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31.
《Mayo Clinic proceedings. Mayo Clinic》2022,97(5):871-880
ObjectiveTo investigate whether artificial intelligence–enabled electrocardiogram (AI-ECG) assessment of atrial fibrillation (AF) risk predicts cognitive decline and cerebral infarcts.Patients and MethodsThis population-based study included sinus-rhythm ECG participants seen from November 29, 2004 through July 13, 2020, and a subset with brain magnetic resonance imaging (MRI) (October 10, 2011, through November 2, 2017). The AI-ECG score of AF risk calculated for participants was 0-1. To determine the AI-ECG-AF relationship with baseline cognitive dysfunction, we compared linear mixed-effects models with global and domain-specific cognitive z-scores from longitudinal neuropsychological assessments. The AI-ECG-AF score was logit transformed and modeled with cubic splines. For the brain-MRI subset, logistic regression evaluated correlation of the AI-ECG-AF score and the high-threshold, dichotomized AI-ECG-AF score with infarcts.ResultsParticipants (N=3729; median age, 74.1 years) underwent cognitive analysis. Adjusting for age, sex, education, and APOE ?4-carrier status, the AI-ECG-AF score correlated with lower baseline and faster decline in global-cognitive z-scores (P=.009 and P=.01, respectively, non–linear-based spline-models tests) and attention z-scores (P<.001 and P=.01, respectively). Sinus-rhythm-ECG participants (n=1373) underwent MRI. As a continuous measure, the AI-ECG-AF score correlated with infarcts but not after age and sex adjustment (P=.52). For dichotomized analysis, an AI-ECG-AF score greater than 0.5 correlated with infarcts (OR, 4.61; 95% CI, 2.45-8.55; P<.001); even after age and sex adjustment (OR, 2.09; 95% CI, 1.06-4.07; P=.03).ConclusionThe AI-ECG-AF score correlated with worse baseline cognition and gradual global cognition and attention decline. High AF probability by AI-ECG-AF score correlated with MRI cerebral infarcts. However, most infarcts observed in our cohort were subcortical, suggesting that AI-ECG not only predicts AF but also detects other non-AF cardiac disease markers and correlates with small vessel cerebrovascular disease and cognitive decline. 相似文献
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33.
《Dental materials》2022,38(2):242-250
ObjectiveTo study the mechanical behavior of endodontically-treated teeth with minimally invasive endodontic access cavities and resin composite restorations under different bonding conditions using finite element analysis (FEA).MethodsFour Class-II endodontic access cavities including the mesio-occlusal minimally-invasive (MO-MIE), mesio-occlusal conventional (MO-CONV), disto-occlusal minimally-invasive (DO-MIE), and disto-occlusal conventional (DO-CONV) cavities were prepared in 3D-printed maxillary first molars. Each tooth was subjected to root canal preparation and scanned using micro-CT to provide a 3D structural model which was virtually restored with resin composite. An intact 3D-printed molar was used as control. FEA was conducted under a 250-N vertical load. Three different interfacial bonding conditions between dentin/enamel and resin composite were considered, i.e. fully bonded, partially debonded, and fully debonded. The maximum principal stress of dentin and the normal tensile stress at the interfaces were recorded. The risk factor of failure for each component was then calculated.ResultsIn the fully-bonded tooth, the dentin-composite interface showed significantly higher stress and a higher risk factor than dentin, indicating that debonding at the dentin-composite interface would occur prior to dentin fracture. With the dentin-composite interface debonded, the enamel-composite interface exhibited higher stress and a higher risk factor than dentin, indicating that debonding at the enamel-composite interface would occur next, also prior to dentin fracture. With the resin composite fully debonded from the tooth, stress in dentin increased significantly. Irrespective of the bonding status, the CONV groups exhibited higher median stresses in dentin than the MIE groups.SignificanceWithin the limitation of this study, it was shown that debonding of the resin composite restoration increased the stress in dentin and hence the risk of dentin fracture in endodontically-restored teeth. Minimally-invasive access cavities could better safeguard the fracture resistance of interproximally-restored teeth compared to conventional ones. 相似文献
34.
杨红 《世界科学技术-中医药现代化》2022,24(8):3257-3262
目的 观察针药结合联合二甲双胍治疗多囊卵巢综合征不孕患者的临床疗效,并探讨其对子宫内膜容受性的影响。方法 将多囊卵巢综合征不孕患者90例随机分为对照组及观察组,对照组采用二甲双胍治疗,观察组在采用二甲双胍治疗的基础上,加用自拟补肾化痰活血方和针刺治疗,两组均治疗6个月,治疗结束后观察两组临床疗效,观察妊娠率及流产率,比较子宫内膜厚度及子宫动脉RI情况,比较治疗前后两组中医证候积分变化。结果 两组临床疗效的分布比较,差异具有统计学意义(P<0.05),观察组疗效优于对照组。①妊娠率:治疗后观察组的妊娠率高于对照组(P<0.05)。②流产率:治疗后观察组的流产率较对照组下降,但差异无统计学意义(P>0.05)。③子宫内膜厚度与子宫动脉RI:治疗后两组方案均能增加患者子宫内膜厚度、降低子宫动脉RI,且观察组较对照组子宫内膜增厚,子宫动脉RI降低(P<0.05)。④中医证候评分:治疗后观察组中医证候积分较对照组明显降低(P<0.01)。结论 针药结合联合二甲双胍能提高PCOS不孕患者妊娠率,降低流产率,其机制可能与改善子宫内膜容受性有关。 相似文献
35.
