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31.
子宫内膜异位症患者血清TNF-α和TNF-β的测定   总被引:7,自引:1,他引:6  
目的:了解子宫内膜异位症(简称内异症)患者血清中肿瘤坏死因子-α(TNF-α)和肿瘤坏死因子-β(TNF-β)的水平以及在腹腔镜保守性手术治疗前后的变化。方法:采用酶联免疫吸附法检测82例内异症患者(内异症组)和68例非内异症妇女(对照组)血清中TNF-α和TNF-β的含量及49例手术前后两者水平的变化。结果:内异症组血清TNF-α和TNF-β含量均显著高于对照组(P<0.01),且二者表达量随病情加重有上升趋势(P<0.05)。手术后Ⅲ~Ⅳ期患者血清中的TNF-α和Ⅰ~Ⅳ期患者血清TNF-β的含量随着内异灶的清除逐渐下降。结论:检测患者血清中TNF-α和TNF-β的含量,对术后随访、监测及手术效果的评价具有重要意义。  相似文献   
32.
目的:探讨细胞活素肿瘤坏死因子-α(TNF-α)、SNAP(S-Nitroso-Nacetyl-penicillamine)对胰腺癌细胞产生血管内皮生长因子A、C(VEGF-A、C)的调节.方法:用Northern杂交和Western杂交法分析6种人胰腺癌细胞株中VEGF-A、C基因和蛋白的表达;以TNF-α或SNAP刺激其中两个细胞株后用逆转录-聚合酶链式反应技术(RT-PCR)分析其VEGF-A、C基因的表达.结果:Northern杂交法显示这6种胰腺癌细胞株均有4.1kb VEGF-A基因和2.4kb VEGF-C基因的表达;Western杂交法显示它们均有分子量为43kD的VEGF-A蛋白质和分子量为55kD的VEGF-C蛋白质的表达.RT-PCR分析法显示:TNF-α使细胞株COLO-357产生VEGF-A、VEGF-C mRNA分别减少约1~2.5倍、1~2倍,使细胞株CAPAN-1产生VEGF-A、VEGF-C mRNA分别减少约1倍、1.6~2.5倍;而SNAP刺激细胞株COLO-357产生VEGF-A mRNA增加约5倍,刺激细胞株CAPAN-1产生VEGF-A mRNA增加约4倍,但对这两种细胞株产生VEGF-C mRNA均无明显刺激作用.结论:细胞活素TNF-α和低氧通过调节血管内皮生长因子A、C的表达而影响胰腺癌细胞的生物学特性,抑制癌细胞的增殖,促进其凋亡、死亡或进展、恶化.  相似文献   
33.
Human tumor–infiltrating lymphocytes (TILs) derived from pleural or ascitic fluid were incubated with recombinant interleukin 2 and transfected with human tumor necrosis factor (TNF) a gene by the lipofection procedure. The resulting TILs secreted significant amounts of TNF in the culture supernatant and exhibited cytotoxicity against established cell lines, such as K562 and Daudi, and autologous tumor cells. The TNF gene–transfected TILs exhibited an augmented killing of autologous tumor cells.  相似文献   
34.
Summary Tumor necrosis factor α (10−10–10−8M) had no effects on cyclic AMP production by the osteoblastic osteosarcomal cells, Saos-2 and G292, or normal rat calvarial cells. The cytokine did, however, inhibit the parathyroid hormone (PTH)-induced effect on cyclic AMP in the Saos-2 and normal rat osteoblastic cells. This inhibitory effect did not occur on prostaglandin E2-induced cyclic AMP increases in the osteoblastic cells. Interleukin-1 (10 U/ml −100 U/ml) did not produce any effect on basal levels or PTH-induced cyclic AMP increases in these cells.  相似文献   
35.
