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目的了解河北省儿童医院住院患儿EB病毒(EBV)感染的流行病学特征,为儿童EBV感染的诊断和预防提供科学依据。方法收集2017年1—12月河北省儿童医院0~14岁EBV感染住院患儿的全血样本,采用酶联免疫吸附试验(ELISA)检测其EBV衣壳抗原(VCA)IgG及IgM抗体,抗早期抗原(EA)IgG抗体和抗核抗原1(NA1)IgG抗体,以检测结果为研究样本的抗体谱。根据4种EBV抗体的检测结果分为现症感染(抗VCA-IgM抗体阳性,抗NA1-IgG抗体阴性、抗VCA-IgG抗体、抗EA-IgG抗体阳性或阴性)、亚急性感染(抗VCA-IgG抗体阳性,抗VCA-IgM抗体、抗NA1-IgG抗体、抗EA-IgG抗体阳性或阴性)、既往感染(抗NA1-IgG抗体阳性,抗VCA-IgG抗体阳性或阴性,其他抗体均为阴性)和未感染(4种抗体均阴性)。按照患儿年龄、检出月份和性别分析各组的阳性率。结果共纳入符合要求的样本4 451例,其中3 257例(73.17%)抗体谱提示EBV感染,包括现症感染380例(8.54%)、亚急性感染616例(13.84%)、既往感染2 261例(50.80%)。不同年龄组原发阳性检出率差异有统计学意义(P<0.05),其中学龄前(>3岁)组的阳性检出率最高(P<0.05);不同检出月份组阳性检出率差异有统计学意义(P<0.05),7月份阳性检出率高于其他月份(P<0.05);男性患儿与女性患儿EBV感染率差异无统计学意义(P>0.05)。380例现症感染患儿的疾病谱以血液系统疾病[传染性单核细胞增多症、急性粒细胞缺乏症、血小板减少性紫癜、EBV相关嗜血细胞综合征]为主,其中传染性单核细胞增多症为临床常见疾病;其次是呼吸系统疾病(急性支气管炎、疱疹性咽峡炎、急性扁桃体炎);其他疾病谱包括神经系统疾病及血流感染、肾病综合征、川崎病。结论河北省儿童医院住院患儿EBV阳性检出率有年龄和检出月份差异,现症感染以血液系统疾病患儿为主,医院应根据流学病学特征制定相应预防措施。 相似文献
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Barbara Uhl Katharina T Prochazka Karoline Fechter Katrin Pansy Hildegard T Greinix Peter Neumeister Alexander JA Deutsch 《World journal of gastrointestinal oncology》2022,14(1):153-162
Approximately 8% of all non-Hodgkin lymphomas are extranodal marginal zone B cell lymphomas of mucosa-associated lymphoid tissue (MALT), also known as MALT lymphomas. These arise at a wide range of different extranodal sites, with most cases affecting the stomach, the lung, the ocular adnexa and the thyroid. The small intestine is involved in a lower percentage of cases. Lymphoma growth in the early stages is associated with long-lasting chronic inflammation provoked by bacterial infections (e.g., Helicobacter pylori or Chlamydia psittaci infections) or autoimmune conditions (e.g., Sjögren’s syndrome or Hashimoto thyroiditis). While these inflammatory processes trigger lymphoma cell proliferation and/or survival, they also shape the microenvironment. Thus, activated immune cells are actively recruited to the lymphoma, resulting in either direct lymphoma cell stimulation via surface receptor interactions and/or indirect lymphoma cell stimulation via secretion of soluble factors like cytokines. In addition, chronic inflammatory conditions cause the acquisition of genetic alterations resulting in autonomous lymphoma cell growth. Recently, novel agents targeting the microenvironment have been developed and clinically tested in MALT lymphomas as well as other lymphoid malignancies. In this review, we aim to describe the composition of the microenvironment of MALT lymphoma, the interaction of activated immune cells with lymphoma cells and novel therapeutic approaches in MALT lymphomas using immunomodulatory and/or microenvironment-targeting agents. 相似文献
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Differentiated bronchiolar epithelium in alveolar ducts of rats exposed to ozone for 20 months. 总被引:2,自引:2,他引:2 下载免费PDF全文
K. E. Pinkerton D. E. Dodge J. Cederdahl-Demmler V. J. Wong J. Peake C. J. Haselton P. W. Mellick G. Singh C. G. Plopper 《The American journal of pathology》1993,142(3):947-956
The effects of exposure to 1.0 ppm of ozone for twenty months were studied in male Fischer 344 rats. Light microscopic, morphometric, and immunohistological approaches were used to determine the distribution and degree of differentiation of ciliated and nonciliated bronchiolar epithelial (Clara) cells lining alveolar ducts of the central acinus, a primary target of ozone-induced lung injury. Alveolar duct pathways extending beyond the level of the most proximal alveolar outpocketing of terminal bronchioles were isolated in longitudinal profile. The distance that ciliated and nonciliated bronchiolar epithelial (Clara) cells projected down each alveolar duct pathway was determined by placing concentric arcs radiating outward from a single reference point at the level of the first alveolar outpocketing. A high degree of heterogeneity in the magnitude of bronchiolar epithelial cell extension into alveolar ducts was noted for each isolation and animal. Age-matched control animals also demonstrated variation in the degree of bronchiolar epithelial cell extension down alveolar ducts. In animals exposed to ozone, a striking similarity was noted by scanning electron microscopy in the surface characteristics of cells lining both terminal bronchioles and alveolar ducts. The presence of Clara cell secretory protein in cells of bronchioles and alveolar ducts was also detected immunohistochemically and visualized using confocal laser scanning microscopy in the reflectance mode. Well-differentiated ciliated and nonciliated bronchiolar epithelial cells were found lining alveolar septal tips and alveoli up to a depth of 1,000 mu into the pulmonary acinus after 20 months of exposure to ozone. No evidence of inflammation was present in alveolar ducts, suggesting that epithelial cell transformations in alveolar ducts is a natural consequence of lifetime exposures to oxidant gases. 相似文献
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Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee. 相似文献
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Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar. 下载免费PDF全文
A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. 相似文献