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51.
Several limitations of the use of embryonated eggs and the threat of pandemics have highlighted the need for other platforms for the production of influenza vaccines. We report the indigenous development and pre-clinical testing of an MDCK-based H1N1 pandemic influenza vaccine HNVAC from India. The cell bank and virus seed were characterized extensively. The cells were characterized by PCR, electron microscopy, and karyotyping, and found to be of female canine epithelial origin. The virus was confirmed by neutralization, haemagglutination inhibition, neuraminidase inhibition, and PCR and nucleotide sequencing. Adventitious agent testing was performed by both in vitro and in vivo studies. The in vitro studies included culturing, haemadsorption, haemagglutination, PCR and RT-PCR, whereas in vivo studies included passage in embryonated eggs and in laboratory animals. Both cell bank and virus seed were free of adventitious agents. MDCK cell lysates as well as cellular DNA did not produce tumours in newborn or adult laboratory animals. The bioprocess parameters were standardized to recover antigen with minimal levels of process-related impurities. The vaccine bulk was tested for the presence of specific antigen, and quantified by single radial immunodiffusion. Finally, non-adjuvanted and aluminium hydroxide adjuvanted vaccine formulations were found to be safe in preclinical toxicity studies in mice, rats, guinea pigs and rabbits, and immunogenic in mice and rabbits. This is the first and only cell culture-based influenza vaccine platform developed in any developing country.  相似文献   
52.
The aim of this study is to assess the efficacy of microwave irradiation in disinfecting gypsum casts and also to compare its efficacy with validated method of chemical disinfection. The present study is an ex vivo study conducted on a sample of five irreversible hydrocolloid impressions in vitro and on ten patients gypsum casts in vivo following standard impression techniques to check the efficacy of microwave oven irradiation and compare its efficacy with standard chemical method of disinfection. Results were analysed using Mann–Whitney test and Wilcoxon signed rank test. Untreated gypsum casts showed cfu/ml counts with a median log value of 6, while microwave-irradiated ones had median cfu/ml counts of 0. Casts poured from chemically disinfected impressions demonstrated cfu/ml counts with a median log value of 5. Microwave irradiation was found to be effective in disinfecting gypsum casts when compared to chemical disinfectant in disinfecting dental impressions.  相似文献   
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The loss of maxillary central incisors at an early age has psychological, esthetic, and functional implications. Multiple treatment options are available for replacing missing central incisors. The management demands a multidisciplinary approach involving the orthodontist, prosthodontist, and periodontist. Treatment planning requires consideration of a variety of clinical and nonclinical factors. This clinical report attempts to demonstrate different strategies for the management of unilaterally and bilaterally missing central incisors.  相似文献   
55.
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   
56.
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted.  相似文献   
57.
Atherosclerotic renal artery stenosis (ARAS) is an important cause of kidney disease, accelerated hypertension (HTN), and its treatment is controversial. Our aim was to evaluate the outcomes, safety, and efficacy of percutaneous transluminal angioplasty (PTA) for ARAS. Retrospective analysis of ARAS was performed among 470 angiographies during 1995–2010. Patients with nonatherosclerotic RAS and renal transplant were excluded. We assessed preintervention and postintervention mean arterial pressure (MAP), antihypertensive medications, and renal function to classify as deteriorated (>10% increase in MAP/increase in drugs/>20% reduced GFR), improved (>10% reduced MAP/reduced drugs/>20% increased eGFR), or stabilized (<10% change in MAP/same antihypertensive drugs/<20% change in eGFR) at last follow‐up. A total of 220 subjects with mean age of 57.6 ± 10.4 years underwent PTA and/or stenting. The average follow‐up was 23.07 ± 21.2 months. Accelerated HTN, HTN onset >50 years, unexplained renal failure, and unilateral small kidney were the most common presentations. In all, 255 significant stenotic lesions in 220 patients (119 unilateral, 66 single functioning kidney, and 35 bilateral) were observed. In total, 255 PTA were performed, including 177 stenting. Technical success was seen in 220/243 (90.5%) subjects. Combined MAP and antihypertensive drugs improved in 154/220 (70%) patients. Renal function improved/stabilized in 175/220 (79.5%). Angioplasty and stenting are relatively safe and feasible tools for control of blood pressure (BP) in ARAS. Angioplasty produced improvement/stabilization of BP in 70%, and the renal function in 79.5% subjects.  相似文献   
58.
Introduction The Fontan procedure has undergone many modifications to avoid atrial arrhythmias and thrombus formation. We used patient’s interatrial septum as a flap to direct the inferior venacaval blood to the superior venacava. Methods Seventeen patients, aged 1 to 17 years, underwent modified total cavopulmonary anastomosis. Interatrial septum was used to create the inner half of the atrial tunnel, outer half being formed by right atrial free wall. Post-operatively, all patients underwent echocardiography. Seven patients underwent 24 hour ambulatory Holter monitoring and 6 patients underwent cardiac catheterization and cineangiography. Results There was one early death due to low cardiac output. One patient had transient supraventricular arrhythmia. Two patients had singnificant pleural effusion. Holter Monitoring reveled sinus rhythm in all 7 patients studied. Follow up ranged from 18 to 60 months and patients were evaluated as they came for follow up. Long term follow up is currently being compiled. There was one late death from a non-cardiac cause. The remaining patients were in New York Heart Association (NYHA) Class I or II. All patients were in sinus rhythm. Echocardiography and cineangiography revealed absence of obstruction or leak. Conclusions Total cavopulmonary anastomosis using autogenous atrial septum is a useful modification for classical cavopulmonary anastomosis and provides good early results.  相似文献   
59.
促红细胞生成素对实验性肾性贫血的作用   总被引:1,自引:0,他引:1  
促红细胞生成素(erythropoietin,EPO)是由肾细胞分泌的一种糖蛋白激素。从人胚肾细胞中诱导,经生物化学方法分离、提纯得到此品。本试验用5/6肾切除的方法造成大鼠慢性肾衰性(CRF)贫血,研究不同剂量EPO对CRF贫血的作用。结果表明EPO有显著的促进红细胞生成,改善CRF贫血状态,使其接近或达到正常水平,最佳剂量为1000 U/kg,并可预防实验性贫血,对正常鼠未见明显作用。  相似文献   
60.
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