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991.
992.
993.
Jian-Xian Yu Lin Cui Qi-Yi Zhang Hua Chen Ping Ji Hong-Jun Wei Hai-Yan Ma 《World journal of gastroenterology : WJG》2006,12(29)
AIM: To study CD34, CD105, inducible nitric oxide synthase (iNOS), endogenous nitric oxide synthase (eNOS), and hypoxia-inducible factor 1 (HTF-1) α expression in human colorectal carcinomas.METHODS: The tissue microarrays (TMAs) were made up of 80 cases of colorectal carcinoma and 80 cases of non-neoplasm colorectal mucosa. The expression of CD34, CD105, NOS and HIF-1α was detected by immunohistochemistry (S-P).RESULTS: iNOS and HIF-1α expression in colorectal carcinoma was significantly higher than in non-neoplasm colorectal mucosa (χ2 = 43.166, P < 0.01; χ2 = 10.4278,P < 0.01); eNOS expression in colorectal carcinoma was significantly lower than in non-neoplasm colorectal mucosa (χ2 = 11.354, P < 0.01). The expression of iNOS correlated with differentiation (χ2= 18.141, P < 0.01),invasive depth (χ2= 4.748, P < 0.01), and Micro vessel density (MVD) (t = 2.327, P < 0.05). The expression of HIF-1α was correlated with infiltrating depth (χ2= 4.397,P < 0.05), Duke's staging (χ2= 4.255, P < 0.05), and MVD (t = 2.272, P < 0.05). No correlation was found in eNOS expression.CONCLUSION: Over-expression of iNOS and HIF-1α in colorectal carcinoma is correlated with the biological character MVD. 相似文献
994.
Haley M Cui X Minneci PC Deans KJ Natanson C Eichacker PQ 《The American journal of the medical sciences》2004,328(4):215-219
Based on the results of the phase III PROWESS trial, recombinant human activated protein C (rhAPC) was approved by the Food and Drug Administration (FDA) for use in severely septic patients. Concerns regarding rhAPC's inconsistent effects, incomplete understanding of its mechanism of action, and its safety in particular subgroups were raised during the FDA's evaluation. This study attempts to assess the cost-effectiveness rhAPC by comparing its effects during recent clinical use to its prior phase III trial testing and by considering other potentially less expensive treatments with effects that may overlap those of rhAPC. In patients with similar numbers of injured organs, mortality rates may be higher with rhAPC during clinical use compared with the phase III trial. There may also be an increased risk of hemorrhage and other adverse events that necessitate early discontinuation of treatment. Many of the patients receiving rhAPC during clinical use may have otherwise been excluded from its phase III trial testing. Data from several recent phase III trials as well as a recent meta-analysis suggest that heparin and physiologic dose steroids offer substantially less expensive alternatives to rhAPC. Further phase IV testing will be required to confirm such possibilities. 相似文献
995.
996.
Ryu T Hosaka N Miyake T Cui W Nishida T Takaki T Li M Kawamoto K Ikehara S 《Bone marrow transplantation》2008,41(7):659-666
We attempted to rescue supralethally irradiated (SLI) mice by transplantation of hematopoietic stem cells (HSCs) plus thymus from variously aged donors (fetus, newborn and adult). Although the transplantations of these kinds of HSCs alone showed a very short survival, newborn liver cells (NLCs) (as the source of HSCs) plus newborn thymus (NT) transplantation markedly improved the survival rate. The transplantation attenuated severe damage in the small intestine, which is one of the major causes of death by SLI. In addition, the donor-derived CD4(+) T cells significantly increased with additional NT transplantation. The production of interleukin (IL)-7 and keratinocyte growth factor, which plays a crucial role in protection against radiation injury in the intestine, was the highest in NT. Finally, SLI mice that had received NLC plus IL-7(-/-) NT transplantation plus IL-7 injection showed improved survival, weight recovery and an elevated number of CD4(+) T cells compared with the mice that had received NLC plus IL-7(-/-) NT or plus IL-7 injection alone. These findings suggest that NLCs plus NT transplantation can rescue SLI mice most effectively, and that high production of IL-7 in NT plays a crucial role with induction of CD4(+) T cells. 相似文献
997.
