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排序方式: 共有2458条查询结果,搜索用时 468 毫秒
1.
Yinong Young-Xu Julia Thornton Snider Robertus van Aalst Salaheddin M. Mahmud Edward W. Thommes Jason K.H. Lee David P. Greenberg Ayman Chit 《Vaccine》2019,37(11):1484-1490
Background
Observational studies of the relative effectiveness of influenza vaccines are essential for public health decision making. Their estimates, however, are subject to bias due to unmeasured confounders. Instrumental variable (IV) methods can control for observed and unobserved confounders.Methods
We used linked electronic medical record databases in the Veterans Health Administration (VHA) as well as Medicare administrative files to examine the relative vaccine effectiveness (rVE) of high-dose influenza vaccine (HD) versus standard-dose influenza vaccines (SD) in preventing hospitalizations among VHA-enrolled Veterans ≥65?years of age during 5 influenza seasons (2010–2011 through 2014–2015). Using multivariable IV Poisson regression modeling to address unmeasured confounding and bias, we analyzed the data by each season and through longitudinal analysis of all five seasons.Findings
We included 3,638,924 person–influenza seasons of observation where 158,636 (4%) were among HD vaccine recipients and 3,480,288 (96%) were among SD vaccine recipients. Of the 1,728,562 Veterans, 1,702,824 (98.5%) were male and 1,299,412 (75%) were non-Hispanic white. Based on the longitudinal analysis of all five seasons, the IV-adjusted rVE estimate of HD vs. SD was 10% (95% CI, 8–12%) against all-cause hospitalization; 18% (95% CI, 15–21%) against cardiorespiratory-associated hospitalization; and 14% (95% CI, 6–22%) against influenza/pneumonia-associated hospitalization. The findings by season were similar.Interpretation
Our analysis of VHA clinical data collected from approximately 1.7 million Veterans 65?years and older during five seasons demonstrates that high-dose influenza vaccine is more effective than standard-dose influenza vaccines in preventing influenza- or pneumonia-associated hospitalizations, cardiorespiratory hospitalizations, and all-cause hospitalizations. 相似文献2.
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Ayman Agha Gabriel Glockzin Matthias Woenckhaus Wolfgang Dietmaier Igors Iesalnieks Hans J. Schlitt 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):671-677
Background Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with
an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore,
in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer.
Materials and methods The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma—8 patients with insular, 11 patients
with follicular, and 21 patients with papillary thyroid carcinomas—was compared. Disease-free survival and disease-specific
death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic
factors.
Results At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among
those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid
carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%).
Conclusion Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage
who have follicular or papillary thyroid carcinoma. 相似文献
6.
Phyllis W Sharps Ayman A E El-Mohandes M Nabil El-Khorazaty Michele Kiely Tessa Walker 《Journal of perinatology》2003,23(5):414-419
OBJECTIVE: To describe breastfeeding initiation among 210 urban African-American mothers with inadequate prenatal care. METHODS: This study is a case-control study of postpartum mothers recruited from four large urban hospitals. RESULTS: Mothers who chose to breastfeed were more educated, employed before birth, married, and using contraception postnatally. Regression model analysis controlling for demographic differences revealed that breastfeeding was significantly associated with a higher perception of severity of illness and higher confidence in the ability of health care to prevent illness. Breastfeeding mothers were less likely to reverse parent-child roles and had a lower perception of hassle from their infant's behavior. When comparing mothers who breastfed longer than 8 weeks to those who did not breastfeed, breastfeeding mothers had high scores related to empathy toward infants on the Adult-Adolescent Parenting Inventory as well as a low perception of hassle on the Parenting Daily Hassle. The perception of existing formal or informal social support did not influence breastfeeding behavior. CONCLUSION: Personal attributes of low-income urban mothers such as health beliefs and parental attitudes may play a role in the initiation and duration of breastfeeding. Low-income African-American mothers may be influenced in their choice to breastfeed by supportive messages from physicians and nurses delivering care to mothers and their newborns. Emphasis should be placed on the role breastfeeding can play in preventing childhood illnesses. 相似文献
7.
Ayman A Abdo Stefan J Urbanski Paul L Beck 《Journal canadien de gastroenterologie》2003,17(7):425-432
Microscopic colitis (MC) encompasses the two morphologically distinct entities of collagenous colitis (CC) and lymphocytic colitis (LC). MC was first described less than 30 years ago but is presently recognized as a relatively common cause of chronic diarrhea in the adult population. Remarkably, up to 10% of adults who have a colonoscopy for the investigation of chronic diarrhea, and have endoscopically normal appearing mucosa, may have MC. Patients with MC generally present with chronic diarrhea, which can be associated with cramping and bloating. Endoscopic and radiological examinations are usually normal. Histological assessment reveals inflammation consisting predominantly of lymphocytic infiltration, and a thickened subepithelial collagen band is diagnostic of CC. Both LC and CC can be associated with autoimmune diseases such as celiac disease, diabetes, arthritis and thyroiditis, yet the mechanisms involved in the pathogenesis remain unclear. Emerging studies suggest that a stepwise approach be taken in the medical management of MC. This approach includes antidiarrheal agents and stopping of any offending agents; budesonide or bismuth subsalicylate; and cholestyramine or 5-acetylsalicylic acid agents. In resistant cases, oral corticosteroids and other immune modulatory therapy have been used. 相似文献
8.
Ayman S Al Khadra Abdulaziz Al Jutaily Salem Al Shuhri 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(3):175-177
This report describes a patient with an implantable defibrillator who suffered an inappropriate defibrillation shock upon retrieving some food items from his inadequately earthed refrigerator. Noise typical of electrical interference can be observed in the stored electrogram of the episode. The patient was instructed to earth his home appliances, but he decided to avoid his refrigerator altogether, and has had no subsequent shocks. 相似文献
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Acute colonic pseudo-obstruction (ACPO), also known as Ogilvie’s syndrome, is a rare condition associated with massive dilatation
of the colon in the absence of any mechanical obstruction. Between 4 and 35% of all reported cases of ACPO have occurred in
association with pregnancy or puerperium, with most of these occurring after caesarean sections. We present a case report
of the successful management of a patient with ACPO. 相似文献