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33.
血管紧张素对增生性瘢痕成纤维细胞纤维连接蛋白合成的影响 总被引:1,自引:1,他引:0
目的:探讨血管紧张素Ⅱ(AngⅡ)及其Ⅰ型、Ⅱ型受体阻断剂和钙调神经磷酸激酶(CaN)的阻滞利环胞素A(CsA)对增生性瘢痕来源的成纤维细胞纤维连接蛋白mRNA和蛋白表达的作用。方法:体外分离培养增生性瘢痕成纤维细胞,分别将一定浓度的AngⅡ(10^-9~10^-5mmol/L),和AngⅡ10^-6mmol/L加上不同阻滞剂losartan、PD123319、环胞素A(浓度均为10^-5mmol/L)加入细胞培养液中刺激48h,分别采用逆转录聚合酶链反应(RT—PCR)及Westernblot印迹方法检测增生性瘢痕成纤维细胞纤维连接蛋白(FN)的mRNA及蛋白表达。结果:体外成功地培养增生性瘢痕成纤维细胞。经AngⅡ刺激48h后,FN mRNA和蛋白表达量明显增高,增高程度与AngⅡ浓度呈正比;加入losaartan和环胞素A后,FN原mRNA和蛋白表达量较单用AngⅡ组下降,而加入PD123319后,FNmRNA和蛋白表达量较单用AngⅡ组无明显改变。结论:AngⅡ可促增生性瘢痕成纤维细胞的FN合成,可能在增生性瘢痕的发展过程中起重要作用,该作用主要通过AngⅡ的Ⅰ型受体介导完成,该作用可能与CaN信号通路有关。 相似文献
34.
目的:研究安氏II类错畸形对青春期面部骨轮廓发育的影响。方法:收集安氏II类错畸形的成人患者和青少年患者共362例。摄取头颅定位侧位片及头颅定位正位片。对面高、面宽等19项测量项目做比较分析及t检验。结果:①安氏II类青少年患者与正常青少年相比,下颌基骨长度、下颌长度较小,但无统计学差异。②安氏II类成年患者与正常成年人相比,下颌基骨长度、下颌长度有显著性差异。③安氏II类患者下颌骨在青春发育期有向前、向上旋转的趋势。结论:安氏II类错畸形患者经过青春期发育,使面部畸形程度更加严重。本研究得出安氏II类错畸形对青春期面部骨轮廓发育的影响,对正颌外科和正畸治疗具有参考意义。 相似文献
35.
Gene expression regulation and cancer 总被引:1,自引:0,他引:1
36.
Because of the lack of organs for heart transplantations, left ventricular assist devices (LVADs) have become more and more important during the last few years. They are used for both bridging the time until transplantation as well as destination therapy for patients who are not able or willing to undergo a heart transplantation. Forensic and clinical pathologists will increasingly be confronted with fatalities of patients with LVADs. Beside natural causes of death and typical unavoidable complications, technical problems and user errors must be resolved. Under certain circumstances a suicidal or homicidal manner of death by manipulation of the device also has to be considered. 相似文献
37.
Hossam B El-Zawawy Corey S Gill Rick W Wright Linda J Sandell 《Journal of orthopaedic research》2006,24(12):2150-2158
Smoking delays the healing process and increases morbidity associated with many common musculoskeletal disorders, including long bone fracture. In the current study, a murine model of tibial fracture healing was used to test the hypothesis that smoking delays chondrogenesis after fracture. Mice were divided into two groups, a nonsmoking control group and a group exposed to cigarette smoke for 1 month prior to surgical tibial fracture. Mice were euthanized at 7, 14, and 28 days after surgery. The outcomes measured were immunohistochemical staining for type II collagen protein expression as a marker of cartilage matrix and proliferating cell nuclear antigen (PCNA) staining to measure proliferation at the site of injury. Toluidine blue staining and histomorphometry were used to quantify areas of cartilaginous and noncartilaginous fracture callus. Radiographs were analyzed for evidence of remodeling after injury. At day 7 after injury, mice exposed to cigarette smoke had a smaller fracture callus with less cartilage matrix compared to controls. Proliferation was present at high levels in both groups at this time point, but proliferating cells had a more immature morphology in the smoking group. At day 14, chondrogenesis was more active in smokers compared to controls, while a higher percentage of bone was present in the control animals. At day 28, X-ray analysis revealed a larger fracture callus remaining in the smoking animals. Together, these findings show that the chondrogenic phase of tibial fracture healing is delayed by smoking. This study represents, to our knowledge, the first analysis of molecular and cellular mechanisms of healing in a smoking mouse fracture model. 相似文献
38.
