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51.
人毛乳头细胞凝集性生长差异表达基因cDNA文库的构建 总被引:4,自引:0,他引:4
目的 构建毛乳头细胞凝集性生长状态下差异表达基因的消减cDNA文库。方法 分别提取凝集性生长和非凝集性生长状态下毛乳头细胞中的总RNA,应用SMART cDNA合成技术和抑制性消减杂交技术分离毛乳头细胞凝集性生长状态下差异表达基因的cDNA片段并建立消减cDNA文库;利用PCR对随机挑选的100个白色菌落进行插入片段的验证,对其中证实有插入片段的30个克隆进行cDNA斑点杂交验证。结果 所构建的消减cDNA文库扩增后得到320个阳性克隆,随机挑选的100个阳性克隆中95%的均有长度在100—600bp的插入片段,cDNA斑点杂交验证显示27个(90.0%)克隆为阳性。结论 结合SMART cDNA合成技术,应用抑制性消减杂交成功地构建了毛乳头细胞凝集性生长差异表达基因消减cDNA文库,为进一步筛选和克隆毛乳头细胞凝集性生长相关基因奠定了基础。 相似文献
52.
自体皮源奇缺条件下瘢痕挛缩畸形的晚期临床修复 总被引:11,自引:6,他引:5
目的寻找对烧伤后畸形伴自体皮源奇缺患进行晚期修复的新方法。方法5例特重度、特大面积烧伤患治愈后伴较严重畸形,且自体皮源奇缺。采用柔软成熟的瘢痕皮肤作为修复的皮源,用扩张器扩张瘢痕皮肤后,切取中厚瘢痕皮片进行修复;不宜行瘢痕皮肤扩张术时,切取刃厚瘢痕皮片与异体脱细胞真皮基质组成复合皮进行修复。观察两种方法的疗效。结果所移植的扩张瘢痕皮片和复合皮均成活,功能和外形恢复良好,远期疗效近似正常自体中厚皮移植。结论采用不同厚度的瘢痕皮片修复烧伤畸形是可行的,可扩大自体皮源。此法对于皮源奇缺的瘢痕患尤其适用。 相似文献
53.
人表皮生长因子与碱性成纤维细胞生长因子纳米缓释剂对成纤维细胞的影响 总被引:3,自引:3,他引:0
目的:制备碱性成纤维细胞生长因子(bFGF)、人表皮生长因子(EGF)可降解缓释微球,考察其生物活性的保存情况,以及它们对成纤维细胞的作用。方法:采用改良的乳化冷凝法交联制备复合bFGF、EGF的明胶缓释微球,将它们加入成纤维细胞的培养液中,用细胞计数法、四甲基偶氮唑盐微量反应比色法(MTT法)测定细胞增殖情况。结果:复合bFGF、EGF的缓释微球平均粒径(11.32±3.64)μm;培养1天后各组细胞计数、吸光度(A)值差异均无显著性;5天后,两种生长因子缓释微球组细胞计数、吸光度(A)值明显高于对照组;7天后,两种生长因子缓释微球组值仍高于其它组,但差异无显著性。结论:复合bFGF、EGF的缓释微球制备工艺简便,成球性好;能较长时间地持续释放活性bFGF、EGF,可促进成纤维细胞的增殖。 相似文献
54.