Arsenical necrosis of the jaws   总被引:3,自引:0,他引:3  
After a brief historical review of the use of arsenic in dental practice two cases of arsenical necrosis of the jaws, affecting the maxilla and mandible respectively, are reported. Both patients were treated conservatively over an extended period with excellent results. It is concluded that there is no justification, whatsoever, for the use of arsenic in modern dental practice and that, although prolonged, conservative treatment of chemical necrosis of the jaws is preferable to more radical treatment.  相似文献   
36.
急性脑梗塞患者血清肿瘤坏死因子水平变化的观察   总被引:7,自引:0,他引:7  
采用双抗体夹心ELISA法对30例正常对照和36例急性脑梗塞患者血清肿瘤坏死因子(TNF)水平进行了检测。结果显示:急性脑梗塞组血清TNF水平显著高于正常对照组,血清TNF水平变化与脑梗塞容积大小密切相关,恢复期血清TNF水平显著降低。结果提示,TNF参与了脑梗塞发生后病理变化过程,检测血清TNF对判定脑梗塞容积大小有一定的临床意义。  相似文献   
37.
Conclusion The mechanisms that regulate regeneration of kidney epithelial cells after acute tubular necrosis are poorly understood. Repair of the nephron can take place in the adverse systemic metabolic setting caused by failure of renal function. This clinical observation suggests that factors released at the site of the tubular insult can mediate repair. Studies carried out in this and other laboratories show that kidney epithelial cells can release and respond to polypeptide growth factors which may thereby contribute to renal regeneration by autocrine and paracrine mechanisms. Specific growth factors secreted by cells and deposited in the tubular basement membrane prior to injury may subsequently participate in nephron repair. In addition, adenine nucleotides released from injured or dying cells at the injury site or provided exogenously could stimulate surviving renal epithelial cells at the edges of the wound to migrate along the basement membrane to rapidly reepithelialize the nephron and subsequently initiate mitogenesis to replace cells lost by necrosis.The nephrotoxic effect of many agents used in cancer chemotherapy and the older age of patients undergoing complicated surgical procedures has increased the incidence of ARF, whereas the mortality rate has not changed since the early 1950s [22]. Thus there is considerable need for innovative therapeutic strategies. An important goal of future research efforts is to identify new growth factors that facilitate migration, differentiation, and proliferation of renal epithelial cells at sites of tubular necrosis. Isolation and use of these agents in combination with dialysis and nutritional support could speed renal regeneration and thereby improve the outcome in patients with this condition.Abbreviations ARF acute renal failure - ECM extracellular matrix - EGF epidermal growth factor - FGF fibroblast growth factor - IGF insulin-like growth factor - MGSA melanocyte growth-stimulating activity - PDGF platelet-derived growth factor - IGF transforming growth factor  相似文献   
38.
收集小鼠腹腔巨噬细胞,调整细胞浓度为5×10 ̄5/ml,加入24孔培养板每孔1ml,内毒素刺激前后不同时间加入白藜芦醇甙培养,检测上清中肿瘤坏死因子,溶酶体酶(N-乙酰-β-D氨基葡萄糖苷酶NAG)的变化,结果说明:白藜芦醇甙可减少上清中TNF_α和NAG的量,通过此可减少内毒素刺激产生的由TNF_α和NAG介导的组织损伤。  相似文献   
39.
1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response.  相似文献   
40.
应用免疫细胞化学技术及酶联免疫吸附试验(ELISA)对大鼠腹腔肥大细胞合成和释放肿瘤坏死因子(TNF)的状况进行了观测。结果:新鲜分离纯化的大鼠腹腔肥大细胞胞浆呈TNF蛋白阳性。单纯肥大细胞培养早期(2~4 h),上清液中未能检测到TNF,随着培养时间延长,上清液中TNF含量增多;盐酸吗啡与肥大细胞共同培养2h时,上清液中出现可测TNF。四甲基偶氮唑盐(MTT)比色分析试验表明,肥大细胞培养上清液具体有TNF的抗肿瘤活性中。提示:大鼠腹腔肥大细胞能合成和释放TNF,盐酸吗啡能促进肥大细胞释放TNF。  相似文献   
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