阿泰宁对噁唑酮诱导的大鼠结肠炎模型的治疗作用 总被引:3,自引:0,他引:3
目的:建立嗯唑酮诱导的大鼠结肠炎模型.观察阿泰宁对噁唑酮诱导的大鼠结肠炎的治疗作用及机制.方法:经直肠注入嗯唑酮建立大鼠溃疡性结肠炎模型.将大鼠随机分为:空白对照组(正常组,n=8),模型组(n=10),美沙拉秦组(正常组,n=10),阿泰宁组(n=10),治疗21d后处死动物,肉眼观察结肠病变,分别测体质量、结肠湿质量、脾脏质量和结肠组织病理学变化,ELISA法测定大鼠血清IL-1β、IL-10、TNF-α以及结肠黏液内容物sIgA含量,考马斯亮兰法测定血清总蛋白,溴甲酚绿比色法测定白蛋白以及肠道菌群培养.结果:模型组、阿泰宁组和美沙拉秦组大鼠体质量均比正常组显著降低(均P<0.01).美沙拉秦组和阿泰宁组血清球蛋白含量、结肠湿质量指数较模型组差异显著(29.9±5.7,29.1±5.4vs23.7±9.5:6.0±0.9.6.2±0.4vs7.4±1.6,均P<0.05).模型组大鼠血清IL-1β和TNF-α含量较正常组、美沙拉秦组和阿泰宁组差异显著(44.6±17.2vs8.8±7.9,14.5±4.7,8.6±3.4,均P<0.01;33.5±7.2 vs 22.6±6.7,22.3±9.2,24.4±10.8,均P<0.05).模型组大鼠血清IL-10含量较正常组、阿泰宁组差异显著(101.5±35.8vs280.5±36.1,271.3±33.8,P<0.01).阿泰宁组脾脏指数、sIgA含量比正常组显著升高(3.4±0.8vs2.7±0.3;46.0±20.3vs23.4±18.5,均P<0.05),而美沙拉秦组差异不显著.较模型组双歧杆菌数量,阿泰宁治疗后明显上升,梭杆菌数量明显下降(9.7±0.1vs9.3±0.2:3.7±0.3vs5.8±0.7,均P<0.01).结论:阿泰宁能够有效治疗噁唑酮诱导的大鼠结肠炎. 相似文献
998.
999.
Richard N. Fedorak Barbara Haeberlin Lonnie R. Empey Ningren Cui Harold Nolen III Laurence D. Jewell David R. Friend 《Gastroenterology》1995,108(6):1688-1699
Dexamethasone-β-d-glucuronide, a colon-specific prodrug of dexamethasone, may be useful in the treatment of ulcerative colitis and Crohn's colitis. The aim of this study was to evaluate colonic delivery and efficacy of this prodrug in the rat. Distribution of dexamethasone in luminal contents and tissues of the gastrointestinal tract and in plasma was measured after oral administration of dexamethasone-β-d-glucuronide or free dexamethasone. Efficacy of the prodrug and free drug was tested in an acetic acid-induced rat colitis model. Healing of induced colitis was assessed by measuring net intestinal fluid absorption, colonic surface area of ulceration, histology, and myeloperoxidase activity. Glucocorticosteroid toxicity was evaluated with serum corticosterone and plasma adrenocorticotropic hormone levels. The drug delivery index (a measure of relative targeting efficiency) was 6.7 and 8.6 in the cecal and colonic mucosa, respectively. The prodrug was significantly more potent than free drug in improving net colonic fluid absorption while significantly reducing surface area of ulceration and histological grade in colitic rats. Treatment with free dexamethasone significantly reduced serum corticosterone levels to subnormal levels, and treatment with the prodrug maintained serum corticosterone and plasma adrenocorticotropic hormone levels near control levels. The prodrug dexamethasone-β-d-glucuronide delivers efficacious amounts of dexamethasone to the large intestine from lower doses than free dexamethasone. 相似文献
1000.
Hematopoietic stem cell dose correlates with the speed of immune reconstitution after stem cell transplantation 总被引:5,自引:2,他引:5 下载免费PDF全文
In the current study, we tested whether higher numbers of hematopoietic stem cells correlate with the speed of immune reconstitution in a congenic transplantation model (C57BL/Ka, CD45.1, Thy1.1-->C57BL/6, CD45.2, Thy1.2) using purified hematopoietic stem cells (c-Kit(+)Thy1.1(low)Lin(-/low)Sca-1(+)). There were 3 different doses of stem cells used (400, 1000, and 5000). Phenotypic analyses in peripheral blood and spleen demonstrated that higher numbers of infused stem cells are associated with more rapid regeneration of T cells (CD4(+), CD8(+), naive CD4(+), naive CD8(+)) and B cells at early time points. The numbers of T and B cells eventually became equivalent between different dose groups at late time points. Production of interleukin-2 and inter-feron-gamma per T cell was similar regardless of stem cell dose even when tested at the time when there were significant differences in peripheral T-cell counts. The improved immune recovery was attributed to a more rapid regeneration of donor-type immune cells. Higher numbers of total thymocytes and signal joint T-cell receptor excision circles were observed in the higher dose stem cell recipients, suggesting that accelerated regeneration of T cells was due to enhanced thymopoiesis. 相似文献