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101.
102.
BackgroundNeuropsychiatric complications of surgical coronary revascularization are inconspicuous but frequent and clinically relevant. So far, attempts to reduce their occurrence, such as the introduction of off-pump coronary artery bypass (OPCAB) grafting method, have not brought the desired results. The aim of this trial was to determine whether using any of the 2 selected modifications of OPCAB could decrease the incidence of these undesired sequelae.MethodsIn this single-center, assessor- and patient-blinded, superiority, randomized controlled trial, 192 patients scheduled for elective isolated OPCAB were randomized to 3 parallel arms. The control arm underwent “conventional” OPCAB with vein grafts. The first study arm underwent anaortic OPCAB (ANA) with total arterial revascularization. The second study arm underwent OPCAB with vein grafts using carbon dioxide surgical field flooding (CO2FF). Outcomes included the incidence of postoperative delirium (PD) and early postoperative cognitive dysfunction (ePOCD).ResultsThe incidence of PD was 35.9% in the control (OPCAB) arm, 32.8% in the CO2FF arm, and 12.5% in the ANA arm (χ2 [2, N = 191] = 10.17; P = .006). Post hoc tests revealed that the incidence of PD in the ANA arm differed from that in the OPCAB arm (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.09-0.68; P = .002). The incidence of ePOCD was 34.4% in the OPCAB arm, 28.1% in the CO2FF arm, and 9.5% in the ANA arm (χ2 [2, N = 191] = 11.58; P = .003). Post hoc tests revealed that the incidence of ePOCD differed between the ANA and OPCAB arms (OR, 0.20; 95% CI, 0.06-0.58; P < .001).ConclusionsPerforming ANA significantly decreases the incidence of PD and ePOCD compared with “conventional” OPCAB with vein grafts, whereas CO2FF is inconsequential in this regard. These results, which probably reflect decreased delivery of embolic load to the brain in ANA, may have practical applicability in daily practice to improve clinical outcomes.  相似文献   
103.
目的探究肺泡-动脉氧分压差(PA-aO2)、动脉血二氧化碳分压(PaCO2)和血乳酸(Lac)水平与急性百草枯中毒(APP)患者的预后的相关性。方法选取2018年8月至2020年8月就诊于本院的126例APP患者,根据3个月随访情况,分为存活组57例和死亡组69例,另选取同期于本院进行健康体检的健康人群45例作为对照组,检测3组PA-aO2、PaCO2和Lac水平。结果与对照组比较,APP患者PA-aO2和Lac水平显著升高,PaCO2水平显著降低,且死亡组变化幅度显著大于存活组,差异有统计学意义(P<0.05);PA-aO2和Lac与存活组呈负相关,与死亡组呈正相关,PaCO2与存活组呈正相关,与死亡组呈负相关(P<0.05);PA-aO2、PaCO2和Lac联合检测对APP患者预后的预测价值显著高于单一指标,差异有统计学意义(P<0.05)。结论PA-aO2、PaCO2和Lac水平与APP患者预后密切相关,值得临床参考。  相似文献   
104.
105.
The tricarboxylic acid (TCA) cycle performs an essential role in the regulation of energy and metabolism, and deficiencies in this pathway are commonly correlated with various diseases. However, the development of non‐invasive techniques for the assessment of the cycle in vivo has remained challenging. In this work, the applicability of a novel imaging agent, [1,4‐13C]‐diethylsuccinate, for hyperpolarized 13C metabolic imaging of the TCA cycle was explored. In vivo spectroscopic studies were conducted in conjunction with in vitro analyses to determine the metabolic fate of the imaging agent. Contrary to previous reports (Zacharias NM et al. J. Am. Chem. Soc. 2012; 134: 934–943), [13C]‐labeled diethylsuccinate was primarily metabolized to succinate‐derived products not originating from TCA cycle metabolism. These results illustrate potential issues of utilizing dialkyl ester analogs of TCA cycle intermediates as molecular probes for hyperpolarized 13C metabolic imaging. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
106.