Yoshito Matsui Tomoatsu Kimura Noriyuki Tsumaki Haruhiko Nakahara Nobuhito Araki Natsuo Yasui Takahiro Ochi 《Journal of orthopaedic science》1996,1(2):130-135
Recent DNA studies performed by several groups have detected mutations of the gene encoding fibroblast growth factor receptor
3 (FGFR3) in patients with achondroplasia-group disorders, including achondroplasia (ACH), hypochondroplasia (HCH), and thanatophoric
dysplasia (TD). For this study, we analyzed theFGFR3 gene in 31 Japanese patients with typical ACH, four with HCH, three with a condition intermediate between ACH and HCH (ACH/HCH-intermediate),
and one with TD. Of the 31 typical ACH patients, 29 showed a G1138 to A transition and the other two a G1138 to C transversion,
both resulting in a common Gly380Arg substitution in the transmembrane domain of FGFR3. The one TD and the four HCH patients
did not display any mutations in the transmembrane domain of FGFR3. Of the three ACH/HCH-intermediate cases, one patient showed
the Gly380Arg substitution and one did not, and further analysis of the second patient revealed the presence of Asn540Lys
substitution. The first patient was, therefore, genotypically diagnosed as ACH and the second as HCH. Peripheral blood leukocyte
DNA analysis in the remaining ACH/HCH-intermediate patient indicated an unequal ratio of mutant to normal PCR products, possibly
representing a somatic mosaic for the Gly380Arg mutation. Analysis of the common FGFR3 mutation thus appears to help in the
molecular diagnosis of patients with achondroplasia-group disorders. 相似文献
55.
A 9-month-old male infant had generalized diffuse blue-gray pigmentation over most of his body, sparing the scalp, face, neck, palms, soles, periumbilical area, genital area, and nipples. Within the lesion, there were several conspicuous macules of considerably darker hue. Histologic examination revealed numerous dermal melanocytes. By 16 months of age, the child's blue-gray pigmentation had decreased substantially. 相似文献
56.
目的 探究血清胰岛素样生长因子结合蛋白-3(IGFBP-3)、血小板来源生长因子(PDGF)及碱性成纤维细胞生长因子(bFGF)联合检测对多囊卵巢综合征(PCOS)患者妊娠结局的预测价值。方法 选取2021年5月—2022年12月在沧州市中心医院接受治疗的150例PCOS孕妇作为PCOS组,另选取同期在该院产检健康的90例孕妇作为对照组。比较两组血清IGFBP-3、PDGF及bFGF水平;根据PCOS组孕妇的妊娠情况分为妊娠结局良好组119例和妊娠结局不良组31例,统计PCOS患者妊娠结局情况并比较血清IGFBP-3、PDGF、bFGF水平;绘制受试者工作特征(ROC)曲线分析血清IGFBP-3、PDGF和bFGF对PCOS的预测价值。结果 PCOS组血清IGFBP-3水平低于对照组(P <0.05),PDGF、bFGF水平均高于对照组(P <0.05)。妊娠结局不良组血清IGFBP-3水平低于妊娠结局良好组(P <0.05),PDGF、bFGF水平均高于妊娠结局良好组(P <0.05)。ROC曲线分析结果显示,血清IGFBP-3、PDGF、bFGF水平预测PC... 相似文献
57.
Chien Yie W. Chien Te-yen Bagdon Robert E. Huang Yih C. Bierman Robert H. 《Pharmaceutical research》1989,6(12):1000-1010
Several transdermal contraceptive device (TCD) formulations were developed to provide a dual-controlled transdermal delivery of levonorgestrel (LN), a potent progestin, and 17-estradiol (E2), a natural estrogen. Using a sensitive HPLC method, the in vitro release and skin permeation profiles of LN and E2 from various TCD formulations were simultaneously characterized in the hydrodynamically well-calibrated Valia–Chien skin permeation cells and both were found to follow zero-order kinetics. The rates of drug release and skin permeation were observed to vary significantly depending upon some formulation parameters. Six-month stability studies were performed on seven formulations at room and elevated temperatures (37 and 45°C), and two (Formulations 4 and 5) were found to be acceptable, based on drug recovery, release rate, and skin permeation rate data. Judging from the 6-month accelerated stability studies, it is projected these two formulations will have shelf-life of at least 2 years. As a result of development of an efficient manufacturing process, Formulation 4 was selected for further evaluation. One-week primary skin irritation evaluation in 6 rabbits indicated that Formulation 4 is nonirritating, and it was thus selected for Phase I clinical bioavailability/dose proportionality studies in 12 healthy female volunteers of child-bearing age. Results of pharmacokinetic and pharmacodynamic analyses demonstrated that it is capable of achieving and maintaining a steady-state serum level of LN throughout the 3-week treatment period by weekly applications of one or two TCD patches (10 or 20 cm2). A dose proportionality was obtained in the serum drug levels, daily dose delivered, and contraception efficacy. An excellent correlation was obtained for the rates of transdermal delivery determined by the in vitro studies using human cadaver skin, the in vivo studies in rabbits, and the clinical studies in living subjects. 相似文献
58.
