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In 1995, varicella vaccination was introduced into the infant immunization schedule of the United States. Currently, many other countries are considering mass varicella vaccination. Mass vaccination has two dangers: it could increase the number of varicella cases in adults, where severity is greater, and increase cases of zoster. A deterministic, realistic, age-structured model (RAS) was built to study these concerns. Model parameter estimates were derived from a review of the literature and surveillance data from England and Wales. Different vaccine efficacy scenarios, vaccine coverages, and vaccination strategies were investigated. The model predicts that, although an upward shift in the age at infection occurs, the overall morbidity due to varicella is likely to decrease following mass infant vaccination. On the other hand, cases of zoster may significantly increase in the first 50 years following vaccination. The model predicts that, in a population similar to England and Wales (50 m people), varicella vaccination with 90% coverage would prevent 0.6 m inpatient days due to varicella but would generate an extra 1.1 m inpatient days due to zoster over the first 65 years. Thus, under base-case model assumptions, the gain in reduction of varicella morbidity from infant vaccination is offset in the short-term by the increases in zoster morbidity (using inpatient days as a proxy). Paradoxically, less effective vaccines or vaccine programmes can be more effective in reducing overall morbidity (varicella + zoster) by allowing the virus to circulate more, which produces a smaller shift in the age at infection and a smaller increase in zoster cases. 相似文献
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996.
Dowdy SC Constantinou CL Hartmann LC Keeney GL Suman VJ Hillman DW Podratz KC 《Gynecologic oncology》2003,91(3):563-568
OBJECTIVE: Previous reports indicate that cytoreduction and salvage therapy with P32 or whole abdominal radiation may improve survival in patients with positive findings at second-look laparotomy (SLL). The aim of this investigation was to determine whether these findings held true with extended follow-up and a larger patient cohort. METHODS: From 1977 (the year platinum-based chemotherapy was introduced to our institution) to 1989, 150 patients had persistent disease at SLL. Relevant clinical information was extracted through retrospective chart review. RESULTS: One hundred forty-five patients were followed until death, with a median follow-up of 15.4 years for the 5 living patients. Median actuarial survival from the time of SLL was 18 months. Tumor grade (P = 0.003) and pre- and post-SLL tumor size (P < 0.0001) were significant determinants of survival by univariate analysis. Patients with microscopic disease or those with < or =1 cm disease rendered microscopic at SLL had improved survival relative to those with < or =1 cm and macroscopic disease following SLL (P = 0.03) (median survivals of 3.3, 2.5, and 1.4 years, respectively). In contrast, median survival of those with >1 cm disease cytoreduced to microscopic disease was no different than those with macroscopic residual, even if < or =1 cm (1.3 and 1.0 years, respectively). After adjusting for tumor size, salvage treatment was not a significant predictor of survival. CONCLUSION: With long-term follow-up there was no suggestion that the type of salvage therapy (e.g., P32 or WART) influenced survival. Rather, low-grade disease and low tumor burdens following cytoreduction were associated with improved survival on multivariate analysis. 相似文献
997.
Screening for fetal heart disease with ultrasound 总被引:7,自引:0,他引:7
998.
Costakos DT Greer FR Love LA Dahlen LR Suttie JW 《American journal of perinatology》2003,20(8):485-490
We studied babies (22 to 32 weeks gestational age) of mothers wishing to breast-feed. Group 1 received 1 mg of vitamin K and Group 2 received 0.5 mg of vitamin K. The Day 2 plasma levels of vitamin K were 1900 to 2600 times higher on average, and the Day 10 vitamin K levels 550 to 600 times higher on average, relative to normal adult plasma values, whether an initial prophylaxis dose of 0.5 mg or 1 mg was used. We conclude that 0.5 mg as the initial dose of vitamin K intramuscularly or intravenously would likely be more than adequate to prevent hemorrhagic disease of the newborn, and that 0.3 mg/per kg may be used for babies with birth weights below 1000 g. To decrease vitamin K intakes in this population, new preparations of total parenteral nutrition multivitamins are needed. 相似文献
999.
Jasper J Clark WD Cabrera-Meza G Berseth CL Fernandes CJ 《American journal of perinatology》2003,20(7):373-380
Much has been written on parental involvement in decision making when dealing with critically ill children, but few articles have touched upon parental refusal of treatment in noncritically ill children. What steps should be taken when a parent refuses what is generally considered "standard of care" medicine for their hospitalized child? Does medical advice outweigh parental views or wishes, and what does one do when our role as physician turns from medical expert into one of medical negotiator? The following case and discussion deal with parental refusal of conventional medical care, and how one may find peaceful resolutions to challenging situations for the ultimate good of the child. 相似文献
1000.
Nielsen PE Foglia LM Mandel LS Chow GE 《American journal of obstetrics and gynecology》2003,189(5):1257-1260
OBJECTIVE: This study was undertaken to estimate the reliability and validity of an objective structured assessment of technical skills (OSATS) for midline episiotomy repair using a lifelike anatomic model. STUDY DESIGN: Eighteen residents were administered an episiotomy OSATS. Two evaluators independently completed an objective score sheet assessing six key components of the repair, seven global surgical skills, and a pass/fail score for each resident. Residents also completed an anonymous self-assessment. RESULTS: Reliability indices were 0.95 for the checklist and global surgical skills rating. Construct validity found significant differences on the checklist, global surgical skills, and pass/fail score sheets by residency level. Residents more often assessed their own global surgical skills performance lower than the independent evaluators. Surprisingly, 61% (11/18) of the residents failed the assessment, including all postgraduate year 1 and postgraduate year 2 residents. CONCLUSION: Episiotomy OSATS that used task-specific and global checklists provide a reliable and valid method of assessing resident skills in this anatomic model, and performance correlates with resident year level of training. 相似文献