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151.
Biorobotics is a promising new area of research at the interface between biology and robotics. Robots can either be used as physical models of biological systems or be directly inspired by biological studies. A great deal of progress has recently been made in biorobotic studies of locomotion, orientation, and vertebrate arm control.  相似文献   
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Chromosome band 11q23 is frequently involved in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) de novo, as well as in myelodysplastic syndromes (MDS) and lymphoma. Five percent to 15% of patients treated with chemotherapy for a primary neoplasm develop therapy-related AML (t-AML) that may show rearrangements, usually translocations involving band 11q23 or, less often, 21q22. These leukemias develop after a relatively short latent period and often follow the use of drugs that inhibit the activity of DNA-topoisomerase II (topo II). We previously identified a gene, MLL (myeloid-lymphoid leukemia or mixed-lineage leukemia), at 11q23 that is involved in the de novo leukemias. We have studied 17 patients with t-MDS/t-AML, 12 of whom had cytogenetically detectable 11q23 rearrangements. Ten of the 12 t-AML patients had received topo II inhibitors and 9 of these, all with balanced translocations of 11q23, had MLL rearrangements on Southern blot analysis. None of the patients who had not received topo II inhibitors showed an MLL rearrangement. Of the 5 patients lacking 11q23 rearrangements, some of whom had monoblastic features, none had an MLL rearrangement, although 4 had received topo II inhibitors. Our study indicates that the MLL gene rearrangements are similar both in AML that develops de novo and in t-AML. The association of exposure to topo II-reactive chemotherapy with 11q23 rearrangements involving the MLL gene in t-AML suggests that topo II may play a role in the aberrant recombination events that occur in this region both in AML de novo and in t-AML.  相似文献   
155.
The pattern of c-erbB-3 gene product was studied in 91 advanced gastric carcinomas, adjacent hyperplastic mucosa, intestinal metaplasia and dysplasia and in normal controls, using immunohistochemistry in archival material. All tumours showed positive c-erbB-3 staining in both cytoplasm and membrane. No significant differences of expression were observed between intestinal and diffuse-type carcinomas or any other clinical parameters. Of interest is the expression in the adjacent mucosa, which is extensive, cytoplasmic, and of lower intensity than in the tumours. Further studies are currently being carried out to clarify the role of this protein in tumour behaviour and gastric carcinogenesis.  相似文献   
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Forty-four patients underwent bipedal lymphography for evaluation of fever of unexplained origin, or because a malignant tumor (usually lymphoma) was suspected clinically. Extensive prior medical evaluation was inconclusive. The lymphograms were of no apparent value in detecting the etiology of the illness. Reactive follicular hyperplasia was frequently seen and sometimes simulated lymphoma on the lymphogram. The primary value of lymphography in such cases is as an aid in planning biopsy and surgery.  相似文献   
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Historically colostrum and milk have been thought to confer immunity on the neonate only by virtue of their immunoglobulin content. Recently we have observed that colostrum also contains viable T lymphocytes capable of expressing cell-mediated immunity in vitro and have employed techniques of lymphocyte culture to elucidate the local nature of mammary tissue immunity at the T-cell level. The results indicate that the activity of colostral lymphocytes appears not to represent the total immunological experience of the mother but that they may contain reactive clones beneficial for the suckling. Colostral immunity appears to depend upon sensitizing events within the intestine and respiratory tract, followed by the migration of lymphoid precursors to the breast, suggesting a relationship between the expression of immunity at various secretory surfaces.  相似文献   
159.
Kombucha tea is an alternative therapy that is gaining popularity as a remedy for a diverse range of ailments. We report two cases of symptomatic lead poisoning requiring chelation therapy in a married couple who had been drinking Kombucha tea for six months, brewing the tea in a ceramic pot. We postulate that acids in the tea eluted lead from the glaze pigment used in the ceramic pot, in a manner analogous to elution of lead from crystal decanters by wine and spirits.  相似文献   
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