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排序方式: 共有409条查询结果,搜索用时 15 毫秒
101.
Immunoglobulin and T cell receptor gene rearrangements in human lymphoma and leukemia 总被引:6,自引:0,他引:6
Williams ME; Innes DJ Jr; Borowitz MJ; Lovell MA; Swerdlow SH; Hurtubise PE; Brynes RK; Chan WC; Byrne GE Jr; Whitcomb CC 《Blood》1987,69(1):79-86
DNA samples from blood leukocytes or tumor biopsies of 45 patients with phenotypic B or T cell neoplasms were analyzed for rearrangements of the immunoglobulin (Ig) or T cell receptor (TCR) genes by Southern blot hybridization analysis. Rearrangements of the Ig heavy chain joining region genes (JH) were present in DNA from each of 28 B cell lymphomas and leukemias; 14 of 21 of these tumors also had rearrangements of the Ig kappa light chain joining (JK) or deleting element (KDel) genes. Conversely, 16 of 17 T cell lymphomas and leukemias had rearranged TCR beta chain genes. One B cell and one T cell tumor had rearrangements of both Ig and TCR genes. There was a strong correlation between the rearrangements of specific genes and the immunophenotype of the tumor: JH rearrangement without TCR beta chain rearrangement occurred only in B cell tumors; TCR beta chain rearrangement with or without JH rearrangement occurred only in T cell tumors, with one exception; and JK and KDel rearrangements were found only in B cell tumors. Thus, rearrangements of the Ig heavy and light chain genes and the TCR beta chain genes were found to be highly sensitive markers of monoclonal human lymphomas and lymphoid leukemias, with the type of gene rearrangements well correlated with the cell lineage of these neoplasms. 相似文献
102.
Urba WJ; Baseler MW; Kopp WC; Steis RG; Clark JW; Smith JW d; Coggin DL; Longo DL 《Blood》1989,73(1):38-46
Immune function in patients with hairy cell leukemia (HCL) was examined serially during treatment with alternating monthly cycles of recombinant interferon alpha-2a and 2'-deoxycoformycin (dCF). At presentation, most patients had normal numbers of T lymphocytes and their cells had normal proliferative responses to mitogens [phytohemagglutinin (PHA) and concanavalin A (Con A)] and alloantigens. Patients had severe monocytopenia, decreased delayed-type hypersensitivity (DTH) reactions, and decreased peripheral blood natural killer (NK) activity. Treatment caused a profound decrease in all lymphocyte subpopulations. T cells were more affected than B cells or NK cells. Numbers of CD4+ and CD8+ lymphocytes decreased to levels less than 200 cells/microliters in all patients during treatment. This decrease in T cell number was associated with a marked decrease in proliferative responsiveness to PHA, Con A, and alloantigens. These abnormalities persisted throughout the 14 months of treatment and have continued for up to 6 months beyond discontinuation of treatment. NK cell activity increased during treatment, but cycled depending on the phase of treatment; highest activities were observed after interferon (IFN)-alpha and lower levels of activity were observed after dCF. DTH responses generally did not improve during therapy. Levels of IgM, IgG, IgA, and IgD did not change during treatment, but IgE levels rose in most patients. All immunosuppressive effects were attributable to dCF since patients receiving IFN-alpha 2a alone did not exhibit these same immunosuppressive effects, and patients receiving dCF alone after IFN failure exhibited similar abnormalities. Despite this severe immunosuppression from dCF, life-threatening opportunistic infections have not been observed in our patient population. Six patients developed localized Herpes zoster infection among 21 patients who had received dCF. Pending the results of long-term follow-up, we recommend that dCF be reserved for patients who have failed splenectomy and IFN therapy. 相似文献
103.
A 43-year-old male with a phenotypically homogeneous, expanded subset of T cells presented in 1981 with anemia and neutropenia. The surface antigen phenotype of 99% of the peripheral blood lymphocytes was T3+, T8+, T4-, and they were morphologically large granular lymphocytes (LGL). The same cells comprised 37% of the marrow nucleated cells. Eight months after he presented, the peripheral blood T8+, LGL diminished spontaneously, and the anemia and neutropenia completely resolved. The patient remains hematologically normal as of October 1984. To determine if the T8+, LGL represented a clonal expansion, DNA from peripheral blood lymphocytes collected and cryopreserved when the patient was neutropenic and anemic, and when he was hematologically normal, was analyzed for clonal T-cell antigen receptor gene rearrangements. Using Southern blot analysis, a clonal DNA rearrangement was demonstrated, and this clone diminished but was still demonstrable in peripheral blood lymphocytes collected in 1984. The above observations implicate the expanded T8+, LGL in the pathogenesis of the neutropenia and anemia, yet the exact mechanism remains to be elucidated. 相似文献
104.