碳纳米管(CNT)是一种具有特殊结构和性质的新型一维纳米材料。CNT具有优异的力学性能,良好的导热性能和极好的场致电子发射效应等优点,引起各国研究者的广泛关注。近年来,CNT在口腔医学领域的使用也逐渐增多,显示出良好的应用前景。本文就CNT的主要性能及其在口腔领域中应用作一综述。  相似文献   
107.
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.  相似文献   
108.
Abstract

Antihepatotoxic activity of a resuspended residue of the alcohol extract of Amoora rohituka W & A. (Meliaceae) was studied in rats with hepatic injury induced by carbon tetrachloride. Carbon tetrachloride (1 ml/kg, i.p.) was administered twice a week for 3 weeks and an extract of A. rohituka (50 mg/kg/day) was given orally for the same period. The rats were sacrificed 24 h after the last CC14 challenge. Carbon tetrachloride induced elevations of alkaline phosphatase (ALP), glutamate pyruvate transaminase (CPT), alanine aminotransferase (ALAT), glutamate oxaloacetate transaminase (GOT), aspartate aminotransferase (ASAT) and lactate dehydrogenase (LDH) and total plasma bilirubin concentration as well as depression of total plasma cholesterol concentration were reduced significantly by the concurrent treatment of rats with A. rohituka suspension. Changes in the histological architecture of the liver produced by CC14 where also protected by the administration of A. rohituka suspension. These results indicate that A. rohituka suspension possesses hepatoprotective action.  相似文献   
109.
《Pharmaceutical biology》2013,51(5):484-487
Tanshinone IIA (Tan IIA), one of the key components of Salvia milthorrhiza Bunge (Lamiaceae), is used to treat liver disease. The present study was carried out to investigate the possible mechanisms involved in the hepatoprotective effects of Tan IIA on carbon tetrachloride (CCl4)-induced hepatocyte toxicity. In cultures treated with 1 or 2 μM CCl4, Tan IIA (10–75 μM) significantly increased hepatocyte survival rates. However, only at a concentration of 75 μM could Tan IIA partially reverse the CCl4 (3 μM)-induced decrease of survival rate (34?±?3% vs. 18?±?3%, n?=?8, p?<?0.01). In isolated mitochondria energized with succinate, Tan IIA could inhibit the large swelling effect induced by CCl4 (1 and 2 μM). Base on these results, Tan IIA could protect rat primary cultured hepatocytes from CCl4-induced toxicity partially by the inhibitory effect on the opening of mitochondrial permeability transition (MPT).  相似文献   
110.
The current study is an effort to investigate the chemical constituents and antioxidant potential of Cnidoscolous chayamansa McVaugh (Euphorbiacea) root on carbon tetrachloride-induced liver damage. Albino rats were grouped into four: A - D. Groups A and B received 1?mL/kg BW of olive oil and 1?mL/kg body weight (BW) of carbon tetrachloride (CCl4), respectively, for 8 days while those in C and D received 1?mL/ kg BW each of CCl4 and 500 and 1000?mg/kg BW of aqueous extract of C. chayamansa root, respectively, for the same period. Chemical analysis of the plant root revealed the presence of tannins, phenolics, flavonoids, saponins, Fe, Zn, Mg, Ca, vitamins A and C. Administration of CCl4 resulted in significant increase (P?<0.05) in liver malondialdehyde concentration while the activities of liver alkaline phosphatase, superoxide dismutase, glutathione peroxidase and catalase were significantly reduced (P?<0.05). Simultaneous administration of CCl4 and the plant extract at 500 and 1000?mg/kg BW produced values of these biochemical parameters that compared favourably with the control (P?>0.05) in addition to increasing superoxide dismutase activity in the liver (P?<0.05). We conclude that aqueous extract of C. chayamansa root possessed antioxidant activity and protected the hepatocyte against CCl4-induced damage. The antioxidant activity of the plant may be due to its chemical constituents.  相似文献   
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