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A yellow fever immune serum was established in 1962 by the WHO Expert Committee on Biological Standardization as the International Reference Preparation of Anti-Yellow-Fever Serum, intended to serve as an immune reference serum in the mouse protection test used in the control of yellow fever vaccines.  相似文献   
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A purified, concentrated sheep vaccine, prepared from a vaccinia strain in use in the United Kingdom for more than 60 years, has been established as the International Reference Preparation of Smallpox Vaccine, intended to permit comparative assay with national reference vaccines.  相似文献   
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BACKGROUND: Exact mediastinal evaluation of patients with non-small-cell lung cancer (NSCLC) is mandatory to improve selection of resectable and curable patients for surgery. Mediastinoscopy (MS) and endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) are considered complementary, MS covering the anterior- and EUS-FNA the posterior mediastinum. Both methods can reach the paratracheal- and subcarinal-regions, but little is known about which method is most accurate, when compared in patients having both procedures performed. The aim of this study was to assess and compare the diagnostic value of MS and EUS-FNA with regard to mediastinal malignancy in the paratracheal- and subcarinal-regions. METHODS: Sixty patients considered to be potential candidates for resection of verified or suspected NSCLC underwent MS and EUS-FNA. The EUS-FNA diagnoses were confirmed either by open thoracotomy, MS or clinical follow-up. RESULTS: MS and EUS-FNA were conclusive for paratracheal or subcarinal mediastinal disease in 6 and 24 patients, respectively. Two patients with N2 disease diagnosed by EUS-FNA were upstaged to N3 by MS. The sensitivity for lymph node metastases in the right paratracheal region (2/4R) was 67% for EUS-FNA versus 33% for MS (p=0.69). In the left paratracheal region (2/4L) the sensitivity of EUS-FNA was 80% versus 33% for MS (p=0.06). In the subcarinal region (7) the sensitivity of EUS-FNA was 100% versus 7% for MS (p<0.01). The sensitivity for lymph node metastases in region 2/4L and/or 2/4R and/or 7 was 96% for EUS-FNA versus 24% for MS (p<0.01). CONCLUSION: In our hands EUS-FNA was superior to MS in the examination of paratracheal- and subcarinal-regions of patients considered for resection of lung cancer.  相似文献   
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Immunophenotyping of acute myeloid leukaemia (AML) has controversial implications with regards to prognosis. The aims of the present study were to determine the frequency of leukaemia‐associated phenotypes (LAP) in AML and to correlate their presence with response to induction chemotherapy. We analysed bone marrow samples at diagnosis from 84 AML patients using triple staining flow cytometry with routine standard panel of monoclonal antibodies. The association of LAP and response to induction chemotherapy was evaluated retrospectively. LAP were observed in 54 (64%) patients: lineage infidelity in 19 (35%), asynchronous antigen expression in 28 (52%), and lack of expected lineage specific antigens in 19 (35%). Significant correlation was found between LAP and responses to induction chemotherapy. Response to induction chemotherapy was more frequent in the absence of LAP (P < 0.05, estimated risk ratio of 1.6, 95%CI, 1.0–2.6) in a multivariate analysis. In conclusion, our data show the presence of LAP in AML is an independent predictor for response to induction chemotherapy and risk of relapse and should be considered for counselling patients and planning therapy.  相似文献   
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Background Identification of hospitalized carbapenem-resistant Enterobacteriaceae (CRE)-positive patient is important in preventing nosocomial transmission.The objective of this study was to illustrate the implementation of proactive infection control measures in preventing nosocomial transmission of CRE in a healthcare region of over 3200 beds in Hong Kong between October 1,2010 and December 31,2011.Methods The program included active surveillance culture in patients with history of medical tourism with hospitalization and surgical operation outside Hong Kong within 12 months before admission,and "added test" as