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81.
Surgical approaches to correct corneal astigmatism at time of cataract surgery: a mini-review 下载免费PDF全文
Among refractive errors, astigmatism is the most common optical aberration, where refraction changes in different meridians of the eye. It causes blurred vision at any distance and includes corneal, lenticular, and retinal astigmatism. Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism, for example, a large size surgery incision. The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery. Nowadays, three surgical approaches can be used. By placing a sutureless clear corneal incision on the steep meridian of the cornea, a preoperative corneal astigmatism less than 1.0 D can be corrected. Single or paired peripheral corneal relaxing incisions (PCRIs) provide 1.0-3.0 D corneal astigmatism correction. PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism, if more than 2.0 D, the risk of overcorrection and irregular astigmatism is increased. When toric intraocular lenses (IOLs) are unavailable in markets, PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism. Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism. Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D. These approaches can be used alone or in combination. 相似文献
82.
Early changes in corneal densitometry after FS-LASIK combined with accelerated corneal cross-linking for correction of high myopia 下载免费PDF全文
AIM: To observe the effects of femtosecond laser-assisted excimer laser in situ keratomileusis combined with accelerated corneal cross-linking (FS-LASIK Xtra) on corneal densitometry after correcting for high myopia.
METHODS: In this prospectively study, 130 patients underwent FS-LASIK or FS-LASIK Xtra for high myopia. Their right eyes were selected for inclusion in the study, of which 65 cases of 65 eyes in the FS-LASIK group, 65 patients with 65 eyes in the FS-LASIK Xtra group. Patients were evaluated for corneal densitometry at 1, 3, and 6mo postoperatively using Pentacam Scheimpflug imaging.
RESULTS: Preoperative differences in corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups in different ranges were not statistically significant (P>0.05). Layer-by-layer analysis revealed statistically significant differences in the anterior (120 μm), central, and total layer corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups at 1 and 3mo postoperatively (all P<0.05), the FS-LASIK Xtra group is higher than that of the FS-LASIK group. Analysis of different diameter ranges showed statistically significant differences between the FS-LASIK group and the FS-LASIK Xtra group at 1mo postoperatively in the ranges of 0–2, 2–6, and 6–10 mm (both P<0.05); At 3mo postoperatively, the FS-LASIK Xtra group is higher than that of the FS-LASIK group in the ranges of 0–2 and 2–6 mm (P<0.05). At 6mo postoperatively, there were no statistically significant differences in corneal densitometry between the FS-LASIK group and the FS-LASIK Xtra group in different diameter ranges (all P>0.05).
CONCLUSION: There is an increase in internal corneal densitometry during the early postoperative period after FS-LASIK Xtra for correction of high myopia. However, the densitometry values decreased to the level of conventional FS-LASIK at 6mo after surgery, with the most significant changes observed in the superficial central zone. 相似文献
83.
目的研究肝前体细胞(hepatic progenitor cells,HPCs)、小管样反应、中间型肝细胞在慢性乙型肝炎组织中的分布特征和数量变化,以及与肝细胞再生之间的可能联系。方法对42例慢性乙型肝炎组织行常规病理HE染色,按炎症活动度(G)分为轻、中、重三度,免疫组织化学方法观察肝胆细胞标记(AFP、GST-π、CK7、CK19)和造血干细胞标记(c-kit、CD34)的表达,并以Ki-67标记增殖的肝细胞,用CK7/CK19作为标记物对符合定义的HPCs、中间型肝细胞进行计数,小管样反应程度的判定利用彩色病理图象分析系统。结果慢性乙型肝炎的早期阶段即存在HPCs的活化和小管样反应,其数量随着炎症活动度的增加而增加,均表达CK7、CK19、GST-π和AFP,肝细胞增殖指数在轻、中度肝炎中逐渐增加,重度肝炎、肝硬化患者增殖的肝细胞数下降,而中间型肝细胞数量显著增加。小管样反应面积百分比与HPCs数目正相关(r=0.739,P〈0.05),中间型肝细胞数目与HPCs数目正相关(r=0.614,P〈0.05)。结论慢性乙型肝炎中不仅有成熟肝细胞增殖,也存在肝前体细胞活化和分化,可能参与肝脏损伤后的再生修复。 相似文献
84.
Na Ri Choi Jeong Nam Kim Min Ji Kwon Jong Rok Lee Sang Chan Kim Min Jae Lee Woo-gyun Choi Byung Joo Kim 《International journal of medical sciences》2022,19(5):941
Grape seed is an important natural bioactive product with various health benefits. Interstitial cells of Cajal (ICCs) are pacemaker cells in the gastrointestinal (GI) tract. The present study investigated the effects of grape seed powder (GSP) on ICC properties and GI motility. GSP depolarized the pacemaker potentials of ICCs in a dose‑dependent manner. Y25130 or SB269970 slightly inhibited GSP‑induced effects. However, Y25130 and SB269970 together completely blocked GSP-induced effects. In the presence of inhibitors of protein kinase C, protein kinase A, or mitogen-activated protein kinase, GSP‑induced ICC depolarization was inhibited. GSP increased the intestinal transit rate in normal mice and in mice with acetic acid-induced GI motility disorder. In addition, the levels of motilin and substance P were elevated after GSP dosing. These results demonstrate that GSP can regulate GI motility, and therefore, it is a potential therapeutic agent for treating GI motility disorders. 相似文献
85.
