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81.
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目的探讨内镜除皱术与传统除皱术相结合的治疗方式及效果。方法仅存在额部皱纹、眉间纹及眉下垂者采用内镜额部除皱术,切除或切断皱眉肌、降眉肌和额肌,必要时结合额部皮瓣上提悬吊技术即可;如同时存在中下面部皮肤老化、松弛下垂,则内镜额部除皱术尚需结合传统切开法的中面部或中下面部除皱术,做浅表肌腱膜系统(sMAs)筋膜的折叠或切除缝合,以及多余皮肤的切除剪裁。结果104例采用额部内镜除皱术,均取得良好的除皱和眉提升效果。并发症较少而轻微,包括表情肌去除部位的轻度凹陷、额部皮肤麻木、发际线轻微后移、皱纹去除不彻底等。无面神经颞支损伤等严重并发症发生。其中84例存在中下面部皮肤松弛下垂,在做内镜额部除皱的同时行耳前切口的传统除皱术,明显改善中下面部的皮肤老化,并使面部上下的年轻化协调一致。结论内镜额部除皱术设计合理、操作安全、效果明确,是一项切口小、损伤轻的微创技术,符合整形外科的发展趋势。对于同时存在有中下面部皮肤松弛者,如能结合传统切开法除皱术,面部年轻化的整体效果可进一步优化。 相似文献
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目的 探讨高剂量D- 半乳糖复制C57BL/6J 衰老小鼠模型的效果。方法 选用30 只9 周龄雄
性C57BL/6J 小鼠,随机分为3 组:500 mg/(kg·d)D- 半乳糖组、1 000 mg/(kg·d)D- 半乳糖组及对照
组,持续皮下注射8 周后解剖小鼠,测定血液和组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSHPx)
及丙二醛(MDA)等,Western blotting 检测组织中血红素加氧酶-1(HO-1)的表达,并对部分组织行
苏木精- 伊红染色。结果 1 000 mg/(kg·d)D- 半乳糖组小鼠出现不同程度的脱毛现象。D- 半乳糖组小
鼠的SOD 和GSH-Px 低于对照组(P <0.05),而MDA 和HO-1 高于对照组(P <0.05)。D- 半乳糖组小鼠肝、
脑组织有不同程度的衰老相关病理学改变。结论 D- 半乳糖可以成功诱导小鼠衰老,是复制小鼠衰老模型
的较好选择。 相似文献
86.
目的 观察血管活性肠多肽(VIP)对老龄勃起功能障碍(ED)大鼠的作用及其机制。方法40只SPF级雄性SD大鼠饲养至18月龄构建老龄模型大鼠,采用阿扑吗啡实验筛选老龄ED大鼠,阿扑吗啡实验结果阳性的老龄勃起功能正常大鼠为正常组,实验结果阴性的老龄ED大鼠为ED组和干预组,每组7只。干预组大鼠使用VIP 25 ng/kg隔日腹腔注射,治疗28 d。检测阴茎海绵体内压(ICP)及平均动脉压(MAP)评估勃起功能;酶联免疫吸附法检测大鼠阴茎海绵体组织环磷酸腺苷(cAMP)、一氧化氮(NO)含量;组织免疫荧光技术(IF)测大鼠阴茎海绵体组织血管性血友病因子(vWF)表达水平;蛋白质印迹法检测海绵体蛋白激酶A (PKA)、内皮源性一氧化氮合酶(eNOS)、血管性血友病因子(vWF)及血管内皮生长因子(VEGF)蛋白表达水平。结果 正常组、ED组和干预组基础ICP分别为(20.41±5.92)mmHg、(21.76±5.37)mmHg和(18.54±3.97)mmHg(1mmHg=0.133 kPa),MAP分别为(123.52±14.74)mmHg,(118.83±10.97)mmHg和(114... 相似文献
87.
