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491.
OBJECTIVES: This study aimed to evaluate the relationship between anemia and heart failure (HF) prognosis. BACKGROUND: Although it is known that chronic diseases, including HF, may be associated with anemia, the impact of hemoglobin (Hb) level on symptoms and survival in HF has not been fully defined.We analyzed a cohort of 1,061 patients with advanced HF (New York Heart Association [NYHA] functional class III or IV and left ventricular ejection fraction [LVEF] <40%) referred to a single center for evaluation and management. The Hb level was drawn at time of initial evaluation. Patients were divided into quartiles of Hb: Hb <12.3; Hb 12.3 to 13.6; Hb 13.7 to 14.8; Hb >14.8 g/dl. RESULTS: Mean Hb was 13.6, and values ranged from 7.1 to 19.0 g/dl. The Hb groups were similar in age, medication profile, LVEF, hypertension, diabetes, smoking status and serum sodium. Lower Hb was associated with an impaired hemodynamic profile, higher blood urea nitrogen and creatinine, and lower albumin, total cholesterol and body mass index. Patients in the lower Hb quartiles were more likely to be NYHA functional class IV (p < 0.0001) and have lower peak oxygen consumption (PKVO(2)) (p < 0.0001). Survival at one year was higher with increased Hb quartile (55.6%, 63.9%, 71.4% and 74.4% for quartiles 1, 2, 3 and 4, respectively). On multivariate analysis adjusting for known HF prognostic factors, low Hb proved to be an independent predictor of mortality (relative risk 1.131, confidence interval 1.045 to 1.224 for each decrease of 1 g/dl). CONCLUSIONS: In chronic HF, relatively mild degrees of anemia are associated with worsened symptoms, functional status and survival.  相似文献   
492.
The dose-rate effect in human tumour cells   总被引:4,自引:0,他引:4  
The radiation response of 12 cell lines derived from a variety of human tumours has been investigated over the dose-rate range from 150 to 1.6 cGy/min. As the dose rate was lowered, the amount of sparing varied widely; in 2 cell lines it was zero, in the other cell lines the dose required for 10(-2) survival ranged up to twice the value at high dose rate. Low dose-rate irradiation discriminates better than high dose rate between tumour cell lines of differing radiosensitivity. The data are equally well fitted by two mathematical models of the dose-rate effect: the LPL model of Curtis and the Incomplete Repair model of Thames. Analysis by the LPL model leads to the conclusion that the theoretical radiosensitivity in the total absence of repair was rather similar among the 7 cell lines on which this analysis was possible. What differs among these cell lines is the extent of repair and/or the probability of direct infliction of a non-repairable lesion. Recovery from radiation damage was also examined by split-dose experiments in a total of 17 human tumour cell lines. Half-time values ranged from 0.36 to 2.3 h and there was a systematic tendency for split-dose halving times to be longer than those derived from analysis of the dose-rate effect. This could imply that cellular recovery is a two-component process, low dose-rate sparing being dominated by the faster component. The extent of low dose-rate sparing shows some tendency to correlate with the magnitude of split-dose recovery; in our view the former is the more reliable measure of cellular recovery. The clinical implication of these studies is that some human tumour types may be well treated by hyperfractionation or low dose-rate irradiation, while for others these may be poor therapeutic strategies.  相似文献   
493.
How to cite this article: Anand A, Nair RR, Kodamanchili S, Panda R, Bhardwaj KK, Gowthaman TB. Communication with Patients on Mechanical Ventilation: A Review of Existing Technologies. Indian J Crit Care Med 2022;26(6):756–757.  相似文献   
494.
Ocrelizumab, an anti-CD20 monoclonal antibody, counteracts induction of humoral immune responses after severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccinations in patients with multiple sclerosis (MS). We aimed to assess if serum ocrelizumab concentration measured at the time of vaccination could predict the humoral response after SARS-CoV-2 vaccination. In 52 patients with MS, we found ocrelizumab concentration at the time of vaccination to be a good predictor for SARS-CoV-2 IgG anti-RBD titers after vaccination (comparable to B-cell count). As the course of ocrelizumab concentration may be predicted using pharmacokinetic models, this may be a superior biomarker to guide optimal timing for vaccinations in B-cell depleted patients with MS. ANN NEUROL 2023;93:103–108  相似文献   
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