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101.
Giuliana Properzi Sandro Franca Villa Gianfranco Poccia Paolo Aloisi Xu-Hong Gu Giorgio Terenghi Julia M. Polak 《The Journal of pathology》1993,169(2):269-277
Diabetic neuropathy affects both sensory and autonomic peripheral nerve fibres. Vasoactive intestinal polypeptide (VIP) is present in autonomic fibres which modulate sweat secretion, while calcitonin gene-related peptide (CGRP) is localized to cutaneous sensory fibres. In this study, immunohistochemistry and image analysis were used to assess changes of VIP and CGRP, and of the pan-neuronal marker protein gene-product (PGP)-9.5, in skin biopsies of 18 patients affected by type 1 diabetes (age range 18–46 years) and from seven aged-matched controls. Patients were divided into three groups: group 1 (n=6), with diabetes for 6 months to 3 years; group 2 (n=5), with the disease for 5–10 years; and group 3 (n=7), with diabetes for more than 10 years. VIP immunoreactivity (IR) and PGP-9.5-IR were significantly reduced around sweat glands (P <0.005) in groups 2 and 3. Epidermal CGRP-IR and PGP-9.5-IR were significantly reduced in group 3 (P <0.05). Twenty-eight per cent (5/18) of all patients showed high VIP-IR around sweat glands (>95 per cent confidence limits of controls) and all of these patients had diabetes for less than 3 years. Conversely, 55 per cent (10/18) of patients had low VIP-IR (<5 per cent confidence limit of controls). The latter, compared with the former, showed a significantly longer duration of diabetes (Fisher exact test P=0·002), presence of clinical autonomic neuropathy (Fisher exact test P=0.04), and a reduced sural nerve conduction velocity (Fisher exact test P=0.04). These results suggest that quantitative immunohistochemical analysis of peptide-containing cutaneous nerves allows an objective evaluation of nerve fibre alterations at early stages of diabetes than is currently possible with neurophysiological functional tests. 相似文献
102.
一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征 总被引:1,自引:0,他引:1
合成了一系列分子量较低的聚乙二醇.聚己内酯-聚乙二醇(Poly(ethylene glycol)-Polycaprolactone-Poly(ethylene glycol),PEG-PCL—PEG)三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性,当水溶液浓度高于临界凝胶浓度(Critical gel concentration,CGC)时,随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度,以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件,可以在一定程度上拓宽凝胶-溶胶转变温度范围,有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。 相似文献
103.
用X线形态学测量方法,对乌鲁木齐部分维吾尔族长寿老人及其家族成员的第二掌骨骨皮质进行了测量。结果表明10 ̄39岁组骨皮质厚度,皮质厚度指数,皮质面积随年龄增长而增大,30 ̄39岁组达到峰值,其中骨皮质厚度、皮质面积的数值男性〉女性,30 ̄39岁组差别有显著性。40岁以后各组数值开始下降,其下降速度女性快于男性,90岁以上组最为明显,有显著性差异。 相似文献
104.
TiO(2) coatings were prepared on NiTi alloy by heat treatment in air at 300, 400, 600 and 800 degrees C. The heat-treated NiTi alloy was subsequently immersed in a simulated body fluid for the biomimetic deposition of the apatite layer onto the surface of TiO(2) coating. The apatite coatings as well as the surface oxide layer on NiTi alloy were characterized using scanning electron microscopy equipped with energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy. Results showed the samples heat-treated at 600 degrees C produced a layer of anatase and rutile TiO(2) on the surface of NiTi. No TiO(2) was detected on the surface of NiTi after heat treatment at 300 and 400 degrees C by X-ray diffraction, while rutile was formed on the surface of the 800 degrees C heat-treated sample. It was found that the 600 degrees C heat-treated NiTi induced a layer consisted of microcrystalline carbonate containing hydroxyapatite on its surface most effectively, while 300 and 400 degrees C heat-treated NiTi did not form apatite. This was due to the presence of anatase and/or rutile in the 600 and 800 degrees C heat-treated NiTi which could provide atomic arrangements in their crystal structures suitable for the epitaxy of apatite crystals, and anatase had better apatite-forming ability than rutile. XPS and Raman results revealed that this apatite layer was a carbonated and non-stoichiometric apatite with Ca/P ratio of 1.53, which was similar to the human bone. The formation of apatite on 600 degrees C heat-treated NiTi following immersion in SBF for 3 days indicated that the surface modified NiTi possessed excellent bioactivity. 相似文献
105.
