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1.

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   
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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   
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This study reports on beta 2-microglobulin (beta 2M) deposits in the skin of 12 uremic patients and three kidney transplant recipients compared with eight healthy controls. Uremic patients were treated by hemodialysis (HD), hemofiltration (HF), hemodiafiltration (HDF), or continuous ambulatory peritoneal dialysis (CAPD) for a period lasting from 1 to 19 years. Congo red staining of the skin was negative in patients and controls. However, immunofluorescent staining with an anti-beta 2-microglobulin monoclonal antibody was positive in the skin of all patients and of six of the eight controls. Beta 2M skin deposition is more intense in patients than in controls and increases with patient age and the duration of dialysis. A stron correlation is observed between the extent of skin beta 2M deposits and clinical manifestations due to beta 2M deposits in internal organs. However, no correlation is found between beta 2M skin deposits and sex or beta 2M serum levels.  相似文献   
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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   
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The aim of this study is to raise up the effect of surgical thrombectomy among other alternative therapies. This retrospective study reports 6 patients (mean age 63 years) admitted with phlegmasia cerulea dolens. All patients underwent surgical venous thrombectomy associated with infracava filter insertion in 2 cases. One patient died in the early postoperative course. In all other cases we noticed good early and late outcome both on clinical examination and duplex scanning assessment. In conclusion, surgical venous thrombectomy can be considered as a good and efficient procedure in the presence of phlegmasia cerulea dolens in order to relieve ischemia and to prevent whenever possible severe chronic venous disorders. However, fibrinolytic therapy might achieve as good results as surgery. Thus, the latter is to be reserved to very severe veinous ischemia with limb loss threatening where fibrinolytic therapy fails or is contre-indicated.  相似文献   
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Genetic polymorphisms in biotransformation enzyme CYP3A5 (6986G > A, CYP3A5*3; 14690A > G, CYP3A5*6) and drug transporter ABCB1 (1236C > T; 2677G > T/A; 3435C > T) are known to influence tacrolimus (Tac) dose requirements and trough blood levels in stable transplant patients. In a group of 19 volunteers selected with relevant genotypes among a list of 221 adult renal transplant candidates, we evaluated whether consideration of CYP3A5 and ABCB1 genetic polymorphisms could explain the interindividual variability in Tac pharmacokinetics after the first administration of a standard dose (0.1 mg/kg body weight twice a day). Lower area under the time versus blood concentration curves (AUC) or lower trough concentrations were observed among CYP3A5 expressors (n = 9) than among nonexpressors (n = 10) using two different analytical methods for Tac determination (liquid chromatography with tandem mass spectrometry (LC-MS/MS) and immunoassay). The median AUC(0-infinity) was 2.6- and 2.1-fold higher in nonexpressors for LC-MS/MS and immunologic methods, respectively. No difference was observed in Tac pharmacokinetic parameters in relation to ABCB1 polymorphisms. In conclusion, our study confirms the very significant effect of CYP3A5 polymorphism early after the first administration of Tac. It also provides a strong argument for a doubling of the loading dose in patients early identified a priori on the transplantation list as possessing at least one CYP3A5*1 allele.  相似文献   
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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   
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