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61.
瘢痕疙瘩家系Fas基因的突变:2个家系10份标本分析   总被引:1,自引:0,他引:1  
目的:观察瘢痕疙瘩家系样本中Fas基因有无突变,探讨Fas基因突变在瘢痕疙瘩形成中的意义。方法:实验于2005-01/05在上海基康公司完成。①标本来自南方医科大学南方医院整形外科2005年收集的A和B两个瘢痕疙瘩家系,所有参与观察的家系成员均签署知情同意书。②采用聚合酶链反应及基因测序技术,分别以A家系两例患者的瘢痕疙瘩组织为观察对象,以其周围正常皮肤及外周静脉血作为自身对照;其配偶的外周静脉血作为正常对照。并以B家系中两例患者的外周静脉血作为不同家系间的对照。共取10份样本,4份组织样本,6份静脉血标本。检测10份样本中Fas基因外显子1~9的基因序列。结果:①基因测序发现所检测的10个瘢痕疙瘩家系标本Fas基因的1~8外显子均未发现突变。②2份瘢痕疙瘩组织标本在第9外显子编码区的11bp,53bp两个位点上存在单个碱基的基因突变或多态性改变。结论:瘢痕疙瘩Fas基因外显子9区段的基因结构异常极有可能造成Fas蛋白的功能改变,从而导致身体局部瘢痕疙瘩的形成。  相似文献   
62.
目的:已有研究证实,活血化瘀中药可对抗激素的作用,对激素性股骨头缺血性坏死早期有明显的防治作用。观察桃红四物汤对激素性股骨头缺血性坏死碱性成纤维细胞生长因子表达的影响,进一步阐明活血化瘀法防治激素性股骨头缺血性坏死的机制。方法:实验于2005-04/2006-10在福建中医学院中心实验室完成。①实验材料:健康成年新西兰大白兔60只,雌雄各半,体质量1.8~2.2kg,清洁级,由福建中医学院实验动物中心购自上海市松江区松联实验动物场。桃红四物汤的组成成分为:桃仁、红花、熟地、当归、白芍、川芎。②实验方法:60只健康成年新西兰大白兔,随机分为正常组6只和实验组54只。实验组采用贺氏造模法建立股骨头缺血坏死模型,6周后处死正常组和实验组各6只,确定造模成功。将造模剩余动物随机分为中药治疗组和激素对照组,每组21只:中药治疗组以桃红四物汤7mL/kg(浓度为0.75g/mL)灌胃治疗,1次/d,激素对照组以生理盐水7mL/kg灌胃治疗,1次/d。③实验评估:于治疗后1,2,4周进行股骨头组织病理学观察,并采用放射免疫法检测血清碱性成纤维细胞生长因子含量变化。结果:纳入新西兰大白兔60只,实验过程中因心脏、脑血管梗死死亡18只,进入结果分析42只。桃红四物汤灌胃治疗1,2,4周后,中药治疗组股骨头局部空骨陷窝数明显减少,与激素对照组比较,差异有显著性意义(P<0.05),中药治疗组碱性成纤维细胞生长因子表达增强,与激素对照组相比,差异有显著性意义(P<0.01)。结论:桃红四物汤能促进激素性股骨头缺血性坏死模型兔体内碱性成纤维细胞生长因子的表达,明显减少股骨头局部空骨陷窝数,促进坏死股骨头的修复,这可能是活血化瘀法防治激素性股骨头缺血性坏死的机制之一。  相似文献   
63.

Background and purpose:

Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery.

Experimental approach:

The cytosolic Ca2+ concentrations ([Ca2+]i), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery.

Key results:

Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR1) antagonist, while it was mimicked by PAR1-activating peptide (PAR1AP), but not PAR4AP. The thrombin-induced contraction was associated with a small elevation of [Ca2+]i and an increase in MLC20 phosphorylation. Thrombin and PAR1AP induced a greater increase in tension for a given [Ca2+]i elevation than that obtained with high K+-depolarization. They also induced a contraction at a fixed Ca2+ concentration in α-toxin-permeabilized preparations.

Conclusions and implications:

