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221.
Shishir Verghese Sean T Berkowitz Virna M Shah Parag Shah S Priya Veerappan R Saravanan Venkatapathy Narendran V A Selvan 《Indian journal of ophthalmology》2022,70(2):448
Purpose:To assess the retinal manifestations of Parkinson’s disease using optical coherence tomography.Methods:A prospective case-control study comparing 30 eyes from 15 patients with Parkinson’s disease and 22 eyes from 11 healthy age-matched controls. Total macular subfield thickness and the thickness of the ganglion cell layer, nerve fiber layer, and peripapillary retinal nerve fiber layer were measured with spectral-domain optical coherence tomography (SD-OCT).Results:The mean age of PD patients was 68.4 years ± 10.64 (range: 46–82) and in the control group was 66.36 ± 5.22 (range: 64–68). The average disease duration in patients with PD was 6.7 ± 2.8 years (range: 2–10 years). The mean best-corrected visual acuity in PD was 20/26 and 20/20 in controls, with P = 0.0059, which was significant. Significant difference was also found in the contrast sensitivity between both groups. Structural differences in the central macular thickness (P = 0.0001), subfield thicknesses in the superior (P = 0.003), inferior (P = 0.001), nasal (P = 0.004), and temporal subfields (P = 0.017) was seen. Severe thinning of the ganglion cell layer was seen in PD patients (P = 0.000) as well as of the nerve fiber layer (P = 0.004). Peripapillary retinal nerve fiber thickness measured showed significant thinning in superotemporal (P = 0.000), superonasal (P = 0.04), inferonasal (P = 0.000), inferotemporal (P = 0.000), nasal (P = 0.000), and temporal quadrants (P = 0.000).Conclusion:Visual dysfunction was observed in patients with PD along with structural alterations on OCT, which included macular volumes, ganglion cell layer, and peripapillary retinal nerve fiber layer. 相似文献
222.
Purpose:To evaluate peripapillary-RNFL thickness in myopia by Cirrus OCT among north Indian population by spherical equivalent (SE), age, gender, and axial length (AL).Methods:This was a cross-sectional study held during 2019–2020. Patients aged 18–60 years underwent ophthalmic examination including retinoscopy, AL, and OCT RNFL thickness. Persons with previous ocular surgery or ocular ailment other than refractive error were excluded. The peripapillary-RNFL thickness was noted and compared by demographic determinants.Results:We examined 300 eyes of 300 persons (mean age: 30.75 ± 8.57 years; 144 males/156 females). Among them, 224 were myopes and 76 were emmetropes (EM). The mean SE was − 3.3 ± 0.4D (range: −11.0D to + 0.37D). The mean AL was 24.61 ± 1.92 mm (22.1–29.5). Overall temporal, nasal, superior, inferior, and mean peripapillary-RNFL thickness was 66.31 ± 7.58, 78.57 ± 16.00, 120.63 ± 11.69, 116.60 ± 15.80, and 95.50 ± 10.84 mm, respectively. Temporal, nasal, superior, inferior, and mean peripapillary-RNFL thickness was 73.97 ± 8.36, 94.84 ± 7.63, 127.96 ± 8.96, 136.89 ± 6.53, and 108.34 ± 6.28 mm, respectively, in EM eyes as compared to 63.71 ± 6.18, 73.05 ± 14.24, 118.21 ± 11.53, 109.71 ± 11.50, and 91.14 ± 8.31 mm, respectively, in myopic eyes (P < 0.001). Association of peripapillary-RNFL thickness with myopia and its different grades was P < 0.001. Association of mean peripapillary-RNFL thickness with age was P > 0.005 and gender was P = 0.168. Correlation between SE and RNFL thickness was positive and significant. Correlation between AL and RNFL thickness was negative but statistically significant. Association of AL with SE was P < 0.001.Conclusion:We provide normative peripapillary-RNFL thickness in the north Indian population in order to help in screening for myopia with comorbidity such as glaucoma based on RNFL thickness. 相似文献
223.