Wen FQ Kohyama T Sköld CM Zhu YK Liu X Romberger DJ Stoner J Rennard SI 《Inflammation》2002,26(6):279-290
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun. 相似文献
59.
G. Chadi A. M?er L. Rosen A. M. Janson L. A. Agnati M. Goldstein S.-O. ?gren R. F. Pettersson K. Fuxe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(1):145-158
Basic fibroblast growth factor (bFGF, FGF-2) is a trophic factor for neurons and astrocytes and has recently been demonstrated in the vast majority of dopamine (DA) neurons of the ventral midbrain of the rat. Potential neuroprotective actions of FGF-2 in the l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model have also been reported. The actions of the FGF-2 have now been further analyzed in a combined morphological and behavioural analysis in the MPTP model of the adult black mouse, using a continuous human recombinant FGF-2 (hrFGF-2) intraventricular (i.v.t.) administration in a heparin-containing (10 IU heparin/ml) mock cerebrospinal fluid (CSF) solution. Tyrosine hydroxylase (TH) immunocytochemistry in combination with computer assisted microdensitometry demonstrated a counteraction of the MPTP-induced disappearance of neostriatal TH-immunoreactive (ir) nerve terminals following the FGF-2 treatment. Unbiased estimates of the total number of nigral TH ir neurons, using stereological methods involving the optical disector (Olympus), showed that the MPTP-induced reduction in the number of nigral TH ir nerve cell bodies counterstained with cresyl violet (CV; by 56%) was partially counteracted by the FGF-2 treatment (by 26%). The behavioral analysis demonstrated an almost full recovery of the MPTP-induced reduction of the locomotor activity after FGF-2 treatment. This action was maintained also 1 week after cessation of treatment. The hrFGF-2 produced an astroglial reaction as determined in the lateral neostriatum and in the substantia nigra (SN) far from the site of the infusion, indicating that the growth factor may have reached these regions by diffusion to activate the astroglia. Immunocytochemistry revealed FGF-2 immunoreactivity (IR) in the nuclei of the astroglia cell population in the dorsomedial striatum and the microdensitometric and morphometric evaluation demonstrated an increase in the number, but not in the intensity, of these profiles on the cannulated side, suggesting the possibility that hrFGF-2 stimulates FGF-2 synthesis in astroglial cells with low endogenous FGF-2 IR. These results indicate that hrFGF-2, directly and/or indirectly via astroglia, upon i.v.t. infusion exerts trophic effects on the nigrostriatal DA system and may increase survival of nigrostriatal DA nerve cells exposed to the MPTP neurotoxin. 相似文献
60.
目的:为临床研究提供形态学资料。方法:用免疫组化方法,观察碱性成纤维细胞生长因子(bFGF)在糖尿病小鼠视网膜的分布及表达密度;用透射电镜观察不同病程视网膜细胞的损害情况。结果:糖尿病及正常小鼠视网膜各层细胞均表达bFGF,反应强度和密度不同。发病组自6月龄起,居于大血管周围的阳性节细胞密度增加;不同病程bFGF的表达有不同程度的增加。随糖尿病病程延长,细胞超微结构受到不同程度的损害。结论:糖尿病时增多的bFGF直接或间接作用于血管内皮细胞和平滑肌细胞,刺激二者增殖,促进微血管病变的发生;另一方面,减弱视细胞与双极细胞间的信息传递,对糖尿病性盲的发生起重要作用。同时,各种细胞的超微结构及相应的功能也受到不同程度的损害。 相似文献