Hylton B. Menz Mohammad R. Fotoohabadi Shannon E. Munteanu Gerard V. Zammit Mark F. Gilheany 《Journal of orthopaedic research》2013,31(3):427-433
Forefoot pain is a common problem in older people. We determined whether plantar pressures during gait and the relative lengths of the lesser metatarsals differ between older people with and without plantar forefoot pain. Dynamic plantar pressure assessment during walking was undertaken using the Tekscan MatScan® system in 118 community‐dwelling older people (44 males and 74 females), mean age 74 (standard deviation = 5.9) years, 43 (36%) of whom reported current or previous plantar forefoot pain. The relative lengths of metatarsals 1–5 were determined from weightbearing X‐rays. Participants with current or previous plantar forefoot pain exhibited significantly (p = 0.032) greater peak plantar pressure under metatarsal heads 3–5 (1.93 ± 0.41 kg/cm2 vs. 1.74 ± 0.48 kg/cm2). However, no differences were found in relative metatarsal lengths between the groups. These findings indicate that older people with forefoot pain generate higher peak plantar pressures under the lateral metatarsal heads when walking, but do not exhibit relatively longer lesser metatarsals. Other factors may be responsible for the observed pressure increase, such as reduced range of motion of the metatarsophalangeal joints and increased stiffness of plantar soft tissues. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 427–433, 2013 相似文献
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Structural architecture supports functional organization in the human aging brain at a regionwise and network level 下载免费PDF全文
Joelle Zimmermann Petra Ritter Kelly Shen Simon Rothmeier Michael Schirner Anthony R. McIntosh 《Human brain mapping》2016,37(7):2645-2661
Functional interactions in the brain are constrained by the underlying anatomical architecture, and structural and functional networks share network features such as modularity. Accordingly, age‐related changes of structural connectivity (SC) may be paralleled by changes in functional connectivity (FC). We provide a detailed qualitative and quantitative characterization of the SC–FC coupling in human aging as inferred from resting‐state blood oxygen‐level dependent functional magnetic resonance imaging and diffusion‐weighted imaging in a sample of 47 adults with an age range of 18–82. We revealed that SC and FC decrease with age across most parts of the brain and there is a distinct age‐dependency of regionwise SC–FC coupling and network‐level SC–FC relations. A specific pattern of SC–FC coupling predicts age more reliably than does regionwise SC or FC alone (r = 0.73, 95% CI = [0.7093, 0.8522]). Hence, our data propose that regionwise SC–FC coupling can be used to characterize brain changes in aging. Hum Brain Mapp 37:2645–2661, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
90.
Accelerated longitudinal gray/white matter contrast decline in aging in lightly myelinated cortical regions 下载免费PDF全文
Didac Vidal‐Piñeiro Kristine B. Walhovd Andreas B. Storsve Håkon Grydeland Darius A. Rohani Anders M. Fjell 《Human brain mapping》2016,37(10):3669-3684
Highly myelinated cortical regions seem to develop early and are more robust to age‐related decline. By use of different magnetic resonance imaging (MRI) measures such as contrast between T1‐ and T2‐weighted MRI scans (T1w/T2w) it is now possible to assess correlates of myelin content in vivo. Further, previous studies indicate that gray/white matter contrast (GWC) become blurred as individuals' age, apparently reflecting age‐related changes in myelin structure. Here we address whether longitudinal changes in GWC are dependent on initial myelin content within tissue as defined by baseline T1w/T2w contrast, and hypothesize that lightly myelinated regions undergo more decline longitudinally. A sample of 207 healthy adult participants (range: 20–84 years) was scanned twice (interscan interval: 3.6 years). Results showed widespread longitudinal reductions of GWC throughout the cortical surface, especially in the frontal cortices, mainly driven by intensity decay in the white matter. Annual rate of GWC blurring showed acceleration with age in temporal and medial prefrontal regions. Moreover, the anatomical distribution of increased rate of GWC decline with advancing age was strongly related to baseline levels of intracortical myelin. This study provides a first evidence of accelerated regional GWC blurring with advancing age, relates GWC patterns to cortical myeloarchitectonics and supports the hypothesis of increased age‐related vulnerability of lightly myelinated areas. Hum Brain Mapp 37:3669–3684, 2016. © 2016 Wiley Periodicals, Inc . 相似文献