Lymphocyte predominance Hodgkin's disease: lineage and clonality determination using a single-cell assay 总被引:4,自引:1,他引:4
Lymphocyte predominance Hodgkin's disease (LPHD) is a clinically indolent condition. Although there is evidence that the putative neoplastic cell in this disease, the "L&H" cell, is of B-cell lineage, there is conflicting data concerning the clonality of these cells. Our study was aimed at clarifying the issue of lineage and clonality of the L&H cells of LPHD using a single-cell assay. Four cases of LPHD were studied. To circumvent the difficulties of obtaining fresh tissue and to be able to study representative cases, a new method was developed to obtain single-cell suspensions of L&H cells from archival formalin- fixed paraffin-embedded tissue. Single L&H cells were identified by morphology and immunostaining for epithelial membrane antigen, isolated using a micropipette, and subjected to polymerase chain reaction (PCR) amplification of the complematarity determining region 3 (CDR3) of the Ig heavy chain (IgH) gene, which is B-cell clone-specific. The PCR products were size-fractionated by polyacrylamide gel electrophoresis and representative products were directly sequenced. Single T cells and small B cells were also isolated from the tissues and used as negative and positive controls, respectively. In all four cases of LPHD, the IgH CDR3 of single L&H cells could be amplified. Within each case, the IgH CDR3 of single L&H cells was found to be of different length or of different sequence. Therefore, our results provide strong evidence for the B-cell origin of the L&H cells and the polyclonal nature of LPHD. 相似文献
105.
Edmond?SK?MaEmail author Chris?LP?Wong Kristi?TW?Lai Edmond?CH?Chan WC?Yam Angus?CW?Chan 《BMC infectious diseases》2005,5(1):60
Background
Kocuria, previously classified into the genus of Micrococcus, is commonly found on human skin. Two species, K. rosea and K. kristinae, are etiologically associated with catheter-related bacteremia. 相似文献106.
Nichols WC; Cooney KA; Mohlke KL; Ballew JD; Yang A; Bruck ME; Reddington M; Novak EK; Swank RT; Ginsburg D 《Blood》1994,83(11):3225-3231
An animal model for human type I von Willebrand disease (vWD) has been previously described in the inbred mouse strain RIIIS/J. Murine vWD is characterized by a prolonged bleeding time, normal von Willebrand factor (vWF) multimer distribution, autosomal dominant inheritance, and proportionately decreased plasma vWF antigen, ristocetin cofactor, and factor VIII (FVIII) activities. To study the molecular genetics of murine vWD, a portion of the vWF gene surrounding exon 28 was cloned, sequenced, and used to develop two informative DNA sequence polymorphisms for rapid genotyping by DNA polymerase chain reaction. RIIIS/J mice were crossed with PWK/Ph mice, an inbred line of Mus musculus musculus, and the F1 progeny backcrossed to the parental PWK/Ph strain. vWF antigen levels in F1 mice were not significantly different from the parental RIIIS/J strain but were markedly decreased compared with the parental PWK/Ph mice. Genetic linkage analysis of 104 backcross progeny showed no correlation between vWF antigen level and vWF genotype. These data indicate that murine vWD is caused by a defect at a novel genetic locus, distinct from the murine vWF gene. The distribution of vWF antigen levels among backcross progeny suggests the presence of one major dominant vWD gene in the RIIIS/J mouse with possible modifying contributions from one or more additional minor loci. These observations may provide new insights into the molecular basis and variable expressivity of human vWD. 相似文献
107.
Hooper WC; Phillips DJ; Ribeiro MJ; Benson JM; George VG; Ades EW; Evatt BL 《Blood》1994,84(2):483-489
Protein S deficiency, which is associated with thrombosis, can either be inherited or acquired. Recently, we reported that a decrease in free protein S was observed in 19 of 25 persons with HIV/AIDS. The proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), has been reported to be elevated in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients and has been shown to induce a procoagulant state on the surface of endothelial cells. We report here that recombinant TNF-alpha (rTNF-alpha) downregulated protein S synthesis in the SV-40T transfected human microvascular endothelial cell line (HMEC-1) model system by approximately 70% and in primary human umbilical vein and dermal microvascular endothelial cell cultures by approximately 50%. Using the HMEC-1 model, Northern blot analysis showed a decrease in protein S RNA at 24 hours that was corroborated by Western blot analysis and enzyme- linked immunosorbent assay (ELISA) quantification. Evidence supporting the specificity of the TNF-alpha effect included the following: (1) TNF- alpha down-regulation of protein S was completely blocked by TNF neutralizing antibody; (2) the effect was transient, and protein S was restored to near normal levels after TNF was removed from cell cultures; (3) an antibody directed to the TNF RI (55-kD receptor) was shown to mimic the action of TNF-alpha on HMEC-1 cells; and (4) other proinflammatory cytokines, interleukin (IL)-1, IL-6, and TGF-beta, had no effect on protein S secretion. However, TNF-alpha showed no regulatory control over protein S synthesis in the human hepatocellular carcinoma cell line HepG-2. We suggest that TNF-alpha downregulation of protein S may be a mechanism for localized procoagulant activity and thrombosis recently reported in some AIDS patients with associated protein S deficiency. 相似文献
108.
