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91.
Application of diffusional kurtosis imaging to detect occult brain damage in multiple sclerosis and neuromyelitis optica
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Wenshu Qian Koon Ho Chan Edward S. Hui Chi Yan Lee Yong Hu Henry Ka‐Fung Mak 《NMR in biomedicine》2016,29(11):1536-1545
Multiple sclerosis (MS) and neuromyelitis optica (NMO) are two common types of inflammatory demyelinating disease of the central nervous system. Early distinction of NMO from MS is crucial but quite challenging. In this study, 13 NMO spectrum disorder patients (Expanded Disability Status Scale (EDSS) of 3.0 ± 1.7, ranging from 2 to 6.5; disease duration of 5.3 ± 4.7 years), 17 relapsing–remitting MS patients (EDSS of 2.6 ± 1.4, ranging from 1 to 5.5; disease duration of 7.9 ± 7.8 years) and 18 healthy volunteers were recruited. Diffusional kurtosis imaging was employed to discriminate NMO and MS patients at the early or stable stage from each other, and from healthy volunteers. The presence of alterations in diffusion and diffusional kurtosis metrics in normal‐appearing white matter (NAWM) and diffusely increased mean diffusivity (MD) in the cortical normal‐appearing gray matter (NAGM) favors the diagnosis of MS rather than NMO. Meanwhile, normal diffusivities and kurtosis metrics in all NAWM as well as increases in MD in the frontal and temporal NAGM suggest NMO. Our results suggest that diffusion and diffusional kurtosis metrics may well aid in discriminating the two diseases. 相似文献
92.
WANG Cheng DU Hang-gen YIN Li-chun HE Min ZHANG Guo-jun TIAN Yong HAO Bi-fie 《中华创伤杂志(英文版)》2013,16(4):221-224
Objective: The management of se- condary normal pressure hydrocephalus (sNPH) is controversial. Many factors may affect the surgery effect. The purpose of this study was to identify the possible fac- tors influencing prognosis and provide theoretical basis for clinical treatment of sNPH. Methods: A retrospective study was carried out to investigate the results of 31 patients with sNPH who under- went ventriculoperitoneal shunt surgery from January 2007 to December 2011. We processed the potential influencing factors by univariate analysis and the result further by mul- tivariate logistic regression analysis. Results: Factors including age, disease duration and Glasgow coma scale (GCS) score before surgery significantly influenced the prognosis of sNPH (P〈0.05). Further logistic regression analysis showed that all the three factors are independent influencing factors. Conclusion: Age, disease duration and GCS score before surgery have positive predictive value in estimating favorable response to surgical treatment for sNPH. 相似文献
93.
The cytotoxicity and genotoxicity of soluble and particulate cobalt in human lung epithelial cells
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Hong Xie Leah J. Smith Amie L. Holmes Tongzhang Zheng John Pierce Wise Sr. 《Environmental and molecular mutagenesis》2016,57(4):282-287
Cobalt is a toxic metal used in various industrial applications leading to adverse lung effects by inhalation. Cobalt is considered a possible human carcinogen with the lung being a primary target. However, few studies have considered cobalt‐induced toxicity in human lung cells, especially normal lung epithelial cells. Therefore, in this study, we sought to determine the cytotoxicity and genotoxicity of particulate and soluble cobalt in normal primary human lung epithelial cells. Cobalt oxide and cobalt chloride were used as representative particulate and soluble cobalt compounds, respectively. Exposure to both particulate and soluble cobalt induced a concentration‐dependent increase in cytotoxicity, genotoxicity, and intracellular cobalt ion levels. Based on intracellular cobalt ion levels, we found that soluble and particulate cobalt induced similar cytotoxicity while soluble cobalt was more genotoxic than particulate cobalt. These data indicate that cobalt compounds are cytotoxic and genotoxic to human lung epithelial cells. Environ. Mol. Mutagen. 57:282–287, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
94.
95.
