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401.
To further elucidate the natural history of human immunodeficiency virus (HIV) infection, we studied intermediate HIV-related conditions occurring before acquired immunodeficiency syndrome (AIDS) in a prospectively observed multicenter cohort of 738 HIV-infected persons with hemophilia. We analyzed the frequency in adults and children of common HIV-related conditions and the relative risk of AIDS after occurrence of these conditions, controlling for age at seroconversion and the percentage of CD4+ lymphocytes. Thrombocytopenia was the most frequently observed condition with cumulative incidences of 43% +/- 7% in adults and 27% +/- 6% in children and adolescents by 10 years after seroconversion. Oral candidiasis, fever, weight loss, and non-AIDS pneumonia were two to four times more common in adults than children, whereas herpes zoster risk was similar in the two age groups. HIV- related conditions were infrequent during the first 4 years of infection, particularly in children. With the exception of thrombocytopenia, mean CD4 counts were less than 350 cells/microL at the onset of the conditions. The relative hazard of AIDS after oral candidiasis was 18 in children and 3.8 in adults. Relative hazard in adults was also increased after persistent fever (10), weight loss (3.2), and non-AIDS pneumonia (2.2). Herpes zoster and thrombocytopenia were not significantly associated with AIDS in either age group. We conclude that intermediate HIV-related conditions occur more frequently in adults than in children with hemophilia. Persistent fever is the strongest predictor of AIDS in adults, whereas oral candidiasis is the strongest predictor in children. These findings should facilitate the design and conduct of clinical trials as well as the management of HIV- infected children and adults.  相似文献   
402.
We studied the effects of cis-retinoic acid (cisRA) on the clonogenic growth of samples of leukemic cells from 35 patients with acute nonlymphocytic leukemia (ANLL). We observed significant inhibition of leukemic colony growth in 17 samples by 10(-7) to 10(-6)M cisRA. However, we found that retinoid exposure resulted in striking stimulation of clonal growth in ten samples at the same drug concentrations. With the exception of cases with promyelocytic features, there was no morphologic or functional evidence that cisRA induced the leukemic blasts to differentiate. Both inhibition and stimulation were dose-dependent and observable at pharmacologically achievable levels of cisRA. Leukemic cells with monocytic features more frequently demonstrated a stimulatory response than did those without monocytic features. Depletion of T lymphocytes and monocytes did not alter the type of growth response. Assays for cellular retinoic acid- binding protein (CRABP) were performed on five samples (two with inhibitory growth responses, two with stimulatory responses, and one with no growth) and failed to reveal detectable levels of CRABP in any case. The addition of cisRA to liquid suspensions of leukemic cells produced no significant change in the number of viable cells. We conclude that the effects of cisRA on leukemic colony growth are not cytotoxic and not mediated by T lymphocytes, monocytes, or CRABP. More importantly, cisRA appears to enhance the growth of certain human leukemia cells in vitro. Taking into account the increasing use of retinoids in clinical trials for patients with leukemia, the latter findings may represent a significant cautionary note.  相似文献   
403.