目的评价单皮层聚醚砜(PES)膜对肝细胞培养的支持作用,为其用于生物人工肝支持系统生物反应器的制备奠定基础。方法通过显微镜观察制备的平板膜结构,在PES膜上培养HepG2细胞,检测培养细胞的形态、生长曲线、白蛋白合成、戊醚试卤灵转化等功能。结果制备的PES膜为单皮层非对称性多孔结构;PES膜上HepG2细胞的生长曲线典型,在8天的培养时间能增殖6至7倍:细胞在PES膜上粘附呈多细胞聚集生长,部分细胞延伸入表面微孔内;PES膜上培养细胞LDH漏出量与对照无显著差异。PES膜上培养HepG2细胞具有较强的蛋白合成和生物转化功能。结论PEs平板膜能较好的支持肝细胞的粘附、生长、增殖和功能的表达,可用于中空纤维的制备。 相似文献
224.
目的探讨大鼠腹外斜肌的肌纤维型组成和分布,借以了解该肌功能,并为运动训练模型的建立提供理论依据和研究平台。方法采用Guth-Samaha肌球蛋白ATP酶组织化学染色法并稍做改良,对成年SD大鼠腹外斜肌冰冻切片进行肌纤维分型研究。结果SD大鼠腹外斜肌经肌球蛋白ATP酶组织化学染色后可明确分出2型肌纤维,即明亮色白的Ⅰ型纤维(慢缩纤维)和幽暗深褐的Ⅱ型纤维(快缩纤维),并且,2种纤维在肌内呈棋盘样均匀分布;图像分析仪下计数Ⅱ型纤维达到(84.8±5.3)%,而Ⅰ纤维仅占(15.2±2.1)%,前者占绝对优势(P<0.01)。结论SD大鼠腹外斜肌以Ⅱ型纤维为主,除了起保护腹腔脏器作用外,还参与力量和速度运动。 相似文献
225.
目的观察玻璃纤维桩用于残根残冠修复的临床效果。方法110例经过完善根管治疗的残根残冠患者,共136颗牙,随机分为两组,对照组与观察组各55例68颗牙。观察组用玻璃纤维桩修复,对照组用铸造金属桩,两组均用烤瓷冠恢复牙体外型,随访3年,观察疗效。结果对照组成功56例,失败12例,成功率82.35%;观察组成功65例,失败3例,成功率95.59%,两组比较差异有统计学意义(P〈0.05)。结论玻璃纤维桩应用于残根残冠修复的临床效果优于铸造金属桩。 相似文献
226.
Dongdong Lu Yu Pi Hao Ye Yujun Wu Yu Bai Shuai Lian Dandan Han Dongjiao Ni Xinhua Zou Jinbiao Zhao Shuai Zhang Bas Kemp Nicoline Soede Junjun Wang 《Nutrients》2022,14(12)
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers. 相似文献
227.
Polyurethane cement (PUC) is now commonly used in the reinforcement of old bridges, which exhibit various issues such as poor toughness, temperature-sensitive mechanical properties, and brittle failure. These problems can lead to the failure of the reinforcement effect of the PUC on old bridges in certain operating environments, leading to the collapse of such reinforced bridges. In order to alleviate these shortcomings, in this study, the toughness of PUC is improved by adding polyvinyl alcohol (PVA) fiber, carbon fiber, and steel fiber. In addition, we study the change law of the flexural strength of PUC between −40 °C and +40 °C. The control parameters evaluated are fiber type, fiber volume ratio, and temperature. A series of flexural tests and scanning electron microscope (SEM) test results show that the flexural strength first increases and then decreases with the increase in the volume-doping ratio of the three fibers. The optimum volume-mixing ratios of polyvinyl alcohol (PVA) fiber, carbon fiber, and steel fiber are 0.3%, 0.04% and 1%, respectively. Excessive addition of fiber will affect the operability and will adversely affect the mechanical properties. The flexural strength of both fiber-reinforced and control samples decreases with increasing temperature. Using the flexural test results, a two-factor (fiber content, temperature) BP neural network flexural strength prediction model is established. It is verified that the model is effective and accurate, and the experimental value and the predicted value are in good agreement. 相似文献
228.
