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991.
Riata and Riata ST silicone defibrillation leads are prone to externalization of conductors due to inside-out abrasion in the high-voltage system, causing structural damage which may be accompanied by electrical failure. These situations are easily detected by fluoroscopy or radiology and by inspection of intracardiac electrograms and/or measurement of impedance. However, older pulse generators do not automatically perform all the measurements needed to assess the integrity of the high-voltage electrical system, nor do they have patient notifier alerts in case of dysfunction.The authors describe the case of a patient in whom structural damage was detected on fluoroscopy during pulse generator replacement. They discuss the best strategy in these patients, considering current knowledge of this dysfunction.  相似文献   
992.
Background and aimOffspring of women with gestational diabetes (GDM) exhibit an adverse cardiovascular risk factor profile by as early as age 5 years. Recently, maternal glycemia has been associated with epigenetic modification of genes on the fetal side of the placenta, including those encoding emerging risk factors (adiponectin, leptin), suggesting that vascular differences may emerge even earlier in life. Thus, we sought to evaluate cardiovascular risk factors and determinants thereof in 1-year-old infants of women with and without GDM.Methods and resultsTraditional (glucose, lipids) and emerging (C-reactive protein (CRP), adiponectin, leptin) risk factors were assessed in pregnancy in 104 women with (n = 36) and without GDM (n = 68), and at age 1-year in their offspring. In pregnancy, women with GDM had higher triglycerides (2.49 vs 2.10 mmol/L, p = 0.04) and CRP (5.3 vs 3.6 mg/L, p = 0.03), and lower adiponectin (7.3 vs 8.5 μg/mL, p = 0.04) than did their peers. At age 1-year, however, there were no differences in cardiovascular risk factors (including adiponectin) between the infants of women with and without GDM. Of note, maternal and infant adiponectin levels were associated in the non-GDM group (r = 0.39, p = 0.001) but not in the GDM group (r = 0.07, p = 0.67). Furthermore, on multiple linear regression analyses, maternal adiponectin emerged as an independent predictor of infant adiponectin in the non-GDM group only (beta = 776.1, p = 0.0065).ConclusionInfants of women with and without GDM have a similar cardiovascular risk factor profile at age 1-year. However, there are differences in their early-life determinants of adiponectin that may be relevant to the subsequent vascular risk of GDM offspring.  相似文献   
993.
Background and aimsWhether lipoprotein (a) [Lp(a)] concentration is associated with metabolic syndrome (MetS) and pre-clinical atherosclerosis in different ethnic groups is uncertain. The association between Lp(a), MetS and a measure of pre-clinical atherosclerosis was studied in a large Asian cohort.Methods and resultsData were analyzed from a South Korean occupational cohort who underwent a cardiac computed tomography (CT) estimation of CAC score and measurements of cardiovascular risk factors (n = 14,583 people). The key exposure was an Lp(a) concentration in the top quartile (>38.64 mg/dL)) with a CAC score >0 as the outcome variable and measure of pre-clinical atherosclerosis. Logistic regression was used to describe the associations. 1462 participants had a CAC score >0. In the lowest Lp(a) quartile (<11.29 mg/dL), 25.8% had MetS, compared with 16.1% in the highest Lp(a) quartile (>38.64 mg/dL (p < 0.001). MetS, and component features, were inversely related to Lp(a) concentration (all p < 0.0001). In the highest Lp(a) quartile group, there was an association between Lp(a) and CAC score >0 in men (OR 1.21[1.05, 1.40], p = 0.008), and women (OR 1.62[1.03, 2.55], p = 0.038), after adjustment for age, sex, lipid lowering therapy, and multiple cardiovascular risk factors. There was no evidence of an interaction between highest quartile Lp(a) and either high LDLc (>147 mg/dL) (p = 0.99), or MetS (p = 0.84) on the association with CAC score >0.ConclusionLp(a) levels are inversely related to MetS and its components. There was a robust association between Lp(a) concentration >38.6 mg/dL and marker of early atherosclerosis in both men and women, regardless of LDLc, level MetS or other cardiovascular risk factors.  相似文献   
994.
Cardiovascular disease (CVD) is a significant cause of death in Europe. In addition to patients with proven CVD, those with type 2 diabetes (T2D) are at a particularly high-risk of CVD and associated mortality. Treatment for dyslipidaemia, a principal risk factor for CVD, remains a healthcare priority; evidence supports the reduction of low-density lipoprotein cholesterol (LDL-C) as the primary objective of dyslipidaemia management.While statins are the treatment of choice for lowering LDL-C in the majority of patients, including those with T2D, many patients retain a high CVD risk despite achieving the recommended LDL-C targets with statins. This ‘residual risk’ is mainly due to elevated triglyceride (TG) and low high-density lipoprotein cholesterol (HDL-C) levels. Following statin therapy optimisation additional pharmacotherapy should be considered as part of a multifaceted approach to risk reduction. Fibrates (especially fenofibrate) are the principal agents recommended for add-on therapy to treat elevated TG or low HDL-C levels. Currently, the strongest evidence of benefit is for the addition of fenofibrate to statin treatment in high-risk patients with T2D and dyslipidaemia. An alternative approach is the addition of agents to reduce LDL-C beyond the levels attainable with statin monotherapy.Here, addition of fibrates and niacin to statin therapy is discussed, and novel approaches being developed for HDL-C and TG management, including cholesteryl ester transfer protein inhibitors, Apo A-1 analogues, mipomersen, lomitapide and monoclonal antibodies against PCSK9, are reviewed.  相似文献   
995.

