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41.
进一步重视脂肪新功能对创面愈合作用的研究 总被引:9,自引:1,他引:8
创面愈合的研究范围正随着相关领域的研究进展而不断拓展和完善。以皮下脂肪组织为例 ,以往多数的研究认为 ,脂肪组织来源于间充质细胞 (mesenchymalcell,MC) ,其功能仅是一个能量贮存仓库。但近年来的研究表明 ,脂肪组织还可能是一个重要的内分泌器官 ,在发育学、信号转导 ,以及干细胞作用等多方面与组织修复存在着密切联系。有专家认为 ,加强对脂肪细胞新功能的研究和开发 ,有可能对创面修复和组织再生机制产生新的认识 ,并寻找出新的促愈合手段。脂肪细胞参与创面愈合首先表现在它可能作为一个内分泌器官。迄今为止 ,已经发现人的脂肪细… 相似文献
42.
Assault-injured Adolescents Presenting to the Emergency Department: Causes and Circumstances 总被引:1,自引:0,他引:1
43.
血瘀证的研究发展脉络与评述 总被引:6,自引:0,他引:6
吴承玉 《南京中医药大学学报》2004,20(3):133-136
主要从4个方面论述了血瘀证50年来研究进展.理论研究,着重从古今文献论述血瘀证定义和含义;客观研究,着重对生理、生化、血液流变学、免疫学、病理学和微循环等方面对血瘀证进行研究;血瘀证的动物模型研究,主要对血瘀证动物模型的建立与造模方法和途径进行研究;诊断标准研究,包括诊断标准、诊断指标的研究。并对上述内容进行了评述,并提出了展望。 相似文献
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[目的 ]探讨细针穿刺乳腺肿瘤组织的端粒酶活性检测在乳腺癌诊断中的意义 .[方法 ]用聚合酶链反应 酶联免疫吸附测定法检测 79例术前乳腺肿瘤细针穿刺活检标本和大体标本的端粒酶活性 ,并与病理诊断进行比较 .[结果 ]乳腺癌 6 5例中穿刺组织端粒酶呈阳性的为 5 7例 ,阳性率为 88% ;大体组织端粒酶呈阳性的为 5 4例 ,阳性率为 83% .淋巴结转移者端粒酶活性高于无淋巴结转移者 .乳腺良性疾病 14例中端粒酶呈阳性的为 2例 ,阳性率为 14 % .[结论 ]术前乳腺肿瘤穿刺组织的端粒酶活性检测有利于乳腺肿瘤的早期诊断及鉴别诊断 . 相似文献
46.
张成 《中国现代神经疾病杂志》2007,7(2):120-125
自从法国医学家Guillaume-Benjamin-Amand Duchenne于1861年首次详细描述Duchenne型肌营养不良(DMD)以来,不少临床医学家和遗传学家对该病进行了系统而深入的研究,虽然已在诊断和遗传咨询方面取得了重大进展,但在治疗上却停滞不前.仍然无法阻止患者进行性加重的肌萎缩和在20岁左右死亡的命运。这是一种既令人感兴趣又使人悲伤的疾病.感兴趣的是其特殊的临床特征和神秘的疾病本质,悲伤的是虽然进行了艰苦的努力但仍无法阻止病情的进展,肌萎缩随着儿童的发育而逐渐进展,随着年龄的增长而加重,在青春期或青年期无一例外地走向生命的终点。[第一段] 相似文献
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B O Cheng R P Trimble R J Illman B A Stone D L Topping 《The British journal of nutrition》1987,57(1):69-76
Adult male rats were fed on diets containing 100 g dietary fibre/kg either as alpha-cellulose or wheat bran or the pericarp-seed coat or aleurone layers prepared from that bran by sequential milling and air elutriation and electrostatic separation. After 10 d, concentrations of total volatile fatty acids (VFA) in caecal fluid were significantly different between groups and fell in the order: aleurone greater than wheat bran greater than pericarp-seed coat greater than cellulose. This ranking probably reflected the ease of fermentation of fibre polysaccharides by colonic bacteria which also resulted in a considerably higher faecal bacterial mass in the aleurone group. Because of the differences in the volume of caecal digesta, the mass of caecal VFA was considerably the highest in the aleurone group, intermediate with wheat bran and equally low in the pericarp-seed coat and cellulose groups. The diet based on aleurone gave a relatively higher proportion of propionate but with both pericarp-seed coat and wheat bran the contribution of butyrate was raised. VFA concentrations in hepatic portal venous plasma were proportional to caecal concentrations with very high (greater than 3 mM) values being recorded in the aleurone group. The findings are discussed in relation to the apparent susceptibility of the morphological components of wheat bran to fermentation by large bowel bacteria. 相似文献
49.
4-Aminopyridine (4-AP) induced an atropine- and tetrodotoxin (TTX)-insensitive contraction (resistant contraction), in a concentration-dependent manner, in the isolated jejunum of rabbits. The failure of specific antagonists of histamine, serotonin and substance P to affect this resistant contraction ruled out the participation of histamine, serotonin and/or substance P. Antiserum against neuropeptide Y (NPY) reduced this resistant contraction in a concentration-dependent manner and inhibited the action of 4-AP totally at a high concentration (1.25% dilution) whereas normal serum lacked this ability. This suggested that the release of NPY was involved in this 4-AP-induced resistant contraction. Radioimmunoassay of NPY-like immunoreactivity in isolated synaptosomal preparations indicated that 4-AP possessed the ability to induce the release of NPY. However, guanethidine did not affect the actions of 4-AP, indicating that NPY is released mainly from non-adrenergic nerves. Our results indicate that 4-AP induces the release of NPY from non-adrenergic nerves to produce an atropine- and TTX-resistant contraction in the isolated jejunum of rabbits. 相似文献
50.
We have previously reported that the J774A.1 macrophage-like tumor cell line produces two potent monokines which stimulate the growth of osteoblasts and chondrocytes. These growth factors, which have an affinity for heparin-agarose, have been termed HEP I (a 30 Kd PDGF-like molecule) and HEP II (an approximately 20 Kd molecule), respectively, based on their elution profile. Unlike HEP I, HEP II does not stimulate the growth of fibroblasts. Extensive biological and chromatographic studies disclosed that HEP II appears to be a unique bone cell mitogen unlike any known growth factor, including the FGFs, IL-1s, and TNFs, EGF, IGF-I and -II, TGF-beta, beta 2 microglobulin, G-CSF, CSF-1 and GM-CSF. To characterize more fully the effects of the macrophage-derived monokines on osteoblast growth and function, clones were derived from calvaria explant cultures. Two clones, SDFRC-2.05 and SDFRC-3, were developed and found to exhibit osteoblastic characteristics, including high levels of alkaline phosphatase, synthesis of type I but not type III collagen, and an increased intracellular cAMP production in response to PTH. The SDFRC-3 cells exhibited a polygonal morphology like that of the explant-derived cells while SDFRC-2.05 cells exhibited a more fibroblastic morphology. When tested on the explant cultures and clones, HEP I and HEP II were found to stimulate DNA synthesis and increase protein per culture, but decreased alkaline phosphatase activity. Clone SDFRC-3 was found to be more responsive to HEP II than clone SDFRC-2.05. Both monokines were found to be more potent mitogens for bone cells than TGF-beta. HEP II, but not HEP I or TGF-beta, induced a transformation of bone cells from a polygonal to a fibroblastic morphology, suggesting the induction of migration prior to proliferation. Thus, macrophages may be responsible not only for bone repair but also for ensuring the linkage of bone formation to resorption during physiological remodeling. 相似文献