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81.
We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken.  相似文献   
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The purpose of these studies was to determine the molecular basis of the phenotypic mosaicism that is a defining feature of paroxysmal nocturnal hemoglobinuria (PNH). Analysis of T cell clones from a female patient revealed four distinct phenotypes based on surface expression of glycosyl phosphatidylinositol-anchored proteins (GPI-AP). When PIG-A (the gene that is mutant in PNH) from these clones was analyzed, four discrete somatic mutations were identified. Analysis of X chromosomal inactivation among the abnormal T cell clones was consistent with polyclonality. Together, these studies demonstrate that the phenotypic mosaicism that is characteristic of PNH is a consequence of genotypic mosaicism and that, at least in this case, PNH is a polyclonal rather than a monoclonal disease. That four distinct somatic mutations were present in a single patient suggests that in conditions that predispose to PNH PIG-A may be hypermutable.  相似文献   
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Daniels  TM; Fass  DN; White  JG; Bowie  EJ 《Blood》1986,67(4):1043-1047
We report a new bleeding disease--storage pool deficiency (SPD) of platelets--in pigs from the Mayo swine colony of homozygous von Willebrand's disease (vWD) and of heterozygous carriers of vWD. Levels of factor VIII, von Willebrand factor antigen (vWF:Ag), and ristocetin cofactor (RCof) were similar in the vWD carriers and SPD pigs. The latter pigs, however, had bleeding times of 15 minutes or more and were severe bleeders, in contrast to clinically normal vWD carriers. Platelet aggregation in response to collagen was reduced in most SPD pigs. Total platelet content of ADP, ATP, and serotonin was less than that of normal pigs. While the initial uptake of 14C-labeled serotonin into platelets was similar in SPD and normal pigs, retention of serotonin was reduced in platelets of SPD pigs. Transmission electron microscopy showed a large decrease of dense bodies in the platelets of SPD pigs. These findings support a diagnosis of SPD. Genetic analyses suggest an autosomal recessive mode of inheritance. A breeding program is under way to produce pigs affected only at the SPD gene, thus allowing further characterization of SPD and SPD-carrier pigs.  相似文献   
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Background  

Improved survival due to advances in neonatal care has brought issues such as postnatal growth and development more to the focus of our attention. Most studies report stunting in children born very preterm and/or small for gestational age. In this article we study the growth pattern of these children and aim to identify factors associated with postnatal catch-up growth.  相似文献   
89.

Background

Late or inadequate therapeutic management increases the risk of mortality associated with HIV/AIDS. The aim of this study was to analyze the proportion and factors associated with loss of follow-up in HIV patients who receiving antiretroviral therapy at Conakry.

Methods

A retrospective cohort study was conducted in HIV patients aged over 15 years and who receiving antiretroviral therapy. Between August 1, 2008 and July 31, 2015, all patients managed by the ambulatory treatment center of the Guinean Women Association against AIDS and sexually and transmissible infection were included. Loss of follow-up was defined as no follow-up visit within 3 months. Kaplan–Meier curves and multivariate Cox regression models were used to analyze factors associated with loss of follow-up. Analyses were performed by using Stata 13 software.

Results

614 patients aged 36.3 ± 11.2 years, mainly females (68.4%) and living in Conakry (80.5%) were included. Among them, 104 were loss to follow-up, corresponding to a proportion rate of 16.9% (95% CI: 14.2–19.7%) or 5.79/100 person-years. The results of multivariate analyses showed that factors independently associated with loss of follow-up were malnutrition (AHR = 7.05; 95% CI: 2.05–24.27; P = 0.002) and CD4 cells account at the initiation of AHR (2.35; 95% CI: 1.61–6.39; P = 0.016) in patients with 201–350 CD4/μL and 5.83 (95% CI: 2.85–11.90; P < 0.001) in patients with less than 150 CD4/μL.

Conclusion

Despite efforts of health care workers and free antiretroviral therapy, many patients were loss to follow-up. Multivariate analysis showed that malnutrition and low CD4 account were independently associated with loss to follow-up.  相似文献   
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