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1.
In this paper we describe the design and synthesis of 18 derivatives of the antimicrobial atovaquone which were substituted at the 3-hydroxy group by ester and ether functions. The compounds were evaluated in vitro for their activity against the growth of Plasmodium falciparum, the malaria causing parasite. All the compounds showed potent activity, with IC50 values in the range of 1.25–50 nM, comparable to those of atovaquone and much higher than chloroquine or quinine.  相似文献   
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Local excision (LE) has arisen as an alternative to total mesorectal excision for the treatment of early rectal cancer. Despite a decreased morbidity, there are still concerns about LE outcomes.This systematic-review and meta-analysis design is based on the “PICO” process, aiming to answer to three questions related to LE as primary treatment for early-rectal cancer, the optimal method for LE, and the potential role for completion treatment in high-risk histology tumors and outcomes of salvage surgery.The results revealed that reported overall survival (OS) and disease-specific survival (DSS) were 71%–91.7% and 80%–94% for LE, in contrast to 92.3%–94.3% and 94.4%–97% for radical surgery. Additional analysis of National Database studies revealed lower OS with LE (HR: 1.26; 95%CI, 1.09–1.45) and DSS (HR: 1.19; 95%CI, 1.01–1.41) after LE. Furthermore, patients receiving LE were significantly more prone develop local recurrence (RR: 3.44, 95%CI, 2.50–4.74). Analysis of available transanal surgical platforms was performed, finding no significant differences among them but reduced local recurrence compared to traditional transanal LE (OR:0.24;95%CI, 0.15–0.4). Finally, we found poor survival outcomes for patients undergoing salvage surgery, favoring completion treatment (chemoradiotherapy or surgery) when high-risk histology is present.In conclusion, LE could be considered adequate provided a full-thickness specimen can be achieved that the patient is informed about risk for potential requirement of completion treatment. Early-rectal cancer cases should be discussed in a multidisciplinary team, and patient's preferences must be considered in the decision-making process.  相似文献   
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Dlk1 (Pref-1) is a transmembrane and secreted protein, which is a member of the epidermal growth factor-like family, homologous to Notch/Delta/Serrate. We have found by real-time RT-PCR that Dlk1 mRNA levels were high in CD34(+) cells in 10 of 12 MDS samples compared with CD34(+) cells from 11 normals. Also, Dlk1 mRNA was elevated in mononuclear, low density bone marrow cells from 11/38 MDS patients, 5/11 AML M6 and 2/4 AML M7 samples. Furthermore, 5/6 erythroleukemia and 2/2 megakaryocytic leukemia cell lines highly expressed Dlk1 mRNA. Levels of Dlk1 mRNA markedly increased during megakaryocytic differentiation of both CMK megakaryoblasts as well as normal CD34(+) hematopoietic stem cells. High serum levels of Dlk1 occurred in RA (4/10) and essential thrombocythemia (2/10) patients. Functional studies showed that forced expression of Dlk1 enhanced proliferation of K562 cells growing in 1% fetal bovine serum. Analysis of hematopoiesis of Dlk1 knockout mice suggested that Dlk1 contributed to granulocyte, megakaryocyte and B-cell clonogenic growth and was needed for generation of splenic B-cells. In summary, Dlk1 is overexpressed in selected samples of MDS (especially RA and RAEB) and AML (particularly M6, M7), and it appears to be associated with normal development of megakaryocytes and B cells.  相似文献   
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Introduction: People with dementia may be unable to verbally express pain and suffer from untreated pain. Use of analgesics in people with dementia has increased during the last decade, in particular opioid analgesics with high potential for adverse effects.

Areas covered: This article presents a systematic review of the current evidence for safety and tolerability of analgesic drugs from randomized controlled trials in people with dementia. Relevant trials were identified by a literature search in the EMBASE, MEDLINE, and Cochrane databases from inception to November 2018. The search included the main terms ‘dementia’ and ‘analgesic’ or their subterms, and was filtered to limit results to clinical trials.

Expert opinion: Although pain treatment is increasingly recognized as an important clinical issue in people with advanced dementia, there is currently a lack of evidence to support safety evaluations of commonly used analgesics in this group. To inform treatment decisions and enable care providers to appropriately monitor patients at risk of adverse effects, it is necessary to conduct well-designed clinical trials to investigate the relative efficacy and safety of analgesics in people with dementia, with particular emphasis on harmful effects of long-term opioid use as well as short-term use of nonsteroidal anti-inflammatory drugs.  相似文献   

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Objective: To investigate the impact of physical activity on asthma in middle-aged adults, in one longitudinal analysis, and one multi-centre cross-sectional analysis. Methods: The Respiratory Health in Northern Europe (RHINE) is a population-based postal questionnaire cohort study. Physical activity, height and weight were self-reported in Bergen, Norway, at RHINE II (1999–2001) and all centres at RHINE III (2010–2012). A longitudinal analysis of Bergen data investigated the association of baseline physical activity with follow-up asthma, incident asthma and symptoms, using logistic and zero-inflated Poisson regression (n = 1782). A cross-sectional analysis of all RHINE III centres investigated the association of physical activity with concurrent asthma and symptoms (n = 13,542) using mixed-effects models. Body mass index (BMI) was categorised (<20, 20–24.99, 25–29.99, 30+ kg/m2) and physical activity grouped by amount and frequency of lighter (no sweating/heavy breathing) and vigorous (sweating/heavy breathing) activity. Results: In the Bergen longitudinal analysis, undertaking light activity 3+ times/week at baseline was associated with less follow-up asthma (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.22, 0.89), whilst an effect from undertaking vigorous activity 3+ times/week was not detected (OR 1.22, 95% CI 0.44, 2.76). The associations were attenuated with BMI adjustment. In the all-centre cross-sectional analysis an interaction was found, with the association between physical activity and asthma varying across BMI categories. Conclusion: These findings suggest potential longer-term benefit from lighter physical activity, whilst improvement in asthma outcomes from increasing activity intensity was not evident. Additionally, it appears the benefit from physical activity may differ according to BMI.  相似文献   
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Real-time PCR based on the recN and gyrB genes was developed to detect four Streptococcus bovis/Streptococcus equinus complex (SBEC) subspecies from rectal swab specimens. The overall prevalence was 35.2%: Streptococcus gallolyticus subsp. gallolyticus (11.1%), S. gallolyticus subsp. pasteurianus (13%), Streptococcus infantarius subsp. coli (20.4%), and S. infantarius subsp. infantarius (11.1%). To conclude, these real-time PCR assays provide a reliable molecular method to detect SBEC pathogenic subspecies from rectal swab specimens.  相似文献   
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