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51.
Shaohua Pi Tristan T. Hormel Bingjie Wang Steven T. Bailey Thomas S. Hwang David Huang John C. Morrison Yali Jia 《Biomedical optics express》2022,13(9):4889
Optical coherence tomography (OCT) is widely used in ophthalmic practice because it can visualize retinal structure and vasculature in vivo and 3-dimensionally (3D). Even though OCT procedures yield data volumes, clinicians typically interpret the 3D images using two-dimensional (2D) data subsets, such as cross-sectional scans or en face projections. Since a single OCT volume can contain hundreds of cross-sections (each of which must be processed with retinal layer segmentation to produce en face images), a thorough manual analysis of the complete OCT volume can be prohibitively time-consuming. Furthermore, 2D reductions of the full OCT volume may obscure relationships between disease progression and the (volumetric) location of pathology within the retina and can be prone to mis-segmentation artifacts. In this work, we propose a novel framework that can detect several retinal pathologies in three dimensions using structural and angiographic OCT. Our framework operates by detecting deviations in reflectance, angiography, and simulated perfusion from a percent depth normalized standard retina created by merging and averaging scans from healthy subjects. We show that these deviations from the standard retina can highlight multiple key features, while the depth normalization obviates the need to segment several retinal layers. We also construct a composite pathology index that measures average deviation from the standard retina in several categories (hypo- and hyper-reflectance, nonperfusion, presence of choroidal neovascularization, and thickness change) and show that this index correlates with DR severity. Requiring minimal retinal layer segmentation and being fully automated, this 3D framework has a strong potential to be integrated into commercial OCT systems and to benefit ophthalmology research and clinical care. 相似文献
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53.
博落回中生物碱质谱裂解规律研究进展 总被引:5,自引:1,他引:5
博落回中生物碱的代谢途径可简化为:氨基酸→苄基异喹啉类生物碱→四氢原小檗碱型生物碱(或者转化成阿朴芬类生物碱)→N-甲基-四氢原小檗碱型生物碱(或者转化成原小檗碱型生物碱)→普罗托品类生物碱→二氢苯并菲啶类生物碱→苯并菲啶类生物碱→苯并菲啶类生物碱二聚体。对博落回代谢途径中9类生物碱质谱裂解规律的总结,为利用质谱裂解方式初步确定生物碱的结构类型;利用LC-MS鉴定不同产地、不同时期、不同部位博落回中标识性生物碱;以博落回中生物碱为原料而开发的中兽药药动学以及药物残留的研究;解析博落回中微量生物碱的结构式以及对其他天然药物中同类生物碱的质谱研究提供参考。 相似文献
54.
P Acien A Milla F Segarra J L Pi?ero 《International journal of gynaecology and obstetrics》1987,25(4):323-329
A case of advanced secondary abdominal pregnancy is presented. It happened in a multiparous patient, a heroin addict and with a previous secondary amenorrhea. In spite of having been controlled through the whole pregnancy, the ectopic pregnancy was not diagnosed until a laparotomy was performed, several days after fetal death. After full extraction of the fetus and placenta, followed by left adnexectomy, the postoperatory evolution was normal. Hormonal and echographic studies and fetal monitorings are provided, and the diagnosis and treatment are discussed. 相似文献
55.
This study was to appraise the anti-inflammatory and free radical scavenging activities of ethanol extracts of Ilex ficoidea Hemsl (EIFH) and Ilex centrochinensis S.Y. Hu (EICC). Anti-inflammatory activities were evaluated using xylene-induced ear edema and the cotton pellet granuloma tests. Some antioxidants produced during chronic inflammation were quantitated and the DPPH, superoxide anion and hydroxyl free radicals scavenging activities in vitro were also investigated. EICC showed a significant anti-inflammatory effect during the acute inflammation and chronic inflammation without any acute oral toxicity. However, EIFH exhibited a negligible anti-acute inflammatory and a moderate anti-chronic inflammatory activity. EICC significantly inhibited the formation of MDA and markedly raised the activities of SOD, CAT and GSH-Px. EIFH could reduce the level of MDA and elevate the activity of SOD only at the high dose. The free radical scavenging activities of EICC are higher than that of EIFH. These results suggest that EICC possesses significant anti-inflammatory and free radical scavenging activities. The anti-inflammatory mechanism is attributed, in part, to enhance the activities of antioxidant enzymes. 相似文献
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57.
