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61.
BACKGROUND & AIMS: Nonsteroidal anti-inflammatory drugs (NSAIDs) are strongly associated with gastroduodenal ulceration. How to manage patients with NSAID-associated ulcers is a common clinical dilemma. High-dose famotidine in the healing and maintenance of NSAID-associated gastroduodenal ulceration was therefore evaluated. METHODS: One hundred four patients with rheumatoid or osteoarthritis who had gastroduodenal ulceration received famotidine, 40 mg twice daily. Sixteen patients stopped and 88 continued their NSAID treatment. Ulcer healing was assessed endoscopically at 4 and 12 weeks. Seventy-eight NSAID users with healed ulcers were then randomized to receive 40 mg twice daily famotidine or placebo and underwent endoscopy at 4, 12, and 24 weeks. RESULTS: Cumulative ulcer healing rates at 12 weeks were 89.0% (95% confidence interval [CI], 82.3%-95.7%) for patients who continued NSAID treatment and 100% (95% CI, 82.9%-100.0%) for those who stopped. The subsequent estimated cumulative gastroduodenal ulcer relapse over 6 months for NSAID users who took placebo was 53.5% (95% CI, 36.6%- 70.3%). This was reduced to 26.0% (12.1%-39.9%) in patients taking famotidine (P = 0.011). CONCLUSIONS: High-dose famotidine is effective ulcer healing therapy in patients who stop or continue NSAID treatment and significantly reduced the cumulative incidence of gastroduodenal ulcer recurrence compared with placebo when given as maintenance therapy. (Gastroenterology 1997 Jun;112(6):1817-22)  相似文献   
62.
Plasma interleukin-1 (IL-1) activity is modulated in part through the simultaneous appearance of several inhibitors of IL-1 action, including interleukin-1 receptor antagonist (IL-1ra) and the soluble IL-1 type II receptor (IL-1RII). However, little is known concerning the plasma appearance of these inhibitors in patients following operative trauma or those with sepsis syndrome. In the present report, plasma IL-1beta, IL-1ra, and soluble IL-1RI and IL-1RII concentrations were evaluated in 118 patients with sepsis syndrome or after elective operative trauma. Plasma concentrations of IL-1ra increased significantly following elective operative repair of thoraco-abdominal and abdominal aortic aneurysms, and after bowel resection for inflammatory bowel disease, but did not increase after laparoscopic cholecystectomy. Plasma IL-1ra levels were also elevated in patients with sepsis syndrome. In contrast, soluble IL-1RII levels were only increased in patients after operative repair of thoraco-abdominal aortic aneurysms and in sepsis syndrome, whereas concentrations were unaffected by the other more modest surgical procedures. Plasma IL-1RI concentrations decreased in all postoperative patients in the first 24 hours after surgery. We conclude that both plasma IL-1ra and soluble IL-1RII concentrations often increase in sepsis and following some operative trauma. Less severe operative trauma increases the plasma concentration of only IL- 1ra, whereas both IL-1ra and soluble IL-1RII are increased in patients with sepsis syndrome or following thoraco-abdominal aneurysm repair.  相似文献   
63.
Characterization of a new megakaryocytic cell line: the Dami cell   总被引:18,自引:6,他引:18  
A new human megakaryocytic cell line (Dami) has been established from the blood of a patient with megakaryoblastic leukemia. The Dami cells grow primarily in suspension with a doubling time of 24 to 30 hours. By light and electron microscopy, the Dami cells range in size from 12 to 120 micron in diameter and have lobulated nuclei characteristic of megakaryocytes. At least 89% of the cells react with monoclonal antibodies against platelet glycoproteins (GP) Ib and IIB/IIIa, and glycophorin. The cells do not react with antibodies against lymphoid, monocyte, granulocyte, or macrophage antigens. Thirteen percent of the cells become polyploid, spontaneously achieving greater than 4N DNA ploidy levels. In response to phorbol myristate acetate (PMA), the proportion of cells with ploidy levels greater than 4N increased threefold and could be separated into discrete ploidy groups. PMA also increased the expression of GPIb, the GPIIb/GPIIIa complex,l and von Willebrand factor. Cytogenetic analysis revealed a human male hyperdiploid karyotype with a modal chromosome number of 54 to 64 and several consistent clonal chromosomal abnormalities. These included a partial deletion of chromosome 5 and a translocation involving chromosome 3. In contrast to other megakaryocytic cell lines in which only a small portion of the cells express the megakaryocytic phenotype, nearly all of the Dami cells express platelet glycoproteins. Thus, the Dami cells provide a superior model in which to study human megakaryocyte biochemistry and differentiation.  相似文献   
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糖尿病视网膜病变易感性与相关基因多态性研究进展   总被引:1,自引:0,他引:1  
糖尿病视网膜病变是糖尿病的并发症之一,在糖尿病患者中,有血糖控制不良且病程较长但未发生糖尿病视网膜病变的情况,也有血糖控制良好且病程较短的但发生严重糖尿病视网膜病变的患者。通过大量的流行病学调查发现,糖尿病视网膜病变的发生、发展除了与血糖控制的情况、病程长短等因素有关外,还与每个人的个体差异有关。  相似文献   
68.
