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101.
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IgG antibodies against pneumococcal polysaccharides are found predominantly within IgG subclass 2. We wished to evaluate retrospectively IgG subclasses and post-immunization pneumococcal antibody titers in children with recurrent respiratory infections. We examined total immunoglobulin levels and IgG subclasses, as well as pneumococcal antibody titers against serotypes 3, 7F, 9N, and 14 present 4–6 weeks after pneumococcal immunization in 56 children 2–18 years old. Titers >200 ng Ab N/ml to any of the 4 serotypes tested were arbitrarily considered protective. Four patients did not have protective antibody levels against any of the 4 serotypes tested following vaccination. Of those, 3 had normal IgG subclass levels and 1 had an IgG2 subclass deficiency. Of 3 additional patients with IgG2 deficiency, 2 had protective antibody levels to only 1 serotype and 1 had protective antibody levels to 2 serotypes. Furthermore, in 2 patients with undetectable IgG2 at the time of immunization, the response was only transient. We conclude that patients with IgG2 deficiency may not develop protective antibody levels to all pneumococcal serotypes and that some may have deficient memory for IgG anti-pneumococcal polysaccharide antibodies. Pediatr Pulmonol. 1996; 22:167–173. © 1996 Wiley-Liss, Inc.  相似文献   
103.
Background and purpose: Neuromyelitis optica (NMO) or Devic′s disease is a rare inflammatory and demyelinating autoimmune disorder of the central nervous system (CNS) characterized by recurrent attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM), which is distinct from multiple sclerosis (MS). The guidelines are designed to provide guidance for best clinical practice based on the current state of clinical and scientific knowledge. Search strategy: Evidence for this guideline was collected by searches for original articles, case reports and meta‐analyses in the MEDLINE and Cochrane databases. In addition, clinical practice guidelines of professional neurological and rheumatological organizations were studied. Results: Different diagnostic criteria for NMO diagnosis [Wingerchuk et al. Revised NMO criteria, 2006 and Miller et al. National Multiple Sclerosis Society (NMSS) task force criteria, 2008] and features potentially indicative of NMO facilitate the diagnosis. In addition, guidance for the work‐up and diagnosis of spatially limited NMO spectrum disorders is provided by the task force. Due to lack of studies fulfilling requirement for the highest levels of evidence, the task force suggests concepts for treatment of acute exacerbations and attack prevention based on expert opinion. Conclusions: Studies on diagnosis and management of NMO fulfilling requirements for the highest levels of evidence (class I–III rating) are limited, and diagnostic and therapeutic concepts based on expert opinion and consensus of the task force members were assembled for this guideline.  相似文献   
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目的:观察人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中初步构建组织工程软骨的可行性。方法:实验于2005-04/2006-05在解放军总医院骨科研究所完成。脂肪组织和关节软骨均来自膝关节置换术中切除的组织,并经患者知情同意。关节软骨冻干后经粉碎机粉碎,过筛,选取25~38μm大小的软骨微粒。在样品中先加入2.5g/L胰蛋白酶,37℃消化24h,再加入1%Triton X-100震荡72h。将软骨微粒和蒸馏水按1∶3的比例混合后滴加在模板中,置入冷冻干燥机冻干后行紫外线交联。紫外线照射8h完成。最后经25kGy 60Co辐照灭菌完成支架制备。取膝关节置换术中切除的髌下脂肪垫,酶消法获得脂肪干细胞,扩增后复合于脱细胞软骨基质制成圆柱状三维支架上(细胞密度5×1010L-1),置于生物反应器中进行诱导培养,同时设静态培养组作为对照,3周后观测大体形态和组织学形态变化,同时进行组织化学(包括番红花O,阿利新蓝染色)和Ⅱ型胶原免疫组织化学分析。结果:生物反应器组诱导培养3周苏木精-伊红染色显示支架结构消失,只有中心区域残存少量支架结构;静态培养组支架结构尚存在,有少量基质分泌。番红花O染色显示生物反应器组细胞外有大量蛋白聚糖沉积,阿利新蓝染色表明有软骨特异性蛋白多糖的聚集;而静态培养组只有部分区域染色且淡于生物反应器组。Ⅰ型胶原免疫组化的结果显示,在生物反应器组细胞能够合成大量软骨细胞特异性胶原成分,而静态培养组呈弱阳性。结论:生物反应器培养明显促进了脂肪干细胞的增殖与软骨分化,是体外构建组织工程软骨的良好方法。  相似文献   
106.
Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
107.
目的:探索可早期预测严重败血症病人死亡的临床和实验室指标或系统模型。方法:对ICU连续收治的26例严重败血症病人行前瞻性观察28天,分析其死亡的相关临床和实验室指标。结果:共有14人(54%)死亡,多死于第1周内(74%)。根据循环中的细胞间粘附分子-1水平能早期预测其脏器衰竭和死亡。一些临床指标水平在死亡病人与生存病人之间差别较大,其中包括血总胆红素、pH值、红细胞压积、氧合指数、动静脉血氧差、四项SIRS指标和一些血流动力学指标等。结论:综合上述指标可以尝试建立起了一个能够早期评估病人死亡可能性的积分系统。  相似文献   
108.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析.  相似文献   
109.
Nintedanib (BIBF 1120) is a small, orally available, triple angiokinase inhibitor in phase III development (various indications) that targets VEGFR 1–3, FGFR 1–3, and PDGFR-α/β. This open-label, uncontrolled, phase II study assessed the efficacy and safety of nintedanib in patients with recurrent glioblastoma multiforme (GBM) who had previously failed radiotherapy plus temozolomide as first-line therapy (STUPP), or the same regimen with subsequent bevacizumab-based therapy as second-line treatment (BEV). Patients with a performance status of 0–1, histologically proven GBM, and measurable disease (by RANO) were enrolled. Nintedanib was given orally at a dose of 200 mg twice daily (bid), with magnetic resonance imaging undertaken every 8 weeks. The primary endpoint was objective response rate. The study was stopped prematurely following a preplanned futility analysis after inclusion of 13 patients in the STUPP arm and 12 in the BEV arm. Best response was stable disease (SD) in three patients (12 %); all other patients progressed within the first four 28-day cycles. One patient in the BEV arm has had SD for 17+ months. Median progression-free survival was 1 month and median overall survival was 6 months. Nintedanib had an acceptable safety profile, with no CTCAE grade 3–4 adverse events. Common adverse events were CTCAE grade 1–2 fatigue, loss of appetite, diarrhea, and nausea. Single-agent nintedanib (200 mg bid) demonstrated limited, but clinically non-relevant antitumor activity in patients with recurrent GBM who had failed 1–2 prior lines of therapy.  相似文献   
110.
Objective: Power take-off (PTO) driveline entanglements are a primary source of injury on US farms. As with many farm injury concerns, hazard control technology is widely available for mitigating the risk of these entanglements. Despite the availability of hazard control technology, PTO shields are damaged or missing on approximately 57% of PTO driveline implements in New York. Given the catastrophic nature of entanglements and the ready access to safety technology, a better understanding of what motivates farmers to install or replace PTO shields is warranted. Methods: To examine this question, agricultural health and safety researchers in New York State conducted an initial comparison of PTO shield sales on farms receiving one of three different interventional approaches. These included PTO shield audits, a social marketing campaign, and on-farm safety services. PTO shield purchases were tracked from January 2011 through June 2016 on farms receiving these interventions and on other farms that were not exposed to interventional strategies. Results: Results indicate that a significantly higher number of PTO shields were purchased on farms that requested and received on-farm safety services versus farms that were exposed to PTO shield audits, the social marketing campaign, or the control group. PTO shield sales were slightly elevated on farms receiving driveline audits, as compared with control farms (although these differences were not significant). Conclusions: No marked differences in sales were noted between control farms and farms exposed to the social marketing campaign. Only one of the three interventional strategies (on-farm safety services) approached the number of PTO shield sales necessary to prevent an entanglement.  相似文献   
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