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991.
The ACTS program is moving the results of the R&D of the parent RACE program nearer to realization through technology and user trials. Particularly in the mobile domain of ACTS, several projects have been investigating the user dimension in the context of the third-generation Universal Mobile Telecommunications Service. Results so far suggest many opportunities to broaden participation, exploit the inherent benefits of the mobile environment, and take advantage of the enormous improvements in wireless communications to realize the potential of global multimedia mobility. This article considers the needs of users for mobile multimedia applications and the consequences of those needs on the equipment, supporting services and teleservices, and communications bearers  相似文献   
992.
Significative enhancement of free radical formation (FRO) in vivo is an important feature of hypertensive disorders of pregnancy (HDP), namely preeclampsia (PIH). The latest investigations about the pathology of HDP, showed the contribution of placental circulation to the development and evolution of such disease. The placental bed can be a potential source of FRO or activation of cells that can produce FRO. Glutathione, is an important molecule for cellular protection against damage, is a cofactor of many enzymes, in particular, for the glutathione peroxidase of the placental tissue; this enzyme in the placenta bed prevent the production of thromboxan and lipoperoxides; the latter are potentially damaging to the endothelium cells and can cause vasoconstriction, the most important feature of PIH. The activity of that enzyme is deficient in PIH. We studied, by fluorometric assay, the concentrations of the two states of glutathione in placental homogenates (PLH) from pregnant women without pathology (PWN) and from pregnant women with PIH (PWPIH). The data showed significant low concentrations in the PLH of the two states of glutathione in the PWN against high concentrations of this molecule in the PLH from PWPIH. This feature can result from a deficient user of the glutathione by the cellular mechanism for prevention against oxidative factors. In addition, our study shows a biochemical marker that is suggestive that the placental bed is a potential source of FRO production in PIH.  相似文献   
993.
Metal-Resistance-Semiconductor (MRS) photodetectors are characterized by a resistive layer placed in series to an avalanching region. In this paper, we report the characterization of such devices, we define a parameter extraction procedure, and we derive a quantitative model of the MRS operation. Due to the presence of the ohmic layer, the detector works as an ensemble of pixels with separately stabilized operating bias. In this way, compared to avalanche photodiodes (APDs), MRS achieve superior gain uniformity with the same sensitive area. However, there are still aspects of the fabrication technology and of the detector structure which have to be improved  相似文献   
994.
A micropower tone-control circuit comprising two first-order log-domain filters and a subtractor built with MOS transistors in weak inversion is described. The tone-controller is capable of providing bass cut/boost and treble cut operations. This circuit is being used in new designs of a conventional (acoustic) hearing-aid and cochlear implant  相似文献   
995.
Consistent efforts to identify and clinically validate new nursing diagnosis within recognized categories are essential to taxonomy development. Mixed incontinence is a clinical condition resulting in leakage of urine associated with increased intra-abdominal pressure (stress) and inability to delay voiding (urge). The presence of mixed incontinence was clinically validated in two populations (n = 9, n = 40) of community-dwelling women and initial defining characteristics were identified. Research findings from both studies support the addition of a proposed sixth nursing diagnosis, mixed incontinence, to the diagnostic category, alteration in urinary elimination.  相似文献   
996.
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   
997.
998.
The efficiency of the polymerase chain reaction (PCR) was compared with that of culture for detection of Ureaplasma urealyticum and Mycoplasma hominis in 726 clinical specimens comprising 189 gynecological samples, 362 urological samples, and 175 samples from newborn infants. The sensitivity of PCR versus culture was 95% for both organisms, while the sensitivity of culture versus PCR was 91% for Ureaplasma urealyticum and 84% for Mycoplasma hominis. Furthermore, PCR tests were faster than culture tests, allowing the time to diagnosis to be reduced from two to five days to 24 h.  相似文献   
999.
Two cases of congenital trabecular hypoplasia of the right ventricle are reported. In the first, the neonatal diagnosis was missed and the child did well until the 13th month of life when a modified Blalock-Taussig shunt was done because of increasing cyanosis. Outcome was good until the 4th year of life when symptomatic atrioventricular block was detected in an emergency situation. A bidirectional Glenn anastomosis and pacemaker implantation were successfully carried out after clinical establization and the child is doing well up to now. The second case presents the disease with its worst features: severe cyanosis and acidosis in the first day of life. A modified Blalock-Taussig shunt was performed and death occurred soon after the operation.  相似文献   
1000.
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