Glaucoma-related population-based studies from Japan, Mongolia, India, Singapore, Thailand, China, Bangladesh, Myanmar, Sri Lanka, and South Korea show a higher glaucoma prevalence in Asian patients, including a higher incidence of primary angle-closure glaucoma, than in white patients, although primary open-angle glaucoma (POAG) is still the most commonly reported. Among POAG, normal tension glaucoma predominates over high tension glaucoma, a distinctive finding. Risk factors for glaucoma in population-based studies in both Asian and white patients are similar, except that myopia is a greater risk factor in Asian patients. Diagnostic criteria differ among studies, some using the International Society of Geographic and Epidemiologic Ophthalmology (ISGEO) classification and others not. The devices used to observe the optic disk and test the visual field are also not uniform across studies. Moreover, the ages of patients, and whether rural or urban, were different. To allow reliable comparison of the results of epidemiologic studies, efforts to standardize the diagnostic criteria, devices, and the age range of the study population are required. 相似文献
96.
Roddy McDermid 《Anaesthesia and Intensive Care Medicine》2021,22(7):454-462
97.
��������������� 《中国实用口腔科杂志》2012,5(12):751-754
??Abstract??Objective To obtain the data of dental measurements in healthy Bai teenagers. Methods Normal dentognathic models were obtained in 97 teenagers. The width of the tooth crown and the size of the dental arch were measured with a venier. The measurments were statistically analysed. Results The tooth crown in boys was wider than that in girls except first premolar and second premolar;the dental arch width and length in boys were wider than those in girls.There was no significant difference in Bolton index and Pont index between boys and girls. Conclusion The norms of teeth??denal arch and dentition index on normal occlusion in Bai teenagers have been established?? and they have a certain reference value to guide clinical orthodontics. 相似文献
98.
High‐definition OCT (HD‐OCT) is an innovative technique based on the principle of conventional OCT. Our objective was to test the resolution and image quality of HD‐OCT in comparison with reflectance confocal microscopy (RCM) of healthy skin. Firstly, images have been made of a ultra‐high‐resolution line‐pair phantome with both systems. Secondly, we investigated 21 healthy volunteers of different phototypes with HD‐OCT and RCM on volar forearm and compared the generated images. HD‐OCT displays also differences depending on the skin phototype and anatomical site. The 3‐μm lateral resolution of the HD‐OCT could be confirmed by the phantom analysis. The identification of cells in the epidermis can be made by both techniques. RCM offers the best lateral resolution, and HD‐OCT has the best penetration depth, providing images of individual cells deeper within the dermis. Eccrine ducts and hair shafts with pilosebaceous units can be observed depending on skin site. HD‐OCT provides morphological imaging with sufficient resolution and penetration depth to permit visualization of individual cells at up to 570 μm in depth offering the possibility of additional structural information complementary to that of RCM. HD‐OCT further has the possibility for rapid three‐dimensional imaging. 相似文献
99.
J. Almekinder W. Manda D. Soko Y. Lan D. R. Hoover R. D. Semba 《Scandinavian journal of clinical and laboratory investigation》2013,73(3):199-204
Fasting growth hormone (GH) levels and GH responses to exercise were studied in normally menstruating women and in women taking oral contraceptives in order to find out whether the GH levels were related to the menstrual cycle or changed by oral contraceptives. The GH response to exercise was found to be higher when exercise was done in the midcycle period than when it was done at other points of time during the normal menstrual cycle. Fasting GH levels were unchanged throughout the menstrual cycle. Fasting GH levels and GH responses to exercise performed outside the midcycle period were identical in normally menstruating women and in women taking oral contraceptives. In conclusion, the GH response to exercise, but not fasting GH levels, were related to the menstrual cycle. The estrogen and progestin components of the contraceptives used in this study were balanced in such a way that the growth hormone levels and growth hormone responses to exercise were not changed by long-term therapy with these drugs. 相似文献
100.
目的建立北京地区健康成年女性的跟骨骨超声速率(speed of sound,SOS)的正常参考值。方法用日本吉野电器公司生产的CM-100型跟骨骨超声测定仪对912名北京地区健康女性志愿者进行跟骨SOS测定,并对其中110名志愿者用双能X线骨密度仪(DXA)进行腰椎I_(2-4)和髋部的骨密度测定。结果健康女性跟骨SOS在26~30岁年龄组达到峰值[(1 533.4±34.2)m/s],达峰值后开始下降,46~50岁后下降速度加快。绝经期前、后跟骨SOS差异有统计学意义。跟骨SOS下降分为快速下降期、稳定下降期和再下降期。经DXA测定的骨密度值与跟骨SOS值相关(r=0.323~0.506,P0.01)。结论本研究建立了北京地区健康妇女跟骨SOS正常值,跟骨SOS和DEXA测定骨密度之间存在良好的相关性。 相似文献