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91.
目的 分析干眼发病分布状况、相关危险因素和临床特点等,为干眼的预防和临床诊断治疗提供依据。方法 对眼科门诊112例干眼患者作问卷调查,并进行泪液分泌实验、泪膜破裂时间测定和角膜荧光素染色检查。结果 112例患者中男31例,女81例;干眼患者检出率随年龄增长呈上升趋势;长期局部应用滴眼药、过度用眼、慢性眼表疾病、结缔组织病、糖尿病等与干眼症发病密切相关。结论 干眼症的发生与性别、年龄等多种因素相关,预防性治疗对于干眼症状的缓解具有重要意义。 相似文献
92.
This paper presents a photogrammetry-based volume measurement framework for the particle density estimation of Lightweight expanded clay aggregate (LECA). The results are compared with computed tomography (CT) and Archimedes’ method measurements. All of the steps required in order to apply the proposed approach are explained. Next, we discuss how the interpretation of open pores affects the results of volume measurements. We propose to process the shapes obtained from different methods by applying an Ambient Occlusion algorithm with the same threshold, t = 0.175. The difference between the CT and SfM methods is less than 0.006 g/cm3, proving that the photogrammetry-based approach is accurate enough. The Archimedes’ method significantly overestimates the density of the particles. Nevertheless, its accuracy is acceptable for most engineering purposes. Additionally, we evaluate the accuracy of shape reconstruction (in terms of the Hausdorff distance). For 95% of the grain’s surface, the maximum error is between 0.073 mm and 0.129 mm (depending on the grain shape). The presented approach is helpful for measuring the particle density of porous aggregates. The proposed methodology can be utilized in order to estimate intergranular porosity, which is valuable information for the calibration of DEM models. 相似文献
93.
Brian L Sprague Amy Trentham-Dietz Curtis J Hedman Jue Wang Jocelyn DC Hemming John M Hampton Diana SM Buist Erin J Aiello Bowles Gale S Sisney Elizabeth S Burnside 《Breast cancer research : BCR》2013,15(3):R45
Introduction
Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk).Methods
We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264). Subjects completed a questionnaire and provided a blood sample that was analyzed for mono-ethyl phthalate, mono-butyl phthalate, mono-benzyl phthalate, butyl paraben, propyl paraben, octylphenol, nonylphenol, and bisphenol A (BPA). Percentage breast density was measured from mammograms by using a computer-assisted thresholding method.Results
Serum BPA was positively associated with mammographic breast density after adjusting for age, body mass index, and other potentially confounding factors. Mean percentage density was 12.6% (95% confidence interval (CI), 11.4 to 14.0) among the 193 women with nondetectable BPA levels, 13.7% (95% CI, 10.7 to 17.1) among the 35 women with detectable levels below the median (<0.55 ng/ml), and 17.6% (95% CI, 14.1 to 21.5) among the 34 women with detectable levels above the median (>0.55 ng/ml; Ptrend = 0.01). Percentage breast density was also elevated (18.2%; 95% CI, 13.4 to 23.7) among the 18 women with serum mono-ethyl phthalate above the median detected level (>3.77 ng/ml) compared with women with nondetectable BPA levels (13.1%; 95% CI, 11.9 to 14.3; Ptrend = 0.07). No other chemicals demonstrated associations with percentage breast density.Conclusions
Postmenopausal women with high serum levels of BPA and mono-ethyl phthalate had elevated breast density. Further investigation of the impact of BPA and mono-ethyl phthalate on breast cancer risk by using repeated serum measurements or other markers of xenoestrogen exposure are needed. 相似文献94.
95.
96.
97.
痒疹样营养不良型大疱性表皮松解症一家系调查 总被引:4,自引:4,他引:0
报告痒疹样营养不良型大疱性表皮松解症一家系调查结果。该家系共5代34名成员,其中患病者15例(男8例,女7例),属常染色体显性遗传。先证者,女性,18岁。于1岁左右双踝部出现数个水疱,双胫前皮肤在外伤、搔抓后形成圆形或卵圆形丘疹、结节,似米粒至花生米大,暗红色,质地较硬,部分皮损表面有痂壳。双足多个趾甲增厚或脱失。皮损组织病理学表现为多处表皮下裂隙形成,真皮内散在较多的表皮样囊肿,并有少量淋巴细胞浸润。该家系中其他患者的皮损与先证者类似。 相似文献
98.