Objective

An analysis of the timing of events is critical for a deeper understanding of the course of events within a patient record. The 2012 i2b2 NLP challenge focused on the extraction of temporal relationships between concepts within textual hospital discharge summaries.

Materials and methods

The team from the National Research Council Canada (NRC) submitted three system runs to the second track of the challenge: typifying the time-relationship between pre-annotated entities. The NRC system was designed around four specialist modules containing statistical machine learning classifiers. Each specialist targeted distinct sets of relationships: local relationships, ‘sectime’-type relationships, non-local overlap-type relationships, and non-local causal relationships.

Results

The best NRC submission achieved a precision of 0.7499, a recall of 0.6431, and an F1 score of 0.6924, resulting in a statistical tie for first place. Post hoc improvements led to a precision of 0.7537, a recall of 0.6455, and an F1 score of 0.6954, giving the highest scores reported on this task to date.

Discussion and conclusions

Methods for general relation extraction extended well to temporal relations, and gave top-ranked state-of-the-art results. Careful ordering of predictions within result sets proved critical to this success.  相似文献   
996.
文章对《口腔医学》2012年8月1日~2013年5月1日间391篇论文应用中国知网学术不端检测系统的检测结果进行分析,发现有14.58%的投稿文字复制比>30%?高复制比论文以临床研究为主,与同期投稿情况比较,综述?口腔正畸学论文出现高复制比的论文比例高于其他类型和学科的论文;复制来源于他人的期刊和学位论文较多,出现重合较多的部分主要是治疗或研究方法,以及讨论中的概念以及引证他人观点部分;其次是观察指标或者疗效评价标准?同时对学术不端的几个相关问题,如抄袭和合理引用?如何具体分析医学论文的复制部分?如何看  相似文献   
997.

Aim:

To explore the mechanisms underlying the protection by SO2 preconditioning against rat myocardial ischemia/reperfusion (I/R) injury.

Methods:

Male Wistar rats underwent 30-min left coronary artery ligation followed by 120-min reperfusion. An SO2 donor (1 μmol/kg) was intravenously injected 10 min before the ischemia, while LY294002 (0.3 mg/kg) was intravenously injected 30 min before the ischemia. Plasma activities of LDH and CK were measured with an automatic enzyme analyzer. Myocardial infarct size was detected using Evans-TTC method. The activities of caspase-3 and -9 in myocardium were assayed using a commercial kit, and the levels of p-Akt, Akt, PI3K and p-PI3K were examined with Western blotting.

Results:

Pretreatment with SO2 significantly reduced the myocardial infarct size and plasma LDH and CK activities, as well as myocardial caspase-3 and -9 activities in the rats. Furthermore, the pretreatment significantly increased the expression levels of myocardial p-Akt and p-PI3K p85. Administration of the PI3K inhibitor LY294002 blocked all the effects induced by SO2 pretreatment.

