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1.
Near-infrared diffuse correlation spectroscopy/tomography (DCS/DCT) has recently emerged as a noninvasive measurement/imaging technology for tissue blood flow. In DCT studies, the high-dense collection of light temporal autocorrelation curves (g2(τ)) via fiber array are critical for image reconstruction of blood flow. Previously, the camera-based fiber array limits the field of view (FOV), precluding its applications on large-size human tissues. The line-shape fiber probe based on lens combination, which is predominantly used in current DCT studies, requires rotated-scanning over the surface of target tissue, substantially prolonging the measurement time and increasing the system instability. In this study, we design a noncontact optical probe for DCT based on collimating micro-lens fiber array, termed as FA-nc-DCT system. For each source/detector fiber, a single optical path was collimated by coupling with one micro-lens in the fiber array that is integrated in a square-shape base. Additionally, an 8×8 optical switch is used to share the hardware laser and detectors without spatial scanning. The FA-nc approach for the precise collection of g2(τ) curves was validated through a speed-varied phantom experiment and the human experiments of cuff occlusion, from which the expected value of the blood flow index (BFI) was obtained. Furthermore, the flow anomaly in the phantom and the ischemic muscle in human were accurately reconstructed from the FA-nc-DCT system, which is combined with the imaging framework based on the Nth-order linear algorithm that we recently created. Those outcomes demonstrated the great potential of FA-nc-DCT technology for fast and robust imaging of various diseases such as human breast cancers. 相似文献
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Ling Zhang Xue-Jun Shang Hong-Fei Li Yu-Qin Shi Wei Li Maria E Teves Zhi-Qiong Wang Gao-Feng Jiang Shi-Zhen Song Zhi-Bing Zhang 《Asian journal of andrology》2015,17(1):86-93
Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1''s action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1. 相似文献
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目的探讨早期联用美罗培南(MEP)和大剂量重组人生长激素(rhGH)对严重烫伤免疫抑制大鼠肠源性感染的影响。方法Wistar大鼠54只随机分为对照组、烧伤组和治疗组(C1组、C2组、C3组),后两大组制成25%总体表面积(TBSA)Ⅲ°烫伤免疫抑制模型,伤后2h给予rhGH1.33IU/kg、MEP20mg/kg,伤后8、24h检测门静脉血清内毒素(LPS)、腔静脉血清肿瘤坏死因子-α(TNF-α)含量,肝功能变化和肠道细菌移位率。结果C3(MEP+rhGH治疗)组LPS和TNF-α含量均显著低于其他组(P<0.01),与对照组差异无统计学意义(P>0.05),C3组未发现肠道细菌移位且肝功能检测指标显著低于其他组(P<0.01),与对照组差异无统计学意义(P>0.05)。结论早期联用MEP和rhGH治疗严重烫伤免疫抑制大鼠能显著减轻或防止肠道细菌/内毒素移位,减少炎症介质释放,保护脏器功能。 相似文献
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猕猴桃汁抗环磷酰胺致突变作用的机理 总被引:12,自引:1,他引:11
目的用大鼠外周血双核淋巴细胞微核测试法(CBMNT),在哺乳动物整体水平,研究猕猴桃汁抗环磷酰胺(CP)的致突变作用以及生物转化Ⅱ相酶的作用。方法测定大鼠外周血双核淋巴细胞微核细胞率及肝组织中总谷胱甘肽硫转移酶(GST)、尿苷二磷酸葡萄糖醛酸转移酶(UDPGT)、谷氨酰胺转肽酶(γGT)活性。结果猕猴桃汁对CP诱发的大鼠外周血双核淋巴细胞微核细胞率有显著抑制作用,能明显诱导大鼠肝脏总GST、UDGTP活性,但对γGT活性无显著影响。大鼠外周血双核淋巴细胞微核细胞率与总GST、UDGTP活性呈明显负相关。结论猕猴桃汁抗CP致微核形成作用的机理可能是通过诱导机体外来化合物代谢解毒酶系,加速CP的代谢灭活 相似文献
