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The purposes of this investigation were to determine whether adults display alterations of cardiac rate under acoustical stimulus conditions and whether such alterations are influenced by signal level. The stimulus consisted of a narrow band of noise centered at 1000 Hz and presented at 20, 40, 60 and 80 dB SPL. The stimulus was found to produce alterations of heart rate significantly different from variation under non-stimulus conditions, indicating that cardiovascular responses occurred. However, the responses themselves were unaffected by differences of sound pressure level.  相似文献   
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The accuracy of the spot urine analyte/creatinine ratio in estimating 24‐hour excretion of the analyte is compromised because it is not adjusted for 24‐hour creatinine excretion. The authors developed a model for conveniently estimating 24‐hour creatinine excretion. The model was derived from 24‐hour urine collections using multiple linear regression, including sex, weight, race, and age. The model was then evaluated in a validation cohort, assessing the correlation between estimated and measured 24‐hour creatinine excretion and by comparing their correlation with muscle mass. Estimated creatinine excretion correlated strongly with measured creatinine excretion (r=0.80 in the entire cohort and 0.93 after eliminating patients with incomplete collections), and correlated at least as strongly as measured creatinine excretion with lean muscle mass (r=0.94 vs r=0.82, respectively). Adjusting spot urine analyte/creatinine ratios using the estimated 24‐hour creatinine excretion by this convenient method can improve the accuracy of estimating 24‐hour excretion of albumin, sodium, and other analytes.  相似文献   
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The alpha2 adrenergic receptor (α2-AR) antagonist yohimbine is a widely used tool for the study of anxiogenesis and stress-induced drug-seeking behavior. We previously demonstrated that yohimbine paradoxically depresses excitatory transmission in the bed nucleus of the stria terminalis (BNST), a region critical to the integration of stress and reward pathways, and produces an impairment of extinction of cocaine-conditioned place preference (cocaine-CPP) independent of α2-AR signaling. Recent studies show yohimbine-induced drug-seeking behavior is attenuated by orexin receptor 1 (OX1R) antagonists. Moreover, yohimbine-induced cocaine-seeking behavior is BNST-dependent. Here, we investigated yohimbine-orexin interactions. Our results demonstrate yohimbine-induced depression of excitatory transmission in the BNST is unaffected by alpha1-AR and corticotropin-releasing factor receptor-1 (CRFR1) antagonists, but is (1) blocked by OxR antagonists and (2) absent in brain slices from orexin knockout mice. Although the actions of yohimbine were not mimicked by the norepinephrine transporter blocker reboxetine, they were by exogenously applied orexin A. We find that, as with yohimbine, orexin A depression of excitatory transmission in BNST is OX1R–dependent. Finally, we find these ex vivo effects are paralleled in vivo, as yohimbine-induced impairment of cocaine-CPP extinction is blocked by a systemically administered OX1R antagonist. These data highlight a new mechanism for orexin on excitatory anxiety circuits and demonstrate that some of the actions of yohimbine may be directly dependent upon orexin signaling and independent of norepinephrine and CRF in the BNST.  相似文献   
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In recent years, several new classes of compounds have successfully been established in the treatment of cancer. They selectively inhibit disturbed signaling pathways or induce anti-tumor immune responses. These novel targeted cancer drugs show a favorable safety profile compared to conventional chemotherapeutic agents. The most important side effects of these anticancer agents include cutaneous reactions and occur in a time-dependant manner and show class-specific patterns. In this review article, we compare the cutaneous side effects of epidermal growth factor inhibitors (EGFRI), multikinase inhibitors (MKI), BRAF inhibitors (BRAFI), mTor inhibitors (mTorI) and immune checkpoint inhibitors and discuss severity-adapted management strategies.  相似文献   
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OBJECTIVES: We assessed the relationship of season and weather types with myocardial infarction (MI) and sudden cardiac death (SCD) in a geographically defined population, and tested the hypothesis that the increased risk in winter was related to weather. BACKGROUND: Winter peaks in coronary heart disease (CHD) have been documented. Yet, it is uncertain if seasonality exists for both incident events and deaths, and the role of weather conditions is not clear. METHODS: The daily occurrence of incident MI and SCD in Olmsted County was examined with data from the National Weather Service. Poisson regression models were used to assess the relative risks (RRs) associated with season and climatic variables. Subsequent analysis stratified SCD into those with and without antecedent CHD (unexpected SCD). RESULTS: Between 1979 and 2002, 2,676 MI and 2,066 SCD occurred. The age-, gender-, and year-adjusted RR of SCD, but not of MI, was increased in winter versus summer (1.17, 95% confidence interval [CI] 1.03 to 1.32) and in low temperatures (1.20, 95% CI 1.07 to 1.35, for temperatures below 0 degrees C vs. 18 degrees C to 30 degrees C). These associations were stronger for unexpected SCD than for SCD with prior CHD (p < 0.05). After adjustment for all climatic variables, low temperature was associated with a large increase in the risk of unexpected SCD (RR = 1.38, 95% CI 1.10 to 1.73), while the association with winter declined (RR = 1.06, 95% CI 0.83 to 1.35). CONCLUSIONS: These data suggest that the winter peak in SCD can be accounted for by daily weather.  相似文献   
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