口外弓配合唇档远移磨牙的临床研究 总被引:1,自引:1,他引:0
目的:研究口外弓配合唇档远移磨牙的临床应用及其疗效。方法:选择15例恒牙早期上颌轻度牙性前突或轻、中度拥挤的安氏II类患者,应用口外弓配合唇档,通过X线头影测量观察其上颌磨牙及前牙治疗前后变化情况。结果:应用口外弓配合唇档推磨牙向远中3~6个月后,II类咬合关系恢复至安氏I类关系。上颌第一磨牙向远中平均移动4.14mm,上颌中切牙向唇侧移动0.66mm。结论:只要病例选择合适,方法运用得当,口外弓配合唇档就能获得较满意的远移磨牙的疗效。 相似文献
39.
Natural history of extensive Mongolian spots in mucopolysaccharidosis type II (Hunter syndrome): a survey among 52 Japanese patients 总被引:1,自引:0,他引:1
T Ochiai† Y Suzuki‡ T Kato‡ H Shichino§ M Chin§ H Mugishima§ T Orii¶ 《Journal of the European Academy of Dermatology and Venereology》2007,21(8):1082-1085
BACKGROUND: Recent reports have shown a correlation between extensive Mongolian spots and mucopolysaccharidosis type II (Hunter syndrome). However, a statistical survey of the incidence and natural history of extensive Mongolian spots among the patients with Hunter syndrome is lacking. OBJECTIVES: To determine the prevalence of extensive Mongolian spots, to determine the natural course of the spots according to age in Japanese patients with Hunter syndrome, and to compare them with the results obtained from the patients' brothers who did not have Hunter syndrome. PATIENTS/METHODS: Fifty-two males with Hunter syndrome aged 3 to 40 years were studied. Twenty-five patients were examined in two clinics to determine the existence and characteristics of the spots. We interviewed their families about the spots in their neonates and the natural course of the spots according to their ages. The same survey was done among another 27 patients using a mailed questionnaire to their families. As control, we investigated 21 brothers of the patients by a mailed questionnaire to their families. RESULTS: The extensive Mongolian spots are identified in almost all the infants with Hunter syndrome and disappear extremely later in their life. The lesions had a high incidence of deep-blue hyperpigmentation. Regardless of age, the overall incidence was 78%. All of the brothers who did not have Hunter syndrome had common-type Mongolian spots in neonates, which regressed during their childhood. CONCLUSION: Our results confirm a strong correlation between extensive Mongolian spots and Hunter syndrome for the Japanese population. The presence of extensive Mongolian blue spots should alert the physician to the possibility of Hunter syndrome. 相似文献
40.
Novel polyanionic proteins were designed to increase the rate of heparin cofactor II (HC) inhibition of α-thrombin, an essential protease in the coagulation cascade. Two α-helical coiled-coil proteins, a 62-residue dimer containing 8 Glu residues (E8C) and a 104-residue dimer containing 14 Glu residues (E14C), plus two 31-residue control peptides containing 8 Glu residues each (E8A and E8B), were chemically synthesized, structurally characterized and enzymatically assayed. Circular dichroic spectrophotometry indicated that both E8C and E14C formed stable two-chain α-helical coiled coils at pH 7 and 25 °C. The control peptides were only partially α-helical. E14C remained folded at 90 °C but E8C was half unfolded at 49 °C. Coiled-coil proteins E8C and E14C maximally accelerated by 35- and 33-fold, respectively, the rate of HC inhibition of α-thrombin. None of these compounds accelerated antithrombin inhibition of α-thrombin, and neither control peptide accelerated HC inhibition of α-thrombin. Acceleration of the HC inhibition of α-thrombin showed bimodal dependence on the concentration of the polyanionic protein, which is consistent with formation of a HC-coiled-coil-thrombin ternary complex. The results suggest that antithrombotic polyanionic α-helical coiled-coil proteins can be designed and synthesized and that the occurrence of secondary structure can be correlated with biologcal activity. © Munksgaard 1995. 相似文献