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二甲基亚砜诱导人肝癌细胞BEL-7402凋亡的研究 总被引:2,自引:0,他引:2
目的 :研究二甲基亚砜 (DMSO)对人肝癌细胞凋亡的诱导作用。方法 :用不同浓度的DMSO处理体外培养的人肝癌细胞BEL 74 0 2 ,应用普通光镜、荧光显微镜、MTT分析方法和流式细胞技术 (FCM )检测肝癌细胞凋亡的形态学变化、细胞存活率、凋亡百分率和细胞周期分布的变化。结果 :DMSO诱导BEL 74 0 2细胞核DNA凝缩和核片段化 ,最后形成凋亡小体 ;随着DMSO浓度的增加和处理时间的延长 ,细胞存活率明显下降 ,其IC50 为 1.9% ;2 %的DMSO处理细胞 12h ,凋亡率达 17.2 1% ,同时S期细胞明显增加 ,G2 M期细胞明显下降。结论 :DMSO可诱导人肝癌细胞凋亡 ,并使细胞受阻于S期而进入凋亡程序。 相似文献
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目的:探讨膀胱三角区壁瓣成形尿道治疗女性外伤性尿道损伤的疗效。方法:自膀胱颈后唇向上,取梯字形壁瓣,形成锥状管,经膀胱颈口,自阴道前壁外拉至外阴部,在原尿道外口处固定,替代尿道。结果:3例随访8年,1例6年,1例5年,平均随访7年,均排尿通畅,无尿失禁和尿道狭窄。结论:女性外伤性尿道缺损,应用膀胱三角区壁瓣形成锥状管替代尿道法治疗,手术简单,对患者打击小,成功率高,远期效果好。 相似文献
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N Diehm A Shang A Silvestro D-D Do F Dick J Schmidli F Mahler I Baumgartner 《European journal of vascular and endovascular surgery》2006,31(1):59-63
OBJECTIVES: Aim of this study is to correlate distribution pattern of lower limb atherosclerosis with cardiovascular risk factor profile of patients with peripheral arterial occlusive disease (PAD). PATIENTS AND METHODS: Analysis is based on a consecutive series of 2659 patients (1583 men, 1076 women, 70+/-11 years) with chronic PAD of atherosclerotic origin undergoing primary endovascular treatment of lower extremity arteries. Pattern of atherosclerosis was grouped into iliac (n=1166), femoropopliteal (n=2151) and infrageniculate (n=888) disease defined according to target lesions treated. A multivariable multinomial logistic regression analysis was performed to assess relation with age, gender and classical cardiovascular risk factors (diabetes mellitus, arterial hypertension, hypercholesterolemia, cigarette smoking) using femoropopliteal disease as reference. RESULTS: Iliac disease was associated with younger age (RRR 0.95 per year of age, 95%-CI 0.94-0.96, p<0.001), male gender (RRR 1.32, 95%-CI 1.09-1.59, p=0.004) and cigarette smoking (RRR 2.02, 95%-CI 1.68-2.42, p<0.001). Infrageniculate disease was associated with higher age (RRR 1.02, 95%-CI 1.01-1.02, p<0.001), male gender (RRR 1.23, 95%-CI 1.06-1.41, p=0.005) and diabetes mellitus (RRR 1.68, 95%-CI 1.47-1.92, p<0.001). Hypercholesterolemia was less prevalent in patients with lesions below the knee (RRR 0.82, 95%-CI 0.71-0.94, p=0.006), whereas no distinct pattern was apparent related to arterial hypertension. CONCLUSION: Clinical phenotype of peripheral atherosclerosis varies with prevalence of cardiovascular risk factors suggesting differences in mechanisms involved in iliac as compared with infrageniculate lesions. Identification of molecular mechanism might have influence on future therapeutic strategies in PAD patients. 相似文献
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请客做东的朋友,点菜的时刻也许是他们最煞费心机的时候:一边是担心点的菜没有特色、不好吃而令客人扫兴,一边又怕菜价太高,“钱袋子”不堪负荷。如果不想遭遇这种尴尬,吃自助餐可能是最好的选择。[编者按] 相似文献