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991.
Samip Shrestha Jia Zhang Jun Yan Xiaomin Zeng Xiaoyong Peng Bo He 《Dento maxillo facial radiology》2021,50(5)
Objective:To review and analyze the clinical and imaging features of central giant cell granuloma patients and to review the relevant literatures for the diagnosis and clinical manifestation of central giant cell granuloma.Methods:Seven cases of central giant cell granuloma were retrospectively selected for the study, all of which were confirmed by pathology and had relevant imaging investigations. All seven cases had undergone CT scan, three cases had undergone MRI scan. Detailed clinical features were compared along with the imaging findings and analysis was done on the basis of their presentation and imaging features.Results:The clinical features, radiologic features were varied according to the site of the lesion. CT features include unevenly dense expansile mass causing bone destruction and cortical thinning. While MRI features with low to iso-intensity in T1- and T2 weighted images. There may be presence of cystic degeneration, hemorrhage or hemosiderin deposits or osteoid formation, which can cause T1 and T2 signal changes. On contrast study, the lesion doesn’t enhance but periphery may enhance mildly.Conclusion:Unevenly dense expansile mass with bone destruction and cortical thinning with low to iso-intensity in T1 weighted and T2 weighted images and mildly enhance peripherally, Central giant cell granuloma should be considered. 相似文献
992.
Jiao Li Yiqiong Liu Qin Li Xiaolin Huang Dingxi Zhou Hanjian Xu Feng Zhao Xiaoxiao Mi Ruoxu Wang Fan Jia Fuqiang Xu Jing Yang Dong Liu Xuliang Deng Yan Zhang 《神经科学通报》2021,37(3):311-322
Myoclonus dystonia syndrome(MDS)is an inherited movement disorder,and most MDS-related mutations have so far been found in theε-sarcoglycan(SGCE)coding gene.By generating SGCE-knockout(KO)and human 237 C>T mutation knock-in(KI)mice,we showed here that both KO and KI mice exerted typical movement defects similar to those of MDS patients.SGCE promoted filopodia development in vitro and inhibited excitatory synapse formation both in vivo and in vitro.Loss of function of SGCE leading to excessive excitatory synapses that may ultimately contribute to MDS pathology.Indeed,using a zebrafish MDS model,we found that among 1700 screened chemical compounds,Vigabatrin was the most potent in readily reversing MDS symptoms of mouse disease models.Our study strengthens the notion that mutations of SGCE lead to MDS and most likely,SGCE functions to brake synaptogenesis in the CNS. 相似文献
993.
Cao Zheng-Ye Wang Na Jia Jie-Ting Zhang Hong-Ying Shang Song-An Hu Jing-Jing Xu Yuan Wu Jing-Tao 《Brain imaging and behavior》2021,15(1):14-24
Brain Imaging and Behavior - Using resting-state functional magnetic resonance imaging and graph theory approaches to investigate the topological characteristics of functional networks and their... 相似文献
994.
995.
目的探讨甲状腺功能异常与不良孕产史发生的相关性以及孕前甲状腺功能筛查的意义。方法选取2011年10月-2012年10月在我院进行孕前检查的女性2031名,采用固相化学发光酶免疫分析法检测sTSH,对于sTSH在正常范围外的人群,检测FT4、FT3.结果甲状腺功能异常的发生率为9.85%,有不良孕产史女性的甲状腺功能异常所占比例明显高于正常妊娠组,差别有统计学意义;体重指数高的人群甲功异常的发生率高于体重指数低的人群。结论甲状腺功能异常与不良孕产史有明显相关性;进行孕前期甲状腺功能筛查很有必要。 相似文献
996.
