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101.
Diarrhea is still a major cause of morbidity and mortality among children in developing countries. The Bedouin population of southern Israel is in transition from a nomadic to a settled life-style. We examined maternal knowledge and reported behavior when their children had diarrhea. Mothers defined diarrhea as the passing of 4-5 stools per day. The most frequent signs of the illness were an increased number of watery stools with changes in either color or form. The most frequent symptom that prompted mothers to seek medical aid was blood in the stool. All mothers reported increasing fluid intake in their children during diarrhea, and most reported giving herbal tea. About half of the women avoided milk products and used special foods for the treatment of diarrhea. A quarter of the women reported stopping or decreasing the frequency of breast feeding during diarrhea. Reported cessation of breast feeding during diarrhea was associated with changing to special foods, and failure to note the onset of diarrhea or to recognize signs of dehydration. The withdrawal of breast feeding during episodes of illness and diarrhea is related to lack of knowledge regarding diarrhea. These data indicate that even in this population, with free access to preventive and curative medical care, there should be greater efforts to educate mothers to detect diarrheal disease and to maintain breast feeding during the diarrhea. 相似文献
102.
IAPs comprise a family of inhibitors of apoptosis found in viruses and animals. In vivo binding studies demonstrated that both baculovirus and Drosophila IAPs physically interact with an apoptosis-inducing protein of Drosophila, Reaper (RPR), through their baculovirus IAP repeat (BIR) region. Expression of IAPs blocked RPR-induced apoptosis and resulted in the accumulation of RPR in punctate perinuclear locations which coincided with IAP localization. When expressed alone, RPR rapidly disappeared from the cells undergoing RPR-induced apoptosis. Expression of P35, a caspase inhibitor, also blocked RPR-induced apoptosis and delayed RPR decline, but RPR remained cytoplasmic in its location. Mutational analysis of RPR demonstrated that caspases were not directly responsible for RPR disappearance. The physical interaction of IAPs with RPR provides a molecular mechanism for IAP inhibition of RPR's apoptotic activity. 相似文献
103.
104.
Increasing the contrast of just one eye's image degrades stereothresholds; this phenomenon is referred to as the stereo contrast paradox. In experiment one, this paradox was found to be absent in dynamic random-element stereograms; thresholds were simply limited by the lower of the two eyes' contrasts. In experiment two, in which narrowband Gabor targets were used, the paradox was found to be strongest at relatively low spatial frequencies (1 cycle deg-1). As spatial frequency was increased, the paradox gradually disappeared. At relatively high spatial frequencies (5 cycles deg-1), thresholds were generally limited by the lower of the two eyes' contrasts, as was found for the dynamic noise targets. These results demonstrate the interactions of spatial frequency and contrast in binocular image combination and yield clues as to the different roles which high and low spatial frequencies may play in stereopsis. 相似文献
105.
106.
The effect of variations in composition on optical properties was studied. The index of refraction is lowered by the substitution of fluorine and alumina for silica; the reciprocal dispersion, however, is increased by fluorine and lowered by alumina so that fluorine and alumina can be balanced against each other to give almost any desired optical properties within the field investigated, that is, in the range of 1.46 to 1.50 for index of refraction and 63 to 70 for the reciprocal dispersion. 相似文献
107.
N. de Cediel C. G. Fraser A. Deom L. Josefsson H. G. J. Worth O. Zinder 《Journal of Automated Methods and Management in Chemistry》1989,11(3):99-105
Trainees in laboratory medicine must develop skills in laboratory
management. Guidelines are detailed for laboratory staff in
training, directors responsible for staff development and professional
bodies wishing to generate material appropriate to their
needs. The syllabus delineates the knowledge base required and
includes laboratory planning and organization, control of operations,
methodology and instrumentation, data management and
statistics, financial management, clinical use of tests, communication,
personnel management and training and research and
development. Methods for achievement of the skills required are
suggested. A bibliography of IFCC publications and other
material is provided to assist in training in laboratory management. 相似文献
108.
Eoin Cunningham Nicholas Dunne Gavin Walker Christine Maggs Ruth Wilcox Fraser Buchanan 《Journal of materials science. Materials in medicine》2010,21(8):2255-2261
The application of synthetic cancellous bone has been shown to be highly successful when its architecture mimics that of the
naturally interconnected trabeculae bone it aims to replace. The following investigation demonstrates the potential use of
marine sponges as precursors in the production of ceramic based tissue engineered bone scaffolds. Three species of natural
sponge, Dalmata Fina (Spongia officinalis Linnaeus, Adriatic Sea), Fina Silk (Spongia zimocca, Mediterranean) and Elephant Ear (Spongia agaricina, Caribbean) were selected for replication. A high solid content (80 %wt), low viscosity (126 mPas) hydroxyapatite slurry
was developed, infiltrated into each sponge species and subsequently sintered, producing a scaffold structure that replicated
pore architecture and interconnectivity of the precursor sponge. The most promising of the ceramic tissue engineered bone
scaffolds developed, Spongia agaricina replicas, demonstrated an overall porosity of 56–61% with 83% of the pores ranging between 100 and 500 μm (average pore size
349 μm) and an interconnectivity of 99.92%. 相似文献
109.
Feasibility study and tool design of using shape memory alloy as tool-structural elements for forming-error compensation in microforming 总被引:1,自引:1,他引:0
Wenke Pan Yi Qin Fraser Law Yanling Ma Andrew Brockett Neal Juster 《The International Journal of Advanced Manufacturing Technology》2008,38(3-4):393-401
Taking advantage of the special properties of shape memory alloys (SMA), a concept of error compensation for microforming with the use of SMA as an actuating/enhancing element was proposed. Simplified analysis of tool structures, FE simulation of forming processes, and experimental tests on the tubular cylinders with SMA enhancement wires showed that the pressures created due to the geometric change of the SMA under the temperature above its transformation value could generate sufficient contraction of the cylinders, compared to the forming-error values predicted for microforming, and hence, they are potentially feasible for the applications to error-compensation in microforming. Based on these results, a detailed microforming-tool design with an SMA-enhanced ring structure has been produced. 相似文献
110.