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51.
J. Richard Eiser Joop van der Pligt Martin Raw Stephen R. Sutton 《Journal of behavioral medicine》1985,8(4):321-341
This paper reports the results of a postal questionnaire completed by 2343 smokers who had contacted a television company for help with stopping smoking. Of these, 1848 (78.9%) completed a follow-up questionnaire 1 year later. This indicated that 797 had tried to stop, 709 had tried to cut down, and 164 had become abstinent. Analyses show that the intention to try to stop smoking was dependent not only on the perceived health benefit, but also on the subjects' confidence that they would succeed if they tried to stop. As predicted by Weiner's [(1979). J. Educ. Psychol.71: 3–25] model of achievement motivation, those who attributed other smokers' failures at quitting to stable factors had lower expectancies of success, as had those who saw themselves as more addicted. When the follow-up data are considered, reported attempts at quitting were strongly related to previously declared intentions, and reported abstinence was related to previous confidence (expectancy of success) and perceived addiction. There is no support for hypotheses concerning self-other differences in attribution, or defensive attribution, in subjects' attributions for their own failures at cessation. Implications for antismoking interventions are discussed.This research was facilitated to various extents by grants from the British Council, the Department of Health and Social Security, the Medical Research Council, and the Social Science Research Council, London. When the data were collected, all authors were at the Addiction Research Unit, Institute of Psychiatry, University of London. 相似文献
52.
Mapping of a restriction fragment length polymorphism associated with defective DR beta 4 chain expression to the HLA-DRB1 gene 总被引:1,自引:0,他引:1
The HLA-DR beta 4 chain, encoded by the DRB4 gene, carries two DRw53 determinants normally expressed by DR4, DR7, and DR9 individuals. However, some DR7 individuals (DR7, Dw11) fail to express the DR beta 4 chain. At the genomic level, a HindIII restriction fragment length polymorphism can be detected in these individuals with a DR beta cDNA probe. The association of this altered HindIII fragment with defective beta 4 chain expression suggested the possibility that the polymorphic fragment was derived from the DRB4 gene and might, therefore, be related to the defect in expression. However, detailed Southern blot analysis has now mapped the polymorphic fragment to the 3' end of the DRB1 gene, approximately 100 kb away from the defective DRB4 gene. Although the alteration in the DRB1 gene might involve sequences important in regulating the expression of the DRB4 gene, it is more likely that the association results from strong positive linkage disequilibrium between these DR beta chain genes. 相似文献
53.
54.
Regulation of in vitro cytotoxic T lymphocyte generation. II. Demonstration of noncytotoxic alloantigen-specific suppressor T lymphocytes 总被引:1,自引:0,他引:1
Both allospecific suppressor T lymphocytes (TsS) and nonspecific suppressor T lymphocytes (TsN) are activated in alloantigen-stimulated mixed leukocyte cultures (MLC). TsS and TsN can suppress cytotoxic T lymphocyte (CTL) induction upon transfer to fresh (second) MLC stimulated by the same alloantigens as in the first MLC (TsS or TsN) or by third-party alloantigens (TsN only). Evidence that TsS and TsN functions are performed by different T cell sets has been restricted to radioresistance of the former but not the latter. Separation of TsS from CTL has proven even more difficult. Methods are reported here which have allowed in vitro induction and functional separation of TsS from CTL and TsN in a totally allogeneic system. TsS are resistant to combined exposure to pyrilamine, a histamine1 antagonist and local anesthetic, during suppressor cell induction, and to X or gamma irradiation thereafter, while CTL precursors (CTL-P) and TsN are more sensitive to such treatments. This allowed us to use these treatments to generate TsS that are not contaminated with functional CTL, CTL-P or TsN. These data show that TsS regulate CTL induction by interacting with responding cell populations, rather than by cytotoxic depletion of stimulator cells. 相似文献
55.