Background  

Clinical spectrum, microbiology and outcome of empyema thoracis are changing. Intrapleural instillation of fibrinolytic agents is being increasingly used for management of empyema thoracis. The present study was carried out to describe the clinical profile and outcome of patients with empyema thoracis including those with chronic empyema and to study the efficacy and safety of intrapleural streptokinase in its management.  相似文献   
404.
Segal  GM; McCall  E; Bagby  GC Jr 《Blood》1988,72(4):1364-1367
Interleukin-1 (IL-1) induces cultured human umbilical vein endothelial cells to elaborate heterogeneous hematopoietic growth factors, including granulocyte-macrophage and granulocyte colony-stimulating factors (GM-CSF and G-CSF, respectively). Because erythroid burst- promoting activity (BPA) is also elaborated by endothelial cells exposed to IL-1, we sought to determine whether the BPA released by IL- 1-induced endothelial cells simply reflects the known erythropoietic activity of GM-CSF or whether other uncharacterized factors might be involved. Media conditioned by multiply passaged endothelial cells cultured for three days with recombinant IL-1 alpha (ECMIL-1) stimulated erythroid burst and GM colony formation in cultures of human nonadherent T-lymphocyte-depleted marrow mononuclear cells. Pretreatment with an anti-GM-CSF antiserum neutralized all the BPA and 56% of the GM colony-stimulating activity (GM-CSA) in ECMIL-1. The antiserum used in these studies did not inhibit IL-3 or G-CSF activity and did not inhibit ECMIL-1-induced murine GM colony growth (a measure of human G-CSF). To examine whether GM-CSF induces BPA release by accessory cells, media conditioned by marrow cells cultured for three days with GM-CSF were tested in the colony growth assays. Pretreatment with anti-GM-CSF antiserum completely neutralized the BPA and GM-CSA of the marrow cell-conditioned medium. We conclude that GM-CSF is the BPA elaborated by IL-1-induced endothelial cells. The in vitro erythropoietic activity of GM-CSF is not dependent on induced BPA release by accessory cells and therefore likely results from a direct effect of GM-CSF on progenitor cells.  相似文献   
405.
406.
Baldwin  GC; Benveniste  EN; Chung  GY; Gasson  JC; Golde  DW 《Blood》1993,82(11):3279-3282
We previously showed the presence of receptors for granulocyte- macrophage colony-stimulating factor (GM-CSF) on tumor tissues and tumor cell lines that are derived from the neural crest. To determine whether normal neural cells express functional GM-CSF receptors, we isolated and analyzed primary rat brain cells, including microglia, astrocytes, and oligodendrocytes. Scatchard analysis of equilibrium binding of 125I-GM-CSF to primary rat oligodendrocytes showed an average of 1,110 GM-CSF binding sites per cell, with a kd of 20 pmol/L. In six separate experiments, no specific binding was detectable on the astrocyte population. Microglia were used in competitive binding experiments with oligodendrocytes, and addition of microglia did not increase the specific binding of labeled ligand to oligodendrocytes. In dose-response assays, we measured 3H-thymidine uptake in rat oligodendrocytes, microglia and control murine 32D cells stimulated with various concentrations of GM-CSF. Over concentration ranges of 0.025 to 1000 pmol/L, cell proliferation and peak 3H-thymidine incorporation was observed at approximately 30 pmol/L for both the control cells and the oligodendrocytes. However, the microglial cells did not proliferate in response to GM-CSF. These data indicate the presence of a functional receptor for GM-CSF on primary rat oligodendrocytes, and suggest that hematopoietic growth factors such as GM-CSF may play a role in nerve cell development, function, or response to injury.  相似文献   
407.
目的:脐血处理的关键问题是提高干细胞的回收率及实现处理过程的标准化和可重复化,实验对此进行探讨,比较干细胞分离仪与传统羟乙基淀粉手工法分离脐血的效果。方法:实验于2006-12/2007-05在广州医学院附属市一人民医院完成。①脐血来源:39份脐血采自广州医学院附属市一人命医院妇产科健康顺产新生儿脐带,产妇均知情同意。随机数字表法分为仪器分离组17份、手工分离组22份。②实验方法:仪器分离组收集脐血称质量,计算体积,在开始处理前20min缓慢加入相当于20%脐血体积的60g/L羟乙基淀粉。仪器分离组按仪器要求自动分离,分离终体积20mL。手工分离组50g离心5min,压浆板压出全部血浆以及18mL红细胞移至无菌空袋,500g离心13min,自动压浆板压出血浆,保留20mL终体积样本。③实验评估:采用全自动计数仪进行检测有核细胞(白细胞)、红细胞数量。流式细胞仪分析CD34 含量。结果:采用干细胞分离仪处理浓缩脐血,有核细胞回收率为(89.7±3.4)%,CD34 细胞回收率为(98.8±5.1)%,红细胞去除率为(55.2±16.7)%,均比手工分离组分离效果好,差异有显著性意义(P<0.05或0.01)。同时,仪器分离组有核细胞回收率、CD34 细胞回收率的标准差均明显低于手工分离组(3.4vs.15.3;5.1vs.10.3)。结论:相比传统的羟乙基淀粉手工分离法,干细胞分离仪脐血分离浓缩效果理想,且结果标准误小,数据稳定。  相似文献   
408.

Aims

Sex differences in long-term outcomes following hospitalization for heart failure (HF) across ejection fraction (EF) subtypes are not well described. In this study, we evaluated the risk of mortality and rehospitalization among males and females across the spectrum of EF over 5 years of follow-up following an index HF hospitalization event.

Methods and results

Patients hospitalized with HF between 1 January 2006 and 31 December 2014 from the American Heart Association's Get With The Guidelines-Heart Failure registry with available 5-year follow-up using Medicare Part A claims data were included. The association between sex and risk of mortality and readmission over a 5-year follow-up period for each HF subtype (HF with reduced EF [HFrEF, EF ≤40%], HF with mildly reduced EF [HFmrEF, EF 41–49%], and HF with preserved EF [HFpEF, EF >50%]) was assessed using adjusted Cox models. The effect modification by the HF subtype for the association between sex and outcomes was assessed by including multiplicative interaction terms in the models. A total of 155 670 patients (median age: 81 years, 53.4% female) were included. Over 5-year follow-up, males and females had comparably poor survival post-discharge; however, females (vs. males) had greater years of survival lost to HF compared with the median age- and sex-matched US population (HFpEF: 17.0 vs. 14.6 years; HFrEF: 17.3 vs. 15.1 years; HFmrEF: 17.7 vs. 14.6 years for age group 65-69 years). In adjusted analysis, females (vs. males) had a lower risk of 5-year mortality (adjusted hazard ratio [aHR] 0.89, 95% confidence interval [CI] 0.87–0.90, p < 0.0001), and the risk difference was most pronounced among patients with HFrEF (aHR 0.87, 95% CI 0.85–0.89; pinteraction[sex*HF subtype] = 0.04). Females (vs. males) had a higher adjusted risk of HF readmission over 5-year follow-up (aHR 1.06, 95% CI 1.04–1.08, p < 0.0001), with the risk difference most pronounced among patients with HFpEF (aHR 1.11, 95% CI 1.07–1.14; pinteraction[sex*HF subtype] = 0.001).

Conclusions

While females (vs. males) had lower adjusted mortality, females experienced a significantly greater loss in survival time than the median age- and sex-matched US population and had a greater risk of rehospitalization over 5 years following HF hospitalization.  相似文献   
409.
Since May 2022, an international monkeypox (MPX) outbreak has been ongoing in more than 50 countries. While most cases are men who have sex with men, transmission is not restricted to this population. In this report, we describe the case of a male child younger than 10 years with MPX in the Netherlands. Despite thorough source tracing, a likely source of infection has not been identified. No secondary cases were identified in close contacts.  相似文献   
410.
Astroblastoma is a rare central nervous system tumor. We reported a case of a 24‐year‐old Nepalese woman with radiological features mimicking pilocytic astrocytoma which came out to be low‐grade astroblastoma in histopathological and immunohistochemistry examination after total excision of the tumor.  相似文献   
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