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51.
We studied the efficacy of sequential intravenous-oral pefloxacin therapy in community-acquired lower respiratory tract infection in 24 patients with one or more underlying conditions. Twenty-eight patients were enrolled into the study but only 24 patients were evaluated. There were 16 males and 8 females with a mean age of 66.9 +/- 11.2 years (mean +/- SD, range 46 to 87 years). The underlying conditions present were bronchiectasis, chronic obstructive lung disease and diabetes mellitus. Patients who were older than 70 years but without any underlying condition were also enrolled. All received 4 days of intravenous pefloxacin 400 mg twice a day followed by oral pefloxacin 400 mg twice a day for another 10 days. Assessment of success was based on clinical, microbiological and radiological improvement. Pefloxacin produced 79.2% clinical cure rate. Another 8.3% showed improvement. Pefloxacin was well tolerated. There were few adverse effects and none of the patients required a change of antibiotic. Pefloxacin was an effective and well tolerated treatment for respiratory tract infection and had the advantage of broad in-vitro antibacterial activity, twice daily dosing and sequential availability in an intravenous and oral formulation. 相似文献
52.
This report demonstrates how to calculate distances between points described in terms of latitude and longitude, using the Postal Code Conversion File (PCCF) and other files available from the Geography Division of Statistics Canada. Examples based on hospital data show how the results can be summarized in the form of tables, figures, or maps. Aerial distance to the nearest hospital is a crude but objective indicator of geographic accessibility to hospital services. Distances were calculated between enumeration area centroids for the population and blockface or enumeration area centroids for the hospitals. The median aerial distance to the nearest hospital facility in Canada was less than 3 km, while the mean distance was about 6 km. For teaching hospitals, the median aerial distance was a little less than 30 km, while the mean distance was a little more than 90 km. As most health files for administrative and research purposes contain postal codes, these techniques have potentially wide application. 相似文献
53.
An early step in the development of vertebrae, ribs, muscle, and dermis is the differentiation of the somitic mesoderm into dermomyotome dorsally and sclerotome ventrally. To analyze this process, we have developed an in vitro assay for somitic mesoderm differentiation. We show that sclerotomal markers can be induced by a diffusible factor secreted by notochord and floor plate and that heterologous cells expressing Sonic hedgehog (shh/vhh-1) mimic this effect. In contrast, expression of dermomyotomal markers can be caused by a contact-dependent signal from surface ectoderm and a diffusible signal from dorsal neural tube. Our results extend previous studies by suggesting that dorsoventral patterning of somites involves the coordinate action of multiple dorsalizing and ventralizing signals and that a diffusible form of Shh/Vhh-1 mediates sclerotome induction. 相似文献
54.
In this report, the role of 34 kDa HA-binding protein in hyaluronic acid-induced cellular signalling in lymphocytes has been examined. The binding of 125I-HA to lymphocytes in vivo was found to be inhibited by pre-incubation of the cells with anti-34 kDa HA-binding protein antibodies, thus confirming 34 kDa HA-binding protein as the specific HA-receptor in lymphocytes. This observation was substantiated by anti-34 kDa HA-binding protein antibodies immunoblotting and 125I-HA ligand blotting of lymphocytes cell lysate. The HA-induced cell aggregation, tyrosine phosphorylation and cytoskeletal protein phosphorylation demonstrate the HA-induced early cellular signalling events in lymphocytes. Further, to study the involvement of 34 kDa HA-binding protein in mitogen induced lymphocyte signalling, we studied in vivo phosphorylation and secondary messenger formation. The enhanced 34 kDa HA-binding protein phosphorylation by HA and the inhibition of cellular aggregation and IP3 formation by anti-HA-binding protein antibodies revealed that 34 kDa HA-binding protein is one of the potential mediators in HA-induced signal transduction. 相似文献
55.
Significant amounts of bismuth can be removed from magnesium-lead alloys by crystallization of the intermetallic compounds
Mg0. 6573Pb0. 3427 and Mg0.662Pb0.338in the Mg2Pb, magnesium plumbide phase field of the Pb-Mg-Bi system. The results of the previous studies have been used to develop a
process for debismuthizing lead using controlled conditions for the crystallization of magnesium plumbide from alloys containing
0.03 to 0.06 wt Pct bismuth and magnesium whose concentration is determined by the relationship wt Pct Mg = 2.9 + 20 x wt
Pct Bi. A flow diagram showing the sequence of operations is presented together with a material balance, which was established
from data obtained from individual experiments simulating the previously mentioned unit operations, with a final product containing
less than 0.0010 wt Pct Bi. The process also includes the recycling of magnesium recovered by vacuum distillation. Additional
procedures are included to extend the process to treat alloys containing up to 1.5 wt pct bismuth. 相似文献
56.
The experience of our 16 patients treated for membranous duodenal stenosis is reported. Their treatment and course was analysed in a retrospective study. Eight patients were operated on within the first 16 days of life and in the remaining group surgery was performed at 1 month to 4 y of age. The presenting symptom leading to diagnosis was, in all but one case, non-bile-stained vomiting. Associated malformations were found in all but four patients, mostly morbus Down. The operative procedure performed was a partial excision of the duodenal membrane and a duodenoplasty in 10 patients, a duodenojejunostomy in 5 patients, and a duodenoplasty only in 1 patient. The postoperative course was without lethal complications. One late stricture in an anastomosis occurred. We conclude that in its presentation, duodenal stenosis differs from duodenal atresia, and can often be misinterpreted, resulting in a late diagnosis, and should be reported as a separate entity. 相似文献
57.
58.
A set of chaotic attractors is observed on a boost converter model. The union of their Poincare maps is strange. The attractors are densely packed such that they are sensitive to initial conditions. However every attractor in the set is stable with a finite (may be long) period 相似文献
59.
60.
This paper investigates the effect of the waterproofing sleeve on the calibration of kilovoltage photon beams (50-300 kV). The sleeve effect correction factor, ps has been calculated using the Monte Carlo method as the ratios of the air kerma in an air cavity of a cylindrical chamber without the waterproofing sleeve to that with a sleeve. Three sleeve materials have been studied, PMMA, nylon and polystyrene. The calculations were carried out using the EGS4 (Electron Gamma Shower version 4) code system with the application of a correlated-sampling variance-reduction technique. The results show that the sleeve correction factor for 1-mm thick nylon and polystyrene sleeves, ps varies from 0.992 to 1.000 and from 0.981 to 1.000, respectively, for the same beam quality range. The ps factor varies with sleeve thickness, beam quality and phantom depth. No significant dependence of the ps factor on field size and source-surface distance has been found. Measurements for PMMA, nylon and polystyrene sleeves of various thicknesses have also been carried out and show excellent agreement with Monte Carlo calculations. 相似文献