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排序方式: 共有1570条查询结果,搜索用时 15 毫秒
31.
David J. Kavanagh Dixie J. Statham Gerald F.X. Feeney Ross McD. Young Jon May Jackie Andrade Jason P. Connor 《Addictive behaviors》2013
Despite considerable research activity and application in treatment, the construct of craving remains poorly understood. We propose that cravings and urges are cognitive–emotional events in time, characterised by frequency, duration, intensity and salience. Commonly used measures of alcohol craving are reviewed, and their strengths and weaknesses identified. Most measures confound craving with behaviours, or with separable cognitive phenomena such as expectancies, intentions, or perceived behavioural control. These confounds have limited our advances in understanding the determinants and consequences of craving. Based on the criteria applied in this review, among the better performing multi-item measures are the Penn Alcohol Craving Scale and Obsessive subscale of the Obsessive–Compulsive Drinking Scale. Optimal assessment strategies are likely to involve daily assessments of peak intensity of cravings, desires or urges and of the frequency and duration of craving episodes. Of particular interest are measures of intensity at times when individuals are at risk of drinking or of other functional impacts from craving. 相似文献
32.
We have explored the polymorphism of the glycophorin system in the human erythrocyte membrane using the immunoblotting techniques and examining 52 individuals selected without prior bias as to their serologic state and ten documented serologic variants of M, N, S, s blood group system. Polyclonal antisera to alpha glycophorin and to alpha glycophorin CNBr carboxyl terminal fragment C (residues 82-131) and M and N specific monoclonal antibodies (MoAbs) were used. The first two reagents detect specific regions of the alpha glycophorin molecule and all electrophoretically resolved species of glycophorins immunologically related to alpha and delta glycophorins (delta glycophorin, [alpha-delta] hybrids and other glycophorins with an alteration in the carboxyl terminal segment); the M and N MoAbs identified the glycophorin species containing or lacking the M or N determinant in the amino terminal octapeptide structures. We find that immunoblotting confirmed in all cases the serologically determined phenotype; we also find that polymorphic forms of the glycophorin system are relatively infrequent; immunoblotting, independent from serologic testing, was capable of detecting five mutants, two most likely S-s-U-phenotypes; a new glycophorin species was detected in normal red cells with both antiglycophorin and antipeptide C sera, which is not evident with MoAbs; immunoblots of known glycophorin variants (En(a-), U-, Mg, Mi I, II, III, V, and Sta) confirmed but also extended our knowledge of the abnormal glycophorins involved; and the He+ and Wrb(-) cells showed normal patterns. 相似文献
33.
Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
34.
Minasian LM; Szatrowski TP; Rosenblum M; Steffens T; Morrison ME; Chapman PB; Williams L; Nathan CF; Houghton AN 《Blood》1994,83(1):56-64
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites. 相似文献
35.
Factor VIII coagulant protein (VIII:C) functions as a critical cofactor with factor IXa, calcium ions, and phospholipid during the activation of factor X. In the course of this reaction, the activity of VIII:C is first increased and then is destroyed by one or more serine proteases that are part of the coagulation sequence. In this study, we have investigated the influence of platelets on the inactivation of VIII:C by plasmin. Platelets were separated from plasma proteins in the presence of granule release inhibitors and were incubated with plasmin and isolated VIII:C or the complex of purified VIII:C/von Willebrand factor (vWF); VIII:C activity and antigen levels were assessed over time. In the presence of platelets, the isolated VIII:C showed an initial increase in VIII:C activity that was not present when platelets were absent, and the VIII:C/vWF showed an increase in VIII:C activity over that seen when platelets were absent. In addition, platelets stabilized VIII:C activity over a one-hour time course when compared with buffer. The VIII:C antigen did not increase and decreased slowly whether platelets were present or absent. Preincubating the platelets with ristocetin, collagen, or plasmin did not alter the results, and experiments using platelets from a patient with severe von Willebrand's disease also showed a pattern similar to that seen with normal platelets. Experiments using fixed platelets or phospholipid vesicles showed that they did not support the activation reaction or delay the inactivation reaction. These studies demonstrate that platelets modulate the activation and inactivation of VIII:C by plasmin, apparently by a mechanism that is independent of the platelet release reaction. 相似文献
36.