Karen E. Hauer MD Krishan Soni MD Patricia Cornett MD Jeff Kohlwes MD MPH Harry Hollander MD Sumant R. Ranji MD Olle ten Cate PhD Eric Widera MD Brook Calton MD Patricia S. O’Sullivan EdD 《Journal of general internal medicine》2013,28(8):1110-1114
BACKGROUND
Graduate medical education programs assess trainees’ performance to determine readiness for unsupervised practice. Entrustable professional activities (EPAs) are a novel approach for assessing performance of core professional tasks.AIM
To describe a pilot and feasibility evaluation of two EPAs for competency-based assessment in internal medicine (IM) residency.SETTING/PARTICIPANTS
Post-graduate year-1 interns (PGY-1s) and attendings at a large internal medicine (IM) residency program.PROGRAM DESCRIPTION
Two Entrustable professional activities (EPA) assessments (Discharge, Family Meeting) were piloted.PROGRAM FEASIBILITY EVALUATION
Twenty-eight out of 43 (65.1 %) PGY-1 s and 32/43 (74.4 %) attendings completed surveys about the Discharge EPA experience. Most who completed the EPA assessment (10/12, 83.8 %, PGY-1s; 9/11, 83.3 %, attendings) agreed it facilitated useful feedback discussions. For the Family Meeting EPA, 16/26 (61.5 %) PGY-1s completed surveys, and most who participated (9/12 PGY1s, 75 %) reported it improved attention to family meeting education, although only half recommended continuing the EPA assessment.DISCUSSION
From piloting two EPA assessments in a large IM residency, we recognized our reminder systems and time dedicated for completing EPA requirements as inadequate. Collaboration around patient safety and palliative care with relevant clinical services has enhanced implementation and buy-in. We will evaluate how well EPA-based assessment serves the intended purpose of capturing trainees’ trustworthiness to conduct activities unsupervised. 相似文献109.
Background This study aimed to investigate the impact of postoperative complications on long-term survival and disease recurrence in
patients who underwent curative resection for colorectal cancer.
Method Patients who underwent radical resection for colorectal cancer with curative intent from January 1996 to December 2004 were
included. Operative mortality and morbidity were documented prospectively. Factors that might affect long-term outcome were
analyzed with multivariate analysis.
Results Curative resection was performed in 1657 patients (943 men), and the median age was 70 years (range: 24–94 years). The 30-day
mortality was 2.4%, and the complication rate was 27.3%. Age over 70 years (P < .001, odds ratio: 2.06, 95% CI: 1.63–2.61), male gender (P = .001, odds ratio: 1.49, 95% CI: 1.19–1.88), emergency operation (P < .001, odds ratio: 3.14, 95% CI: 2.26–4.35) and rectal cancer (P < .001, odds ratio: 1.41, 95% CI: 1.25–1.61) were associated with a significantly higher complication rate. With exclusion
of patients who died within 30 days, the median follow-up of the surviving patients was 45.3 months. The 5-year overall survival
was 64.9%, and the overall recurrence rate was 29.1%. The presence of postoperative complications was an independent factor
associated with a worse overall survival (P = .023, hazard ratio: 1.26; 95% CI: 1.03–1.52) and a higher overall recurrence rate (P = .04, hazard ratio: 1.26; 95% CI: 1.01–1.57).
Conclusion The presence of postoperative complication not only affects the short-term results of resection of colorectal cancer, but
the long-term oncologic outcomes are also adversely affected. Long-term outcomes can be improved with efforts to reduce postoperative
complications. 相似文献
110.
Y Wang WC Huang CY Wang CC Tsai CL Chen YT Chang JI Kai CF Lin 《British journal of pharmacology》2009,157(6):1004-1013