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991.
Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase(PI3 K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3 K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting(GV24) and Baihui(GV20) acupoints, with a dilatational wave(1–20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3 K/Akt signaling pathwayrelated factors Beclin-1, mammalian target of rapamycin(mTOR), and PI3 K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3 K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting(GV24) and Baihui(GV20) acupoints activated the PI3 K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China(approval No. 8150150901) on March 10, 2016.  相似文献   
992.
目的 研究131I治疗分化型甲状腺癌(DTC)患者体内放射性活度及外部剂量水平的变化规律,分析二者之间的关系,并估算400 MBq患者剂量当量率的修正因子。方法 研究对象为43例甲状腺全切术后,首次行131I"清甲"治疗的DTC患者,服药量为1 850~3 700 MBq,平均服药量(2 405±777)MBq。分别于口服131I后2、6、20、22、24、27、30、44、46、48、54、68及72 h,测定患者的体内剩余放射性活度以及患者前部0.3、1及3 m处的剂量当量率。结果 患者服131I后的体内剩余放射性活度随时间变化函数为A=A0(1.033 16e-0.062 4t+0.017 17)。可估算出"清甲"治疗的DTC患者有效半减期为12.19 h,体内放射性活度降至400 MBq仅需26.4~38.9 h。患者服用131I后距其0.3、1及3 m的标准化剂量当量率随时间变化函数分别为:0.3=127.220 7e-0.054 8t+3.765 71、1=30.225 8e-0.064 4t+0.824 67、3=4.161 9e-0.061 5t+0.167 97。患者服131I后体内剩余放射性活度与1 m处剂量当量率呈正相关(r=0.982,P<0.05),函数为1=0.025A+1.245。DTC患者体内剩余活度分别为1 000、700和400 MBq时,距患者1 m处对应的剂量当量率分为26.2、18.7和11.2 μSv/h。估算活度为400 MBq的患者0.3、1及3 m处剂量当量率的修正因子分别为0.25、0.49及0.70。结论 服用131I活度在3 700 MBq以下的DTC患者仅需住院2日便可达到出院标准。当DTC患者体内活度降至400 MBq时,其1 m处的剂量当量率远小于25 μSv/h。单纯利用点源公式估算患者周围剂量当量率会造成高估的情况,因此对于公式估算患者周围辐射水平时使用的修正因子还需进一步研究,使模型估算结果更贴合实际情况。  相似文献   
993.
Background and aimsIdeal cardiovascular health (CVH) metrics was associated with stroke, but the causal pathway was poorly investigated. Arterial stiffness was a major factor associated with both ideal CVH metrics and stroke. This study aimed to investigate whether the effect of ideal CVH metrics on stroke was mediated and enhanced by arterial stiffness.Methods and resultsA total of 15,297 participants were included in current study. Arterial stiffness was measured by brachial–ankle pulse wave velocity (baPWV). Causal mediation analyses were used to separate the overall effects of ideal CVH metrics on stroke into indirect effects (mediated by arterial stiffness) and direct effects (mediated through pathways other than arterial stiffness). After a median follow-up of 5.88 years, 324 total stroke events (292 ischemic stroke and 31 hemorrhagic stroke) occurred. Mediation analysis showed 23.94% of the relation between ideal CVH and total stroke was mediated by baPWV (95% confidence interval [CI] of the indirect effect: 0.93–0.95). Further analysis showed the ideal CVH < median combined with baPWV ≥1400 cm/s was associated with the highest risk of total stroke (hazard ratio: 5.62; 95% CI, 3.53–8.96), compared with CVH ≥ median combined with baPWV < 1400 cm/s. Similar results were observed for ischemic stroke, but not for hemorrhagic stroke.ConclusionsArterial stiffness played a mediating role in the associations between ideal CVH metrics and risk of total and ischemic stroke. Combined ideal CVH metrics and baPWV is a reasonable and useful tool for the assessment and prevention of stroke.  相似文献   
994.
Background and aimsObservational studies have associated resting heart rate with incident diabetes. Whether the associations are causal remains unclear. We aimed to examine the shape and strength of the associations and assessed the causal relevance of such associations in Chinese adults.Methods and resultsThe China Kadoorie Biobank enrolled 512,891 adults in China. Cox proportional hazard regression models was conducted to estimate hazard ratios (HRs) for the associations of resting heart rate with type 2 diabetes and total diabetes. Among 92,724 participants, 36 single-nucleotide polymorphisms (SNPs) related to resting heart rate were used to construct genetic risk score. We used Mendelian randomization analyses to make the causal inferences. During a median follow-up of 9 years, 7872 incident type 2 diabetes and 13,349 incident total diabetes were documented. After regression dilution bias adjustment, each 10 bpm higher heart rate was associated with about a 26% higher risk of type 2 diabetes (HR, 1.26 [95% CI, 1.23, 1.29]) and 23% higher risk of total diabetes (HR, 1.23 [95% CI, 1.20, 1.26]). Instrumental variable analyses showed participants at top quintile compared with those at bottom quintile had 30% higher risk for type 2 diabetes (HR, 1.30 [95% CI, 1.17, 1.43]), and 10% higher risk for total diabetes (HR, 1.10 [95% CI, 1.02, 1.20]).ConclusionsThis study provides evidence that resting heart rate is an important risk factor for diabetes risk. The results suggest that novel treatment approaches targeting reduction of high heart rate for incidence of diabetes may be worth further investigation.  相似文献   
995.
