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1.
The presence of inflammatory reaction, plasma cells, and eosinophils in peritumoral connective tissue and in neoplastic stroma was evaluated with morphometrical method in 181 patients affected by laryngeal carcinoma. A logistic multiple regression model was applied making it with the use of an independent variable represented by the "infiltrating" or "expansive" types of tumor growth, in order to evaluate the probability of nodal metastatsis of each parameter. The results suggest an inverse correlationship between plasma cells and inflammatory infiltration and incidence of nodal metastatsis only in the comparison of the extreme conditions: those with scarce infiltration versus the ones with large infiltration. Inflammatory or plasmacellular infiltration may represent both a defense mechanism against cancer and an aspecific or allergic reaction. The eosinophilic infiltration shows no value in the prevention of nodal involvement.  相似文献   
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Summary Human epidermal keratinocytes grown in culture and at different stages of differentiation are shown to be viably separated by elutriation. A specific fraction enriched in melanocytes was obtained. Elutriation of cells obtained fromin vitro cultured epithlium could prove useful in studies concerning the biochemistry and molecular markers of cells isolated from normal epithelium and from different pathologies.  相似文献   
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The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background.  相似文献   
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At the nonpermissive temperature, somatic embryos of the temperature-sensitive (ts) carrot (Daucus carota L.) cell variant ts11 only proceed beyond the globular embryo stage in the presence of medium conditioned by wild-type cells. The causative component in the conditioned medium has been identified as an acidic 32 kD endochitinase. An antiserum raised against the 32 kD chitinase detected this protein in culture medium from ts11 embryo cultures grown at the permissive temperature as well as at the nonpermissive temperature. No difference in biochemical characteristics or in effect on ts11 embryo development could be detected between the 32 kD chitinase purified from wild-type cultures and the chitinase from ts11 cultures grown at the permissive or at the nonpermissive temperature. Compared to the amount present in a ts11 embryo culture at the permissive temperature, a reduction in the amount of 32 kD chitinase was observed during the temperature-sensitive period at the nonpermissive temperature. These results imply that the arrested embryo phenotype of ts11 is not the result of a structural difference in its 32 kD chitinase, but is the result of a transient decrease in the amount of 32 kD chitinase present. Morphological observations indicate that the ts11 phenotype is pleiotropic and also affects the cell wall of nonembryogenic cells. © 1995 Wiley-Liss, Inc.  相似文献   
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Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7.  相似文献   
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A family with a "fragile site" at 16q22, inducible by both interferon and Distamycin A, is reported. Immunological problems were found in the family. In a sibship of ten, eight children had died in infancy. Our study led to the conclusions that interferon and Distamycin A induce fragility at the same site, which has the same characteristics as the spontaneous fragile site; that a viral hypothesis for this fragility may be supported; and that immunoincompetence of one kind or another must be considered in families presenting a fragile site at 16q22.  相似文献   
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