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91.
Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients.  相似文献   
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Mice of the BALB/c strain are widely used in behavioral research in spite of the albino condition, which can obscure brain-behavior relationships. We have developed a pigmented BALB strain, congenic to BALB/c, which could be more appropriate for neurogenetic studies that aim at identifying the effects of neurological mutations on behavior. Comparison of inbred albino and pigmented congenic BALB arising from the same litters provides a valuable tool for detecting the consequences of the albino mutation on behavioral performances. Preliminary results presented here show that the albino condition does not interfere with the development and patterns of connectivity of mossy fibers in the hippocampus. On the other hand, obvious coat color-linked differences appear for locomotor activity and defecation scores in the open field, pigmented mice being unexpectedlyl less active and more reactive than albino, as if better vision increased their reactions to a novel, anxiogenic environment. Finally, pigmented mice do not show better performances in the radial maze, which confirms that the inability of BALB mice for spatial learning in a highly demanding version of this task cannot be attributed to their inability to process visual information.  相似文献   
95.
A yellow-pigmented coryneform rod was isolated from the blood of a child with acute lymphoblastic leukemia who was perfused with a central venous catheter. The culture bottles were positive twice, at a 2-month interval. The isolate was identified as a Microbacterium sp. and studied along with five other similar strains. Phenotypic, chemotaxonomic, and genetic characteristics indicated that they are closely related to Microbacterium oxydans but that they belong to a distinct species, for which the name Microbacterium paraoxydans sp. nov. is proposed. The type strain of M. paraoxydans is CF36(T) = DSM 15019(T). The G+C content of its DNA is 69.9 mol%.  相似文献   
96.
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors.  相似文献   
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Geant4 application for tomographic emission (GATE) is a recently developed simulation platform based on Geant4, specifically designed for PET and SPECT studies. In this paper we present validation results of GATE based on the comparison of simulations against experimental data, acquired with a standard SPECT camera. The most important components of the scintillation camera were modelled. The photoelectric effect. Compton and Rayleigh scatter are included in the gamma transport process. Special attention was paid to the processes involved in the collimator: scatter, penetration and lead fluorescence. A LEHR and a MEGP collimator were modelled as closely as possible to their shape and dimensions. In the validation study, we compared the simulated and measured energy spectra of different isotopes: 99mTc, 22Na, 57Co and 67Ga. The sensitivity was evaluated by using sources at varying distances from the detector surface. Scatter component analysis was performed in different energy windows at different distances from the detector and for different attenuation geometries. Spatial resolution was evaluated using a 99mTc source at various distances. Overall results showed very good agreement between the acquisitions and the simulations. The clinical usefulness of GATE depends on its ability to use voxelized datasets. Therefore, a clinical extension was written so that digital patient data can be read in by the simulator as a source distribution or as an attenuating geometry. Following this validation we modelled two additional camera designs: the Beacon transmission device for attenuation correction and the Solstice scanner prototype with a rotating collimator. For the first setup a scatter analysis was performed and for the latter design. the simulated sensitivity results were compared against theoretical predictions. Both case studies demonstrated the flexibility and accuracy of GATE and exemplified its potential benefits in protocol optimization and in system design.  相似文献   
99.
Twenty-four acromegalic patients were treated with octreotide subcutaneously for periods of 3 to 6 weeks (group I, 12 cases) or 6 months (group II, 12 cases) before transsphenoidal surgery. Radiological studies performed in 19 patients before and at the end of this treatment period revealed no changes in 8 cases. In 8 other cases, a slight reduction in tumorsize was observed, and in 3 cases an important shrinkage was documented. At surgery, the adenomatous tissue appeared softer than in nonpretreated patients, facilitating the operation. Pathological examination revealed widening of perivascular spaces with accumulation of fibrous tissue and more crinophagy than in nonpretreated patients but failed to reveal morphologically pronounced cell involution as observed in prolactin-producing adenomas treated with dopamine agonists. No significant difference in frequency or extent of cellular changes was noted between the two groups. These morphological findings seem to be more consistent with a functional inhibition of growth hormone release than with cellular alterations induced by octreotide.  相似文献   
100.
The members of the joint group "Toxicology and Clinical Biology" of the French Society of Clinical Biology (SFBC), the French Society of Analytical Toxicology (SFTA), and the Society of Clinical Toxicology (STC), suggest guidelines to meet the requirements of clinical biologists who are not specialized in toxicology. Based on good laboratory practice they propose a number of guidelines. Three synthetic tables have been established. They are not only toxicity biomarkers and metabolic disorders associated with the main severe intoxications, but also clinical signs that are observed during these intoxications, finally biological sampling as a precautionary measure. The table also takes into account approximately fifty xenobiotics: main clinical signs emergency, identification or quantification of the suspected product, useful biological markers, therapeutic, quantitations necessary to take into consideration patient care, and poison antidotes, are described. Recommendations regarding medical and forensic techniques are also proposed by the group. It is also necessary to collect and store biological samples when the individual patients are in charge. These samples will be analyzed or not depending on the individual case history.  相似文献   
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