人和大鼠腰椎关节突关节的SP能神经纤维的分布 总被引:2,自引:0,他引:2
目的:证实支配腰椎关节突关节的神经支配和化学性质,方法:用逆行荧光素标记结合免疫组化法,研究7只大鼠腰部脊神经节细胞的周围突分支投射到腰椎关节突关节及其递质性质以及3例人腰椎关节突关节囊上神经末梢的化学性质,结果:发现大鼠一侧L5和L6之间的关节突关节受同侧L2-5节段的脊神经节的部分细胞周围突分支支配,其中有33.399%的中型和小型细胞为中SP能免疫反应阳性,人的关节突关节囊含有SP阳性的神经 相似文献
106.
老年学习记忆减退大鼠齿状回突触的定量研究 总被引:2,自引:0,他引:2
据老年大鼠在Morris水迷宫中的行为表现,将其分为老年学习记忆减退和学习记忆正常两部分,采用透射电镜观察、拍片,对齿状回中分子层触的数量和大小进行体视学定量分析。 相似文献
107.
Five novel mutations in the L1CAM gene in families with X linked hydrocephalus. 总被引:2,自引:2,他引:2 下载免费PDF全文
S M Gu U Orth A Veske H Enders K Klunder M Schlosser W Engel E Schwinger A Gal 《Journal of medical genetics》1996,33(2):103-106
Five novel mutations have been identified in the gene encoding L1CAM, a neural cell adhesion protein, in families with X linked hydrocephalus (XHC). Interestingly, all five mutations are in the evolutionarily highly conserved Ig-like domains of the protein. The two frameshift mutations (52insC and 955delG) and the nonsense mutation (Trp276Ter) most probably result in functional null alleles and complete absence of L1CAM at the cell surface. The two missense mutations (Tyr194Cys and Pro240Leu) may considerably alter the structure of the L1CAM protein. These data provide convincing evidence that XHC is genetically extremely heterogeneous. 相似文献
108.
Guodong Chen Shuxue Zhou Guangxin Gu Limin Wu 《Macromolecular chemistry and physics.》2005,206(8):885-892
Summary: Silica sols were first prepared based on different ratios of tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES) by an acid‐catalyzed sol–gel process, and then incorporated into acrylic‐based polyurethanes. The structures and morphologies of silicone‐oxo clusters were studied by 29Si NMR, SAXS, and scanning electron microscopy (SEM), whereas the mechanical properties of polyurethane/silica hybrids were characterized by DMA and tensile tests. The silicone‐oxo clusters in both silica sol and polyurethane hybrids became denser and larger at a higher molar ratio of TEOS/MTES and higher silica content, and the silica‐oxo clusters of polyurethane/silica hybrids even became more compact and larger than those of silica sols, increasing the elastic modulus and tensile strength of polyurethane/silica hybrids.
109.
中药“神经再生素”促神经生长过程中基因差异性表达的初步研究 总被引:20,自引:1,他引:20
为了探索中药“神经再生素”促神经生长过程中基因水平的变化。本实验采用 dd-PCR方法 ,从体外培养背根神经节细胞加药组和不加药组中获得两者的差异表达片段 ,并经反杂交筛选、克隆测序、DNA序列检索分析、Northern验证。结果表明 ,差异显示共获得 8个差异条带 ,一个为下调基因 ,其余为上调基因 ,其中 2个 c DNA序列与 RRAJ5 16 1基因 (增殖相关基因 )、AF196 3 15基因 (锌指样蛋白 DDP2 ) 10 0 %同源 ,2个 c DNA序列与 AK0 0 175 7基因、STA5 SRR基因 (t RNA合成酶 )部分同源。结论是中药“神经再生素”在促神经生长过程中 ,对神经元基因的选择性表达起着重要的调控作用。 相似文献
110.
本文制备了巨噬细胞条件培养基(MφCM),并应用快速自动比色微量分析法检测MφCM对体外培养的生后7dSD大鼠小脑皮质神经元的作用。结果表明,分子量大于10kD的MφCM对神经元(细胞密度1×106/ml)的作用,与对照组比较有明显的神经营养活性(F<0.05);用盖玻片培养法表明,该组份有促进神经元突起生长的作用。MφCM经SephacrylS-100-HR凝胶层析和生物活性鉴定,获得了具有神经营养活性的第二峰洗脱液。此洗脱液经SDS-聚丙烯酰胺凝胶电泳分析,证明MφCM中神经营养活性成份的蛋白质其分子量为31kD-68kD之间。 相似文献