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Fine-needle aspirates (FNAs) of 84 primary breast carcinomas were analyzed immunocytochemically for estrogen receptor (ER) using (ER-ICA) monoclonal antireceptor antibodies. ER-ICA in FNAs was concordant to ER-ICA in histologic biopsies in 87% (P less than 0.0001). In most of the carcinomas, biochemically determined ER status also correlated to ER-ICA. There was no false positive ER-ICA in FNAs compared with ER-ICA in histologic biopsies. In 11 FNAs, ER-ICA was negative, whereas it showed positivity in histologic specimens. The most frequent contributing factors to false negative ER-ICAs of FNAs were ER-ICA-low results in histologic biopsies, a prominent stroma component in these tumors, and low cellularity of FNAs. The biochemical ER values in these cases never exceeded 90 fmol/mg protein. In a minority of cases, false negative results were inexplicable.  相似文献   
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Soluble and cell-bound ligands profoundly influence the differentiative fate of lymphocytes during an immune response. Recent advances have been made in understanding the role of cytokine signals and costimulatory signals in the regulation of T cell responses associated with resistance or susceptibility to infection. There has also been recent progress in defining the requirements for the generation and maintenance of immunologic memory, a critical component of adaptive immunity.  相似文献   
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Summary Inhibitors found in certain equine sera active against poliovirus type 1 have been determined by the gel-adsorption method using aluminiumhydroxide-gel in the absence of cells. The inhibitor belongs to the 19S-class of macroglobulins (IgM), as revealed by gel-filtration with Sephadex G 200, by DEAE-cellulose-chromatography, and by sucrose density centrifugation. It is bound to the viral surface in-vitro in the absence of tissue cells. The specific complex may be precipitated with anti-equine globulin from rabbits. The inhibitor is destroyed by papain and by 2-mercapto-ethanol. The residual infectivity (10–25%) has been found bound to the inhibitor in-vitro. Its behavior in the gel-adsorption system is not altered if the virus-inhibitor complexes have previously been diluted. — Nonsensitive mutants and double mutants have been selected. There must exist at least three different combining sites for equine inhibitors on the surface of poliovirus type 1, strain Mahoney. Equine sera may be grouped according to the specificity of their inhibitory activity. The specific binding capacity is lost if the virus is heated at 50° C for 30 min.Supported by the Deutsche Forschungsgemeinschaft, Unit Medizinische Virologie; partly presented at the 5th Viruscolloquium of the Deutsche Forschungsgemeinschaft, Marburg Sept. 1965.The authors wish to acknowledge the excellent technical assistance of MissSigrid Bonk.  相似文献   
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Intracellular pathogens, particularly those that target host mononuclear phagocytes, have evolved strategies to either evade or inhibit cellular mechanisms of host defense. Mycobacterium tuberculosis and Leishmania donovani exemplify a diverse group of microorganisms that have developed the ability to invade and replicate within host macrophages, leading to disease expression. Recent studies have suggested that the pathogenesis of intracellular infection may involve interference with host cell signaling. Drawing upon examples from in vitro models that focused on M. tuberculosis and L. donovani, we review evidence that activation of host cell phosphotyrosine phosphatases may contribute to pathogenesis. A leading candidate appears to be the Src homology 2 domain containing phosphotyrosine phosphatase SHP-1, the activation of which may contribute to the development of infection and disease progression.  相似文献   
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Therapy-related acute myeloid leukemia (t-AML) characterized by the t(9;11)(p22;q23) translocation is one of the most frequent secondary malignancies. The timing of the initiation of translocation and of development of the malignant t(9;11) clone during chemotherapy is presently unknown. In the present study, we backtracked bone marrow samples from three children during treatment for acute lymphoblastic leukemia (ALL). Two patients developed a t(9;11)-positive t-AML 19 and 30 months after therapy start, whereas the third patient, diagnosed with a rare t(9;11)-positive ALL, suffered from an ALL relapse 23 months after initial diagnosis. The genomic MLL-MLLT3 (MLL-AF9) fusion site was amplified by a multiplex, nested long-range PCR and used as a clonal marker for quantification of the MLL-MLLT3-positive cells during chemotherapy. The t(9;11)-positive clone was detectable 13 and 18 months after therapy start in both t-AML cases, which was 6-12 months before clinical diagnosis of the secondary malignancy. In the t(9;11)-positive ALL patient, the identical leukemic clone reoccurred during maintenance therapy after a short molecular remission, 8 months before clinically overt ALL relapse. The time course and characteristics of the genomic breakpoints in the present t-AML cases support the hypothesis of translocation formation as a result of defective breakage repair after topoisomerase II cleavage.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Alkohol ist in Deutschland im Jugendalter die populärste Droge. Alkoholpräventionsprogramme, die im Setting Schule...  相似文献   
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Die Anaesthesiologie - In dieser Studie wurden die Studierenden der Generationen Y und Z des Studiengangs Humanmedizin an der Georg-August-Universität Göttingen...  相似文献   
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