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1.
The incidence of congenital rubella was found to be 2.3 times higher in Asian than non-Asian births in England and Wales. This was attributed in part to higher susceptibility to rubella in Asian than non-Asian women, as shown by antenatal serological data from public health laboratories in Leeds, Luton, and Manchester. Examination of the ethnic origin of pregnant women requesting laboratory testing after contact with rubella or rash and of women with laboratory confirmed rubella in pregnancy also suggested that the disease was being underdiagnosed in pregnant Asian women. Failure to prevent congenital rubella by termination of infected pregnancies may therefore contribute to the increased incidence of the syndrome in Asians. Health education programmes about the dangers of rubella in pregnancy and of the need for vaccination can readily be promoted in the Asian community through existing ethnic organisations. Protection of other ethnic minorities likely to be at similar increased risk may require a vaccination programme aimed at national elimination of rubella.  相似文献   
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Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI.  相似文献   
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Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time.  相似文献   
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Hypoxic proliferation of pulmonary arterial smooth muscle cells (PASMC) is mitogen dependent, but the signaling pathways mediating hypoxia-induced cell growth are not well understood. We investigated hypoxic proliferation in primary cultures from porcine pulmonary artery smooth muscle. The cells were grown in medium with or without platelet-derived growth factor (PDGF)-B, a potent smooth muscle cell mitogen. Hypoxia induced upregulation of PDGF receptor-beta expression, the primary receptor for PDGF-B. However, PDGF-B-mediated hypoxic enhancement of proliferation was abolished by pertussis toxin, indicating (1) involvement of heterotrimeric Galpha i proteins and (2) minimal effect of increased PDGF receptor expression in hypoxic enhancement of proliferation. We treated PASMC with labeled, nonhydrolyzable analogs of GTP to determine directly if GTP binding proteins were activated by hypoxia in PASMC. We show that hypoxia stimulates GTP incorporation in PASMC both in the presence and absence of PDGF-B. Serum-starved PASMC are able to increase their incorporation of GTP after only 10 min of hypoxia, and this response is not pertussis toxin sensitive. In serum-starved PASMC, we show that hypoxia stimulates incorporation of GTP into a 44-kD protein. The results show that heterotrimeric G proteins are involved in hypoxia-induced signaling in pulmonary vascular smooth muscle cells.  相似文献   
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BackgroundCirrhotics often demonstrate worse outcomes than their non-cirrhotic counterparts following orthopedic surgery; however, there are limited arthroplasty-focused data on this occurrence. Additionally, variances in postoperative outcomes among the different etiologies of cirrhosis have not been well described. The aim of this study is to evaluate the effect compensated cirrhosis had on postoperative outcomes following elective total knee arthroplasty (TKA).MethodsIn total, 1,734,568 patients who underwent primary TKA from 2006 to 2013 were identified using the Medicare Claims Database. Patients were divided into those with a history of compensated cirrhosis and those with no history of liver disease. Subgroup analysis was performed based on the etiology of cirrhosis. Multivariate logistic regression was used to evaluate postsurgical outcomes of interest.ResultsCirrhotic patients had higher risk of developing disseminated intravascular coagulation (odds ratio [OR] 2.76, P = .003), encephalopathy (OR 3.00, P < .001), and periprosthetic infection (OR 1.79, P < .001) compared to controls. Following subgroup analysis, alcoholic cirrhotics had high risk of periprosthetic infection (OR 2.12, P < .001), fracture (OR 3.28, P < .001), transfusion (OR 2.45, P < .001), and encephalopathy (OR 7.34, P < .001) compared to controls. Viral cirrhosis was associated with an increase in 90-day charges ($14,941, P < .001) compared to controls, while cirrhosis secondary to other causes was associated with few adverse outcomes compared to controls.ConclusionLiver cirrhosis is an independent risk factor for increased perioperative morbidity and financial burden following TKA. Cirrhosis due to etiologies other than viral infections and alcoholism are associated with few adverse outcomes. Surgeons should be aware of these complications to properly optimize postoperative management.  相似文献   