Impact of intrapeptide epitope location on CD8 T cell recognition: implications for design of overlapping peptide panels 总被引:6,自引:0,他引:6
Draenert R Brander C Yu XG Altfeld M Verrill CL Feeney ME Walker BD Goulder PJ 《AIDS (London, England)》2004,18(6):871-876
BACKGROUND: Antigen-specific CD8 T cells following infection or immunization are typically assessed by measuring interferon-gamma production after stimulation with overlapping peptides spanning the region of interest. The effect of epitope location within such peptides is not known but may influence recognition. OBJECTIVE: To examine if peptides containing the appropriate C-terminal anchor amino acid residue would provide more sensitive detection of T cell responses. The impact was examined of epitope location within overlapping peptides on recognition of epitope-specific CD8 T cell responses. METHODS: C-terminal amino acid residues were analyzed in well-defined optimal epitopes for HIV, Epstein-Barr virus, cytomegalovirus and influenza and in peptide-binding motifs. Recognition of known epitopes within longer synthesized peptides by peripheral blood mononuclear cells or CD8 T cell lines was tested using interferon-gamma Elispot at various peptide concentrations. RESULTS: Only 9 of 20 amino acids served as the C-terminal anchor position in 96% of described optimal epitopes and in 95% of peptide-binding motifs. A CD8 T cell response to an epitope within a longer peptide is best detected when the epitope is situated at the C-terminal end of the longer peptide, both when using peptides designed to include the optimal epitope at every possible position and when comparing responses towards optimal epitopes and corresponding overlapping peptides in a larger group of subjects. CONCLUSION: When using overlapping peptides to screen for CD8 T cell responses, more sensitive detection will be achieved using known C-terminal anchor amino acid residues at the C-terminus. 相似文献
37.
Judith A. Feeney 《Attachment & human development》2013,15(2):193-200
In the face of a pressing need for expanded attachment research programs and attachment informed interventions in Latin America, a research network was established: Red Iberoamericana de Apego: RIA (Iberian-American Attachment Network). The purpose of RIA is to promote human development and well being, informed by attachment theory, centering on research, and with implications for public policies, education, and intervention. We report the proceedings of the second meeting of RIA held in Panama City, Panama, in February 2010. As part of this meeting, RIA sponsored the first Latin-American attachment conference. Proceedings of the conference are described, as are future goals of this new organization. 相似文献
38.
Hematopoietic growth factor expression and ATRA sensitivity in acute promyelocytic blast cells 总被引:1,自引:0,他引:1
Dubois C; Schlageter MH; de Gentile A; Guidez F; Balitrand N; Toubert ME; Krawice I; Fenaux P; Castaigne S; Najean Y 《Blood》1994,83(11):3264-3270
Acute promyelocytic leukemia (APL) is a homogeneous subgroup of acute myeloid leukemias (AMLs) characterized by the presence of the t(15,17) translocation and the resulting promyelocytic myeloid leukemia/retinoic acid receptor alpha (PML/RAR alpha) fusion proteins. To date APL is the only AML that is sufficiently sensitive to all-trans retinoic acid's (ATRA) differentiating effect. In vivo ATRA alone achieves complete remission in most APL patients. However, failure or partial responses are observed and the molecular basis of the absence of ATRA response in these patients has not been determined. To gain insights in the cell growth and differentiation of APL cells, expression of hematopoietic growth factors (HGF) shown to be produced by leukemic cells (interleukin-1 beta [IL-1 beta], IL-6, tumor necrosis factor alpha (TNF alpha), granulocyte colony-stimulating factor [G-CSF], granulocyte- macrophage colony-stimulating factor [GM-CSF], and IL-3) was studied in 16 APL samples. Twelve APL cases expressed IL-1 beta, IL-6, and TNF alpha, but not G-CSF, GM-CSF, and IL-3. These cases achieved complete remission with ATRA therapy. The four remaining patients (either TNF alpha negative or G-CSF, GM-CSF or IL-3 positive) did not achieve complete remission with ATRA. In all cases, in vivo response to ATRA therapy was correlated to the in vitro differentiation effect of all- trans retinoic acid 10(-6) mol/L. Thus, ATRA differentiation induction was strongly correlated to the HGF expression (P < .0001). These results suggest that the presence or absence of HGF's expression by APL cells may contribute to the therapeutic effect of ATRA in this disease. 相似文献
39.
PURPOSE: We determine the main outcome effects of a 12-month computer-mediated automated interactive voice response (IVR) intervention designed to assist family caregivers managing persons with disruptive behaviors related to Alzheimer's disease (AD). DESIGN AND METHODS: We conducted a randomized controlled study of 100 caregivers, 51 in the usual care control group and 49 in the technology intervention group, who received yearlong access to an IVR-mediated system. The system provided caregiver stress monitoring and counseling information, personal voice-mail linkage to AD experts, a voice-mail telephone support group, and a distraction call for care recipients. We conducted analyses by using a repeated measures approach for longitudinal data and an intention-to-treat analytic approach. Outcomes included the caregiver's appraisal of the bothersome nature of caregiving, anxiety, depression, and mastery at baseline, 6, 12, and 18 months. RESULTS: There was a significant intervention effect as hypothesized for participants with lower mastery at baseline on all three outcomes: bother (p =.04), anxiety (p =.01), and depression (p =.007). Additionally, wives exhibited a significant intervention effect in the reduction of the bothersome nature of caregiving (p =.02). IMPLICATIONS: Wives who exhibited low mastery and high anxiety benefited the most from the automated telecare intervention. Findings suggest that, to optimize outcome effects, similar interventions should be tailored to match the users' characteristics and preferences. 相似文献
40.
Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model
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