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81.
This randomized phase III clinical trial explored the efficacy of DaunoXome (DNX) versus Daunorubicin (DNR) in acute myeloid leukaemia (AML) patients aged >60 years. Three hundred and one AML patients were randomized to receive DNR (45 mg/m(2) days 1-3) or DNX (80 mg/m(2) days 1-3) plus cytarabine (AraC; 100 mg/m(2) days 1-7). Patients in complete remission (CR) received a course of the same drugs as consolidation and then were randomized for maintenance with AraC+ all trans retinoic acid or no further treatment. Among 153 patients in the DNR arm, 78 (51.0%) achieved CR, 55 (35.9%) were resistant and 20 (13.1%) died during induction. Among 148 patients in the DNX arm, 73 (49.3%) achieved CR, 47 (31.8%) were resistant and 28 (18.9%) died during induction. Univariate analysis showed no difference as to induction results. After CR, DNX showed a higher incidence of early deaths (12.5% vs. 2.6% at 6 months, P = 0.053) but a lower incidence of relapse beyond 6 months (59% vs. 78% at 24 months, P = 0.064), with a cross in overall survival (OS) and disease-free survival (DFS) curves and a later advantage for DNX arm after 12 months from diagnosis. DNX seems to improve OS and DFS in the long-term follow-up, because of a reduction in late relapses.  相似文献   
82.
We report on a case of metastatic adenocarcinoma of liver that was removed and examined histochemically after microwave coagulation therapy (MCT). The patient was a 65-year-old woman who had a metastatic tumor in the liver (S3) after high anterior resection due to a rectal adenocarcinoma and received MCT against the tumor. One month after MCT, multiple metastatic tumors were detected by abdominal computed tomography (CT) scan. As it was difficult to control them by MCT alone, we performed lateral segmentectomy. To assess the effects of microwave ablation on cellular viability of metastatic tumor, we used enzyme histochemistry for acid phosphatase (AcP), which is positive in macrophages infiltrating in the tumor. In a part of the ablated area of resected liver, there was remaining neoplastic tissue of which the morphology was maintained in H&E staining. This was found to be microwave-fixed non-viable tissue because no enzyme activity of AcP was detected in the infiltrating macrophages. This case report suggests that enzyme histochemistry was useful to assess the effect of MCT, enabling us to distinguish fixed cells from viable cells.  相似文献   
83.
84.
The present study investigated the contractile reserve of myocardium exhibiting reverse redistribution (RRD) of thallium-201 (201Tl) after acute myocardial infarction. Forty patients experiencing their first acute myocardial infarction underwent resting 201Tl single-photon emission computed tomography (SPECT) and low-dose (5-10 microgxkg(-1)xmin(-1)) dobutamine stress echocardiography (DSE) within 4 weeks after the onset of infarction. The left ventricle was divided into 13 segments for analysis. The severity of defects in 201Tl SPECT and the extent of wall motion abnormality in DSE were visually assessed and scored. The sum of each defect score and wall motion score of infarct-related segments were defined as total defect score (TDS) and total wall motion score (TWM), respectively. Quantitative analysis of 201Tl uptake was also performed. Resting 201Tl SPECT revealed RRD in 16 patients (group RRD), fixed defect (FIX) in 23 patients (group FIX), and redistribution in one. There was a significant difference in improvement of TWM between rest and stress in TWM in both the RRD and FIX groups (p<0.0001, each case). The improvement of TWM with dobutamine was significantly greater in RRD than in FIX (1.6+/-1.0 vs 0.6+/-0.7, p=0.001). There was a positive correlation between the magnitude of RRD and improvement of TWM with dobutamine (r=0.48, p=0.002). Myocardium exhibiting RRD on 201Tl SPECT in patients with acute myocardial infarction has greater contractile reserve than that exhibiting a fixed defect.  相似文献   
85.
86.
The aim of this article is to provide an inventory of the use of contrast‐enhanced ultrasound (CEUS) in relation to percutaneous interventional procedures. The article is structured into a systematic literature review followed by a clinical part relating to percutaneous CEUS‐guided procedures. A literature search identified 3109 records. After abstract screening, 55 articles were analyzed and supplemented with pictorial material to explain the techniques. In conclusion, the best‐evidenced indications for CEUS‐guided interventions are biopsy and ablation of inconspicuous or B‐mode–invisible tumors, intraprocedural ablation control and follow‐up, as well as percutaneous transhepatic cholangiography and drainage procedures.  相似文献   
87.
BACKGROUNDOral tacrolimus is a therapeutic agent for moderate to severe steroid-dependent or resistant ulcerative colitis (UC), but remission induction is difficult, and it is necessary to treat the patient while considering the next treatment.AIMTo examine serum albumin (Alb) level as a prognostic factor for the therapeutic effect of tacrolimus in clinical practice.METHODSForty-seven patients with UC treated with tacrolimus at our institution were divided into remission and failure groups (colectomy or switch to biologics), and the biological data at the start of observation and at weeks 1 and 2 were retrospectively examined. Kaplan-Meier and multivariate analyses were performed using Alb as a prognostic factor in UC treatment.RESULTSDuring the three months observed, 17 (36.2%) patients failed treatment with tacrolimus. A comparison between the failure and remission groups showed a significant difference only in Alb in week 2, and in the week 2/week 0 Alb ratio, which showed the rate of change in Alb. The cut-off value of the week 2/week 0 Alb ratio that predicted failure was 1, and its area under the curve was 0.751 (95%CI: 0.604-0.898). In the Kaplan-Meier analysis, a week 2/week 0 Alb ratio ≤ 1 had a significantly higher failure rate than that of > 1; Cox proportional hazard regression analysis also showed that a week 2/week 0 Alb ratio ≤ 1 was an independent prognostic factor for failure within 3 mo after the start of tacrolimus treatment.CONCLUSIONA week 2/week 0 Alb ratio ≤ 1 predicts failure within 3 mo of tacrolimus administration for UC. High failure risk exists with week 2 Alb values ≤ 1 on admission.  相似文献   
88.