The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR1 and thereby increasing the sensitivity of the myofilament to Ca2+. This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH.  相似文献   
64.
人参叶中微量新皂甙-La的分离与鉴定   总被引:4,自引:0,他引:4  
前已报道从人参(Panax ginseng C.A.Meyer)叶中分到三种微量新皂甙。在继续研究的基础上,又得到一个微量新皂甙,命名为人参皂甙-La(ginsenoside-La)。人参皂甙-La,无色针晶(MeOH),[α]D~(20)—18.4(Pyridine-d_5)。负离子FAB-MS  相似文献   
65.
Lozzio  BB; Machado  EA; Mitchell  J; Lozzio  CB; Wust  CJ; Golde  DW 《Blood》1983,61(6):1045-1053
Six human hematopoetic cell lines were successfully heterotransplanted into athymic (nude) and asplenic-athymic (lasat) neonatal mice. The tumors arising from leukemia and lymphoma cells could then be serially transplanted into adult nude mice. Seven days after the fourth serial mouse passage, each mouse was treated with goat immune gamma globulin against K-562 cells. One control group was treated similarly, but with nonimmune (normal) gamma globulin, while another control group was not treated. The goat gamma globulin was not toxic for nude and lasat mice, and the immune, but not the normal, gamma globulin suppressed local subcutaneous growth of myelosarcomas, lymphosarcomas, and Burkitt lymphoma cells. On the other hand, the growth of lung, breast, and prostatic carcinomas and a melanoma of human origin were not altered by the immune gamma globulin. Since suppression of cell growth occurred equally well in decomplemented mice, a complement-mediated cytotoxicity apparently cannot be considered as responsible for the abrogation. The Fab fragment of the immunoglobulin did not suppress the growth of the myelosarcomas. We conclude that antibody suppression of the in vivo proliferation was specific for malignant hematopoietic cells and that the Fc portion of IgG is necessary for in vivo cytolysis of leukemia cells. The most probable mechanisms are direct antibody cytolysis and antibody-dependent macrophage-mediated cytotoxicity.  相似文献   
66.
67.
Die anthroposophische Misteltherapie kann etablierte onkologische Standardtherapien im Sinne einer umfassenderen und ganzheitlichen Versorgung erg?nzen.  相似文献   
68.
Chemokines are involved in the control of dendritic cell (DC) trafficking, which is critical for the immune response, namely in allergic contact dermatitis (ACD). In this work, we investigated by flow cytometry the effect of the contact sensitizers 2,4-dinitrofluorobenzene (DNFB), 1,4-phenylenediamine (PPD) and nickel sulfate (NiSO4), on the surface expression of the chemokine receptors CCR6 and CXCR4 in DC. As an experimental model of a DC we used a fetal skin-derived dendritic cell line (FSDC), which has morphological, phenotypical and functional characteristics of skin DC. Our results show that all the skin sensitizers studied decreased the membrane expression of the chemokine receptors CCR6 and CXCR4. In contrast, 2,4-dichloronitrobenzene (DCNB), the inactive analogue of DNFB without contact sensitizing properties, was without effect on the surface expression of these receptors. Lipopolysaccharide (LPS), which induces the maturation of DC, also reduced surface CCR6 and CXCR4 expression.  相似文献   
69.
Purpose : To report eight patients with diagnosed systemic lupus erythematosus (SLE) who presented with a variety of neuro‐ophthalmological complications and outcomes. Methods : A review of the follow up, subsequent management and outcomes of the neuro‐ophthalmological complications of eight patients with SLE. Results : The patients presented with a myriad of symptoms of varying severities. The most common manifestations were that of optic neuropathy and eye movement abnormalities. The outcome was variable ranging from complete recovery to optic atrophy with navigational visual acuity. Treatment was often empirical, although early treatment with corticosteroids has been tried with varying success. Conclusions : The pathophysiology in the neuro‐ ophthalmological manifestations of SLE is thought be due to vaso‐occlusive disease of the small vessels of the nerve and brain, secondary to an autoimmune process. Ophthalmologists may need to consider the diagnosis of SLE in young women who present with a recent onset of neuro‐ophthalmological symptoms and signs.  相似文献   
70.
Aim : To determine what New Zealand ophthalmologists, general practitioners and optometrists consider important ophthalmic topic areas requiring emphasis in the medical undergraduate curriculum. Method : A total of 793 questionnaires related to the content and teaching of undergraduate ophthalmology were sent to ophthalmologists, general practitioners and optometrists. Results were analysed separately for the three respondent groups and as a whole. Results : Four hundred and fourteen questionnaires were returned (52% return rate). Overall responses of the three participant groups were similar and agreed favourably with the current curriculum. The ability to measure visual acuity (97%) and pupillary reflexes (93%), perform ophthalmoscopy (92%), and assess visual fields (68%) were regarded as ‘important or essential’ by the majority of respondents. Only 53% of respondents consider the ability to diagnose chronic open angle glaucoma as important. The respondents stressed the importance of the diagnosis of predominantly anterior segment disease contrasting with the traditional bias towards the teaching of ophthalmoscopy and posterior segment disease. The majority of respondents stressed the importance of graduating medical students being able to treat bacterial and allergic conjunctivitis, styes, blepharitis, corneal abrasion, and corneal and conjunctival foreign bodies, areas present but not normally emphasized in current curricula. Conclusion : The findings of this study provided additional data to facilitate curriculum design and illustrated the value of an integrated problem‐based learning approach in ophthalmology undergraduate teaching.  相似文献   
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