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Recently, Laubender and Bender (Stat. Med. 2010; 29: 851–859) applied the average risk difference (RD) approach to estimate adjusted RD and corresponding number needed to treat measures in the Cox proportional hazards model. We calculated standard errors and confidence intervals by using bootstrap techniques. In this paper, we develop asymptotic variance estimates of the adjusted RD measures and corresponding asymptotic confidence intervals within the counting process theory and evaluated them in a simulation study. We illustrate the use of the asymptotic confidence intervals by means of data of the Düsseldorf Obesity Mortality Study. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Diane Santa Maria Charlene A. Flash Sarah Narendorf Anamika Barman-Adhikari Robin Petering Hsun-Ta Hsu Jama Shelton Kimberly Bender Kristin Ferguson 《The Journal of adolescent health》2019,64(5):574-580
Purpose
Evidence suggests that young adults experiencing homelessness (YEH) are at elevated risk of HIV compared to housed youth. Given the limited research on pre-exposure prophylaxis (PrEP) awareness among YEH, this study examined their PrEP knowledge and attitudes.Methods
Data from a cross-sectional survey among YEH (ages 18–26) (n?=?1,427) in seven U.S. cities were used to assess their knowledge and attitudes regarding PrEP to inform HIV prevention efforts.Results
Participants were primarily male youth of color. The mean age was 20.9years. While 66% felt at risk for HIV, only 14% strongly agreed that they try to protect themselves from getting infected with HIV. Most (84%) were eligible for PrEP based on risk, yet only 29% had knowledge of PrEP. Despite this, 59% reported they were likely/extremely likely to take PrEP. Access to free PrEP (55%), HIV testing (72%), healthcare (68%), and one-on-one (62%), and text messaging support (57%) were rated as very/extremely important for PrEP uptake and adherence.Conclusions
The results of this study suggest missed opportunities to prevent new HIV infections among YEH. Efforts to increase PrEP uptake among this population should consider provider- and system-level interventions to increase PrEP awareness, decrease PrEP-associated healthcare costs, improve access to PrEP providers, and provide in-person and text messaging support. 相似文献104.
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Jessica G.Y. Luc Michael A. Archer Rakesh C. Arora Edward M. Bender Arie Blitz David T. Cooke Tamara Ni Hlci Biniam Kidane Maral Ouzounian Thomas K. Varghese Mara B. Antonoff 《The Annals of thoracic surgery》2021,111(1):296-300
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Verónica Balaszczuk Crhistian Bender Germán Pereno Carlos A. Beltramino 《International journal of developmental neuroscience》2013
Mothers who consume alcohol during pregnancy may cause a neurotoxic syndrome termed fetal alcohol spectrum disorder (FASD) in the offspring, which includes cognitive deficits and emotional/social disturbances. These alterations are thought to be caused, at least in part, by alcohol-induced imbalance in neurotrophic factor levels, which are critically involved in normal neurodevelopment. Our goal was to study whether brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) expression were affected by alcohol in central extended amygdala (CEXA) and pyriform cortex (Pyr), structures strongly involved in emotional/social behaviors. Further, we evaluated how these changes could be related to blood and brain alcohol concentrations. Postnatal day (PND) pups at 7, 15 and 20-days old were administered alcohol (2.5 g/kg s.c. at 0 and 2 h) or saline. Immunohistochemistry was used to detect the expression of BDNF and GDNF at 2, 12 and 24 h after drug administration. Also, gas chromatography was bused to measure blood alcohol levels (BALs) and brain alcohol levels (BrALs) at each hour, from 2 to 8 h after the second alcohol administration. Results showed: (1) alcohol-induced enhancement of BDNF positive cells on PND 7 and 20, a decrease on PND 15 in the CEXA, and no changes in the Pyr on PND 7 and 20, but a diminished on PND 15; (2) GDNF positive cells rise after alcohol administration for the three ages in the CEXA and Pyr except on PND 15, where there was a decline; and (3) pharmacokinetics analysis demonstrated age-related differences showing equal BALs on PND 7 and 20 but higher BALs on PND 15. In contrast, BrALs were higher on PND 7 than 15 and 20. Hence, BALs may not be predictive of BrALs in postnatal rats. Furthermore, we did not find a relationship between age in pharmacokinetic differences and neurotrophins response. In conclusion, the CEXA and Pyr are brain structures sensitive to alcohol-induced imbalance in neurotrophic factors expression; and BALs are not a mirror of BrALs. 相似文献
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Sera from dogs rendered aplastic by total-body irradiation stimulate human bone marrow megakaryocyte progenitors to form megakaryocyte colonies in plasma clot cultures. In this investigation, we evaluated the effects of varying concentrations of such sera on both the mitotic and endomitotic phases of human megakaryocyte development in vitro. When low concentrations of aplastic canine sera (2.5% to 5.0% [vol/vol]) were added to cultures of human peripheral blood mononuclear cells in place of normal AB serum, megakaryocyte colony formation was augmented fivefold, cell numbers per colony increased approximately 2.5- fold, and the geometric mean megakaryocyte ploidy almost doubled. Further increasing the aplastic canine serum concentration from 10% to 30% (vol/vol) stimulated no additional colony formation. However, there was a further augmentation of cell numbers per colony associated with a progressive decrease in the mean megakaryocyte ploidy. Megakaryocyte cultures were harvested after 7, 12, 15, and 19 days of incubation, and these demonstrated that the lower mean ploidy values found at the higher concentrations of aplastic canine serum did not result from delayed endoreduplication. At all aplastic serum concentrations evaluated, there existed a strong correlation between nuclear ploidy and cell diameter. We conclude that both the mitotic and endomitotic events in human megakaryocytopoiesis may be influenced by a factor or factors present in aplastic canine serum. At lower in vitro concentrations, such sera stimulate both mitosis and endomitosis, which promotes the development of megakaryocyte colonies composed of larger cells with a higher mean ploidy. With increasing aplastic serum concentrations, colony formation plateaus and mitosis is favored over endomitosis. This results in colonies composed of more numerous but smaller megakaryocytes with a lower mean ploidy. Our data suggest that the size and extent of polyploidization that can be achieved by a developing megakaryocyte may be influenced by the mitotic prior history of its immediate precursor cell. 相似文献