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31.
32.
Patients with acute myelocytic leukemia (AML) have varied outlooks for survival after the diagnosis. To identify pretreatment prognostic indicators in AML, we analyzed 132 cases of AML seen at our hospital between June, 1989 and December, 1994. The median age of the patients was 40 years (range, 15-81). There were 63 male and 69 female patients. One hundred eight patients (82%) received induction chemotherapy which was based on cytarabine plus anthracyclines. Sixty six patients achieved complete remission (CR) and the CR rate among the patients given induction chemotherapy was 61%. The median duration of CR was 11.2 months. After median follow up of 6.6 months (range 0.5-51.4), 26 patients (39%) remain in continuous CR. The median duration of overall survival of the patients was 6.7 months. After median follow up of 10.6 months (range, 0.1-52.7), 41 patients (31%) are alive. Variables affecting duration of CR included the age of the patients, performance status of the patients, percentage of blast in the peripheral blood, hemoglobin level, percentage of blast in the bone marrow, FAB subtype, and CD7 marker positivity. Variables affecting survival duration included age of the patients, performance status of the patients, absolute blast count (ABC) in the peripheral blood, bone marrow cellularity, the percentage of blast in the bone marrow, and CD5 marker positivity. Multivariate analysis showed that the age of the patients and percentage of blast in the bone marrow were significant independent indicators for overall survival of the patients. Further studies utilizing cytogenetics and molecular characteristics of leukemic cell are warranted to better define the prognostic factors of patients with AML.  相似文献   
33.
In this paper, a distributed measurement of the chromatic dispersion (CD) of an optical fiber is presented. The measurement is based on the analysis of a set of bidirectional optical time domain reflectometer traces collected over the wavelength range of interest. To calculate the distributed CD of the fiber, several approximations are required. The validity of these approximations is verified via a numerical simulation for both step-index and dispersion-shifted fibers (DSFs). These simulations allow the placement of an upper bound on the error of the measurement. Experimentally, measurements of both step-index and DSFs are reported.  相似文献   
34.
The functioning of the major subsystems of the speech production apparatus of a 12 year old female with Moebius syndrome was investigated using a battery of perceptual and physiological instrumental measures. Perceptual tests administered included: The Assessment of Intelligibility of Dysarthric Speech; the Frenchay Dysarthria Assessment; and a perceptual analysis of a speech sample based on a reading of the Grandfather Passage. Instrumental procedures included: spirometric and kinematic analysis of speech breathing; electroglottographic and aerodynamic evaluation of laryngeal function; nasometric assessment of velopharyngeal function; and evaluation of lip and tongue function using a variety of strain-gauge and pressure transducers. Consistent with the pathophysiological basis of Moebius syndrome, the major dysfunctions of the speech production mechanism were found at the level of the articulatory valve. Somewhat unexpectedly, however, impaired function was also identified at the level of the velopharyngeal and laryngeal valves by both the perceptual and instrumental assessments and at the level of the respiratory system by the physiological analysis alone. The results are discussed with reference to the neurological basis and clinical features of Moebius syndrome. The implications of the findings for the treatment of congenital dysarthria associated with Moebius syndrome are also discussed. The advantage of instrumental analysis over perceptual assessments in defining treatment goals for children with congenital dysarthria is highlighted.  相似文献   
35.
Gram-positive anaerobic cocci (GPAC) are a heterogeneous group of organisms defined by their morphological appearance and their inability to grow in the presence of oxygen; most clinical isolates are identified to species in the genus Peptostreptococcus. GPAC are part of the normal flora of all mucocutaneous surfaces and are often isolated from infections such as deep organ abscesses, obstetric and gynecological sepsis, and intraoral infections. They have been little studied for several reasons, which include an inadequate classification, difficulties with laboratory identification, and the mixed nature of the infections from which they are usually isolated. Nucleic acid studies indicate that the classification is in need of radical revision at the genus level. Several species of Peptostreptococcus have recently been described, but others still await formal recognition. Identification has been based on carbohydrate fermentation tests, but most GPAC are asaccharolytic and use the products of protein degradation for their metabolism; the introduction of commercially available preformed enzyme kits affords a physiologically more appropriate method of identification, which is simple and relatively rapid and can be used in routine diagnostic laboratories. Recent reports have documented the isolation in pure culture of several species, notably Peptostreptococcus magnus, from serious infections. Studies of P. magnus have elucidated several virulence factors which correlate with the site of infection, and reveal some similarities to Staphylococcus aureus. P. micros is a strongly proteolytic species; it is increasingly recognized as an important pathogen in intraoral infections, particularly periodontitis, and mixed anaerobic deep-organ abscesses. Comparison of antibiotic susceptibility patterns reveals major differences between species. Penicillins are the antibiotics of choice, although some strains of P. anaerobius show broad-spectrum beta-lactam resistance.  相似文献   
36.
