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The occurrence of infection with a parvovirus-like agent during the period April 1979-May 1981 in children attending a single sickle cell clinic in London was investigated. Virus was detected in serum by counter-current immunoelectrophoresis (CIE) and immunoelectron microscopy (IEM). Viral antibody was detected by CIE and specific IgM antibody by an IgM-antibody capture assay. Of the 68 children studied nine presented in aplastic crisis and evidence of infection with the parvovirus-like agent at the time of the crisis was found in all nine. Eighteen of the other children were antibody-positive at some time during the study. In 11 children there was no evidence of recent infection; however, two of these had a history of aplastic crisis in previous years. The other seven seroconverted during the course of the study but did not show any haematological effects. Five of these had a primary infection, one appeared to have reinfection and in the seventh there were insufficient data to distinguish between the two. Possible explanations for the difference between those presenting with aplastic crisis and those with asymptomatic seroconversion are discussed.  相似文献   
14.
Evolutionary silencing of the human elastase I gene (ELA1)   总被引:6,自引:0,他引:6  
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Summary A well characterized strain of guinea pig cytomegalovirus (GPCMV) was used to infect pregnant guinea pigs during various periods of pregnancy. Transplacental transmission of virus with invasion of the fetus was observed, even in some mothers with preinoculation evidence of GPCMV antibody. Fetal infection occurred during the middle third of pregnancy and GPCMV was isolated from many fetal tissues although histologic evidence of infection was not noted. During the last third, abortion of the pregnancy occurred in some animals.This report demonstrates that GPCMV may invade the fetus producing a sublethal, possibly mild infection which may be very similar to the usual type of CMV infection observed in the human newborn.  相似文献   
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PurposeWe aimed to assess the prognostic value of Neutrophil to Lymphocyte Ratio (NLR) on long-term outcomes and graft dysfunction after lung transplantation.MethodsWe retrospectively reviewed all patients receiving a lung transplant at our institution from 2011 to 2014. The primary exposure was elevated NLR at the time of transplant, defined by NLR>4. The primary outcomes were graft failure and three-year all-cause mortality. Multivariate logistic regression and Kaplan-Meier survival analysis were used to analyze outcomes.Results95 patients were included. 40 patients (42%) had an elevated NLR. Elevated NLR was associated with graft failure (OR: 4.7 [1.2–18.8], p = 0.02), and three-year mortality (OR: 5.4 [1.3–23.2], p = 0.03) on multivariate logistic regression. Patients with elevated NLR demonstrated significantly lower survival on Kaplan-Meier analysis (50% versus 74%, p = 0.02). The c-statistic for our multivariate model was 0.91.ConclusionElevated neutrophil to lymphocyte ratio is associated with poor long-term survival and graft failure after lung transplantation.  相似文献   
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BACKGROUND: Symptoms of cystic fibrosis (CF) may limit the utility of total body chlorine (TBCl) and total body potassium (TBK) measurements for assessing body fluid compartments of children. OBJECTIVE: This study assessed relations among independent measurements of TBCl, TBK, and total body water (TBW) in children with CF. DESIGN: We compared cross-sectional measurements of TBCl by in vivo neutron activation analysis, TBK by whole-body counting of (40)K, TBW by D(2)O dilution [TBW(D(2)O)], and TBW from TBCl and TBK [TBW(Cl + K)] in 19 prepubertal children (13 boys) aged 7.6-12.5 y who had mild symptoms of CF. Body-composition measurements were compared with data from previous studies of healthy children. RESULTS: Subjects with CF had deficits in TBCl, TBK, TBW, and body weight compared with control reference data (P < 0.05). The ratios (TBCl + TBK)/TBW and TBCl/TBK were not significantly different from control reference values, and plasma chlorine and potassium concentrations were within control reference ranges. The sum of TBCl and TBK correlated with TBW(D(2)O) (r(2) = 0.79, P < 0.001), and TBW(Cl + K) correlated with TBW(D(2)O) (r(2) = 0.78, P < 0.001). TBW(Cl + K) was similar to TBW(D(2)O) (mean +/- SEM: 19.0 +/- 0.5 compared with 19.4 +/- 0.5 L; NS). CONCLUSIONS: Prepubertal children with mild symptoms of CF can develop deficits in TBCl, TBK, and TBW that reflect chronic energy malnutrition. Mild symptoms of CF do not appear to affect normal relations among TBCl, TBK, and TBW. Measurements of TBCl and TBK may be used to assess body fluid compartments in these patients.  相似文献   
18.
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
19.
Non-typhoid Salmonella gastroenteritis   总被引:2,自引:0,他引:2  
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20.
BACKGROUND: Dialysis patients frequently present with debilitating coronary artery disease but are regarded as challenging patients for coronary artery bypass grafting. METHODS: The operative, early postoperative, and late results of 44 dialysis patients undergoing coronary artery bypass grafting from 1984 to 1997 were retrospectively reviewed. RESULTS: Compared with patients in The Society of Thoracic Surgeons database who underwent coronary artery bypass grafting, only cerebrovascular accident and postoperative cardiac arrest occurred more frequently in dialysis patients. However, 73% experienced some type of complication. Operative mortality was 11.4%. Decreased left ventricular ejection fraction and severe distal disease were predictive of increased operative mortality. New York Heart Association angina class fell from 2.8 to 1.5, and New York Heart Association congestive heart failure class fell from 2.6 to 1.8. Overall quality-of-life scores did not improve; however, walking distances remained consistently improved. Actuarial survival at 5 years was 32.0%+/-12.0%. Five-year survival was 0% for smokers and 83.6%+/-7.6% for nonsmokers (p = 0.0142). Causes of late death were myocardial infarction (4), sepsis (1), subdural hematoma (1), stroke (1), and unknown (6). CONCLUSIONS: Coronary artery bypass grafting should be avoided in dialysis patients with severe diffuse disease. A smoking history is associated with poor outcome. Coronary artery bypass grafting in dialysis patients is associated with a higher incidence of complications but can be performed with an acceptable operative mortality and is associated with good symptomatic relief of angina and heart failure.  相似文献   
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