996.
Congenital pyriform sinus fistula (CPSF) is a very rare branchial apparatus malformation. Traditional open surgery for fistulectomy might fail to excise the lesion completely, leading to continual recurrence. Herein, we report our experience of endoscopic coblation technique for treatment of CPSF in children.To observe the clinical efficacy of endoscopic coblation treatment of CPSF in children, especially for those in acute infection stage.Retrospective case series with 54 patients (including 20 cases in acute infection stage and 34 cases in non infection stage) who were diagnosed with CPSF between October 2017 to November 2019, all patients were treated with endoscopic coblation to close the piriform fossa fistula, neck abscess incision and drainage performed simultaneously for acute infection stage cases. Data collected including age of diagnosis, presenting symptoms, diagnostic methods, prior and subsequent treatments, length of hospitalization, and recurrence were analyzed.Of the 20 cases in acute infection stage, there were 3 children with transient vocal cord paresis all of which resolved with 1 month. Four children of the 34 cases in non infection stage appeared reddish swelling of the neck on the 4th, 5th, 6th, and 7th days after coblation and then underwent abscess incision and drainage. All cases experienced no recurrence, vocal cord paralysis, pharyngeal fistula and massive hemorrhage after their first endoscopic coblation of the sinus tract in the follow up of 3 to 28 months.Endoscopic coblation is an effective and safe approach for children with CPSF, neck abscess incision and drainage could be performed simultaneously in acute infection stage. We advocate using this minimally invasive technique as first line of treatment for CPSF.  相似文献   
997.
Epilepsy is a chronic neurological disorder that is characterized by episodes of seizure. Sexual dysfunction has been reported in patients with seizure, which mostly manifests as erectile dysfunction and premature ejaculation in men. In this study, we report the case of a 65-year-old Chinese man with frequent spermatorrhea. Electroencephalography suggested local epilepsy in the left temporal lobe. After treatment with anti-epilepsy drugs, the symptoms disappeared and did not recur. To the best of our knowledge, this is the first reported case of epilepsy-induced spermatorrhea. The symptoms of spermatorrhea are probably a rare manifestation of seizure. When repetitive stereotyped symptoms occur, seizure should be considered, and tentative anti-epileptic treatment may be a good option.  相似文献   
998.
ObjectiveFirst trimester screening is essential to preeclampsia (PE) prevention. Fetal Medicine Foundation (FMF) model combined maternal characteristics with mean arterial pressure (MAP), uterine artery pulsatility index (UtAPI) and placental growth factor (PlGF) to estimate risk. High detection rate (DR) was observed in Asia. The study aims to evaluate performance of screening in Taiwan.Materials and methodsThis was a prospective and non-interventional study between January, 2017 and June, 2018. Data was collected from 700 pregnant women at 11+0–13+6 gestational week. Maternal characteristics were recorded. MAP, UtAPI and PlGF were measured and converted into Multiple of the Median (MoM). Patient-specific risks were calculated with FMF model. Performance of screening was examined by ROC curve and DR.Results25 women (3.57%) contracted PE, including 8 with preterm PE (1.14%). In preterm PE, mean MoM of MAP and UtAPI were higher (1.096 vs 1.000; 1.084 vs 1.035). Mean MoM of PlGF was lower (0.927 vs 1.031). DR in preterm PE achieved 12.5%, 50.0%, 50.0% and 62.5% at false-positive rate (FPR) of 5%, 10%, 15% and 20%.ConclusionFMF model showed high DR for PE in Taiwan. Integration of PE and Down screening could set up a one-step workflow.  相似文献   
999.
The heme oxygenase gene has antioxidant and cytoprotective effects in organisms, but no related research has been conducted in Ganoderma lucidum. For the first time, we cloned the HMX1 gene in G. lucidum. The CDS is 1092 bp in length and encodes 363 amino acids. The HMX1 protein was prokaryotically expressed and purified, and the enzyme activity of the purified protein was measured. The value of Km was 0.699 μM, and Vm was 81.9 nmol BV h−1 nmol−1 protein. By constructing the silencing vector pAN7-dual-HMX1i, the transformants HMX1i1 and HMX1i2 were obtained. Compared with the wild-type (WT), the average growth rate of HMX1i1 and HMX1i2 decreased by 31% and 23%, respectively, and the mycelium biomass decreased by 53% and 48%, respectively. Compared with the WT, the extracellular polysaccharide content of HMX1i1 and HMX1i2 increased by 59% and 51%, and the intracellular polysaccharide content increased by 24% and 22%, respectively. These results indicate that the HMX1 gene affects mycelial growth and polysaccharide synthesis in G. lucidum.  相似文献   
1000.
王雨萌  魏欣  王婧  鲁晨  费凡  韩冰 《口腔医学》2021,41(9):843-846
SOX2基因在胚胎干细胞的多能性及机体发育过程中起到重要作用,也是常见的肿瘤干细胞标志物之一,近年来研究证实,肿瘤干细胞与癌症的发生发展与转移扩散密切相关.本文就SOX2基因在头颈部鳞状细胞癌中早期诊断、增殖转移、预后及治疗等方面的机制和作用作一综述.  相似文献   
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