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991.
We employ diffuse optical tomography (DOT) to track treatment progress in a female subject presenting with locally advanced invasive carcinoma of the breast during neoadjuvant chemotherapy. Three-dimensional images of total hemoglobin concentration and scattering identified the tumor. Our measurements reveal tumor shrinkage during the course of chemotherapy, in reasonable agreement with magnetic resonance images of the same subject. A decrease in total hemoglobin concentration contrast between tumor and normal tissue was also observed over time. The results demonstrate the potential of DOT for measuring physiological parameters of breast lesions during chemotherapy.  相似文献   
992.
To verify the changes of mesopic and photopic contrast sensitivity function of sound eye whose visual acuity was kept the same after occlusion therapy in the amblyopic children. Fourteen sound eyes of amblyopic children (mean; 7.67 years; S.D., 1.50 years) who kept their visual acuity the same after the occlusion therapy were tested. The children had 6 hours of part-time patch therapy for 3 months prior to this examination. Among 14 amblyopic children, 8 were anisometric and 6 were strabismic amblyopes. Using the visual capacity analyzer which measures the minimal contrast level at from low to high spatial frequencies, the contrast sensitivity of sound eye was measured, under both photopic and mesopic condition, before and after 3 months of occlusion therapy. Comparing the contrast sensitivity of sound eye after the occlusion therapy to that before the occlusion, there was no statistical difference in photopic condition. When it comes to mesopic condition, the contrast sensitivity decreased at the intermediate spatial frequency level (3-13 c.p.d, p=0.028) after the occlusion therapy. The occlusion caused statistically significant decrease in mesopic contrast sensitivity, when the visual acuity was not changed after the occlusion therapy. It may indicate that mesopic contrast sensitivity can be considered as a useful tool for early detection of hidden occlusion amblyopia.  相似文献   
993.
994.
Biphenotypic acute leukemias account for 4% to 8% of all acute leukemias. Most of these leukemias are of myeloid-B-cell or myeloid-T-cell lineage. Acute myeloid-natural killer cell leukemia has been recognized recently. We report the first case, to our knowledge, of CD56(+) acute leukemia showing unequivocal myeloid and B-cell differentiation in a 20-year-old woman, whose blast cells were positive for myeloperoxidase, CD13, CD33, CD117, terminal deoxynucleotidyl transferase, CD19, CD20, CD22, CD34, HLA-DR, and CD56 but negative for CD3, CD5, CD7, and CD10. Rare Auer rods were identified in the blast cells. Polymerase chain reaction assays showed rearrangement of immunoglobulin heavy-chain gene and absence of Epstein-Barr virus DNA. We propose that this novel form of multilineage leukemia may represent the neoplastic counterpart of a progenitor that can give rise to myeloid, B, and natural killer cells.  相似文献   
995.
BACKGROUND: To assess the nature and prevalence of skin disorders among psychiatric patients on chronic lithium therapy and to compare them with patients on other psychotropic medications. METHOD: 51 patients on lithium and 57 patients on other psychotropics were recruited. Dermatological assessment included a semi-structured questionnaire and clinical examination of the subjects by two dermatologists who were blind to the psychiatric diagnosis and treatment. Secondary cutaneous reaction was defined as skin eruption that developed or deteriorated after commencement of psychiatric medication. RESULTS: Lithium treated patients developed significantly more secondary cutaneous reactions than the control group. This applied particularly to acne and psoriasis. Male patients on lithium were more likely to be affected than female patients. CONCLUSION: Lithium aggravates or triggers cutaneous conditions that are characterized by the pathological findings of neutrophilic infiltration. Since these cutaneous problem can be distressing to patients and may affect medication compliance, there should be heightened attention to skin problems in patients receiving lithium treatment.  相似文献   
996.
The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy  相似文献   
997.
