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41.
Chronic myeloid leukemia course was evaluated versus sex in 271 patients. Chronic stage involved more pronounced leukocytosis, thrombocytosis and splenomegaly in females, the latter showing higher susceptibility to anemia. As a result, treatment has to deal with a greater mass of tumor. A relatively longer survival time in males (44 and 42 months, respectively) suggest a higher effectiveness of therapy in such patients. When diagnosed, leukocytosis, thrombocytosis, enhanced splenomegaly and anemia should be regarded as factors of unfavorable prognosis.  相似文献   
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43.
Biodegradable substrates and encapsulating materials play critical roles in the development of an emerging class of semiconductor technology, generally referred as “transient electronics”, whose key characteristic is an ability to dissolve completely, in a controlled manner, upon immersion in ground water or biofluids. The results presented here introduce the use of thin foils of Mo, Fe, W, or Zn as biodegradable substrates and silicate spin‐on‐glass (SOG) materials as insulating and encapsulating layers, with demonstrations of transient active (diode and transistor) and passive (capacitor and inductor) electronic components. Complete measurements of electrical characteristics demonstrate that the device performance can reach levels comparable to those possible with conventional, nontransient materials. Dissolution kinetics of the foils and cytotoxicity tests of the SOG yield information relevant to use in transient electronics for temporary biomedical implants, resorbable environmental monitors, and reduced waste consumer electronics.  相似文献   
44.
The corrosion inhibition of Al-Alloy (Al2024) in 0.5 M nitric acid solution at 30 °C was achieved using 4-4-dimethyloxazolidine-2-thione (DMT) as a corrosion inhibitor. The electrochemical performance of the DMT was studied by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization measurements, and scanning electron microscopic study (SEM). The results indicated that DMT acts as an inhibitor for Al2024 in 0.5 M nitric acid. Polarization curves indicated that DMT was a mixed-type inhibitor. Inhibition efficiencies were observed to be increased with an increase in DMT concentration and attains approximately to 93.4% at 2 mM of DMT in 0.5 M nitric acid. The adsorption of DMT model on Al2024 surface obeyed in accordance with Langmuir adsorption isotherm model. The value of the free energy of adsorption ΔG ads indicated that the adsorption of DMT molecule was a spontaneous process and was typical of physical and chemical adsorption.  相似文献   
45.
The effects of doping of MgAl2O4 by a binary mixture of Co and Zn ions on the absorbance, electrical resistivity, capacitance, thermal conductivity, heat capacity and thermal diffusivity are reported in this paper. The materials with the nominal composition Mg1−2x(Co,Zn)xAl2O4 (x = 0.0-0.5) are synthesized by solution combustion synthesis assisted by microwave irradiation. The substituted spinels are produced with a Scherrer crystallite size of 18-23 nm, as opposed to 45 nm for undoped samples, indicated by X-ray diffraction and confirmed by transmission electron microscopy. These materials also show better thermal stability in the temperature range of 298-1773 K. Three strong absorption bands at 536, 577 and 630 nm are observed for the doped samples which are attributed to the three spin allowed (4A2 (F) → 4T1 (P)) electronic transitions of Co2+ at tetrahedral lattice sites while pure magnesium aluminate remains transparent in the whole spectral range. The semiconducting behavior of the materials is evident from the temperature dependence of the electrical resistivity. Resistivity and activation energy are higher for the substituted samples. Fitting of the resistivity data is achieved according to the hopping polaron model of solids. Both dielectric constant and loss increase on account of doping. The dielectric data are explained on the basis of space charge polarization. The thermal conductivity and diffusivity are lowered and the heat capacity is increased in the doped materials. Wiedemann-Franz's law is used to compute the electronic and lattice contributions towards the total thermal conductivity.  相似文献   
46.
