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61.
大鼠脂肪间充质干细胞的成骨分化   总被引:2,自引:2,他引:2  
目的:观察大鼠脂肪间充质干细胞经成骨诱导向成骨细胞分化的生物学特性,探讨其作为骨组织工程种子细胞的可行性。方法:实验于2004-07/2006-03在中南大学湘雅医院中心实验室完成主要工作。①取健康SD大鼠双侧腹股沟区脂肪垫,消化法分离出脂肪间充质干细胞,接种入含有体积分数为0.1的新生牛血清的低糖DMEM培养基进行原代培养。②取第3代的脂肪间充质干细胞,用含有体积分数为0.1的新生牛血清、0.1μmol/L地塞米松、50μmol/L抗坏血酸、10mmol/Lβ-甘油磷酸钠的高糖DMEM培养基诱导其向成骨细胞分化。③于3,5,7,10,12,14,21d分别采用倒置显微镜观察细胞形态及增殖情况、Gomori改良钙钴法碱性磷酸酶染色、茜素红S钙结节染色和Ⅰ型胶原免疫细胞化学染色检测脂肪间充质干细胞成骨分化的情况。结果:①脂肪间充质干细胞原代细胞呈成纤维细胞样长梭形外观,传代稳定,细胞形态均一。②经成骨诱导,脂肪间充质干细胞体积增大,呈多角形;成骨诱导14d,Gomori改良钙钴法碱性磷酸酶染色,细胞胞浆内可见浅棕色至棕黑色的颗粒,平均染色阳性率为80%;碱性磷酸酶活性随时间的延长而逐渐增高[3,5,7,10,12,14d依次为(2.43±0.09),(3.60±0.08),(5.01±0.09),(7.75±0.07),(9.59±0.09),(10.94±0.10)μkat/L];成骨诱导21d,钙结节形成明显,茜素红S染色,呈红色结节;成骨诱导7d,Ⅰ型胶原免疫细胞化学染色,细胞胞浆呈棕黄色,胞核经苏木精复染为蓝色。结论:大鼠脂肪间充质干细胞经成骨诱导具有成骨细胞的生物学特性,可作为骨组织工程的种子细胞。  相似文献   
62.
目的 探讨成人胆管囊肿及其合并症的超声、核磁及胰胆管水成像 (MR/ MRCP)的影像表现。方法 选取胆管扩张病例进行超声及核磁检查 ,观察胆胰管内径、胆管扩张形态、管壁厚度、回声 ,并进行彩色多普勒血流检测及核磁胰胆管水成像 (MR/ MRCP)检查 ,两者结果与术后病理对照。结果 经手术证实胆管囊肿 2 0例 ,包括 :Caroli's病 2例 , 型胆总管囊肿 14例 ,呈囊性、梭形、圆柱形扩张 ;肝门部胆管囊肿 (囊肿型 ) 3例 ,胆总管上段憩室 1例 ( 型 )。合并胆囊结石 10例 ,肝内胆管、胆总管结石 8例 ;合并肝局灶性炎 3例 ,肝脓肿 1例 ;合并癌变 5例 (高、低分化腺癌 3例 ,黏液腺癌 1例 ,类癌 1例 ) ;共同管过长 (>1.5 cm) 6例。超声与 MRCP对胆管囊肿全部诊断。合并症中超声对炎变、结石、癌变诊断分别为 95 % ,10 0 % ,95 % ,而 MRCP/MR为 10 0 % ,90 % ,95 %。超声对结石、癌变及管壁的微细结构观察优于 MRCP,MRCP对胆管全程显示优于超声 ,结合平扫及增强扫描诊断炎变符合率 10 0 %。结论 超声与 MR成像在成人胆管囊肿及其合并症中的诊断意义重大 ,联合应用有利于对该病的全面认识 ,便于指导临床。  相似文献   
63.
Lack of clinical significance of "enzyme-only" red cell alloantibodies   总被引:1,自引:0,他引:1  
In a retrospective study on samples from 10,000 recently transfused patients, 35 samples were found to contain an antibody that reacted with ficin-treated red cells but was not demonstrable by low-ionic- strength saline solution and indirect antiglobulin test (LISS-IAT). In those 35 patients, the specificity of the antibody was such that each patient would have been transfused with antigen-negative blood had the antibody reacted in LISS-IAT. Tests on red cells from the units already transfused showed that 19 patients had among them received, by chance, 32 antigen-positive and 74 antigen-negative units. The remaining 16 patients had among them received 57 units that were, again by chance, all antigen negative. One patient given antigen-positive blood suffered a delayed transfusion reaction; in two others the antibodies became LISS-IAT active after transfusion. However, similar changes to the LISS- IAT-active state were seen with two antibodies of patients given only antigen-negative blood. Also found in the 10,000 patients were 28 clinically insignificant antibodies, 77 sera in which the antibody was too weak to identify, and 216 autoantibodies that reacted only with ficin-treated red cells. These data support a belief, generally held in the United States but not necessarily elsewhere, that the use of protease-treated red cells for routine pretransfusion tests creates far more work than the accrued benefits justify.  相似文献   
64.
The effects of neurotensin on mudpuppy retinal cells were studied using extracellular and intracellular electrophysiological recording techniques and bath application of the peptide. Ganglion and amacrine cells (but not bipolar or horizontal cells) were reversibly depolarized by low micromolar concentrations of neurotensin. Depolarizations also occurred with neurotensin application during cobalt block of synaptic transmission and were accompanied by decreased input resistances. This suggests neurotensin may act directly on amacrine and ganglion cells as a conventional excitatory transmitter. However, in many retinas, cells responded to light stimuli and to other drugs but not to neurotensin. These negative results are important in considering the peptide's normal role in retinal function.  相似文献   
65.
66.
Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis.  相似文献   
67.
The case of a 70-year-old white man with a 10-year history of penile lichen sclerosus (LS) who developed microinvasive squamous cell carcinoma on LS is described. A high incidence of penile cancer arising on genital LS has recently been observed. The authors stress the importance of an adequate diagnosis and long-term follow-up in patients with penile LS because of the malignant potential of the disease.  相似文献   
68.
As the current antipsoriatic medications are commonly associated with deleterious side-effects, a determined search for safer agents, which could be used alone or in combination with current antipsoriatic drugs, would be very imperative. Psoriasis is believed to be characterized by a type 1 cytokine pattern; interferon-gamma, interleukin (IL)-2 and tumour necrosis factor (TNF)-alpha are predominantly expressed in this disorder. Nitric oxide, reactive oxygen species, histamine, leukotriene B4, and decreased [corrected] keratinocyte cyclic adenosine monophosphate/cyclic guanosine monophosphate (cAMP/cGMP) ratio are supposed to play roles in the pathogenesis of this disorder. Based on the immunopathogenesis of psoriasis, this paper introduces three novel, potential treatments for this clinical conundrum: (i) cannabinoids, which exert inhibitory effects on antigen processing and macrophage/T-cell interaction and also on the release of IL-2, TNF-alpha and nitric oxide from immune cells; (ii) loratadine, which is an antihistamine capable of increasing [corrected] the cAMP/cGMP ratio and the production of leukotriene B4; and (iii) allopurinol, which scavenges free radicals, inhibits the production of TNF-alpha, and downregulates the expression of intercellular adhesion molecule-1 and P2X7 receptors on monocytes/macrophages, which are involved in antigen presentation and production of the inflammatory response, respectively. Importantly, allopurinol, especially in combination with cyclosporin, has been shown to be effective against experimental autoimmune uveitis, which, like psoriasis, is a cell-mediated autoimmune disorder.  相似文献   
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