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51.
Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate 总被引:1,自引:0,他引:1
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A. 相似文献
52.
A statistical analysis of murine stem cell suicide techniques 总被引:1,自引:0,他引:1
The clinical application of soft agar cloning techniques for granulocyte-macrophage stem cells (CFU-C) has resulted in a number of contradictory reports that may in part be due to an inadequate data base. Growth of murine CFU-C is more reproducible and less variable than that of human CFU-C. We utilized in vivo hydroxyurea suicide of murine marrow CFU-C to address the question of how many experiments are needed to detect a specific difference with a p of less than 0.05. In 66 experiments the mean marrow CFU-C hydroxyurea kill was 23.3%; 6-9 separate experiments were necessary to detaect differences of 25%-30%. In order to be sure that a 25%-30% difference is not present, 15-21 experiments were required. Using a Dec-20 computer, 1000 samples of sample size 3, 4, or 10 were drawn from the 66 experiments; it was found that with 3 experiments and a true value of 23%, the actually observed value was below 10%, 17% of the time, and was over 40% in 10% of the samplings. In a smaller number of experiments similar results were obtained analyzing 3HTdR suicide of pluripotent stem cells and CFU- C. These data could provide a base from which to judge the validity of studies utilizing the CFU-C technique. 相似文献
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Cialone J Adams H Augustine EF Marshall FJ Kwon JM Newhouse N Vierhile A Levy E Dure LS Rose KR Ramirez-Montealegre D de Blieck EA Mink JW 《Journal of inherited metabolic disease》2012,35(3):549-555
Juvenile neuronal ceroid lipofuscinosis (JNCL; CLN3 disease; Batten disease) is an autosomal recessive neurodegenerative disease of childhood. Symptoms typically present at school age with vision loss followed by progressive cognitive decline, motor dysfunction, seizures, and behavior problems. Studies on sex differences in JNCL have yielded mixed results, but parent anecdotes suggest that females experience a more precipitous disease course. Therefore, we sought to determine if sex-based differences exist in JNCL. We used data from the Unified Batten Disease Rating Scale (UBDRS), the Batten Disease Support and Research Association (BDSRA) database, and the PedsQL quality of life (QoL) survey to evaluate sex-based differences in functional independence and time from symptom onset to death. On average, females had JNCL symptom onset one year later and death one year earlier than did males. Despite a later age at onset, females had lower functional capability, earlier loss of independent function, and lower physical QoL. Future research in sex differences in JNCL may help to further understand the biological mechanisms underpinning the disease course and may point to targeted therapies. 相似文献
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Hippen KL Bucher C Schirm DK Bearl AM Brender T Mink KA Waggie KS Peffault de Latour R Janin A Curtsinger JM Dillon SR Miller JS Socie G Blazar BR 《Blood》2012,119(2):619-628
In rodent graft-versus-host disease (GVHD) models, anti-IL-21 neutralizing mAb treatment ameliorates lethality and is associated with decreases in Th1 cytokine production and gastrointestinal tract injury. GVHD prevention was dependent on the in vivo generation of donor-inducible regulatory T cells (Tregs). To determine whether the IL-21 pathway might be targeted for GVHD prevention, skin and colon samples obtained from patients with no GVHD or grade 2 to 4 GVHD were analyzed for IL-21 protein expression. By immunohistochemistry staining, IL-21 protein-producing cells were present in all gastrointestinal tract samples and 54% of skin samples obtained from GVHD patients but not GVHD-free controls. In a human xenogeneic GVHD model, human IL-21-secreting cells were present in the colon of GVHD recipients and were associated with elevated serum IL-21 levels. A neutralizing anti-human IL-21 mAb given prophylactically significantly reduced GVHD-associated weight loss and mortality, resulting in a concomitant increase in Tregs and a decrease in T cells secreting IFN-γ or granzyme B. Based on these findings, anti-IL-21 mAb could be considered for GVHD prevention in the clinic. 相似文献
56.
Vincent JJ Odekerken Teus van Laar Michiel J Staal Arne Mosch Carel FE Hoffmann Peter CG Nijssen Guus N Beute Jeroen PP van Vugt Mathieu WPM Lenders M Fiorella Contarino Marieke SJ Mink Lo J Bour Pepijn van den Munckhof Ben A Schmand Rob J de Haan P Richard Schuurman Rob MA de Bie 《Lancet neurology》2013,12(1):37-44
57.
该文旨在对小唾液腺癌的治疗进行回顾。小唾液腺癌可发生在头颈部很多位置,通常表现为黏膜下肿块。影像学检查是对肿瘤发病部位及病变范围内解剖结构的关系进行评估的基础。切取活检或穿吸活检可以决定肿瘤的病理类型和分级。随着分子生物学技术的不断进步,小唾液腺癌的诊断 相似文献
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Rohan PJ Hughes MOptom BVisSc Stephen J Vincent PhD BAppSc Scott A Read PhD BAppSc Michael J Collins PhD MAppSc DipAppSc 《Clinical & experimental optometry》2020,103(1):68-85
Evidence from animal and human studies suggests that ocular growth is influenced by visual experience. Reduced retinal image quality and imposed optical defocus result in predictable changes in axial eye growth. Higher order aberrations are optical imperfections of the eye that alter retinal image quality despite optimal correction of spherical defocus and astigmatism. Since higher order aberrations reduce retinal image quality and produce variations in optical vergence across the entrance pupil of the eye, they may provide optical signals that contribute to the regulation and modulation of eye growth and refractive error development. The magnitude and type of higher order aberrations vary with age, refractive error, and during near work and accommodation. Furthermore, distinctive changes in higher order aberrations occur with various myopia control treatments, including atropine, near addition spectacle lenses, orthokeratology and soft multifocal and dual-focus contact lenses. Several plausible mechanisms have been proposed by which higher order aberrations may influence axial eye growth, the development of refractive error, and the treatment effect of myopia control interventions. Future studies of higher order aberrations, particularly during childhood, accommodation, and treatment with myopia control interventions are required to further our understanding of their potential role in refractive error development and eye growth. 相似文献