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991.
Yusuf Osmanlolu Drew Parker Jacob A. Alappatt James J. Gugger Ramon R. DiazArrastia John Whyte Junghoon J. Kim Ragini Verma 《Human brain mapping》2022,43(13):3944
Traumatic brain injury (TBI) is a major public health problem. Caused by external mechanical forces, a major characteristic of TBI is the shearing of axons across the white matter, which causes structural connectivity disruptions between brain regions. This diffuse injury leads to cognitive deficits, frequently requiring rehabilitation. Heterogeneity is another characteristic of TBI as severity and cognitive sequelae of the disease have a wide variation across patients, posing a big challenge for treatment. Thus, measures assessing network‐wide structural connectivity disruptions in TBI are necessary to quantify injury burden of individuals, which would help in achieving personalized treatment, patient monitoring, and rehabilitation planning. Despite TBI being a disconnectivity syndrome, connectomic assessment of structural disconnectivity has been relatively limited. In this study, we propose a novel connectomic measure that we call network normality score (NNS) to capture the integrity of structural connectivity in TBI patients by leveraging two major characteristics of the disease: diffuseness of axonal injury and heterogeneity of the disease. Over a longitudinal cohort of moderate‐to‐severe TBI patients, we demonstrate that structural network topology of patients is more heterogeneous and significantly different than that of healthy controls at 3 months postinjury, where dissimilarity further increases up to 12 months. We also show that NNS captures injury burden as quantified by posttraumatic amnesia and that alterations in the structural brain network is not related to cognitive recovery. Finally, we compare NNS to major graph theory measures used in TBI literature and demonstrate the superiority of NNS in characterizing the disease. 相似文献
992.
C型钠尿肽抑制大鼠胃窦环行肌自发性收缩活动 总被引:3,自引:0,他引:3
Guo HS Cui X Cui YG Kim SZ Cho KW Li ZL Xu WX 《Acta pharmacologica Sinica》2003,24(10):1021-1026,1062
目的:研究钠尿肽对胃动力的作用及其可能的机制.方法:用四道记录仪记录胃窦环行肌条的自发性收缩活动;利用放射免疫技术测定cGMP的产生量;利用放射自显影技术分析钠尿肽受体在胃内的分布情况.结果:钠尿肽受体在大鼠胃的不同部位均有分布,但在胃窦部最多。ANP、BNP和CNP均能抑制胃窦环行肌条的自发性收缩,其中,CNP的作用尤为明显并呈剂量依赖关系.CNP的这种抑制性作用被鸟苷酸环化酶抑制剂LY83583所削弱,而用cGMF敏感的磷酸酯酶抑制剂zaparinist预处理时CNP的抑制作用明显增加.CNP明显提高胃窦环行肌cGMP的浓度.用非选择性钾通道阻断剂TEA预处理后发现CNP对胃窦环行肌自发性收缩活动的抑制作用明显减弱.结论:钠尿肽受体在大鼠的胃窦分布最多.CNP明显抑制大鼠胃窦环行肌的自发性收缩活动.CNP对大鼠胃窦环行肌自发性收缩活动的抑制效应是通过cGMP途径实现的.钾通道也参与CNP对大鼠胃窦平滑肌的舒张过程。 相似文献
993.
Meijie Tian Adam T. Cheuk Jun S. Wei Abdalla Abdelmaksoud Hsien-Chao Chou David Milewski Michael C. Kelly Young K. Song Christopher M. Dower Nan Li Haiying Qin Yong Yean Kim Jerry T. Wu Xinyu Wen Mehdi Benzaoui Katherine E. Masih Xiaolin Wu Zhongmei Zhang Sherif Badr Naomi Taylor Brad St. Croix Mitchell Ho Javed Khan 《The Journal of clinical investigation》2022,132(16)
994.
To enhance the formability of magnesium alloys, inhibition of basal texture development by the particle-stimulated nucleation (PSN) effect has attracted significant interest. However, its contribution to texture development is not easily observed due to the separation of texture from the conventional deformation behavior. This study aims to separate the Ca texture from the deformation behavior of AZX611 alloy and quantify it using scanning electron microscopy with electron backscatter diffraction (SEM-EBSD). Since Ca in the AZ61 magnesium alloy precipitated as Al2Ca, the hot-rolled magnesium alloys AZ31, AZ61, and AZX611 were used. High temperature compression was conducted at 723 K, the strain rate 0.05/s and 0.005/s and the true strain up to −1.0. Dynamic recrystallization was observed in each specimen and the Ca-free alloys showed dislocation glide at high strain rates and solute drag at low strain rates. When the dislocation glide dominated, basal texture was strengthened. In contrast, solute drag caused non-basal texture development. Precipitation hardening caused AZ61 to have higher flow stress than those of the Ca-free alloys by the PSN effect; its texture was observed separately because the PSN grain growth around the precipitation and orientation was specific, similar to the one developed at the solute atom drag. 相似文献
995.