目的 比较IPSe.max CAD高嵌体和纤维桩核冠对邻牙合面缺损上颌第一前磨牙修复后对抗折力的影响。方法 收集2021年9月至2023年7月在郑州大学第一附属医院因正畸而拔除的60颗上颌第一前磨牙,随机将其分为A、B、C 3组(n=20),A组、B组样本牙进行完善的根管治疗后,制备邻牙合面缺损洞型,分别采用不同的修复方法。A组行IPSe.max CAD高嵌体修复;B组行纤维桩核冠修复;C组为对照组,样本牙不作处理。记录各组折断力值、折断模式,并进行比较。结果 A组、B组和C组折裂载荷值分别为(781.25±61.23)N、(712.51±54.36)N和(420.28±41.28)N,3组间比较,差异有统计学意义(F=262.154,P<0.001),A组的折裂荷载值最高;3组折裂模式均以可修复折裂为主,组间比较差异无统计学意义(P>0.05)。结论 邻牙合面缺损上颌第一前磨牙采用IPSe.max CAD高嵌体修复后具有较好的临床效果,抗折力较高,且折裂模式主要为可修复性折裂。 相似文献
229.
目的 探索以脱细胞的肾纤维囊作为载体培养角膜基质细胞并研究培养角膜基质细胞特性。方法 将培养扩增的兔角膜基质细胞分别接种到培养板和肾纤维囊上进行体外培养,采用倒置显微镜、免疫组化(波形蛋白)和免疫荧光(AO、PI和Hoechst)的方法进行检测,观察兔角膜基质细胞在培养板和肾纤维囊上的生长情况。结果 倒置显微镜和免疫荧光显微镜观察结果显示角膜基质细胞在肾纤维囊上快速贴壁生长并增殖,细胞形态呈多角形树枝状,多次传代后细胞仍维持原有的形态和功能,细胞能长期培养。在培养板上培养的细胞呈长梭形,细胞贴壁生长和增殖情况稍差。在肾纤维囊上的活细胞较在培养板上培养的细胞多。结论 角膜基质细胞在脱细胞的肾纤维囊载体上生长良好,细胞形态结构明显。本研究为角膜基质细胞的体外培养,提供了简单和高效的方法。 相似文献
230.
A flexible hollow polypropylene (PP) fiber was filled with the phase change material (PCM) polyethylene glycol 1000 (PEG1000), using a micro-fluidic filling technology. The fiber’s latent heat storage and release, thermal reversibility, mechanical properties, and phase change behavior as a function of fiber drawing, were characterized. Differential scanning calorimetry (DSC) results showed that both enthalpies of melting and solidification of the PCM encased within the PP fiber were scarcely influenced by the constraint, compared to unconfined PEG1000. The maximum filling ratio of PEG1000 within the tubular PP filament was ~83 wt.%, and the encapsulation efficiencies and heat loss percentages were 96.7% and 7.65% for as-spun fibers and 93.7% and 1.53% for post-drawn fibers, respectively. Weak adherence of PEG on the inner surface of the PP fibers favored bubble formation and aggregating at the core–sheath interface, which led to different crystallization behavior of PEG1000 at the interface and in the PCM matrix. The thermal stability of PEG was unaffected by the PP encasing; only the decomposition temperature, corresponding to 50% weight loss of PEG1000 inside the PP fiber, was a little higher compared to that of pure PEG1000. Cycling heating and cooling tests proved the reversibility of latent heat release and storage properties, and the reliability of the PCM fiber. 相似文献