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61.
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63.
Paul A. Obrist Richard A. Galosy James E. Lawler Claude J. Gaebelein James L. Howard Emily M. Shanks 《Psychophysiology》1975,12(4):445-455
The relationships between heart rate (HR) and several parameters of somatic activity were evaluated in human subjects when shuck avoidance was made contingent on either increases or decreases in HR. In order to depict any influence of the contingency specific 10 HR, somatic activity was controlled to varying degrees by instructions and the use of non-contingent control groups. When increases in HR were reinforced, the contingency we found to influence somatic activity but an effect specific to HR was also observed. When decreases in HR were reinforced, there was no evidence that HR were influenced independently of somatic activity. The result are discussed with respect to several current issues. 相似文献
64.
Evaluation of Hemagglutinin Protein-Specific Immunoglobulin M for Diagnosis of Measles by an Enzyme-Linked Immunosorbent Assay Based on Recombinant Protein Produced in a High-Efficiency Mammalian Expression System 下载免费PDF全文
Fabienne B. Bouche Nicolaas H. C. Brons Sophie Houard Francois Schneider Claude P. Muller 《Journal of clinical microbiology》1998,36(12):3509-3513
Recombinant hemagglutinin (H) of the measles virus (MV) expressed in a mammalian high-expression system based on the Semliki Forest virus replicon was used in an enzyme-linked immunosorbent assay (ELISA) for the detection of specific immunoglobulin M (IgM) and IgG in patients with acute-phase measles. One hundred twelve serum specimens from 70 patients with measles were analyzed. Case definition was based on a commercial IgM ELISA that utilizes MV-infected cells (MV-ELISA) (Enzygnost; Behring Diagnostics); the clinical criteria of the Centers for Disease Control and Prevention (Atlanta, Ga.); and/or the increase in hemagglutinin test titers, neutralization test titers, and levels of MV-specific IgG whenever paired sera were available. The initial time courses of the IgM signal after the onset of rash are similar in the H- and MV-ELISAs. On days 0 to 19, both ELISAs detected IgM in 67 of 68 (98.5%) sera. Average maximal levels of IgM seem to persist, however, about 10 days longer in the MV-ELISA (up to day 25) than in the H-ELISA (day 15). From days 20 to 29 and 30 to 59, the H-ELISA detected only 64.3 (9 of 14) and 19.2% (5 of 26), respectively, of sera that were IgM positive by MV-ELISA. At least up to day 30, the performance of the H-ELISA seemed to be similar to that reported for commercial ELISAs based on whole MV. Our results demonstrate that MV H-specific IgM can be used to diagnose most measles cases from a single serum specimen collected within 19 days after the onset of rash and that the recombinant protein used in this study is suitable for this purpose. 相似文献
65.
Dominique Blanchard Claude Gaillard Patrice Hermann Jacques Banchereau 《European journal of immunology》1994,24(2):330-335
In the present study, we examined the participation of CD40 ligand (L)-CD40 interaction in T cell-dependent B cell responses. To this end, purified B lymphocytes were cultured over irradiated CD4+ cloned T cells activated with immobilized anti-CD3 antibody. The anti-CD40 mAb 89 strongly blocked, in a specific fashion, both proliferation and Ig secretion of tonsil B cells. Interestingly, proliferation of surface (s)IgD+ B cell was significantly less inhibited by anti-CD40 than that of sIgD? cells. Preactivated T cells induced B cells to grow and secrete immunoglobulins preferentially in response to IL-2. This contrasts with the CD40 system where B cells are essentially responsive to IL-4 and IL-10 but not to IL-2 alone. Collectively, these data indicate that CD40L-CD40 interaction plays an important role in IL-2-mediated T cell-dependent B cell responses. However, the activation of a subset of sIgD+ cells may be independent of this interaction. 相似文献
66.
Claudia Müller Hermann Herbst Barbara Uchanska-Ziegler Andreas Ziegler Friedrich Schunter Ingeborg Steiert Claude Muller Peter Wernet 《Human immunology》1985,14(4):333-349
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6. 相似文献
67.
