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994.
李黄恩 王勇 陈茂盛 李雪婷 徐艳雪 唐琼燕 周衍文 武哲明 司马晶 巫雷 曾庆森 曹向荣 高岩 党秀红 邱志方 李莉 李志强 单明华 祖皮丽娅 徐惠芳 李海祥 《中华眼科杂志》2021,(1):56-62
目的分析中国18家医院的14万例年龄相关性白内障患者角膜前表面散光的分布特征。方法回顾性系列病例研究。连续性收集2015年7月至2018年10月于中国18家爱尔眼科医院就诊的40岁以上年龄相关性白内障患者143889例(143889只右眼)的眼部生物学参数资料。角膜前表面散光度数和轴向、前房深度、角膜屈光力、眼轴长度等眼球参数采用IOLMaster 500测量,获取3次测量结果的平均值。各医院将资料整理分析后提交给武汉爱尔眼科医院进行总体分析。非正态分布数据以M(P25~P75)表示;采用Mann-Whitney检验、Kruskal-Wallis检验、χ2检验等分析角膜前表面散光度数和轴向在不同性别、年龄、前房深度、角膜屈光力、眼轴长度中的分布差异。结果143889例患者中女性84319例,男性59570例;年龄为72(65~78)岁;角膜散光度数为0.84(0.51~1.33)D,散光度数≥0.75 D者80895例(56.22%),散光度数≥1.00 D者57304例(39.83%)。女性角膜散光度数为0.87(0.53~1.37)D,男性为0.82(0.50~1.29)D(U=-14.891);女性顺规散光比例为33.26%(28046/84319),逆规散光比例为49.08%(41385/84319);男性顺规散光比例为34.26%(20408/59570),逆规散光比例为46.91%(27945/59570)(χ2=70.913),差异均有统计学意义(均P<0.05)。随年龄增加,角膜散光度数先由0.94(0.57~1.48)D减少至0.75(0.46~1.18)D,后又增大至1.19(0.74~1.79)D,差异有统计学意义(H=1263.438,P<0.05),变化的转折在61~70岁。随着年龄的增大,顺规散光比例减小[由77.50%(396/511)减少至12.50%(3/24)],逆规散光比例增大[由11.15%(57/511)增大至79.07%(34/43)],斜向散光比例变化不大[17.02%(16/94)至19.92%(245/1230)],分布差异有统计学意义(χ2=10174.496,P<0.05)。前房越浅,角膜散光度数越大,由0.82(0.51~1.31)D增大至1.05(0.61~1.56)D;逆规散光比例越大,由47.32%(60207/127227)增大至51.69%(184/356),差异均有统计学意义(H=409.961,χ2=120.995;均P<0.05)。平均角膜屈光力越大,角膜散光度数越大,由0.80(0.49~1.33)D增大至0.95(0.58~1.53)D;逆规散光比例越小,由52.84%(4963/9392)减小至39.97%(9023/22577),差异均有统计学意义(H=808.562,χ2=752.147;均P<0.05)。不同眼轴长度相比,当眼轴长度>25.00 mm时,角膜散光度数最大,为1.04(0.62~1.65)D;逆规散光比例最大,为49.00%(10964/22376),差异均有统计学意义(H=2071.198,χ2=131.130;均P<0.05)。结论年龄相关性白内障患者角膜前表面散光轴向以逆规散光为主。随着年龄的增大,角膜散光度数有先减小后增加的趋势。65岁为顺规散光向逆规散光变化的转折点。前房越浅,角膜前表面散光度数以及逆规散光比例越大。当眼轴长度>25.00 mm时,角膜前表面散光度数和逆规散光比例最大。 相似文献
995.
Arroyo Jorge G. Seto Brendan Yamada Keiko Zeng Ke Minturn Robert Lemire Colin A. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2021,259(8):2113-2118
Graefe's Archive for Clinical and Experimental Ophthalmology - We investigated the effects of a relatively inexpensive, non-invasive, short-term treatment with low-dose normobaric hyperoxia... 相似文献
996.
Qianqian Yan Huanjun Xu Xuechao Jing Hui Hu Shenglin Wang Chaoyuan Zeng Yanan Gao 《RSC advances》2020,10(30):17396
Post-synthetic modification has been the most powerful strategy for covalent organic frameworks (COFs) for their functionalization in many fields. This strategy is typically achieved through the quantitative reaction between existing reactive sites on the linkers (building units) and incoming functional groups. However, usage of linkages (bonds formed to construct COFs) for the post-synthetic modification still remains limited. Herein, we develop a new post-synthetic modification route that is based on the modification of linkages. With this strategy, the imine linkages of a two-dimensional (2D) COF, TFPPy–PyTTA–COF, have been transformed into amine linkages to give the amine-linked isostructure with retention of crystallinity and porosity. The subsequent aminolysis of the amine linkages with 1,3-propane sultone and further metathetical reaction with cobalt acetate [Co(OAc)2] enable the introduction of cobalt alkyl sulfonate to the one-dimensional (1D) channel walls of the COF. The resulting ionic COF with coupled Co2+ in the frameworks shows excellent catalytic activity and good recyclability towards the cycloaddition reactions of epoxides and CO2. This strategy is of interest as it opens a way to use linkage modification for exploring the potential of COFs for different applications.A new approach for post-synthetic modification of covalent organic frameworks has been developed based on the modification of the linkages and the resulting COF exhibited excellent catalytic performance towards cycloaddition of epoxides and CO2. 相似文献
997.