an opportunistic CRE screening in all fecal specimens submitted to the laboratory.Outbreak investigation and contact tracing were conducted for CRE-positive patients.Serial quantitative culture was performed on CRE-positive patients and the duration of fecal carriage of CRE was analyzed.Results During the study period,a total of 6533 patients were screened for CRE,of which 76 patients were positive (10 from active surveillance culture,65 from "added test",and 1 secondary case from contact tracing of 223 patients with no nosocomial outbreak),resulting in an overall rate of CRE fecal carriage of 1.2%.The median time of fecal carriage of CRE was 43 days (range,13-119 days).Beta-lactam-beta-lactamase-inhibitors,cephalosporins,and fluoroquinolones were associated significantly with high fecal bacterial load when used 90 days before CRE detection,while use of cephalosporins,carbapenems,and fiuoroquinolones after CRE detection are significantly associated with longer duration of carriage.The duration of fecal carriage of CRE also correlates significantly with the initial fecal bacterial load (Pearson correlation:0.53; P=0.02).Conclusion Proactive infection control measures by enhanced surveillance program identify CRE-positive patients and data obtained are useful for the planning of and resource allocation for CRE control.  相似文献   
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Background: Erythropoietin (EPO) is a cytokine with organ‐protective properties. We hypothesized that EPO could attenuate acute renal dysfunction and inflammation in a porcine model of ischemia–reperfusion (IR). Furthermore, we aimed to characterize the impact of EPO on systemic and renal hemodynamics, and renal oxygen consumption. Methods: Twenty‐four pigs were randomly assigned to three groups: (1) EPO (5000 IU/kg) administered intravenously before IR (n=9), (2) placebo administered before IR (n=9), or (3) sham group, anesthetized and operated on only (n=6). IR was induced by clamping the left renal artery for 45 min. Hemodynamics and renal blood flow (RBF) were analyzed continuously. Glomerular filtration rate (GFR), renal oxygen consumption, and plasma cytokines (IL‐1β, IL‐6, IL‐8, IL‐10, and TNF‐α) were analyzed hourly. Renal biopsies were analyzed for cytokine content and apoptosis. Results: GFR was higher during reperfusion in the EPO group than in the placebo group (P<0.01). No differences between the IR groups were found in hemodynamics, RBF, oxygen consumption, or renal apoptosis. The levels of TNF‐α in the plasma (P=0.036) and the levels of TNF‐α and IL‐10 in the renal cortex (P=0.04 and P=0.01, respectively) were lower in the EPO group compared with the sham group. Conclusion: EPO attenuated the renal dysfunction as estimated as GFR. This effect was not related to changes in the hemodynamics. The immunomodulatory effects of EPO were manifested as decreased levels of TNF‐α and IL‐10 in renal biopsies and TNF‐α levels in plasma.  相似文献   
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Duchenne muscular dystrophy (DMD) is the most common X-linked neuromuscular disorder. The devastating nature of DMD has led to an intense effort toward finding a cure for this disease, dating back to the time when Duchenne first initiated clinical trials using faradic stimulation for DMD patients. Unfortunately despite the passage of some 150 years the disease remains incurable, and its medical management is largely supportive. However, the discovery of the DMD gene about 20 years ago has allowed a change in the focus of therapeutic strategy dramatically toward delivery of the missing gene/protein. Indeed, some degree of success has been achieved in preclinical animal studies using such strategies, and gene therapy trials are currently underway in humans. Pharmacological approaches for DMD are also being developed since they can circumvent some of the technical problems associated with gene and cell based therapy. This review explores developments in therapeutic approaches for DMD.Abbreviations BMD Becker muscular dystrophy - DAPC Dystrophin-associated protein complex - DMD Duchenne muscular dystrophy - DRP Dystrophin-related protein - IGF Insulin-like growth factor - mdx Dystrophin-deficient mouse - NMJ Neuromuscular junction - TGF Transforming growth factor S. Bogdanovich, K.J. Perkins contributed equally to this work  相似文献   
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