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91.
92.
Recent cytogenetical findings and novel molecular biology results of acute myeloid leukaemia have shed new lights of our understanding in the diagnosis and treatment of the disease. Acute myeloid leukaemia is not only represented by the wide variety of morphological and immunophenotypic diversity but also demonstrates cytogenetical and molecular biological heterogeneity of its own. It has an unfavorable prognosis, especially in the elderly. Overall survival of younger patients (<50-60 years) has increased in the past years due to high dose chemotherapy (daunorubicine, cytarabine). But in case of unfavorable prognostic factors (not only cytogenetical but also molecular biological characters of the disease), allogeneic stem cell transplantation is needed for successful overall outcome. Better understanding the biology of acute myeloid leukaemia could establish novel targeted therapies and help us eventually to cure the disease.  相似文献   
93.
The cerebral cortex and liver of 20 female CFY rats of 21 months of age (at killing), kept in conventional housing conditions, were studied. Ten animals received placebo (5% gum arabic solution) and 10 other rats received 50 mg/kg body weight/day idebenone suspended in the gum arabic, through a gastric tube for 5 weeks (except Sundays). Liver and brain homogenates were obtained by homogenization of tissue pieces (10 mg/ml) in 0.32 M sucrose solution. Synaptosomal and mitochondrial fractions of the brain cortex were prepared by using established methods of density gradient centrifugation, pooling together the brains of two animals for each experiment. Protein contents of the samples were measured by means of a modified folin-phenol method. Superoxide dismutase (SOD), catalase (CA) and glutathione peroxidase (GP) activities were measured by using established biochemical methods. The activities were compared in the placebo and verum groups on a protein weight basis. The SOD activity increased slightly (but not significantly) in the total brain homogenate, whereas both the mitochondrial and synaptosomal fractions of the cortex displayed significant increases of this enzyme activity (28.5 and 16.3% respectively). SOD and CA activities decreased in the liver homogenate and all other parameters remained invariate both in the brain and its subfractions, except CA in the synaptosomal fraction where a slight decrease occurred (-15.6%).  相似文献   
94.
The analytical system used for determination of 22 illicit and licit drugs by gas chromatography–mass spectrometry following liquid–liquid extraction has been extended with an additional extraction step with n-butyl acetate:CH2Cl2 = 1:8 to determine benzoylecgonine from the same oral fluid, blood, or urine samples. The extraction recovery of benzoylecgonine was 39.7% for oral fluid, 14.9% for blood, and 26.7% for urine; the cutoffs were 25, 8.0, and 8.0 ng/ml, respectively. The method was fully validated and proved suitable in further proficiency tests and for analysis of 2738 oral fluid, 197 blood, and 1298 urine samples.  相似文献   
95.
Magnesium sheet metal alloys offer a deformation asymmetry, which is strongly related to grain size and texture. In order to predict deformation behavior as well as to provide methods to eliminate anisotropy and yield asymmetry, a lot of effort is invested in studying the tension–compression asymmetry of magnesium alloys. However, only a few studies deal with the characterization of the yield asymmetry of magnesium wrought alloys, especially Ca-containing alloys, related to temperature and strain. In this study, the orthotropic behavior of a twin-roll-cast, homogenized, rolled and finish-annealed Mg-2Zn-1Al-0.3Ca (ZAX210) magnesium alloy was investigated by tensile testing at room temperature, 150 °C and 250 °C. The r-values were determined and the Hill’48 yield criterion was used for the constitutive formulation of the plastic yielding and deformation. The yield loci calculated using Mises and Hill’48 as well as the determined r-values reveal an almost isotropic behavior of the ZAX210 alloy. The r-value increases with increasing logarithmic strain. At 0.16 logarithmic strain the r-values at room temperature vary between 1 (0°) and 1.5 (45° and 90°). At higher temperatures (250 °C), r-values close to 1 at all tested directions are attained. The enhanced yield asymmetry can be attributed to the weaker basal texture that arises during hot rolling and final annealing of the twin-roll-cast ZAX210 magnesium alloy. In comparison to AZ31, the ZAX210 alloy shows a yield behavior close to transversal isotropy. Finally, responsible mechanisms for this behavior are discussed.  相似文献   
96.
PROBLEM: Anterior dislocation of the articular disk of the temporomandibular joint (TMJ) found by MRI tomography often presents a problem. It may persist in MRI despite improvement of articular symptoms and even be found in healthy persons free of any symptoms. Can this be explained by the similarity in structure of the anterior connective tissue of the disk and capsule and their pathological changes? Is a second coronal plane required for MRI investigation? MATERIAL AND METHODS: The preauricular regions of 72 patients of the TMJ clinic were examined by oblique-sagittal and oblique-coronal MRI. A Siemens-Vision MRI was used. It was also possible to prepare 10 articular disks of the TMJ with anterior capsular tissue as well as 20 complete TMJs of adults from autopsy material. Sagittal, transversal, and horizontal serial sections were examined histologically. RESULTS: In 49 of the 72 cases examined, an anterior dislocation without reduction found in the sagittal MRI was not confirmed in the oblique-coronal MRI. In the sagittal MRI it was possible to differentiate three, in the coronal MRI six typical forms of magnetic resonance signals, which are represented in figures. They are compared with anatomical and histological connective tissue findings adjacent to the TMJ. The structural similarity of the disk and anterior capsular tissue of the TMJ is demonstrated. The close connection of the disk and connective tissue surrounding the TMJ makes differentiation of MRI findings difficult especially following regressive and adaptive reactions. CONCLUSIONS: In MRI, anterior capsular tissue is able to simulate dislocation of the disk. Pathological tissue reactions may alter the MRI signal and lead to the wrong diagnosis of dislocation of the disk. Diagnosis of an anterior disk dislocation cannot be established solely on the basis of oblique-sagittal MRI findings.  相似文献   
97.
The thyroid gland is often injured by supradiaphragmatic irradiation for Hodgkin's lymphoma. The aim of the present study was to examine whether the parathyroid gland gets injured by the treatment for Hodgkin's disease. Calcium, phosphorus and parathormone levels of 143 patients with primary treatment for Hodgkin's disease and in complete remission for 2 years were measured as well as the presence of antiparathyroid antibody in patients having antithyroid antibody. Out of the 143 patients studied, 104 received neck irradiation (with or without chemotherapy); among them laboratory alterations were observed in 7 cases. 39 patients received only chemotherapy; 3 of them had alterations. In contrast to the injury of the thyroid gland, no damage to the parathyroid glands associated with the treatment for Hodgkin's disease was noted. It has been concluded that the use of high-dose external radiotherapy does not mean a higher risk as regards the parathyroid gland but further follow-up studies of the patients may result in the revelation of the development of parathyroid lesions.  相似文献   
98.
The functions of friction and adhesion in the processing of solid materials were evaluated in our work. The second part of our study dealt with some practical examples from our practice. Indomethacin was used for the examination of adhesion, dimenhydrinate for the study of friction, and metronidazole for the determination of the spreading coefficient. Several technological methods (coating, granulation, pelletization and tableting) were used. The positive effects of the processes on the various phenomena (surface free energy, adhesion force and spreading coefficient) were emphasized. The influences of alteration in the parameters on the flowability, compressibility, compact texture, etc. were assessed.  相似文献   
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