Haixia Long Ming Fan Qiaojun Li Xuhua Yang Yujiao Huang Xinli Xu Ji Ma Jie Xiao Tianzi Jiang 《Human brain mapping》2022,43(9):2923
Aggression is a common and complex social behavior that is associated with violence and mental diseases. Although sex differences were observed in aggression, the neural mechanism for the effect of sex on aggression behaviors remains unclear, especially in specific subscales of aggression. In this study, we investigated the effects of sex on aggression subscales, gray matter volume (GMV), and functional connectivity (FC) of each insula subregion as well as the correlation of aggression subscales with GMV and FC. This study found that sex significantly influenced (a) physical aggression, anger, and hostility; (b) the GMV of all insula subregions; and (c) the FC of the dorsal agranular insula (dIa), dorsal dysgranular insula (dId), and ventral dysgranular and granular insula (vId_vIg). Additionally, mediation analysis revealed that the GMV of bilateral dIa mediates the association between sex and physical aggression, and left dId–left medial orbital superior frontal gyrus FC mediates the relationship between sex and anger. These findings revealed the neural mechanism underlying the sex differences in aggression subscales and the important role of the insula in aggression differences between males and females. This finding could potentially explain sexual dimorphism in neuropsychiatric disorders and improve dysregulated aggressive behavior. 相似文献
86.
高效毛细管电泳法同时测定尿液清蛋白和肌酐 总被引:1,自引:0,他引:1
目的建立同时测定尿液清蛋白和肌酐的高效毛细管电泳法。方法对缓冲系统、pH值、缓冲液的离子强度、检测波长、表面活性剂、电压及电流和进样方法等进行研究,建立同时测定清蛋白和肌酐的毛细管电泳法。结果选择20mmol/L、pH9.3硼砂-NaOH(含6mmol/LSDS)缓冲液作为毛细管区带电泳运行液,利用外标法定量,检测波长214nm,同时测定肌酐和清蛋白。非涂层毛细管有效长度47.5cm,内径75μm;电流79μA,压力进样1psi、4s,电泳时间为12min。肌酐和清蛋白的线性范围分别为4.32~8840μmol/L和1.95~1000mg/L,肌酐和清蛋白最低检出限分别为0.977μmol/L和0.285mg/L。本法的日内和日间变异系数均小于4.8%。肌酐和清蛋白的平均回收率分别为99.6%和102.4%。结论建立的方法线性范围宽,测定简单快速,可用于临床检测。 相似文献
87.
88.
目的:介绍气功对顽固性失眠的治疗措施。方法:从失眠的病因病机、周天功及六字诀治疗失眠的功理等入手详细分析了治疗的原理和原则。结果:将周天功与六字诀相配合可以有效地取长补短,达到心火下降,肾水上滋,心肾相交的效果。结论:气功对于顽固性失眠具有良好的治疗效果。 相似文献
89.
Saier Wang Ying Shi Huiming Xiang Ru Liu Lianghu Su Longjiang Zhang Rongting Ji 《RSC advances》2022,12(35):22760
Biochar has attracted great interest in both CO2 capture and supercapacitor applications due to its unique physicochemical properties and low cost. Fabrication of eco-friendly and cost-effective biochar from high potential biomass Tenebrio molitor feces can not only realize the functional application of waste, but also a potential way of future carbon capture and energy storage technology. In this study, a novel KOH activation waste-fed Tenebrio molitor feces biochar (TMFB) was developed and investigated in terms of CO2 capture and electrochemical performance. When activated at 700 °C for 1 h, the specific surface area of the feces biochar (TMFB-700A) increased significantly from 232.1 to 2081.8 m2 g−1. In addition, well-developed pore distribution facilitates CO2 capture and electrolyte diffusion. TMFB-700A can quickly adsorb a large amount of CO2 (3.05 mol kg−1) with excellent recycling performance. TMFB-700A also exhibited promising electrochemical performance (335.8 F g−1 at 0.5 A g−1) and was used as electrode material in a symmetrical supercapacitor. It provided a high energy density of 33.97 W h kg−1 at a power density of 0.25 kW kg−1 with 90.47% capacitance retention after 10 000 charge–discharge cycles. All the results demonstrated that TMFB could be a potential bifunctional material and provided valuable new insights for Tenebrio molitor feces high-value utilization.Biochar has attracted great interest in both CO2 capture and supercapacitor applications due to its unique physicochemical properties and low cost. 相似文献
90.
Four new 3-methyl-4-ethylideneproline-containing peptides, lucentamycins A-D (1-4), have been isolated from the fermentation broth of a marine-derived actinomycete identified by phylogenetic methods as Nocardiopsis lucentensis (strain CNR-712). The planar structures of the new compounds were assigned on the basis of 1D and 2D NMR spectroscopic techniques, while the absolute configurations of the amino acid residues were determined by application of the advanced Marfey method. Lucentamycins A (1) and B (2) showed significant in vitro cytotoxicity against HCT-116 human colon carcinoma. 相似文献