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101.
In order to investigate new potential therapeutically active agents, we investigated the biological properties of two small libraries of quinoxalinones and 1,4‐benzoxazin‐2‐ones. The results obtained showed that compounds 5 , 9–11 have good cytotoxic activity against HeLa cells where the lowest IC50 value (10.46 ± 0.82 μM/mL) was measured for compound 10 . Additionally, the most active compounds ( 5 , 9 – 11 ) showed much better selectivity for MRC‐5 cells (up to 17.4) compared to cisplatin. In vitro evaluation of the inhibition of the enzyme α‐glucosidase showed that compounds 10 and 11 exert significant inhibition of the enzyme at 52.54 ± 0.09 and 40.09 ± 0.49 μM, respectively. Competitive experiments with ethidium bromide (EB) indicated that all tested compounds have affinity to displace EB from the EB‐DNA complex through intercalation, suggesting good competition with EB (Ksv = (3.1 ± 0.2), (5.1 ± 0.1), (5.6 ± 0.2), and (6.3 ± 0.2) × 103 M?1). A molecular docking study was also performed to better understand the binding modes and to conclude the structure–activity relationships of the synthesized compounds.
  相似文献   
102.

Objective

To identify possible predictors of post-cessation weight gain in smoking abstainers.

Patients and methods

A sample of 607 successful abstainers seen at the Centre for Tobacco-Dependent in Prague, Czech Republic, between 2005 and 2010, was included in this analysis. This sample was followed up for 1 year and included 47.9% women (N = 291) with the mean age of 48 years (18–85).

Findings

Post-cessation weight gain occurred in 88.6% of the 607 abstainers. The mean weight gain after one year post-quit was 5.1 kg (95% confidence interval 4.7–5.5 kg). Baseline characteristics associated with increased weight gain included a higher baseline smoking rate (p < 0.001), more severe cigarette dependence (p = 0.003), less physical activity (p = 0.008), and a report of increased appetite on the baseline assessment of withdrawal symptoms (p < 0.001).

Conclusions

Smokers who are more dependent and have minimal physical activity are at increased risk for post-cessation weight gain. For these smokers, incorporating interventions targeting the weight issue into tobacco dependence treatment is recommended. Further research should be done to identify reasons for this important quitting complication.  相似文献   
103.
Secondary-cast aluminum alloys have increasing industrial applications. Their biggest deficiency is their impurity content, especially Fe, which has low solubility in Al and almost all the content creates intermetallic phases. This work examines the effect of higher Fe content on the microstructure and properties of A356.0 alloy. At the same time, no other possibility existed to affecting the brittleness of the formation of the β phases. The calculation of Fecrit, ratio of Mn/Fe, quantitative and computed tomography analysis of porosity and Fe plate-like phases, measurement of mechanical and fatigue properties, and fractography analysis were performed in this study. The results show that gravity die casting into a sand mold, and the non-usage of Mn addition or heat treatment, do not have a negative effect on increasing the size of the Fe-rich plate-like phases. The longest Fe-rich phases have limited the pore growth and ratios, but their higher thickness led to greater porosity formation. The mechanical and fatigue properties correlate with the Fecrit level and the highest were for the experimental alloy with 0.454 wt.% of Fe. The experimental results confirmed the fact that if the Fe plate-like phases have a length of up to 50 µm, the fatigue properties depend more on the size of porosity. If the length of the Fe needles is more than 50 µm, then the properties are mainly affected by the length of these Fe phases.  相似文献   
104.
105.
It is well known that Chlamydia pneumoniae is an important respiratory pathogen. In this study, the prevalence of specific antibodies to C. pneumoniae in hospitalized patients with community-acquired pneumonia (943 adult females, 990 adult males and 185 children) was evaluated over a period of 7 y (1993-99). Two serum samples were obtained from all of the patients: 1 on admission and the other 3 weeks later. The specimens were tested for C. pneumoniae IgG, IgM and IgA antibodies by means of a microimmunofluorescence test. Acute infection with C. pneumoniae was determined in 9.4% of females and 13.1% of males. In children and adolescent patients, the microimmunofluorescence test showed recent infection in 8.6% of cases, with the highest prevalence occurring in the 11-15 y age group. The highest prevalence of C. pneumoniae pneumonia was found in 1995 and 1999: 15.4% and 13.6% respectively. The results obtained showed that C. pneumoniae is persistently present in the population of Slovenia.  相似文献   
106.
BACKGROUND: Hospital admissions for heart failure are common and readmission rates are high. Many admissions and readmissions may be avoidable, so that alternative strategies are needed to improve long-term management. METHODS: We conducted a randomized trial of the effect of a guideline-based intervention on rates of readmission within 90 days of hospital discharge and costs of care for patients who were hospitalized due to decompensated heart failure. The intervention consisted of comprehensive education of the patient and family, a prescribed diet and intensive application of guidelines' recommendations on pharmacological therapy. The intervention started before discharge and continued thereafter with follow-up visits for up to 3 months. Two hundred and nine guideline-managed patients were compared to 209 concurrent normally-discharged patients. RESULTS: Patients in the study group were more prescribed beta-blockers, ACE-inhibitors, angiotensin receptor blockers, and spironolactone. Sixteen patients (8%) in the intervention group and 31 (15%) among controls were readmitted for DRG 127, within 3 months of discharge (Fisher's exact test, p < 0.01), while the 6-month mortality rate was similar between groups (9 and 11.5% respectively). Quality of life significantly improved from 5.6 +/- 1.0 to 6.1 +/- 1.9 (Mann-Whitney U-test, p < 0.05). The overall costs of care were lower for guideline-managed patients (110 vs 150 Euro per patient per month), due to the lower readmission rates. CONCLUSIONS: Our study showed that a guideline-based management program for patients with heart failure at discharge improves quality of life and reduces readmission for DRG 127 and total bed days, allowing relevant cost savings.  相似文献   
107.