目的 探讨高糖环境对体外培养的人肾小球系膜细胞(HMC)表达结缔组织生长因子(CTGF)及其受体--低密度脂蛋白受体相关蛋白(LRP)的影响以及相应的信号机制。方法 以体外培养的HMC为研究对象,采用双抗体夹心酶联免疫吸附法(ABC ELISA)测定正常糖组(NG组)、高糖组(HG组)和甘露醇组(MG组)培养液中CTGF、人磷酸化细胞外信号调节激酶(pERK)及LPR的浓度变化,分别观察高糖环境对系膜细胞CTGF蛋白表达、丝裂素激活蛋白激酶(MAPKS)信号通路的活化以及CTGF受体LRP表达的影响。结果 HMC本身存在基础水平的CTGF蛋白表达,HG组培养1d后,CTGF蛋白表达升高,峰值出现在第3天,自第4天开始下降;而NG组、MG组的CTGF蛋白表达未随时间发生显著变化;高糖环境下HMC外信号调节激酶(ERK)出现动态活化:1h即开始检测到pERK升高,峰值出现在第8至24小时,于48h内降至基础水平,而NG组、MG组在各时点均未能检测到pERK表达;加入ERK活化特异抑制剂PD98059后发现高糖环境对HMC表达CTGF蛋白增加的影响被抵消;另外,高糖环境未影响LRP的表达。结论 高糖环境下HMC表达CTGF蛋白增加,但未增加CTGF受体LRP的表达,初步明确CTGF的高表达是通过磷酸化激活ERK实现的。 相似文献
99.
To explore the functions of very low density lipoprotein receptor (VLDL-R) subtype Ⅱ in lipoprotein metabolism and foam cells formation, the recombinant plasmid with the two subtypes cDNA was constructed respectively, the ldl A7 cell lines were transfected and two cell lines expressing VLDL-R were obtained: one stably expressing the VLDLR with the O-linked sugar region (type Ⅰ VLDLR) and the other without the O-linked sugar region (type Ⅱ VLDLR). In the study on binding of VLDLR to their nuclein labeled natural ligands (VLDL and β-VLDL), it was found that surface binding of^125I-VLDL or ^125I-β-VLDL of ldl-A7 cells transfected with type Ⅰ VLDLR recombinant (ldl-A7-VRI) was more higher than that of ldl-A7 cells transfected with type Ⅱ VLDLR recombinant (ldl-A7 VRⅡ). After being incubated with VLDL for different time, the contents of triglyceride and total cholesterol in cells were mensurated, and the formation of foam cells and accumulation of lipid in cells was observed by oil-red O staining. The results showed that the contents of triglyceride and total cholesterol in IdI-A7-VR Ⅰ were much higher than those in ldl-A7-VR Ⅱ, and IdI-A7-VR Ⅰ could transform into foam cells notably. It was suggested that type Ⅰ VLDLR binds with relative higher affinity to VLDL and β-VLDL, and internalizes much more lipoprotein into cells. As a result, we can conclude that type Ⅰ VLDLR plays a more important role in lipoprotein metabolism and foam cells formation than type Ⅱ VLDLR。 相似文献
100.
'The VaSCtilar myelopathy is me~ng with bang,which has atheted attention in China and other.ountri..[l]. Previous studies were involVed the sourceand ~ of the outside nIOOd submIt to the suitalcold, but there is no systematic ~ on the qUantitativecapilleq denSity in the spinal conl[2]. The aim Of thisstudy is to observe the capilleq denSity in diffemonffeage acs and explore the changes of the capillapdensity in the spinal cOld and PIDvide morpholopcal reference for the basic study on the… 相似文献