目的:探讨过氧化物酶体增殖物激活型受体γ(PPARγ)及其配体(15-脱氧-前列腺素J2,15-d-PGJ2)对细胞滋养细胞表达基质金属蛋白酶-2(MMP-2)和MMP-9的调控作用。方法:采用免疫荧光细胞化学方法检测细胞滋养细胞中PPARγ的表达;利用免疫荧光共聚焦技术观察15-d-PGJ2作用前后细胞滋养细胞MMP-2和MMP-9表达强度的变化;通过荧光定量PCR(Real-timePCR)和Westernblot方法定量检测MMP-2和MMP-9mRNA和蛋白的表达变化。结果:在细胞滋养细胞中有PPARγ蛋白表达,且主要定位在细胞滋养细胞核中;15-d-PGJ2作用后细胞滋养细胞中MMP-2和MMP-9的表达明显下降,与对照组相比差异显著(P<0.01);15-d-PGJ2对MMP-2的作用强于MMP-9。结论:PPARγ及其配体15-d-PGJ2调节滋养细胞浸润作用可能是通过调节MMP-2和MMP-9的表达实现的。  相似文献   
69.
The submolecular basicities of 21 immuno-modulating, thymopoietin-type di-, tri-, and tetrapeptides were studied and characterized in terms of group constants and partial microconstants. All compounds were derivatives of the H-Arg-Lys-Asp-OH tripeptide. Modifications within four covalent bonds of the basic site (esterification, acylation, curtailment or addition at C-terminal end, exchange of amino acids) cause significant changes in the scheme of protonation and in the individual basicity of proton binding sites. Configurational changes of the component amino acids, however, do not cause significantly different basicities in the diastereomers.  相似文献   
70.
Seo SI, Song SY, Kang MR, Kim MS, Oh JE, Kim YR, Lee JY, Yoo NJ, Lee SH. Immunohistochemical analysis of NF‐κB signaling proteins IKKε, p50/p105, p52/p100 and RelA in prostate cancers. APMIS 2009; 117:623–8. Activation of nuclear factor‐kappa B (NF‐κB) signaling is considered an important mechanism in the development of prostate cancers. A recent study revealed that IκB kinase epsilon (IKKε), an activator of NF‐κB, was overexpressed in breast cancers and acted as an oncogene. Expression of NF‐κB members has been reported in prostate cancer tissues, but expression of IKKε has not yet been studied in prostate cancers. In this study, we attempted to explore as to whether expressions of IKKε and NF‐κB members p50/105, p52/p100 and RelA are altered in prostate cancers. We analyzed the expression of IKKε, p50/105, p52/p100 and RelA in 107 prostate adenocarcinoma tissues by immunohistochemistry using a tissue microarray (TMA) method. In the TMA, IKKε is expressed in basal cells, but not in alveolar cells in normal prostate glands. IKKε is expressed in 60.0% of prostate intraepithelial neoplasm (PIN) and 70.1% of the prostate cancers in the cytoplasm. Nuclear immunostainings of NF‐κB members p50/105, p52/p100 and RelA, which are considered activation of NF‐κB signaling, were observed respectively in 28.0%, 18.7% and 37.4% of the cancers. Nuclear staining was detected neither in normal alveolar cells nor in PIN. However, none of the expression of p50/105 nor p52/p100 nor RelA nor IKKε was associated with pathologic characteristics, including size of the cancers, age, Gleason score and stage. The increased cytoplasmic expression of IKKε as well as the increased nuclear expressions of p50/105, p52/p100 and RelA in the prostate cancers compared to normal alveolar cells suggested that overexpression of these proteins may be related to activation of the NF‐κB pathway and might play a role in tumorigenesis of prostate cancers.  相似文献   
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