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1.
We describe two patients with lesions clinically resembling pseudoxanthoma elasticum and histologically exhibiting focal elastosis. with normal-appearing elastic fibres in the mid- and deep dermis. We consider that these skin lesions represent a previously undescribed entity, whose pathogenesis appears to be related to the ageing process.  相似文献   
2.
沙蟾毒精抑制肝癌HepG2细胞黏附、迁移和侵袭的作用   总被引:1,自引:0,他引:1  
目的研究沙蟾毒精(Arenobufagin)对人肝癌细胞HepG2黏附、迁移和侵袭的抑制作用。方法 MTT法检测沙蟾毒精对HepG2细胞活力和细胞黏附能力的影响,划痕实验观察沙蟾毒精对HepG2细胞运动能力的影响,Transwell小室模型研究沙蟾毒精对HepG2细胞的迁移和侵袭的抑制作用,Western blot检测基质金属蛋白酶MMP 2和MMP 9的表达水平变化。结果与空白组相比,沙蟾毒精可降低HepG2细胞的黏附能力,使Transwell小室膜上的肝癌细胞明显减少,并且呈剂量依赖性。Western blot结果显示沙蟾毒精可以明显抑制基质金属蛋白酶MMP 2和MMP 9的表达。结论沙蟾毒精能抑制人肝癌细胞HepG2的黏附、迁移和侵袭,其机制可能与抑制MMP 2和MMP 9的表达有关。  相似文献   
3.
中药九节茶提取物对应激负荷小鼠免疫功能的改善作用
  总被引:1,自引:0,他引:1  
目的:研究中药九节茶对束缚应激小鼠免疫功能的改善作用.方法:实验将雄性C_(57)BL/6小鼠分为正常对照组,应激对照组,125,500 mg·kg~(-1)九节茶提取物给药组,制备脾脏淋巴细胞悬液,流式细胞术分析T淋巴细胞亚群、NK细胞和NKT细胞比例及数目.结果:与应激对照组相比,中药九节茶可以提高束缚应激小鼠脾脏淋巴细胞总数,改善T淋巴细胞亚群比例,同时增加脾脏NK细胞和NKT细胞比例及数目.结论:中药九节茶可以改善应激负荷小鼠淋巴细胞数目及淋巴细胞亚群比例.  相似文献   
4.
目的探讨束缚应激反应对小鼠晶状体抗氧化能力指数的影响。方法建立小鼠束缚应激模型,采用荧光酶标仪测定晶状体的抗氧化能力指数,用高效液相-电化学检测器(HPLC-ECD)测定小鼠晶状体中谷胱甘肽含量。结果随着应激时间的延长,小鼠晶状体的抗氧化能力指数和谷胱甘肽含量与正常组相比均有不同程度下降。结论束缚应激状态下,晶状体的抗氧化能力指数和谷胱甘肽水平均相应降低,其机制可能与晶状体内的内源性抗氧化能力降低及氧自由基产生过多和蓄积有关。  相似文献   
5.
Objective: Although enterobacteria are implicated in intestinal immune response, there has been no report on how intraluminal pathogens affect lymphocyte recruitment. The aim of this study was to determine how the presence of intestinal flora affects lymphocyte migration to intestine under physiological and lipopolysaccharide (LPS)‐induced inflammatory conditions. Methods: Interaction of T‐cells with ileal microvessels was monitored by using an intravital microscope in mice under germ‐free (GF) and specific pathogen‐free (SPF) conditions. LPS was administered into either the peritoneal cavity or duodenum before lymphocyte injection. Results: Adherence of T‐cells was greater in SPF than in GF mice, indicating that the presence of enterobacteria upregulated migration under physiological conditions. Intraperitoneally administered LPS significantly increased the adherence of T‐cells in both GF and SPF mice accompanied by the expression of adhesion molecules and proinflammatory cytokines. However, intraluminally administered LPS did not enhance the adherence of T‐cells in SPF mice. A significant induction of increase in mRNA expression of IRAK‐M, a negative regulator of TLR4 signaling, and transforming growth factor beta (TGF‐beta), a regulatory cytokine, was observed in SPF mice after luminal LPS treatment. Conclusions: Tolerance to intraluminally administered LPS in the lymphocyte recruitment process was induced by enterobacteria, possibly via the induction of IRAK‐M and TGF‐beta.  相似文献   
6.