To accommodate the proliferation of heterogeneous network models and protocols, the use of semantic technologies to enable an abstract treatment of networks is proposed. Network adapters are employed to lift network specific data into a semantic representation. Semantic reasoning integrates the disparate network models and protocols into a common data model by making intelligent inferences from low‐level network and device details. Automatic discovery of new devices, monitoring of device state, and invocation of device actions in a generic fashion that is agnostic of network types is enabled. A prototype system called SNoMAC is described that employs the proposed approach operating over UPnP, TR‐069, and heterogeneous sensors. These sensors are integrated by means of a sensor middleware named SIXTH that augments the capabilities of SNoMAC to allow for intelligent management and configuration of a wide variety of sensor devices. A major benefit of this approach is that the addition of new models, protocols, or sensor types merely involves the development of a new network adapter based on an ontology. Additionally, the semantic representation of the network and associated data allows for a variety of client interfaces to facilitate human input to the management and monitoring of the system.  相似文献   
37.
Five bituminous coals, an anthracite and a lignite have been flash-pyrolysed by the electrically-heated grid technique or by means of an electrically-heated fluidized-bed. In the experiments using a heated grid, data were obtained on rates of rapid devolatilization and on the composition of the gases and tars evolved with heating rates up to 3000 Ks?1 and peak temperatures up to 1400 K. Similar, but more limited data were obtained using the fluidized-bed system. Mathematical models based on overall single- or two-reaction pathways were compared with the experimental results. Good agreement could be achieved by the latter with activation energies of 16 and 35 kJ mol?1.  相似文献   
38.
The relationship between Doppler measurements, size and growth rate in fetal growth restriction has not been defined. We used functional linear discriminant analysis (FLDA) to investigate these parameters taking account of the difficulties inherent in exploring relationships between repeated observations from a small number of cases. In 40 fetuses with severe growth restriction, serial abdominal circumference (AC), umbilical, middle cerebral artery (MCA) and ductus venosus Doppler pulsatility index measurements were recorded. In 11 singleton fetuses with normal growth, umbilical artery pulsatility index only was measured. Data were expressed as z-scores in relation to gestation and analysed longitudinally using FLDA. In severe growth restriction, the Spearman correlation coefficients between umbilical artery pulsatility index and AC z-score, MCA pulsatility index and AC z-score and ductus venosus pulsatility index z-score and AC z-score were, respectively: −0.36, p = 4.4 × 10−7; 0.70, p = 1.1 × 10−17 and −0.50, p = 8.1 × 10−4. No relationship was seen between Doppler parameters and growth rate. There was no relationship between umbilical artery pulsatility index and AC nor growth rate in normally grown fetuses. In severe fetal growth restriction, Doppler changes are related to absolute fetal AC size, not growth rate.  相似文献   
39.
Abstract— Organic‐light‐emitting‐diode (OLED) displays employing white‐light‐emitting OLEDs in combination with RGBW color filters can demand high peak currents to present images with bright, highly saturated colors. Image‐processing methods that take advantage of a very highly efficient white subpixel in addition to filtered RGB subpixels to reduce the peak current and power of these displays are described. The image‐quality impact of these algorithms are explored to develop a final image‐processing algorithm.  相似文献   
40.

The results of several research field studies were evaluated to estimate the precision and bias of various designated PM2.5 Federal Reference Method (FRM) samplers. Precision was favorable in these carefully conducted research studies where all operational activities were strictly controlled, with an average coefficient of variation (CV) ranging from 2 to 6%. No significant bias was found between the method designations. Comparisons between the designated reference method samplers meet the EPA Equivalent Method Criteria for comparability except for one pair of samplers. In this instance, the  相似文献   
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