Yeon Soo Kim Jae Won Choi Ju-Kyeong Park Hyun Jung Kim 《Acta oto-laryngologica》2015,135(12):1311-1318
Conclusion: The results of the present investigation suggest that modification of HA could improve efficiency and durability in augmentation laryngoplasty. Objectives: Injection laryngoplasty (IL) is one of the most suitable options for treatment of glottic insufficiency, which is caused by vocal fold (VF) paralysis, atrophy, or scarring. Hyaluronic acid (HA) is a widely used material for VF injection. This study was intended to evaluate the durability and efficiency of HA of different particle sizes for VF augmentation. Methods: Three types of HA, Restylane®, monophasic low-viscosity, and unequal particle-sized middle-viscosity HA were injected into the left VF of three groups with eight rabbits each. Results: After 6 and 10 weeks, the injected site was evaluated endoscopically, histologically, radiologically, and functionally. None of the 24 rabbits showed any signs of respiratory distress. Computed tomography (CT) images and endoscopic evaluation revealed sufficient augmented volume of the injected VF in all treated groups 6 weeks after the injection. Histological data at week 10 showed that unequal particle-sized HA did not migrate from its original injection site, while other HAs migrated to the periphery of the arytenoid cartilage. Videokymographic analysis showed more favorable vibrations of unequal particle-sized HA injected VF mucosa 10 weeks post-injection, compared to the other treatment groups. 相似文献
996.
A previous animal study demonstrated that the administration of Omija extract and soybean mixture (OSM) improved glycemic control in the type 2 diabetes model. In this study, we conducted a 12-week, randomized, double-blinded, and placebo-controlled clinical trial to determine the effects of OSM in humans with hyperglycemia. Participants with fasting plasma concentrations of 100–140 mg/dL were enrolled (n = 80) and administered either OSM or placebo products for 12 weeks. The outcomes included measurements of efficacy (fasting plasma glucose (FPG), postprandial glucose (PPG), fasting plasma insulin (FPI), postprandial insulin (PPI), hemoglobin A1c (HbA1c), C-peptide, fructosamine, and lipid parameters) and safety at baseline and at 12 weeks. After the intervention, the OSM group showed significantly decreased levels of FPG, PPG (30, 60 min), PPI (60 min), insulin area under the curve (AUC), fructosamine, and low-density-lipoprotein (LDL) cholesterol compared to the placebo group. No clinically significant changes in any safety parameter were observed. Therefore, it is hypothesized that OSM supplementation is an effective and safe functional food supplement for humans with hyperglycemia. 相似文献
997.
998.
999.
Pulmonary atresia with intact ventricular septum (PAIVS) is a rare congenital cardiac anomaly that has been classified into
two types: one is a more frequent type having dysplasia of tricuspid valve (TV) with a small annulus, underdeveloped right
ventricle (RV) with a hypoplastic cavity and a hypertrophic wall; the other type has severe dysplasia of TV and dilatation
of RV, right atrium (RA), and right atrioventricular junction with thinning of the RV wall.
We performed a morphologic study on 11 autopsied hearts with PAIVS, giving particular emphasis to the variation of morphology
of the TV. We could classify these hearts into 3 groups according to the degree of right ventricular development. In the first
group of 7 cases (type I), the RVs were underdeveloped. Thick leaflets, restricted valve apparatus with short chordae, and
small annuli were characteristics of the TV. In the second group of 3 cases (type II), the RVs showed marked enlargement of
the cavity and thinning of the wall. The TV showed redundant, dysplastic, sail-like anterior leaflets, and the downward displacement
of septal leaflet and/or posterior leaflet, which are the findings frequently observed in Ebstein's malformation. The RVs
were dilated and with partially unguarded tricuspid orifice. The septal leaflet of the TV was dysplastic and, in two cases,
the septal leaflet showed chordal structure at the upper surface facing the RA, which is a peculiar finding that has not been
described in the literature. The remaining case was a heart with a moderately developed RV (type III). The TV showed mildly
dysplastic appearance and we classify this as a separate type, because we could expect the best surgical results in this type.
This type had optimal size of RV and the mildest degree of dysplasia of TV. In PAIVS, the morphology of TV correlates well
with the type of the right ventricular development. 相似文献
1000.
Jeong Min Yang Su bin Lee Ye ji Kim Douk young Chon Jong Youn Moon Jae Hyun Kim 《Medicine》2022,101(32)
This empirical study identifies the negative aspects of private health insurance (PHI) by analyzing the association between subjective health conditions, 2 weeks of outpatient care, chronic diseases, and hospitalizations for 1 year. We used frequency analysis, χ2 testing, an analysis of variance, and logistic and multiple logistic regression models to analyze the association between PHI and subjective health conditions, outpatient care, chronic disease status, and hospitalization. The PHI group had good subjective health but had more outpatient care for 2 weeks. There were few chronic diseases in the private insurance group, and there was no significant difference in hospitalizations for 1 year. Hospitalization may occur when essential medical care is required, regardless of health insurance type. This study confirmed that as the PHI lowers the burden of personal medical expenses, the PHI can lead to an increase in the medical resource expenditures on the outpatient medical service and higher public health costs. The government should work to redefine the role of private and national health insurance. Also, the effectiveness of PHI should be reevaluated so that it does not lead to indiscriminate use of medical services by minimizing the burden of private insurance. 相似文献