists of special cannulas connected to a simple extracorporeal tubing loop and roller pump, designed to permit bypass of as much as 5 liters of blood per minute from left atrium to ascending aorta. Employed in 15 patients with advanced heart disease who were in low cardiac output following repair, the system was proven effective. An asset of the device is the ability to subsequently separate the patient from the device without need to reenter the thorax or abdomen.  相似文献   
993.
The authors describe the radiographic appearance of several commonly used rectal suppositories. Such drugs are sufficiently opaque to be seen on abdominal radiographs and may simulate excreted urographic contrast medium or stones. Errors in interpretation can be avoided by asking the patient about rectal medication or by taking lateral or delayed films.  相似文献   
994.
To test the hypotheses that people believe that certain kinds and styles of clothing are indicative of liberal sexual attitudes and behavior and these beliefs are correct, questionnaires were filled out by 259 subjects. These questionnaires asked each subject for the frequencies with which he wore various items and styles of clothing, his attitude toward premarital sexual relations, the number of persons with whom he had had sexual relations, the frequencies with which he believed sexually liberal men and women wore various items and styles of clothing, and the frequencies with which he felt sexually conservative men and women wore various items and styles of clothing. Correlations showed that, although subjects believed that a large number of items and styles of clothing are indicative of liberal sexual attitudes and behavior, only a few items and styles actually were associated with liberal sexual attitudes and reported behavior.  相似文献   
995.
996.
Halothane concentrations of 2 p.p.m. have been found in the breast milk of a lactating, practising anaesthetist. This concentration was consistent with the operating theatre environment. The authors fell that, in spite of the limited scope of the study, this is an additional reason for the elimination of waste anaesthetic agents from the operating theatre.  相似文献   
997.
In this study, the formation of Fe18Cr8MnxN alloys by mechanical alloying (MA) of the elemental powder mixtures was investigated by running the milling process under nitrogen and argon gas atmospheres. The effect of the milling atmosphere on the microstructure and phase contents of the as-milled powders was evaluated by X-ray diffraction and transmission electron microscopy. The thermal behavior of the alloyed powders was also studied by differential scanning calorimetry. The results revealed that in the samples milled under nitrogen, three different phases, namely ferrite (α), austenite (γ), and a considerable amount of amorphous phase are present in the microstructure. In contrast, in the samples milled under argon, the structure contains the dominant crystalline ferrite phase. By progression of MA under the nitrogen atmosphere, the ferrite-to-austenite phase transformation occurs; meanwhile, the quantity and stability of the amorphous phase increase, becoming the dominant phase after 72 h and approaching 83.7 wt% within 144 h. The quantitative results also showed that by increasing the milling time, grain refinement occurs more significantly under the nitrogen atmosphere. It was realized that the infused nitrogen atoms enhance the grain refinement phenomenon and act as the main cause of the amorphization and α-to-γ phase transformation during MA. It was also found out that the dissolved nitrogen atoms suppress the crystallization of the amorphous phase during the heating cycle, thereby improving the thermal stability of the amorphous phase.  相似文献   
998.
New methods for fabrication of 3D macroporous carbon scaffolds and synthesis of mesopores on carbon surfaces are proposed. Ordered macroporous filamentary carbon structures were made by rapid prototyping using solvent-based extrusion freeforming which allows the scaffold to be designed on computer and downloaded directly to a building platform. The surface of extruded filaments was decorated with 20?C25?nm open mesopores by coating with nano-silica as a hard template followed by pyrolysis and dissolution of the silica. This left an open mesoporous surface to serve as a host for catalysts or enzymes while retaining integrity in the core for electrical and mechanical performance. The combination of these two methods could be used to make different hierarchical, multi-functional carbon structures which could be applied in fuel cells as the catalyst carrier and biofuel cell electrode.  相似文献   
999.
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We define the notions of strong and strict recurrency for actions of countable ordered groups on σ-finite non atomic measure spaces with quasi-invariant measures. We show that strong recurrency is equivalent to non existence of weakly wandering sets of positive measure. We also show that for certain p.m.p ergodic actions the system is not strictly recurrent, which shows that strong and strict recurrency are not equivalent.https://doi.org/10.1051/ita/2023001  相似文献   
1000.
The use of groundwater with high fluoride concentrations poses a health threat to millions of people around the world. This study aims at providing a global overview of potentially fluoride-rich groundwaters by modeling fluoride concentration. A large database of worldwide fluoride concentrations as well as available information on related environmental factors such as soil properties, geological settings, and climatic and topographical information on a global scale have all been used in the model. The modeling approach combines geochemical knowledge with statistical methods to devise a rule-based statistical procedure, which divides the world into 8 different "process regions". For each region a separate predictive model was constructed. The end result is a global probability map of fluoride concentration in the groundwater. Comparisons of the modeled and measured data indicate that 60-70% of the fluoride variation could be explained by the models in six process regions, while in two process regions only 30% of the variation in the measured data was explained. Furthermore, the global probability map corresponded well with fluorotic areas described in the international literature. Although the probability map should not replace fluoride testing, it can give a first indication of possible contamination and thus may support the planning process of new drinking water projects.  相似文献   
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