Summary We have analyzed the expression and function of the intron-encoded bI4 maturase when frame-shift mutations in the upstream exon alter the translational process. By constructing secondary cis-acting mutations within the b14 intron, we observed (1) that the bI4 maturase is still translated in the presence of the upstream mutation, albeit in very low amounts, and (2) that the limited amounts of bI4 maturase made under these conditions is no longer able to promote the splicing process of the aI4 intron. These observations, which further strengthen the maturase model, strongly suggest that bI4 maturase acts sequentially on the bI4 intron and then on the aI4 intron. 相似文献
68.
Jean -Paul Richalet Claude Soulard Alain Nitenberg Bernard Teisseire Jean de Bovée Sadino Séroussi 《European journal of applied physiology》1981,47(1):27-39
Summary Conditions of oxygen extraction by the myocardium have been studied in 12 subjects (44±9 years old) with pure mitral stenosis without clinical, metabolic or electrical sign of coronary insufficiency.Oxygen-hemoglobin equilibrium curves (OHEC) have been determined on arterial, mixed venous and coronary sinus blood, at rest and during a moderate (60 W, 10 min) exercise performed on a bicycle ergometer in supine position. Physiological values, at rest and during exercise, of the following functional parameters of the OHEC were determined in the in-vivo conditions of pH and PCO2P50, nHill, DS max = maximal value of OHEC slope (DS=SO2/PO2), PDS max, SDS max. The concentration of plasma electrolytes capable to modify one of these parameters was controlled in each blood sample.In coronary sinus blood, P50 rises from 27.5±1.7 to 28.9±1.6 Torr during exercise (p<0.01). At rest, Hill's n in myocardial venous blood (2.67±0.09) is significantly higher than in arterial blood (2.61±0.08, p<0.01). A decrease in DS max (2.67±0.20 to 2.53±0.12%. Torr–1; p<0.01) and an increase in PDS max (20.9±1.9 to 22.6±2.1 Torr, p<0.01) are observed. At rest, the myocardial venous point (PcsO2, ScsO2) is not significantly distinct from the maximal slope point (PDS max, SDS max). After 1 min of exercise, a small gap appears which becomes significant at the end of the exercise (PDS max-PcsO2=0.2 Torr at rest, 2.7 Torr after exercise; SDS max-ScsO2=4.1% at rest, 7.9% after exercise). DS value at the myocardial venous point is only 2% at rest and 6% after exercise, lower than its maximal value.The gap between venous point and DS max point could constitute an error signal in the regulation loop of the coronary circulation. The existence of a physiological receptor, sensitive to instant variations in myocardial tissue PO2 and able to maintain venous point near DS max point could be considered. 相似文献
69.
Lafay-Cousin L Soenen V Mazingue F Preudhomme C Laï JL Andrieux J 《Cancer Genetics and Cytogenetics》2004,150(2):153-155
Recurrent chromosomal rearrangements involving the 11q23 region have been described in various hematologic malignancies. Among these rearrangements, translocations are the most common mechanism involving the mixed lineage leukemia gene (MLL). Few cases of insertion have been reported and, to our knowledge, none of them involved MLL and chromosome 1. We report a complex karyotype in a childhood acute myelomonocytic leukemia (AML M4) involving the 11q23 region with an insertion between chromosomes 1 and 11 in addition to a translocation between chromosomes 11 and 22. This translocation was clarified by fluorescence in situ hybridization (FISH) analysis: 46,XY,ins(1;11)(q22q23;q13q23),t(11;22)(q13;q11q12). This finding also underlines the complementary contribution of conventional cytogenetic and FISH analysis to detect karyotypic complex abnormalities. 相似文献
70.
Handra-Luca A Couvelard A Sauvanet A Fléjou JF Degott C 《Virchows Archiv : an international journal of pathology》2004,445(2):203-205
We report an unusual type of mucinous cystadenoma of the pancreas, characterised by a predominantly solid gross appearance due to the presence of an abundant ovarian-type stroma. The tumour, located in the body of the pancreas, was discovered after episodes of acute pancreatitis. It was composed of several mucus-secreting benign cysts placed within a highly cellular ovarian-type stroma, composed of undifferentiated spindle cells with mild atypia but without any increase of mitotic activity and with a low proliferative index. These cells expressed oestrogen and progesterone receptors, but they did not express CD34, CD117, p53 protein or bcl-2. Recognition of this peculiar mainly solid mucinous cystadenoma containing an abundant ovarian-type stroma is difficult. It is conceivable that the mesenchymal component described in our case could represent an early stage in the development of sarcoma in mucinous cystadenoma of the pancreas. 相似文献