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21.
Detection of respiratory syncytial virus antigen in nasal washings by Abbott TestPack enzyme immunoassay. 下载免费PDF全文
We compared the new Abbott TestPack (TP) respiratory syncytial virus (RSV) enzyme immunoassay (EIA) with cell culture and two commercial RSV EIAs (from Abbott Diagnostics and Kallestad Laboratories) by using split samples of fresh nasal washings from children with suspected RSV disease. Two tubes of HEp-2 cells were inoculated and observed for cytopathic effect for 14 days, and isolates were confirmed by immunofluorescence. The TP EIA was performed by following the manufacturer's instructions. Specimens positive by TP EIA but negative by culture were examined in a competitive inhibition (blocking) assay using the TP EIA, and rabbit anti-RSV serum. Of 218 specimens, 93 were positive by culture, 105 were positive by TP EIA, 80 were positive by the Abbott Diagnostics EIA, and 87 were positive by the Kallestad Laboratories EIA. The sensitivity, specificity, positive predictive value, and negative predictive value of the TP EIA were 92, 86, 81, and 93%, respectively. Of 20 apparently false-positive TP EIAs, 10 of 14 that were positive when retested were neutralized in the blocking assay, indicating that they were truly positive. The recalculated sensitivity, specificity, positive predictive value, and negative predictive value of the TP EIA were 92, 91, 90, and 93%, respectively. We conclude that the TP EIA is easy to perform, rapid (less than 0.5 h), and accurate. 相似文献
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Bernloehr C Bossow S Ungerechts G Armeanu S Neubert WJ Lauer UM Bitzer M 《Virus research》2004,99(2):193-197
Recombinant Sendai virus vectors (SeVV) have become an attractive tool for basic virological as well as for gene transfer studies. However, to (i) reduce the cellular injury induced by basic recombinant SeV vectors (encoding all six SeV genes as being present in SeV wild-type (wt) genomes) and to (ii) improve SeV vector safety, deletions of viral genes are necessary for the construction of superior SeVV generations. As a strong expression system recombinant replication-incompetent adenoviruses, coding for SeV proteins hemagglutinin-neuraminidase (HN), fusion (F), or matrix (M), were generated and successfully employed for the propagation of single gene deleted (DeltaHN, DeltaF, DeltaM) recombinant SeVV. Further investigations of the propagation procedures required for single gene deleted recombinant SeVV demonstrated (i) modifications of the cell culture medium composition as well as (ii) incubation with vitamin E as crucial steps for the enhancement of SeVV-DeltaHN, -DeltaF, or -DeltaM viral particle yield. Such optimized propagation procedures even led to a successful propagation of HN-deleted viral particles (SeVV-DeltaHN), which has not been reported before. 相似文献
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Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation. 相似文献
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Kathryn Lauer Charul Munshi Sanford Larson 《Journal of clinical monitoring and computing》1994,10(3):181-184
Objective. To quantify the effect of an induction dose of midazolam on median nerve somatosensory evoked potentials.Methods. We studied 10 patients undergoing lumbar spine surgery. After an induction dose of intravenous midazolam was given, MNEPs were collected for ten minutes. After ten minutes the patients were intubated and their anesthetic was supplemented with 0.5% isoflurane, narcotic, and N2O.Results. We found a clinically significant decrease in amplitude and an insignificant delay in latency.Conclusion. When midazolam is used as an anesthetic induction agent, a decrease in amplitude can be expected. 相似文献
26.
OBJECTIVE: Although the majority of evidence in rodents does not support the view that weight cycling (consisting of bouts of food restriction and refeeding) promotes obesity, the effects of weight cycling on body weight regulation remain controversial. We have previously demonstrated that some rats within a strain are more susceptible to develop obesity than others when given free access to a high-fat diet. In this study, we tested the hypothesis that rats most susceptible to weight gain on a high-fat diet would also be most susceptible to weight gain as a consequence of weight cycling. RESEARCH METHODS AND PROCEDURES: Rats were provided a low-fat diet (12% corn oil) for 2 weeks, then given a high-fat diet (45% corn oil) for 2 weeks to identify those most (obesity prone) and least (obesity resistant) susceptible to weight gain. Half of each group was then subjected to three 30-day cycles of food restriction (10 days) and refeeding (20 days) [weight cycler (WC) rats]. The other half were allowed free access to the high-fat diet [control (CO) rats]. All rats were then followed for an additional 10 weeks, with free access to the high-fat diet. RESULTS: When considering the entire 160 days of the study, we found no evidence that WC rats relative to CO rats had increased body weight, increased body fat content, or elevated energy efficiency. We found no evidence that rats most prone to dietary obesity were also prone to weight gain after weight cycling. During the weight cycling phase (days 1 to 90), weight cycled groups consumed less energy and gained less weight than controls. During the follow-up phase, WC and CO rats did not differ significantly in weight gain or energy intake. DISCUSSION: In this study, weight cycling did not exacerbate the obesity produced by high-fat diet feeding. 相似文献
27.
Grundy SM Blackburn G Higgins M Lauer R Perri MG Ryan D 《Medicine and science in sports and exercise》1999,31(11):1493-1500
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Minority status within any larger group is often difficult. Lesbian nurses face a dilemma of choice—whether or not to come out of the closet to their colleagues and patients. This essay describes the professional reflections of one lesbian nurse. 相似文献
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Paul C Rogers Thomas A Olson John W Cullen Deborah F Billmire Neyssa Marina Frederick Rescorla Mary M Davis Wendy B London Stephen J Lauer Roger H Giller Barbara Cushing 《Journal of clinical oncology》2004,22(17):3563-3569
PURPOSE: To determine whether children with localized gonadal malignant germ cell tumors (MGCT) stage II testicular and stages I and II ovarian treated with four cycles of standard-dose cisplatin combined with etoposide and low-dose bleomycin (PEB) have an event-free survival (EFS) of at least 85% without significant toxicity. PATIENTS AND METHODS: Between May 1990 and July 1995, eligible pediatric patients with stage II or recurrent from stage I (as a stage II) testicular MGCT and stages I and II ovarian MGCT were enrolled onto this Pediatric Oncology Group and Children's Cancer Group study. PEB chemotherapy consisted of bleomycin 15 U/m2 on day 1, cisplatin 20 mg/m2/d on days 1 to 5, and etoposide 100 mg/m2/d on days 1 to 5. Patients received four cycles of therapy at 21-day intervals. RESULTS: Seventy-four patients with a median age of 10.5 years (range, 8.7 months to 16.7 years) were enrolled. Primary sites included: stage II testicular (n = 17), stage I ovarian (n = 41), and stage II ovarian MGCT (n = 16). Treatment with standard PEB resulted in 6-year EFS of 95% and overall survival (OS) of 95.7%. EFS and OS by primary site were as follows: stage II testicular, 100% and 100%; stage I ovarian, 95.1% and 95.1%; and stage II ovarian, 87.5% and 93.8%, respectively. Two patients died from recurrent disease, and one patient died of secondary acute myelocytic leukemia. Infrequent grade 3 to 4 hematologic toxicity was reported. No grade 3 to 4 renal, pulmonary, or ototoxicity was observed. CONCLUSION: Combination chemotherapy with PEB results in excellent EFS and OS with minimal toxicity in children and adolescents with localized gonadal MGCT. 相似文献
30.