Conclusion:

The results suggest that the PI3K/Akt pathway mediates the protective effects of SO2 preconditioning against myocardial I/R injury in rats.  相似文献   
998.
The present study was designed to investigate the effect of CdCl2-polluted drinking water (40 mg CdCl2/L) on the level of TNF-α and IL-6, as well as oxidative status biomarkers in plasma of rats. The possible protective effect of oral administration of curcumin (50 mg/kg body weight/day) was assessed. Results illustrated that Cd exposure significantly elevated the plasma levels of TNF-α and IL-6 (p < 0.001) as compared to normal rats. Also, Cd administration resulted in a significant elevation in the lipid peroxidation and markedly reduction in the activities of SOD and catalase as well as the level of glutathione and total antioxidant capacity in plasma. The co-treatment of Cd with curcumin significantly reduced the levels of TNF-α and IL-6 and ameliorated the alteration in oxidative status biomarkers induced by Cd. Negative correlation between IL-6 or TNF-α was and the plasma activities of catalase, SOD and the level of total antioxidant capacity were found in rats exposed to Cd. Conclusion: Cadmium toxicity induced the release of TNF-α and IL-6 which is associated with systemic oxidative stress. This may be involved in the mechanism of the Cd toxicity. On the other hand, the findings suggest the curative action of curcumin against Cd toxicity.  相似文献   
999.
Ulvan extracted from Ulva pertusa (Chlorophyta) is a group of sulfated heteropolysaccharide, for simplicity, the sulfated polysaccharide is referred to as ulvan in this paper. To our knowledge, there is no detailed report investigating the toxicity of ulvan. In this study, the subchronic (6 months) toxicity of varying levels of ulvan extracted from U. pertusa was investigated in Wistar rats after oral administration. ALT, ALB, ALP, WBC, PLT, and liver relative organ weigh of female rats showed significantly difference at 3000 mg/kg body weight per day, compared with control group. On the other hand, TG, T-CHO concentrations of female rats (6 months) were significantly decreased at 600, 1200 and 3000 mg/kg body weight per day. This result proved that ulvan had antihyperlipidemic activity. Beside, ulvan showed anticoagulant activity in this study. Overall, our findings indicated that ulvan had affected specific hematology, serum biochemistry parameters and liver, and had great differences between males and females rats.  相似文献   
1000.
Diuron is carcinogenic to the rat urinary bladder at high dietary levels. The proposed mode of action (MOA) for diuron is urothelial cytotoxicity and necrosis followed by regenerative urothelial hyperplasia. Diuron-induced urothelial cytotoxicity is not due to urinary solids. Diuron is extensively metabolized, and in rats, N-(3,4-dichlorophenyl)urea (DCPU) and 4,5-dichloro-2-hydroxyphenyl urea (2-OH-DCPU) were the predominant urinary metabolites; lesser metabolites included N-(3,4-dichlorophenyl)-3-methylurea (DCPMU) and trace levels of 3,4-dichloroaniline (DCA). In humans, DCPMU and DCPU have been found in the urine after a case of product abuse. To aid in elucidating the MOA of diuron and to evaluate the metabolites that are responsible for the diuron toxicity in the bladder epithelium, we investigated the urinary concentrations of metabolites in male Wistar rats treated with 2500 ppm of diuron, the urothelial cytotoxicity in vitro of the metabolites and their gene expression profiles. DCPU was found in rat urine at concentrations substantially greater than the in vitro IC50 and induced more gene expression alterations than the other metabolites tested. 2-OH-DCPU was present in urine at a concentration approximately half of the in vitro IC50, whereas DCPMU and DCA were present in urine at concentrations well below the IC50. For the diuron-induced MOA for the rat bladder, we suggest that DCPU is the primary metabolite responsible for the urothelial cytotoxicity with some contribution also by 2-OH-DCPU. This study supports a MOA for diuron-induced bladder effects in rats consisting of metabolism to DCPU (and 2-OH-DCPU to a lesser extent), concentration and excretion in urine, urothelial cytotoxicity, and regenerative proliferation.  相似文献   
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