Chen Song Xin Gao Wei Song Deyong Zeng Shan Shan Yishu Yin Yongzhi Li Denis Baranenko Weihong Lu 《RSC advances》2020,10(27):16196
Complex space environments, including microgravity and radiation, affect the body''s central nervous system, endocrine system, circulatory system, and reproductive system. Radiation-induced aberration in the neuronal integrity and cognitive functions are particularly well known. Moreover, ionizing radiation is a likely contributor to alterations in the microbiome. However, there is a lacuna between radiation-induced memory impairment and gut microbiota. The present study was aimed at investigating the effects of simulated space-type radiation on learning and memory ability and gut microbiota in mice. Adult mice were irradiated by 60Co-γ rays at 4 Gy to simulate spatial radiation; behavioral experiments, pathological experiments, and transmission electron microscopy all showed that radiation impaired learning and memory ability and hippocampal neurons in mice, which was similar to the cognitive impairment in neurodegenerative diseases. In addition, we observed that radiation destroyed the colonic structure of mice, decreased the expression of tight junction proteins, and increased inflammation levels, which might lead to dysregulation of the intestinal microbiota. We found a correlation between the brain and colon in the changes in neurotransmitters associated with learning and memory. The 16S rRNA results showed that the bacteria associated with these neurotransmitters were also changed at the genus level and were significantly correlated. These results indicate that radiation-induced memory and cognitive impairment can be linked to gut microbiota through neurotransmitters.Exposure to 60Co-γ ray impacts learning and memory ability as well as the cell morphology and neurotransmitters in hippocampus, even disrupts the bacterial community in colon. 相似文献
998.
Guolin Cao Jie Zhu Yunjiao Li Yuan Zhou Zhuomin Jin Bin Xu Chunxi Hai Jinbo Zeng 《RSC advances》2020,10(17):9917
Nickel–Cobalt–Aluminum (NCA) cathode materials for lithium-ion batteries (LIBs) are conventionally synthesized by chemical co-precipitation. However, the co-precipitation of Ni2+, Co2+, and Al3+ is difficult to control because the three ions have different solubility product constants. This study proposes a new synthetic route of NCA, which allows fabrication of fine and well-constructed NCA cathode materials by a high temperature solid-state reaction assisted by a fast solvothermal process. The capacity of the LiNi0.88Co0.09Al0.03O2 as-synthesized by the solvothermal method was 154.6 mA h g−1 at 55 °C after 100 cycles, corresponding to 75.93% retention. In comparison, NCA prepared by the co-precipitation method delivered only 130.3 mA h g−1 after 100 cycles, with a retention of 63.31%. Therefore, the fast solvothermal process-assisted high temperature solid-state method is a promising candidate for synthesizing high-performance NCA cathode materials.Nickel–Cobalt–Aluminum (NCA) cathode materials for lithium-ion batteries (LIBs) are conventionally synthesized by chemical co-precipitation. 相似文献
999.
目的 探讨妊娠期急性胰腺炎的病因及临床诊治经验.方法 回顾性分析15例妊娠合并急性胰腺炎的发病特点、治疗方法及结局.结果 15例产妇均治愈,无严重并发症发生,孕妇无流产及死亡.终止妊娠5例,其中2例妊娠合并轻症急性胰腺炎者1例实施了引产,1例行剖宫产术;3例妊娠合并重症急性胰腺炎患者实施了剖宫产.结论 对于妊娠合并轻症胰腺炎患者尽量选择保守治疗,病情加重时,可以终止妊娠;对于妊娠合并重症急性胰腺炎患者,若病情能够控制,且胎儿宫内情况良好,可尽量延长孕周至32~34周,若孕妇病情加重或无缓解则应尽早终止妊娠. 相似文献
1000.
目的 探讨正性激励在静脉药物配置中心(PIVAS)护理工作中的应用效果.方法 将正性激励机制应用于PIVAS护理工作,体现于管理制度、工作过程、学习培训等各个阶段.结果 工作效率得到进一步提升,2012年与2011年护理人员单日工作指标比较,每日药品配置时间缩短30.27min;2012年与2011年差错发生率、临床科室满意度、每季度PIVAS护理人员职业认同感比较,差异有统计学意义(均P<0.01).结论 正性激励应用于PIVAS的护理管理,可提高工作效率,增强团队意识,科室形象得到更好的塑造,与临床科室的关系也更为融洽. 相似文献