Monika Maria Biernat Jolanta Rusiecka-Ziółkowska Elżbieta Piątkowska Iwona Helemejko Paweł Biernat Grażyna Gościniak 《Japanese journal of ophthalmology》2018,62(6):628-633
Purpose
Two Demodex species (eyelash mites)—D. folliculorum and D brevis—are believed to be associated with human skin and eye diseases. However, the clinical significance of infection with Demodex species remains controversial.Study design
The aim of this study was to estimate the prevalence of ocular demodicosis in patients with blepharitis as compared with the prevalence in the healthy population in Poland.Methods
This case-control prospective study was carried out from 2007 to 2016. The enrolled patients (668) were divided into 2 groups: the study group, comprising 553 patients with blepharitis (349 women and 204 men, aged 17–88 years), and the control group, comprising 115 healthy volunteers without a history of ocular pathologies (78 women and 37 men, aged 17–88 years). A sample of 10 eyelashes was taken aseptically from each eye of the examined person and later studied under a light microscope.Results
Demodex species were found in 62.4% (345/544) of the patients in the study group and in 24.3% (28/100) of the controls (P = .001, OR = 0.006). The overall prevalence was 55.8% (373/668) in all the examined participants. The presence of Demodex infection increased with age in both groups. No association of Demodex infection with gender was found (119/204 vs 226/349; P > .05, OR 1.086). A high mean number of mites was present more frequently in patients aged older than 50 years and in those who complained especially about itching (P < .05).Conclusion
The prevalence of ocular demodicosis is significantly correlated with blepharitis and increases with age.58.
There is no mention in the literature of any analytical method to quantify toxins present in fruits of Karwinskia humboldtiana. It is recommended that thin layer chromatography and densitometry in situ be used, since it is rapid, sensitive and specific. Great variations in the toxin content of fruits collected in different regions of the state of Nuevo Leon (Mexico) were found, showing the importance of applying an analytical method before beginning toxicological experiments. 相似文献
59.
目的:探讨乳酸杆菌对新生鼠和成年鼠辅助性T细胞(Th)1/Th2平衡及肺树突状细胞表型(DC)的影响。方法:新生鼠从出生后连续7 d每天经口给予109 CFU/mL浓度乳酸杆菌10 μL,成年鼠选取满6周的小鼠连续7 d每天经口给予109 CFU/mL浓度乳酸杆菌50 μL,实验第8天进行盲肠内容物培养以确定乳酸杆菌肠道定植情况。干预3周后,采用酶联免疫吸附试验(ELISA)检测血清干扰素(IFN)-γ、白细胞介素(IL)-4和IL-10,流式细胞仪检测肺树突状细胞亚型和成熟度。结果:(1)乳酸杆菌干预的新生鼠乳酸杆菌数量较对照组增加,而肠球菌和肠杆菌数量降低(P<0.01),乳酸杆菌干预的成年鼠肠道乳酸杆菌数量明显增加(P<0.01),但肠道肠球菌和肠杆菌数量没有变化。(2)乳酸杆菌干预的新生鼠IFN-γ和IL-10水平较对照组高(P<0.05),IL-4水平两组比较差异无统计学意义。乳酸杆菌干预的成年鼠IFN-γ、IL-4和IL-10水平与对照组比较差异无统计学意义。(3)乳酸杆菌干预的新生鼠肺CD11c+CD8α-水平为92.34%±0.94%,较对照组降低(P<0.05);同时干预组CD11c+CD8α+水平较对照组增加(P<0.05)。经过乳酸杆菌干预后,新生鼠肺部14.03%±1.14%的DC表达MHCⅡ类分子,较对照组明显增加。成年鼠乳酸杆菌干预组CD11c+CD8α-、CD11c+CD8α+和CD11c+MHCⅡ+水平与对照组比较差异无统计学意义(P>0.05)。结论:乳酸杆菌干预可以促进新生鼠Th1/Th2平衡向Th1方向偏移,而对成年鼠没有影响。 相似文献
60.
目的 :用 HPL C法测定心元胶囊中大黄素与丹参酮 A 的含量。方法 :样品的甲醇提取物经酸水解用乙醚提取后 ,以 ODS柱分析 ,大黄素的测定 ,流动相为甲醇 -水 -磷酸 (80∶ 2 0∶ 0 .0 5 ) ,检测波长为 2 86 nm;丹参酮 A的测定 ,流动相为甲醇 -水 (80∶ 2 0 ) ,检测波长为 2 6 8nm。结果 :大黄素的线性范围为 0 .0 2 13~ 0 .2 13μg(r=0 .9999) ,样品加样回收率为 99.85 % ,RSD为 1.95 % (n=6 ) ;丹参酮 A 的线性范围为 0 .0 12~ 0 .0 5 9μg(r=0 .9993) ,样品加样回收率为 97.3% ,RSD为 1.3% (n=6 )。结论 :该法可供该制剂含量测定 相似文献