Though cerebrovascular complications of pregnancy remain relatively rare, they represent a potentially devastating event that necessitates prompt identification and treatment. Eighteen percent of strokes occurring in young women are linked to pregnancy. They occur mostly in the third trimester or during the post-partum period. Their biggest risk factors are hypertension, preeclampsia/eclampsia and migraine. Cerebrovascular events occurring during this period may involve specific pathophysiological processes that include embolic phenomena or endothelial dysfunction, but can also have common etiologies that are simply favored by the context of pregnancy. Thus, posterior encephalopathy and vasoconstriction cerebral syndrome are relatively frequently involved in cerebrovascular complications of pregnancy. Other very specific causes like amniotic fluid embolism or postpartum cardiomyopathy can also be responsible for such events. The management of stroke during pregnancy must be multidisciplinary and include a neurovascular expertise. Some conditions can lead to a long-life follow-up and modify the management of a future pregnancy. 相似文献
36.
The accessory glands of male moths secrete several proteins, which are known to affect post-mating behaviour in females such as calling, reduction in receptivity, rate of egg maturation and laying, sperm maintenance and release and formation of mating plug. Helicoverpa armigera (Hübner) is a polyphagous pest of numerous crops and it is widely distributed on the Indian subcontinent where it causes severe economic losses. In the present study, receptivity- and calling-inhibiting substance (RCIS), a peptide secreted from the accessory glands of male H. armigera, was sequenced, cloned and expressed in a prokaryote, Escherichia coli. RCIS is a peptide comprising 58 amino acids and had a theoretical molecular weight of 6.03 kDa. It showed 64% similarity with pheromonostatic peptide 1, identified in Helicoverpa zea (Kingan et al., 1995) but differed regarding deletion of four and one amino acids at positions 14–17 and 44, respectively, and insertion of one and five amino acids at position 38 and the terminal position of RCIS, respectively. H. armigera females injected with recombinant RCIS showed reduced receptivity and calling behaviour (in 70–80% of the treated individuals), and mating frequencies decreased by 80%. Recombinant RCIS may be employed to artificially induce non-receptivity in virgin females in order to prevent reproduction. 相似文献
37.
38.
Byeoung Hoon Chung Mi Rin Lee Jae Do Yang Hee Chul Yu Yong Tae Hong Hong Pil Hwang 《World Journal of Clinical Cases》2021,9(16):4104-4109
BACKGROUNDAn impalement injury of the oral cavity is a common traumatic injury in children. In most cases, it is not accompanied by sequelae, but if foreign body residues are not found due to a minor injury, they may result in inflammatory responses and delayed vascular injuries in the surrounding tissues. Without early diagnosis and appropriate initial management, residual foreign bodies can cause serious complications and even mortality in some cases. CASE SUMMARYA 9-year-old boy suffered an intra-oral injury by a wooden chopstick, and the patient was discharged from the hospital after receiving conservative treatment for the injury. However, the patient was readmitted to the hospital due to intra-oral bleeding, and since neck hematoma and right internal carotid artery pseudoaneurysm formation were detected on computed tomography, emergency surgery was performed. A remnant fragment of a wooden chopstick was found during the operation, and a delayed rupture of the internal carotid artery caused by the foreign body was also found.CONCLUSIONThe failure of early detection and diagnosis of a residual foreign body may result in delayed vascular rupture. 相似文献
39.
《Brain stimulation》2021,14(5):1307-1316
BackgroundThere is a lack of information regarding electrical properties of white matter and brain tumors.ObjectiveTo investigate the feasibility of in-vivo measurement of electrical resistivity during brain surgery and establish a better understanding of the resistivity patterns of brain tumors in correlation to the white matter.MethodsA bipolar probe was used to measure electrical resistivity during surgery in a prospective cohort of patients with brain tumors. For impedance measurement, the probe applied a constant current of 0.7 μA with a frequency of 140 Hz. The measurement was performed in the white matter within and outside peritumoral edema as well as in non-enhancing, enhancing and necrotic tumor areas. Resistivity values expressed in ohmmeter (Ω1m) were compared between different intracranial tissues and brain tumors.ResultsNinety-two patients (gliomas WHO II:16, WHO III:10, WHO IV:33, metastasis:33) were included. White matter outside peritumoral edema had higher resistivity values (13.3 ± 1.7 Ω1m) than within peritumoral edema (8.5 ± 1.6 Ω1m), and both had higher values than brain tumors including non-enhancing (WHO II:6.4 ± 1.3 Ω1m, WHO III:6.3 ± 0.9 Ω1m), enhancing (WHO IV:5 ± 1 Ω1m, metastasis:5.4 ± 1.3 Ω1m) and necrotic tumor areas (WHO IV:3.9 ± 1.1 Ω1m, metastasis:4.3 ± 1.3 Ω1m), p=<0.001. No difference was found between low-grade and anaplastic gliomas, p = 0.808, while resistivity values in both were higher than the highest values found in glioblastomas, p = 0.003 and p = 0.004, respectively.ConclusionsThe technique we applied enabled us to measure electrical resistivity of white matter and brain tumors in-vivo presumably with a significant effect with regard to dielectric polarization. Our results suggest that there are significant differences within different areas and subtypes of brain tumors and that white matter exhibits higher electrical resistivity than brain tumors. 相似文献
40.