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BackgroundIron deficiency anemia (IDA) is a medical comorbidity commonly diagnosed in those undergoing primary total hip arthroplasty (THA). The authors sought to evaluate IDA as a risk factor for early postoperative complications following discharge and describe the hospital resource utilization of this patient population.MethodsPatients with a diagnosis of IDA who underwent THA from 2005 to 2014 were identified in a national insurance database. The rates of postoperative medical complications and surgery-related complications, as well as hospital readmission, emergency department visits, and death were calculated. Additionally, 90-day and day of surgery cost and length of stay were calculated. IDA patients were then compared to a 4:1 matched control population without IDA using a logistic regression analysis to control for confounding factors.ResultsIn total, 98,681 patients with a preoperative diagnosis of IDA who underwent THA were identified and compared to 386,724 controls. IDA was associated with increased risk of 30-day emergency department visits (odds ratio [OR] 1.35, P < .001) and 30-day readmission (OR 1.49, P < .001). IDA was also associated with an increased 90-day medical complication rate (cerebrovascular accident OR 1.11, P = .003; urinary tract infection OR 1.14, P < .001; acute renal failure OR 1.24, P < .001; transfusion OR 1.40, P < .001), as well as 1-year periprosthetic joint infection (OR 1.27, P < .001), revision (OR 1.22, P < .001), dislocation (OR 1.25, P < .001), and fracture (OR 1.43, P < .001). Patients with IDA accrued higher hospital charges ($27,658.27 vs $16,709.18, P < .001) and lower hospital reimbursement ($5509.90 vs $3605.59, P < .001).ConclusionPatients with preoperative IDA undergoing THA are at greater risk of experiencing early postoperative complications and have greater utilization of hospital resources.  相似文献   
9.
BackgroundAvian influenza A(H5N1) viruses have caused sporadic infections in humans and thus they pose a significant global health threat. Among symptomatic patients the case fatality rate has been ca. 50%. H5N1 viruses exist in multiple clades and subclades and several candidate vaccines have been developed to prevent A(H5N1) infection as a principal measure for preventing the disease.MethodsSerum antibodies against various influenza A(H5N1) clade viruses were measured in adults by ELISA-based microneutralization and haemagglutination inhibition tests before and after vaccination with two different A(H5N1) vaccines in 2009 and 2011.ResultsTwo doses of AS03-adjuvanted A/Indonesia/5/2005 vaccine induced good homologous but poor heterologous neutralizing antibody responses against different clade viruses. However, non-adjuvanted A/Vietnam/1203/2004 booster vaccination in 2011 induced very strong and long-lasting homologous and heterologous antibody responses while homologous response remained weak in naïve subjects.ConclusionsSequential vaccination with two different A(H5N1) pre-pandemic vaccines induced long-lasting high level cross-clade immunity against influenza A(H5N1) strains, thus supporting a prime-boost vaccination strategy in pandemic preparedness plans.  相似文献   
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Somatostatin and somatostatin analogues are considered very useful for the treatment of hormone producing tumors and acute variceal bleeding. They have also been proposed for the treatment of acute pancreatitis and for the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis although clinical trials have failed to show any efficacy. The authors report the case of a 45-year-old man, recently diagnosed of acromegaly, which developed an acute pancreatitis shortly after his first injection of lanreotide autogel. The patient developed a severe dilatation of his hypocontractile gallbladder with distension of the intra and extrahepatic biliary ducts, the choledochus and the main pancreatic duct, without lithiasis or other abnormalities at the papilla, which resolved spontaneously in a month. We consider that lanreotide most likely induced a functional spasm of the Sphincter of Oddi, with impairment of the biliary-pancreatic outflow, leading to an acute pancreatitis, and review the literature concerning this drug related pancreatitis.  相似文献   
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