CD13/aminopeptidase N (E.C.3.4.11.2) is an ectoenzyme located in the outer membrane of a variety of cells. Because aminopeptidase expression was shown to be upregulated by a Th1-related cytokine, IFN-gamma, we examined here the significance of CD13/aminopeptidase N in pulmonary sarcoidosis. The activity of aminopeptidase in bronchoalveolar lavage fluid (BALF) was significantly higher in patients with sarcoidosis than in normal volunteers (NV) and control patients (CP). The activity significantly correlated with lymphocyte percentages and the ratio of CD4+ to CD8+ T lymphocytes in the BALF, and was higher in patients with sarcoidosis with parenchymal involvement than in those without the involvement. CD13/aminopeptidase N protein, which has a molecular mass of approximately 150 kD, was detectable in alveolar macrophages (AM) from patients with sarcoidosis at higher levels than in those from NV. CD13/aminopeptidase N induced in vitro chemotactic migration of human lymphocytes in a concentration range of 10(-)(5) to 10(-)(1) U/ml. The chemotactic activity was greater for CD4+ T lymphocytes than for CD8+ T lymphocytes. The enzymatic activity of CD13/aminopeptidase N was responsible for the chemotactic activity because bestatin, an inhibitor of CD13/aminopeptidase N, abolished the chemotactic activity. Higher chemotactic activity for lymphocytes was detected in the BALF from patients with sarcoidosis than in that from NV, and the activity was significantly decreased by treatment with bestatin. This study indicates that CD13/ aminopeptidase N expressed in AM may have a role in T-lymphocyte involvement in the sarcoid lung and the pathogenesis of alveolitis in this disorder.  相似文献   
89.
F E Millard  P Tani  R McMillan 《Blood》1987,70(5):1495-1499
Alloimmunization to donor class I HLA antigens represents a major obstacle to successful platelet transfusion therapy. It is desirable to distinguish alloimmunization from nonimmunologic causes of poor platelet survival to assess the need for HLA-matched, single-donor platelets. We describe a new in vitro assay for anti-HLA antibodies and report its application to the problem of platelet crossmatching. In contrast to previously described crossmatch techniques, the immunobead assay is specific for anti-HLA antibodies. The assay was used to evaluate 51 single-donor platelet transfusions given to seven patients from 35 different donors. Recipient plasma was assayed for antibodies directed against HLA antigens present on donor platelets. A one-hour posttransfusion corrected count increment of greater than or equal to 7,500 was considered a successful outcome. Twenty-nine of 33 (87.9%) transfusion episodes associated with a negative immunobead assay had successful outcomes. The four unsuccessful transfusions were associated with potential nonimmunologic causes of poor platelet survival. Only two of 18 (11.1%) episodes associated with a positive assay had successful outcomes. Only one unsuccessful transfusion episode was associated with a negative immunobead assay and a positive radiolabeled antiglobulin test result, which suggested that isolated alloantibodies to antigens other than class I HLA antigens are not a common cause of platelet refractoriness. Platelets stored in suspension at 4 degrees C or frozen in liquid nitrogen were found suitable for crossmatch testing.  相似文献   
90.
Enrichment for murine keratinocyte stem cells based on cell surface phenotype   总被引:54,自引:0,他引:54  
The identification and physical isolation of epithelial stem cells is critical to our understanding of their growth regulation during homeostasis, wound healing, and carcinogenesis. These stem cells remain poorly characterized because of the absence of specific molecular markers that permit us to distinguish them from their progeny, the transit amplifying (TA) cells, which have a more restricted proliferative potential. Cell kinetic analyses have permitted the identification of murine keratinocyte stem cells (KSCs) as slowly cycling cells that retain [(3)H]thymidine ([(3)H]Tdr) label, termed label-retaining cells (LRCs), whereas TA cells are visualized as rapidly cycling cells after a single pulse of [(3)H]Tdr, termed pulse-labeled cells (PLCs). Here, we report on the successful separation of KSCs from TA cells through the combined use of in vivo cell kinetic analysis and fluorescence-activated cell sorting. Specifically, we demonstrate that murine dorsal keratinocytes characterized by their high levels of alpha(6) integrin and low to undetectable expression of the transferrin receptor (CD71) termed alpha(6)(bri)CD71(dim) cells, are enriched for epithelial stem cells because they represent a minor ( approximately 8%) and quiescent subpopulation of small blast-like cells, with a high nuclear:cytoplasmic ratio, containing approximately 70% of label-retaining cells, the latter being a well documented characteristic of stem cells. Conversely, TA cells could be enriched in a phenotypically distinct subpopulation termed alpha(6)(bri)CD71(bri), representing the majority ( approximately 60%) of basal keratinocytes that are actively cycling, and importantly contain approximately 70% of [(3)H]Tdr pulse-labeled cells. Importantly, immunostaining of dorsal skin revealed the presence of CD71(dim) cells in the hair follicle bulge region, a well documented location for KSCs.  相似文献   
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