Background

South Asian ethnicity is an independent risk factor for mortality after coronary artery bypass. We tested the hypothesis that this risk results from a greater inflammatory response to cardiopulmonary bypass (CPB).

Methods

This was a single-site prospective cohort study. We compared the inflammatory response to CPB in 20 Caucasians and 17 South Asians undergoing isolated coronary artery bypass grafting surgery.

Results

Plasma levels of proinflammatory cytokines (interleukin [IL]-6, IL-8, IL-12, interferon gamma, and tumor necrosis factor) and anti-inflammatory mediators (IL-10 and soluble TNF receptor I) were measured. The Toll-like receptor (TLR) signaling pathway was examined in peripheral blood monocytes by flow cytometry, measuring surface expression of TLR2, TLR4, and coreceptor CD14 and activation of downstream messenger molecules (interleukin-1 receptor-associated kinase 4, nuclear factor kappa from B cells (NF-κB), c-Jun amino-terminal kinase, p38 mitogen-activated protein kinase, and Protein Kinase B). South Asians had persistently higher plasma levels of IL-6 and exhibited increased TLR signaling through the p38 mitogen-activated protein kinase and Protein Kinase B pathways in inflammatory monocytes after CPB. This increased inflammatory response was paralleled clinically by a higher sequential organ failure assessment score (5.1 ± 1.4 versus 1.5 ± 1.6, P = 0.027) and prolonged cardiovascular system failure (23.5% versus 0%) 48 h after CPB.

Conclusions

South Asians develop an exacerbated systemic inflammatory response after CPB, which may contribute to the higher morbidity and mortality associated with coronary artery bypass in this population. These patients may benefit from targeted anti-inflammatory therapies designed to mitigate the adverse consequences resulting from this response.  相似文献   
108.

Introduction

The aim of this study was to identify risk factors for severe postoperative pain immediately after hip-fracture surgery.

Patients and methods

Three hundred forty-four elderly patients with an acute hip fracture were admitted to the hospital during a 12-months period. All patients who entered the study answered a structured questionnaire to assess demographic characteristics, previous diseases, drug use, previous surgery, and level of education. Physical status was assessed through the American Society of Anesthesiologists’ preoperative risk classification, cognitive status using the Short Portable Mental Status Questionnaire, and depression using the Geriatric Depression Scale. The presence of preoperative delirium using the Confusion Assessment Method was assessed during day and night shifts until surgery. Pain was measured using a numeric rating scale (NRS). An NRS ≥7 one hour after surgery indicated severe pain.

Results

Patients with elementary-level education (8 yr in school) presented a higher risk for immediate severe postoperative pain than university-educated patients (>12 yr in school) (P < 0.05). Higher cognitive function was associated with higher postoperative pain (P < 0.01). Patients with symptoms of depression and patients with preoperative delirium presented a higher risk for severe pain (P < 0.05, P < 0.01, respectively). Multivariate analysis showed that depression and a low level of education were independent predictors of severe pain immediately after surgery.

Conclusion

Depression and lower levels of education were independent predictors of immediate severe pain following hip-fracture surgery. These predictors could be clinically used to stratify analgesic risk in elderly patients for more aggressive pain treatment immediately after surgery.  相似文献   
109.
110.
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