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1.
Notch signaling.   总被引:9,自引:0,他引:9  
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2.
Healthy aged adul (24–26 months of age) and young adult (2–4 months of age) C57BL/6J male mice were assessed for intermale aggression, pup-killing behavior (infanticide), and circulating levels of testosterone (T). When compared to young adult male mice, aged adult males were highly variable in the exhibition of both androgen-dependent behaviors. Significant numbers of aged males exhibited deficits in aggression and pup-killing while other animals were as behaviorally active as their young male counterparts. Assessment of serum T showed that aging did not produce a reduction in levels of the steroid and individual variability in androgen-dependent behavior of aged males was not related to plasma levels of the hormone. When aged non-aggressive and non-killer males were exposed to supplemental T by way of subcutaneously implanted silastic capsules, circulating levels of the steroid were elevated but T-dependent behavior was not recovered. These findings, in combination with those previously reported for copulatory behavior, indicate that the deficits observed in the androgen-dependent behavior of aged male mice cannot be attributed to a breakdown in the production of testicular androgens. While neural refractoriness to T may account in part for deficits in androgen-dependent behavior of aged males, the variability that is observed in the reproductive behaviors of aged male rodents ultimately may be related to other sources of variation such as perinatal environment.  相似文献   
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Racial/ethnic and socioeconomic disparities in COVID-19 burden have been widely reported. Using data from the state health departments of Alabama and Louisiana aggregated to residential Census tracts, we assessed the relationship between social vulnerability and COVID-19 testing rates, test positivity, and incidence. Data were cumulative for the period of February 27, 2020 to October 7, 2020. We estimated the association of the 2018 Social Vulnerability Index (SVI) overall score and theme scores with COVID-19 tests, test positivity, and cases using multivariable negative binomial regressions. We adjusted for rurality with 2010 Rural–Urban Commuting Area codes. Regional effects were modeled as fixed effects of counties/parishes and state health department regions. The analytical sample included 1160 Alabama and 1105 Louisiana Census tracts. In both states, overall social vulnerability and vulnerability themes were significantly associated with increased COVID-19 case rates (RR 1.57, 95% CI 1.45–1.70 for Alabama; RR 1.36, 95% CI 1.26–1.46 for Louisiana). There was increased COVID-19 testing with higher overall vulnerability in Louisiana (RR 1.26, 95% CI 1.14–1.38), but not in Alabama (RR 0.95, 95% CI 0.89–1.02). Consequently, test positivity in Alabama was significantly associated with social vulnerability (RR 1.66, 95% CI 1.57–1.75), whereas no such relationship was observed in Louisiana (RR 1.05, 95% CI 0.98–1.12). Social vulnerability is a risk factor for COVID-19 infection, particularly among racial/ethnic minorities and those in disadvantaged housing conditions without transportation. Increased testing targeted to vulnerable communities may contribute to reduction in test positivity and overall COVID-19 disparities.

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4.
Notch and the immune system   总被引:12,自引:0,他引:12  
Osborne B  Miele L 《Immunity》1999,11(6):653-663
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ContextThe comfort of patients with cancer near the end of life (EOL) is often undermined by unnecessary and burdensome treatments. There is a need for more research examining racial disparities in EOL care, especially in regions with a history of racial discrimination.ObjectivesTo examine whether black adults received more burdensome EOL care than white adults in a population-based data set of cancer decedents in Louisiana, a state with a history of slavery and long-standing racial disparities.MethodsThis was a retrospective analysis of EOL care from the Research Action for Health Network (REACHnet), a regional Patient-Centered Outcomes Research Institute-funded database. The sample consisted of 875 white and 415 black patients with metastatic cancer who died in Louisiana from 2011 to 2017. We used logistic regression to examine whether race was associated with five indicators of burdensome care in the last 30 days of life: chemotherapy use, inpatient hospitalization, intensive care unit admission, emergency department (ED) admission, and mechanical ventilation.ResultsMost patients (85.0%) received at least one indicator of burdensome care: hospitalization (76.5%), intensive care unit admission (44.1%), chemotherapy (29.1%), mechanical ventilation (23.0%), and ED admission (18.3%). Odds ratios (ORs) indicated that black individuals were more likely than white individuals to be hospitalized (OR = 1.66; 95% CI = 1.21–2.28; P = 0.002) or admitted to the ED (OR = 1.57; 95% CI = 1.16–2.13; P = 0.004) during their last month of life.ConclusionFindings have implications for informing health care decision making near the EOL for patients, families, and clinicians, especially in regions with a history of racial discrimination and disparities.  相似文献   
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Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF. Fifty-two consecutive patients (M/F = 39/13; 56 ± 11 years old) underwent clinical and echocardiographic evaluation, and blood sample collection at baseline. The same evaluation was repeated 6.4 ± 0.79 months after CRT. Patients with a decreased LV end-systolic volume by at least 15% (reverse remodeling) were considered echo responders to CRT. Twenty-nine patients (56%) were responders to CRT. After CRT, only 15 patients (29%) showed increased CT-1 after CRT. They were all non responders to CRT. A multivariate, logistic modelshowed CT-1 as an independent predictor of CRT echo response (p = 0.005; OR 0.97). During follow-up (18 ± 7 months), 21 cardiac events in 18 patients occurred. A Cox multivariable model showed plasma BNP pre-CRT (p = 0.02; CI 1.2–5.6; OR 3.1) and CT1 post-CRT (p = 0.01; CI 1.4–4.3; OR 2.7) as independent predictors of cardiac events. Analysis of CT-1 plasma levels deserves future consideration for larger, longitudinal studies in patients with CHF.  相似文献   
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