Human monocytes released superoxide anion, prostaglandin E2, leukotriene B4, IL-1, and TNF when exposed to plastic surfaces coated with murine anti-CD3 monoclonal antibody, OKT 3. Stimulation of mediator release by OKT 3 was dependent on the amount of antibody immobilized onto wells of plastic tissue culture plates. Soluble antibody or antibody adsorbed to monocytes and reacted with an aggregating (cross-linking) second antibody failed to induce mediator release. Monocytes armed with OKT 3 formed rosettes with T cells in a fashion indistinguishable from that seen between monocytes and T cells sensitized with OKT 3. Monocytes with adsorbed OKT 3 antibodies released IL-1 and TNF- when exposed to unsensitized T cells, although increased superoxide release could not be detected. OKT 4a, a murine IgG2a antibody that reacts with a different T cell epitope (CD4), failed to induce cytokine release from monocytes when cross-linked by T cells or a CD4+ T cell line, even in the presence of IL-2 or IFN-. These data indicate that certain antibodies bound to Fc receptors (FcR) of monocytes may trigger monocyte function when reacting with cells bearing the appropriate target antigens. FcR-mediated signaling resulting in mediator release may be involved in initiating or regulating the immune response. Furthermore, systemically administered monoclonal antibodies may induce inflammatory responses and their attendant symptomatologies via their interaction with FcR-bearing inflammatory cells.  相似文献   
998.
Sitosterolaemia (also known as phytosterolaemia, MIM 210250) is a rare recessive autosomal inherited disorder, characterised by the presence of tendon and tuberous xanthomas, accelerated atherosclerosis and premature coronary artery disease. The defective gene is hypothesised to play an important role in regulating dietary sterol absorption and biliary secretion, thus defining a molecular mechanism whereby this physiological process is carried out. The disease locus was localised previously to chromosome 2p21, in a 15 cM interval between microsatellite markers D2S1788 and D2S1352 (based upon 10 families, maximum lodscore 4.49). In this study, we have extended these studies to include 30 families assembled from around the world. A maximum multipoint lodscore of 11.49 was obtained for marker D2S2998. Homozygosity and haplotype sharing was identified in probands from non-consanguineous marriages from a number of families, strongly supporting the existence of a founder effect among various populations. Additionally, based upon both genealogies, as well as genotyping, two Amish/Mennonite families, that were previously thought not to be related, appear to indicate a founder effect in this population as well. Using both homozygosity mapping, as well as informative recombination events, the sitosterolaemia gene is located at a region defined by markers D2S2294 and Afm210xe9, a distance of less than 2 cM.  相似文献   
999.
1000.
Brain kinases may play important roles in normal memory as well as in the pathogenesis of neurodegenerative diseases. However, there is scant information on these enzymes in the human brain. For this reason, we characterized the immunohistochemical localization of protein kinase C (PKC) isozymes in human Alzheimer's disease (AD) and non-AD control brains. Using monoclonal antibodies to PKC alpha, PKC beta, and PKC gamma isozymes, we (a) determined the distribution of each PKC isozyme in eight different brain regions (cerebellum, hippocampus, as well as midfrontal, orbital frontal, motor, occipital, parietal, and temporal cortices) from AD and non-AD control brains and found that these patterns were generally similar to those in the rat brain; (b) showed that there were no significant differences in the normal staining intensity of the monoclonal antibodies in AD and non-AD control brain regions except in the hippocampus; (c) observed striking PKC immunoreactivity in globular and linear profiles in the periphery (corona) of AD senile plaques; and (d) demonstrated that PKC alpha immunoreactivity was enhanced in reactive astrocytes associated with senile plaques and other lesions (embolic infarcts) in both AD and non-AD control brains. The data on the normal distribution of each PKC isozyme were corroborated in quantitative studies of PKC alpha, PKC beta, and PKC gamma protein levels in human postmortem brain regions by Western blotting using our antibodies. We conclude that these three major PKC isozymes can be analyzed directly in postmortem human brain, which is an important first step in understanding the potential role that abnormal phosphorylation might play in the pathogenesis of AD.  相似文献   
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