7.
Solitary juvenile polyps are generally non‐neoplastic hamartomatous polyps. Inflammation is suggested as the cause of proliferation and progression of these polyps, and adenomatous and carcinomatous changes are rare. We report a rare case of a solitary juvenile polyp with malignant transformation that developed in the sigmoid colon of a 12‐year‐old boy. A 3 cm, pedunculated polyp was endoscopically resected, and histologic evaluation revealed the characteristic features of a juvenile polyp. However, mucous‐filled ectatic glandular spaces were lined by mucin‐secreting columnar epithelial cells with atypical change, and an admixture of adenocarcinoma invading the submucosa was confirmed. The histologic features may suggest the involvement of the adenoma–carcinoma sequence in the development of adenocarcinoma in the present case. Although rare, solitary juvenile polyps should develop adenocarcinoma and thorough histologic evaluation of the resected polyps is warranted to identify the adenomatous tissue.  相似文献   
8.
Abstract— The anti-anginal effect of nitroglycerin and prostacyclin was examined using, as an index, the ischaemic electrocardiogram (ECG) change (ST elevation) induced by intracoronary arterial injection of 9,11-dideoxy-11α,9α-epoxymethano-PGF (U-46619), a stable thromboxane A2 agonist, in anaesthetized rats. The ST elevation induced by U-46619 (5–20 μg kg?1, i.c.a.) was dose-dependent and reproducible. U-46619-induced ST elevation was markedly prevented by the pretreatment of intravenous administration of prostacyclin (0·01 μg kg?1), and to a lesser extent by nitroglycerin (0·3 mg kg?1). Simultaneously, platelet count decreased significantly in the coronary arterial blood which indicated that platelet aggregation was enhanced by U-46619. The decrease of platelet count in coronary arterial blood at the time of ST elevation was significantly suppressed by prostacyclin (0·1 μg kg?1, i.v.), but not by nitroglycerin (0·3 mg kg?1, i.v.). These results suggest that the ST elevation induced by intracoronary arterial injection of U-46619 may be derived from spasm of coronary artery and platelet aggregation in the intracoronary artery in rats.  相似文献   
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10.
Summary: We examined the production of prostaglandin (P0) E2, 6-keto PGF and thromboxane (Tx) B2, the mass of cyclooxygenase (COX) isoenzymes and the activities of phospholipases A2 and C in glomeruli, cortical tubules and medullary tubules of rat kidneys. Medullary tubules produced significantly greater amounts of PGE2, 6-keto PGF1α. and TxB2 than glomeruli or cortical tubules. the most abundant eicosanoid in medullary tubules was 6-keto PGF1α. By contrast, glomeruli and cortical tubules predominantly produced POE2 (glomeruli > cortical tubules). Levels of COX 1 were markedly greater in medullary tubules than in glomeruli or cortical tubules. Glomeruli had significantly greater amounts of COX 1 than cortical tubules. Detectable amounts of COX 2 were not present in the three preparations. the activity of phospholipase (PL) A2 against phosphatidyicholine (PC) was significantly greater in tubules (medullary tubules > cortical tubules) than in glomeruli. By contrast, there was a significant increase in the activity of PLA2 against phosphatidylethanolamine (PE) in glomeruli as compared to tubules (medullary tubules > cortical tubules). the activity of PLC was the Weatest in medullary tubules. Glomeruli had significantly greater activity of PLC than cortical tubules. the order of magnitude for the total activity of the three phospholipases in membranes was medullary tubules> glomeruli> cortical tubules. the total production rate of POE2, 6-keto PGF1α and TxB2 was in parallel with the amount of COX 1 and the total activity of membranous phospholipases A2 and C in the three preparations. In conclusion, there are differences in the production of PGE2, 6.-keto PGF1α and TxB2, the ainount of COX 1 and the activities of phospholipases A2 andC among glomeruli, cortical tubules and medullary tubules of rat kidneys; and the different aspects of COX 1 and phospholipases A2 and C have a key role in the control of eicosanoid production in the three preparations.  相似文献   
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