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Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.  相似文献   
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INTRODUCTION Crohn’s disease (CD) is a chronic inflammatory disease of the gastrointestinal tract which commonly affects young adults. It follows a relapsing and remitting course and there is no known cure. However, approximately 10% to 15% have chronic …  相似文献   
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目的 初步探讨高迁移率族蛋白B1(HMGB1)致炎效应的信号转导机制。方法 清洁级雄性Wistar大鼠,取其腹腔巨噬细胞,培养3d后以10mg/L HMGB1刺激。刺激完毕后直接在培养瓶中裂解细胞,分别采用免疫沉淀、免疫印迹法和凝胶阻滞分析等技术观察不同时间点Janus激酶2(JAK2)、信号转导及转录激活子—1(STAT1)以及STAT3的活化情况。结果 HMGB1可诱导大鼠腹腔巨噬细胞STAT1、STAT3在短时间内(2h)活化,其中STAT3活化最为迅速,10min即可达到活化高峰。但HMGB1不能在短时间内(2h)诱导JAK2活化。结论 JAK/STAT途径可能参与了HMGB1致炎效应的信号转导机制。  相似文献   
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目的:测量国人全膝关节假体置换术胫骨近端截骨面后缘至腘窝血管之间的距离,以期为临床全膝关节置换术中避免损伤腘窝血管提供参考数据。方法:选择2006-06/12于解放军第二军医大学长征医院体检的50名正常成人(53膝),男29名(31膝),女21名(22膝)。所有观察对象均知情同意,且得到医院伦理道德委员会批准。对所有膝关节进行MRI扫描,在胫骨外侧平台以下10mm水平横断面上辨认腘动静脉,并测量胫骨近端截骨面后缘至腘窝动静脉的距离。结果:53膝全部进入结果分析,无脱落。①男性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.7±2.5,7.3±2.3)mm,95%可信区间分别为5.8~7.6mm,6.5~8.1mm。②女性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.6±1.9,7.1±2.7)mm,95%可信区间分别为:5.8~7.4mm,5.9~8.3mm。③不同性别观察对象胫骨近端截骨面后缘至腘血管的距离差异无显著性意义(P>0.05)。结论:腘窝血管紧邻全膝关节假体置换术胫骨近端截骨面后缘,不同性别间无明显差异。全膝关节假体置换术中进行胫骨近端截骨,特别是后方操作时需特别谨慎,以避免损伤腘窝血管。  相似文献   
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Anophthalmia (no eye), microphthalmia (small eye) and associated ocular developmental anomalies cause significant visual handicap. In most cases the underlying genetic cause is unknown, but mutations in some genes, such as SOX2, cause ocular developmental defects, particularly anophthalmia, in a subset of patients. Here, we describe a four-generation family with a p.Asp123Gly mutation in the highly conserved partner-factor interaction region of the SOX2 protein, which is important for cell-specific actions of SOX2. The proband in this family has bilateral anophthalmia and several other family members have milder ocular phenotypes, including typical optic fissure coloboma. Expression studies indicate that Sox2 is expressed in the eye at the site of closure of the optic fissure during development. The SOX2 mutation in this family implicates the partner-factor interaction region of SOX2 in contributing to the specificity of SOX2 action in optic fissure closure. Our findings indicate that investigation of SOX2 in a broad range of eye anomaly patients aids in the determination of particular functions of SOX2 in development.  相似文献   
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OBJECTIVES: Concerns about unsafe injection practices and possible infections with blood-borne pathogens in the Syrian Arab Republic motivated an assessment of the injection safety situation in the country in July 2001. In light of the recommendations from this assessment, the Ministry of Health of Syria, with the assistance of WHO, implemented a set of activities under the 'Focus Project', which aims to ensure immunization safety. The first phase of the project ran from May 2002 to February 2004, and consisted of the improved provision of injection safety equipment and supplies, the elaboration and wide distribution of national guidelines on injection safety and safe waste management, a behaviour change and communication campaign targeting the general public, and comprehensive training of healthcare workers. A follow-up survey was carried out in February 2004, 2 years after initiation of the project. METHODS: Two representative surveys were conducted using a standardized assessment tool. A cluster sampling strategy, with probability proportionate to the population size, led to the inclusion of 80 health facilities in eight districts in 2001 and of 120 health facilities in 12 districts in 2004. RESULTS: Injection practices had significantly improved 2 years after the start of the project. The 2001 study had pointed to a low, but non-negligible risk to patients (2% unsafe injections), coupled with a high risk to healthcare workers (61% reported needle-stick injuries in the last 12 months) and to the communities owing to unsafe waste disposal (sharps waste found outside 37% of health facilities, waste disposal considered unsafe in 48% of them). The 2004 survey showed that 90% of Syrian healthcare workers had received training in injection safety. All injections observed were given safely (difference to 2001 not significant), although some problems in preparation and reconstitution prevailed. The risk to healthcare workers was significantly reduced as only 14% of the staff reported needle-stick injuries (p < 0.001). The risk to the communities was notably decreased following improvements in sharps waste management (sharps were found in the surroundings of only 13% of health facilities, p < 0.001). CONCLUSIONS: The example of Syria shows that rapid improvement in injection safety is possible and that the necessary tools and methods to monitor and evaluate progress are at our disposal. Challenges remain in transferring this successful programme from the well-structured immunization programme to the more diverse curative health services.  相似文献   
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Currently, little is known about the influence of depressive symptoms and gender-specific aspects in rehabilitation outcome of patients with chronic low back pain. Effects of gender and depressive symptoms on rehabilitation outcome were examined immediately after rehabilitation, as well as three and six months after rehabilitation in 116 patients with chronic low back pain (43 women, 73 men; M=48 yrs.; ICD-10 diagnoses: M45.4/M45.5, M54.4/M54.5). Immediately after rehabilitation, general improvements with medium effect sizes in all rehabilitation measures were found. In contrast, six months after rehabilitation, only pain-related measures showed moderate improvements. Additionally, the mid-term outcomes were influenced by gender and depressive symptoms; women showed more stable rehabilitation outcomes in pain intensity, in the impaired function related to family/leisure, and the coping with pain strategies of "perceived self-competence" and "relaxation". In contrast, especially male patients with severe depressive symptoms revealed regressive rehabilitation outcomes, both in pain-related variables as well as marginally in the coping with pain strategy of "cognitive restructuring". In post-hoc analyses, in the mid-term, they even showed a deterioration of functional capacity and somatisation compared to prior to rehabilitation. Our results suggest that the outcome of orthopaedic rehabilitation may be persistently improved by implementing gender-specific treatments in general and elements of depression treatments for the patients with severe but sub-clinical depressive symptoms.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To develop a fully automated algorithm for accurate detection of fovea location in atrophic age-related macular degeneration...  相似文献   
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