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31.
Analysis of T cell activation with a non-mitogenic anti CD3 antibody and the phorbol ester TPA. 总被引:2,自引:0,他引:2
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We used a non mitogenic anti CD3 antibody, termed VIT3, to study the signals required for the activation of normal resting T lymphocytes. Besides being not mitogenic, this antibody completely inhibits mitogen induced proliferative responses. In the presence of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), however, VIT3 induces DNA replication and cell proliferation comparable to PHA responses. In addition, T cells cultured with VIT3 plus TPA but not with VIT3 or TPA alone express high levels of interleukin 2 (IL-2) receptors and transferrin receptors. This co-stimulation appears to be accessory cell independent. Purified T cells respond equally well to VIT3 plus TPA as do unseparated mononuclear cells and addition of non-T cells has no enhancing effect. We conclude that the IgM antibody VIT3, although non-mitogenic by itself, still delivers a first and for the activation essential signal. In resting T cells this signal does not induce demonstrable anti-Tac antibody binding nor does it lead to a fully developed proliferative response in the presence of recombinant IL-2. Together with a second signal provided by TPA it serves, however, as a potent inducer of T cell growth. 相似文献
32.
Immunosuppressive effects of (2R,5R)-6-heptyne-2,5-diamine an inhibitor of polyamine synthesis: I. Effects on mitogen-induced immunoglobulin production in human cultured lymphocytes.
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J L Pasquali P S Mamont A Weryha A M Knapp A Blervaque M Siat 《Clinical and experimental immunology》1988,72(1):141-144
The consequences of specific inhibition of polyamine biosynthesis by (2R,5R)-6-heptyne-2,5-diamine (MAP) a potent inhibitor of L-ornithine decarboxylase (ODC), on immunoglobulin (Ig) production were studied in cultured human peripheral blood lymphocytes stimulated with pokeweed mitogen (PWM). MAP inhibits the usual PWM-induced increase of polyamine (putrescine, spermidine and spermine) concentrations and reduces concomitantly cell replication. In parallel with these biochemical effects, IgG and IgM production are diminished, a 95% decrease being observed at 100 microM MAP concentration. That the suppressive effects of the ODC inhibitor result from polyamine deficiency, and not from unrelated pharmacological effects, is demonstrated by the restoration of normal Ig production when 10 microM putrescine or spermidine are added to the culture medium. These findings established that the cellular immunological response can be affected by specific inhibition of polyamine biosynthesis and deserve further consideration both under in vitro and in vivo conditions. 相似文献
33.
A new distribution record is established for the tick Ornithodoros kelleyi Cooley & Kohls for Kentucky. Collections of this tick were associated with bat roosting sites in attics of houses. Scanning electron microscopy was used as an aid in distinguishing various taxonomic characteristics and morphological structures of O. kelleyi. 相似文献
34.
Risk of localized and widespread endometrial cancer in relation to recent and discontinued use of conjugated estrogens 总被引:13,自引:0,他引:13
S Shapiro J P Kelly L Rosenberg D W Kaufman S P Helmrich N B Rosenshein J L Lewis R C Knapp P D Stolley D Schottenfeld 《The New England journal of medicine》1985,313(16):969-972
In a case-control study of the risk of adenocarcinoma of the endometrium in relation to conjugated-estrogen use, we found that 31 per cent of 425 women with endometrial cancer and 15 per cent of 792 controls reported having used conjugated estrogens; the rate-ratio estimate was 3.5 with a 95 per cent confidence interval of 2.6 to 4.7. For use that lasted at least one year, the rate-ratio estimate for Stage I or II cancer was 5.2 (95 per cent confidence interval, 3.7 to 7.2), and for Stages III and IV combined it was 3.1 (1.5 to 6.4). Among women who had used estrogen for at least one year and then discontinued it, the risk of endometrial cancer remained significantly elevated even after estrogen-free intervals of over 10 years. The findings suggest that long-term use of conjugated estrogen increases the risk of both localized and widespread endometrial cancer. The data also suggest that women who have taken conjugated estrogen for one or more years remain at increased risk for at least 10 years after they discontinue use. Such women should be considered for long-term gynecologic surveillance. 相似文献
35.