目的 探讨超声清洗时间和消毒灭菌频率对镍钛根管锉的抗拉性能的影响,以了解超声清洗和高温高压消毒灭菌法在镍钛根管锉灭菌中应用的安全性和可行性.方法 采用全新的ProTaper S2锉和F2锉各25支,分为5组:标准组(未处理)、对照组(未超声-高压灭菌)、A组(超声震荡50 min+高压灭菌5次)、B组(超声震荡100 min+高压灭菌10次)、C组(超声震荡150 min+高压灭菌15次),分别用万能测试仪对其进行抗拉伸强度的性能试验.结果 S2及F2的标准组之间的抗拉伸强度差异无统计学意义(P>0.05),提示样本间不存在差异性;经不同时间超声清洗及不同次数高温高压处理的S2镍钛锉抗拉伸强度测试结果显示:对照组、A组、B组、C组分别为(76.58±4.87)MPa、(71.00±5.39)MPa、(72.33±3.43)MPa、(66.81±4.08)MPa;F2镍钛锉抗拉伸强度结果分别为:(111.75±6.83)MPa、(110.46±3.88)MPa、(107.29±3.89)MPa、(94.53±6.61)MPa;A、B组与对照组的ProTaper S2锉和F2锉的抗拉强度差异均无统计学意义(P>0.05),即镍钛锉经超声震荡50 min+高压灭菌5次及超声震荡100 min+高压灭菌10次消毒后,其抗拉伸强度无明显影响;C组与对照组间差异存在统计学意义(P<0.05),即镍钛锉经超声震荡150 min+高压灭菌15次消毒后,对其抗拉伸强度有影响.结论 常规超声-高压灭菌消毒超过一定频率可能增加ProTaper系统镍钛根管锉折断可能性. 相似文献
997.
998.
Bo Zhang Yan Zhou Nan Lin Rebecca F. Lowdon Chibo Hong Raman P. Nagarajan Jeffrey B. Cheng Daofeng Li Michael Stevens Hyung Joo Lee Xiaoyun Xing Jia Zhou Vasavi Sundaram GiNell Elliott Junchen Gu Taoping Shi Philippe Gascard Mahvash Sigaroudinia Thea D. Tlsty Theresa Kadlecek Arthur Weiss Henriette O’Geen Peggy J. Farnham Cécile L. Maire Keith L. Ligon Pamela A.F. Madden Angela Tam Richard Moore Martin Hirst Marco A. Marra Baoxue Zhang Joseph F. Costello Ting Wang 《Genome research》2013,23(9):1522-1540
999.
Ling Li Pengcheng Jia Wentao Bi Yang Tang Bo Song Liang Qin Zhidong Lou Yufeng Hu Feng Teng Yanbing Hou 《RSC advances》2020,10(47):28083
The ion migration in perovskite materials has been extensively studied by researchers, but the charge dynamic distribution caused by ion migration and carrier trapping is partly unclear. To investigate the impacts of ion migration and defect induced carrier trapping on the carrier transport and the carrier collection, we measured the evolution of the photocurrent response in microseconds, milliseconds and seconds for the perovskite solar cells pretreated at different biases. Our results reveal that the photocurrent of the solar cells pretreated at negative bias decreases with time and achieves its minimum at several milliseconds, then rises and achieves its maximum at tens of seconds. For the device pretreated at positive bias beyond built-in potential, the time to reach maximum photocurrent is much shorter than that of the solar cell pretreated at negative bias. The transient photocurrent responses to the sequence of single-light-pulses also show that there is obvious carrier trapping in a positive bias treated device, which indicates that defect induced carrier trapping is the critical factor for the perovskite solar cells with an n-TiOx electron transport layer. In order to improve the performance of the perovskite solar cells with nano-TiOx ETL, it is very necessary to significantly reduce defects. Our results also demonstrate that cation accumulation at the interface between the perovskite active layer and ETL can enhance the device performance to a certain extent.The ion migration in perovskite materials has been extensively studied by researchers, but the charge dynamic distribution caused by ion migration and carrier trapping is partly unclear. 相似文献
1000.
Jia Li Guan Wang Yu Qin Xue Zhang Hai-Feng Wang Hong-Wei Liu Ling-Juan Zhu Xin-Sheng Yao 《RSC advances》2020,10(53):32043
Five new compounds including three new cannabinoids, cannabisativas A–C (1–3), two new phenolic acids, (7Z,9Z)-cannabiphenolic acid A (4) and (8S,9Z)-cannabiphenolic acid B (5), together with twelve known compounds (6–17), were isolated from the aerial parts of Cannabis sativa L. subsp. sativa. The structures of 1–5 were established on the basis of extensive 1D, 2D NMR and HRESIMS analysis. The absolute configurations were determined by comparison between their experimental and calculated spectra of electronic circular dichroism (ECD) or the modified Mosher''s method. The neuroprotective effects of the compounds 1–17 were evaluated on PC 12 cells. Compounds 12, 13 and 15 showed potential protective effects against H2O2-induced damage.5 new compounds including 3 new cannabinoids, cannabisativas A–C, 2 new phenolic acids, (7Z,9Z)-cannabiphenolic acid A and (8S,9Z)-cannabiphenolic acid B, together with 12 known compounds, were isolated from the aerial parts of Cannabis sativa L. subsp. sativa. 相似文献