The yield of upper gastrointestinal endoscopy (esophago-gastroduodenoscopy; EGD) in human immunodeficiency virus (HIV)-infected patients based on presenting symptoms has not been well studied. We studied consecutive patients with documented HIV infection undergoing EGD at a large innercity hospital between August 1, 1990 and December 31, 1993; all had presenting symptoms and indications for EGD prospectively recorded at the time of EGD. All endoscopic abnormalities were routinely subjected to biopsy, and extensive histopathological evaluation was performed. EGD was considered helpful when the findings stimulated specific therapeutic intervention other than antifungal or antacid medications. The specific indications for EGD in 156 patients were as follows: esophageal symptoms, 102 patients (65%); abdominal pain, 18 (12%); upper gastrointestinal bleeding, 25 (16%); refractory nausea and vomiting, 11 (7%). Overall, pathologic findings were identified in 116 patients (74%): in refractory esophageal symptoms, 82%; upper gastrointestinal bleeding, 92%; abdominal pain, 39%; nausea and vomiting, 27%. EGD with biopsy identified a specifically treatable opportunistic disorder other than Candida in 80 patients (51%), including idiopathic esophageal ulcer (22%) or viral esophagitis and/or duodenitis (29%). EGD was not helpful in 22.3% of cases, those involving Candida (12.3%) and peptic ulcer disease (PUD)-related causes (10%). The mean CD4 count of patients with opportunistic pathologic findings (24/mm3, n = 79) was significantly lower than that of patients with PUD/gastroesophageal reflux disease (GERD) (167/mm3, n = 9) or negative EGDs (165/mm3, n = 35). Overall, the results of EGD influenced patient management in 78% of cases. We conclude that selective symptom-specific use of EGD, particularly in patients with esophageal symptoms refractory to antifungal therapy or gastrointestinal bleeding, usually identifies specifically treatable abnormalities, whereas EGD is less useful for the evaluation of abdominal pain or nausea and vomiting.  相似文献   
47.
This study reports on a detailed clinical, electrophysiological, muscle computed tomography (CT) and laboratory investigation carried out on five families with definite linkage to chromosome 2p. Some clinical and laboratory features were common to most of the patients, such as the very high serum creatine kinase (CK) levels (mean 43.70 times the normal). The onset was most frequently in the late teens or early twenties with weakness and wasting of the pelvic girdle muscles. All patients had normal motor milestones and had not complained of any symptoms of muscle disease in early childhood. The clinical course was variable both between and within some families, but was most often slowly progressive. Some variability in the pattern of muscle involvement between the different families has also been observed.  相似文献   
48.
The limb-girdle muscular dystrophies are a clinically and genetically heterogeneous group of disorders. We have studied two large inbred families of different ethnic origin and excluded linkage to LGMD2 on chromosome 15q and SCARMD on chromosome 13. Proceeding to a genomic linkage search, we have now identified linkage to markers D2S134 and D2S136 on chromosome 2p (maximum lod score 3.57 at zero recombination). The phenotype in the two families was similar, with onset in the pelvic girdle musculature in the late teens and usually relatively slow progression. This work identifies a second locus for autosomal recessive limb-girdle muscular dystrophy.  相似文献   
49.
Selective epitaxial growth (SEG) of silicon has not had widespread use as a dielectric isolation technology due to the near sidewall defects at the SiO2/Si interface. These defects are located in the first 1-2 μm of the SEG/sidewall SiO2 interface. Diode junctions intersecting the sidewall and 5 μm removed from the sidewall were fabricated in SEG material using thermally grown silicon dioxide (OX) and thermally nitrided thermal silicon dioxide (NOX) as the field insulating mask. Averaged over 16 devices of each type, diodes fabricated with NOX had much better low current I-V characteristics and minimum ideality factors (1.03) than diodes fabricated with OX field oxides (1.23). Junctions intersecting the NOX field insulator had nearly identical characteristics to bulk SEG  相似文献   
50.
The performance of communications networks can be monitored intrusively by transmitting test packets on the network links being tested. The delays experienced by these test packets and the number of test packets lost or duplicated may provide an indication of the performance of the links being monitored. Intrusive network monitoring, even at modest sampling rates, generates a significantly large amount of primitive data. This data needs to be summarised appropriately to address the required network performance analysis operations. These operations are generally iterative in nature, where the results of initial processing and analysis generate requirements for further processing and analysis. This paper describes the architecture of a database that can assist in efficient analysis of network performance by reusing the information derived at various stages.  相似文献   
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