Tyrer P Thompson S Schmidt U Jones V Knapp M Davidson K Catalan J Airlie J Baxter S Byford S Byrne G Cameron S Caplan R Cooper S Ferguson B Freeman C Frost S Godley J Greenshields J Henderson J Holden N Keech P Kim L Logan K Manley C MacLeod A Murphy R Patience L Ramsay L De Munroz S Scott J Seivewright H Sivakumar K Tata P Thornton S Ukoumunne OC Wessely S 《Psychological medicine》2003,33(6):969-976
BACKGROUND: We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD: Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS: Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION: Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined. 相似文献
36.
W. Knapp 《Medical microbiology and immunology》1960,146(4):315-330
Zusammenfassung Außer den schon bekannten antigenen Beziehungen zwischen Past. pseudotuberculosis und der Salmonella-Gruppe bestehen Partialgemeinschaften zwischen 1. Past. pseudotuberculosis Typ II und O-Faktor 27 der Salmonella-B-Untergruppe und 2. Past. pseudotuberculosis Typ IV und den O-Faktoren 46 bzw. 14 der Salmonella-Untergruppen D2 und H. Die antigene Beziehung zur Salmonella-H-Untergruppe ist aber nur schwach ausgeprägt.Bei Past. pseudotuberculosis Typ IV wurden die Subtypen A und B nachgewiesen. Zum Subtyp A gehören die Stämme 32 IV und 190 IV, während dem Subtyp B die bisher serologisch nicht typisierten Past. pseudotuberculosis-Stämme Ikegaki und Saisawa, deren serologisches Verhalten aber nicht in allen Einzelheiten geklärt ist, zugerechnet wurden.Die Ergebnisse der verschiedenen Versuchsreihen wurden am Ende der jeweiligen Abschnitte eingehend besprochen. 相似文献
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39.
This article reviews the legal and ethical issues that arise in the treatment of patients who may pose a threat to harm themselves or others. The recent practice of developing empirically validated treatments has not yet been applied to the diagnosis and treatment of patients who present an imminent danger of harm to themselves or others. Instead, psychologists must follow standards that come primarily from court cases or statutes. Although these standards have some degree of commonality across North America, psychologists are encouraged to be informed about local laws and court cases. 相似文献
40.
Rohrmeier T Putzhammer A Schoeler A Sartor H Dallinger P Nöthen MM Propping P Knapp M Albus M Borrmann M Knothe K Kreiner R Franzek E Lichtermann D Rietschel M Maier W Klein HE Eichhammer P 《Psychiatric genetics》1999,9(4):169-175
hSKCa3 is a neuronal small conductance calcium-activated potassium channel, which contains a polyglutamine tract, encoded by a polymorphic CAG repeat in the gene. Since an association between longer alleles of this CAG repeat and bipolar disorder or schizophrenia has been reported, we genotyped the polymorphic CAG repeat in 91 German family trios of patients with bipolar disorder I and used the transmission disequilibrium test (TDT) to test for association. Applying a dichotomized model (< or = 19 or > 19 CAG triplets), we found no evidence for an association of longer alleles with bipolar disorder (TDT = 0.75, P = 0.386). Regarding the whole range of alleles, there was no preference in transmitting the larger of the two observed alleles from parents to the affected offspring. In parallel we performed an independent case-control study on German patients with bipolar disorder and schizophrenia. Again we did not detect an overrepresentation of longer CAG repeats in patients. Thus, our data do not support the hypothesis that longer CAG repeats in the hSkCa3 gene contribute to the susceptibility for bipolar disorder and schizophrenia. 相似文献