S. Vijayakumar S. F. Quadri L. Dong L. Ignacio I. N. Kathuria H. Sutton H. Halpern 《Journal of the National Medical Association》1995,87(11):813-819
This cross-sectional study was undertaken to determine whether serum hormones (free testosterone, androstenedione, luteinizing hormone, or prolactin) have any influence on serum prostate specific antigen (PSA) levels in patients with stage A-C prostate cancer. Blood samples were collected prior to any treatment in 36 patients; in 19 (group 1), three blood samples were collected 10 minutes apart between 9:00 AM and 9:30 AM for each patient and pooled together to avoid diurnal and episodic variation in serum testosterone values. In the remaining patients, only one sample could be collected (group 2). Free testosterone, androstenedione, luteinizing hormone, prolactin, and PSA levels were determined with appropriate radioimmunoassay techniques. Statistical analyses were performed separately for groups 1 and 2, and then with pooled data. None of the hormones in any of the analyses showed any association to serum PSA values except for prolactin for the pooled data and for group 2. This statistical significance for prolactin disappeared on multivariate analysis. There were 21 African-American men and 15 whites in the study; no racial differences in hormonal levels were found except for lower luteinizing hormone levels in African Americans in group 2 and pooled data. No differences were found between group 1 and group 2 in the mean serum prolactin and luteinizing hormone values. Serum free testosterone, androstenedione, and luteinizing hormone appeared to have no influence on serum PSA values in nonmetastatic cancer patients. Serum prolactin values were inversely associated with PSA values in univariate analysis for the pooled data; this disappeared in multivariate analysis. Unlike other studies that found higher serum testosterone levels in African-American college students than whites, no such differences were seen in this age group. Luteinizing hormone was lower in African-American men than in whites in the pooled study population. Further studies are needed to clarify our findings. 相似文献
56.
M Solé J Cano J L Rodríguez-Tudela J Pontón D A Sutton R Perrie J Gené V Rodríguez J Guarro 《Medical mycology》2003,41(4):293-300
Invasive infections by Scedosporium prolificans have increased alarmingly in recent years, mainly in immunosuppressed patients. The epidemiology, pathogenesis and the natural habitat of this pathogen are practically unknown. Isolates of S. prolificans were distinguished from one another by inter-simple-sequence-repeat (ISSR) fingerprinting, a technique based on the high degree of polymorphism of the multisatellite genetic markers used. This technique was found useful for typing 84 isolates of S. prolificans from different countries and sources. The assemblage of S. prolificans isolates tested was extremely diverse, with 35 genotypes present. Several patients were found to have been infected or colonized by more than one strain. Overall, this technique facilitates the epidemiological study of S. prolificans infection. 相似文献
57.
Cunliffe SL Wyer JR Sutton JK Lucas M Harcourt G Klenerman P McMichael AJ Kelleher AD 《European journal of immunology》2002,32(12):3366-3375
Reliable, efficient systems for producing soluble HLA-DR molecules, suitable for multimerization and use as staining reagents, have proved elusive. We found that the addition of a flexible linker between peptide and N terminus of the DRB1*0101-chain (Crawford, F., Kozono, H., White, J., Marrack, P. and Kappler, J., Immunity 1998. 8: 675-682.), results in greater in vitro folding efficiency of Escherichia coli-expressed alpha- and beta-chains, and increases both the yield and stability of the DRA1*0101/DRB1*0101/peptide complexes. Although a 10-amino acid linker functioned efficiently for a 20mer epitope from HIV p24, a longer linker was required to produce a DR1 MHC class II tetramer with the influenza hemagglutinin epitope (HA(306-318)). The DR1-HA tetramer was able to stain positively over 98% of a specific clone (HA 1.7) with only a brief 30-min incubation. The tetrameric complexes detected clone cells diluted into PBMC, with high sensitivity, coupled with low background staining in CD4(+) cells. It was possible to detect antigen-specific CD4(+) T cells within a population of PBMC stimulated with the HA peptide. This demonstrates the potential to monitor CD4(+) T cell responses in peripheral blood in a number of clinical scenarios. 相似文献
58.
Effects of interparental violence on the psychological adjustment and competencies of young children 总被引:8,自引:0,他引:8
J W Fantuzzo L M DePaola L Lambert T Martino G Anderson S Sutton 《Journal of consulting and clinical psychology》1991,59(2):258-265
Preschool children (N = 107) were divided into 4 groups on the basis of maternal report; home and shelter groups exposed to verbal and physical conflict, a home group exposed to verbal conflict only, and a home control group. Parental ratings of behavior problems and competencies and children's self-report data were collected. Results show that verbal conflict only was associated with a moderate level of conduct problems: verbal plus physical conflict was associated with clinical levels of conduct problems and moderate levels of emotional problems; and verbal plus physical conflict plus shelter residence was associated with clinical levels of conduct problems, higher level of emotional problems, and lower levels of social functioning and perceived maternal acceptance. Findings suggests a direct relationship between the nature of the conflict and residence and type and extent of adjustment problems. 相似文献
59.
60.
Anselmi Laura Lau Yiu-Shing Sutton Matt Everton Anna Shaw Rob Lorrimer Stephen 《The European journal of health economics》2022,23(1):133-151
The European Journal of Health Economics - Risk-adjustment models are used to predict the cost of care for patients based on their observable characteristics, and to derive efficient and equitable... 相似文献