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991.
目的分析我院恶性肿瘤患者医院获得性感染洋葱伯克霍尔德菌的临床特点及对常用抗菌药物的耐药性,为临床合理治疗提供依据。方法回顾性分析2011年1月至2013年12月,从我院恶性肿瘤感染患者送检的细菌培养标本;细菌鉴定用美国BD公司phoenix-100全自动细菌鉴定药敏系统,药敏试验采用纸片法,同时使用WHONET 5.6软件对相关资料进行统计。结果从检测部位分析主要分布在下呼吸道(74.1%),其次为血液(9.4%);药敏试验表明139株洋葱伯克霍尔德菌对米诺环素、氯霉素、美罗培南、头孢他啶和头孢哌酮/舒巴坦仍较敏感,可作为临床治疗洋葱伯克霍尔德菌感染的首选药物,其余15种抗菌药物的耐药率高达30.0%~100%。结论洋葱伯克霍尔德菌在恶性肿瘤患者中的耐药现象非常严重,临床应引起高度关注,及早进行微生物学检测,并根据药敏试验结果合理选用抗菌药物。 相似文献
992.
杨橹伶 《氨基酸和生物资源》2014,36(3):44-46
为了观察肠内营养(EN)支持治疗联合复方氨基酸在恶性肿瘤化疗患者中的临床疗效及并建立相关护理方法,将68例恶性肿瘤化疗患者随机分为治疗组和对照组,每组34例,治疗组给予肠内营养支持治疗联合复方氨基酸治疗,对照组给予常规处理。对两组病人治疗前后进行生化指标监测、记录不良反应以及进行营养评估。研究结果显示,治疗组与对照组比较,人体测量值增加,血清清蛋白升高,两组比较有显著性差异(p<0.05)。本研究表明,肠内营养(EN)支持治疗联合复方氨基酸对于改善恶性肿瘤化疗病人的营养状况效果明显,并且可以提高患者对化疗的耐受力、增强免疫功能。 相似文献
993.
香菇是全球人工种植最为普遍的食用菌,近年来,国内外的研究者对香菇进行了深入的研究,发现香菇在预防、治疗恶性肿瘤方面都具有重要的药用价值。尤其是香菇多糖制剂现已正式作为辅助化疗药物应用于临床。但是对香菇中蛋白质生物学活性的研究以及从蛋白质水平去发掘其抗肿瘤活性的功能基因却鲜有报道。本文拟就香菇的基因组、转录组及功能基因挖掘和开发现状进行简要论述。 相似文献
994.
995.
MHC Ⅰ类链相关分子(MICA)是自然杀伤细胞和T 细胞上NKG2D 受体的主要活化性配体,在上皮源性肿瘤细胞表面过表达。NKG2D 与MICA 的结合可有效刺激效应细胞对肿瘤细胞的细胞毒作用。然而,临床观察表明,MICA 会在肿瘤的增殖过程中脱落而形成可溶性MICA(sMICA),这被认为是肿瘤细胞逃脱NKG2D 介导的免疫监视的重要原因。综述在肿瘤细胞中MICA 和NKG2D 的表达与功能、sMICA 的形成与肿瘤免疫逃逸的关联以及介导MICA 脱落的机制,由此探讨肿瘤免疫治疗的新靶点和新策略。 相似文献
996.
Interleukin (IL) -33 is a nuclear protein that is released from damaged cells and acts as an alarmin. We investigated the expression of IL-33 in human gingival fibroblasts after stimulation by tumor necrosis factor alpha (TNF-α). Human periodontal tissue samples were collected and fixed in phosphate-buffered 4% formalin in saline and processed to paraffin blocks. TNF-α was immunostained in samples of ten periodontitis patients and ten controls. Human gingival fibroblasts were isolated using an explant culture technique. The influence of TNF-α on IL-33 in gingival fibroblasts was analyzed using enzyme-linked immunosorbent assay (ELISA). The number of TNF-α positive cells was significantly greater in periodontitis samples than in controls. TNF-α was located mainly in macrophage- and fibroblast-like cells, vascular endothelial cells and epithelial cells. Analysis of IL-33 expression in cell culture lysates showed that TNF-α induced IL-33 in cultured gingival fibroblasts. Periodontitis samples are characterized by Th2 cell dominance, which has been linked to anti-inflammatory responses and periodontal repair. TNF-α-induced IL-33 may link inflammation directly to the IL-33-dependent stimulation of Th2 cytokine producing cells and participate in the induction of lymphocytes, which results in protective, anti-inflammatory and reparative responses. 相似文献
997.
Megumi Saito Kazuhiro Okumura Ikuo Miura Shigeharu Wakana Ryo Kominami Yuichi Wakabayashi 《Experimental Animals》2014,63(3):339-348
Genome-wide association studies have revealed that many low-penetrance cancer
susceptibility loci are located throughout the genome; however, a very limited number of
genes have been identified so far. Using a forward genetics approach to map such loci in a
mouse skin cancer model, we previously identified strong genetic loci conferring
resistance to chemically induced skin papillomas on chromosome 4 and 7 with a large number
of [(FVB/N × MSM/Ms) F1 × FVB/N] backcross mice. In this report, we describe a
combination of congenic mapping and allele-specific alteration analysis of the loci on
chromosome 4. We used linkage analysis and a congenic mouse strain,
FVB.MSM-Stmm3 to refine the location of Stmm3 (Skin
tumor modifier of MSM 3) locus within a physical interval of about 34 Mb on distal
chromosome 4. In addition, we used patterns of allele-specific imbalances in tumors from
N2 and N10 congenic mice to narrow down further the region of
Stmm3 locus to a physical distance of about 25 Mb. Furthermore,
immunohistochemical analysis showed papillomas from congenic mice had less proliferative
activity. These results suggest that Stmm3 responsible genes may have an
influence on papilloma formation in the two-stage skin carcinogenesis by regulating
papilloma growth rather than development. 相似文献
998.
Research involving mesenchymal multipotent/stem/progenitor/stromal/marrow cells (MSCs) have translated to clinical trials at an extraordinary pace. By the time of this review, the public clinical trials database (http://clinicaltrials.gov) has 394 clinical trials listed using MSCs for a very wide range of therapeutic applications. Unexpectedly, the explanation for the increase in clinical trials using MSCs does not lie on a well-defined therapeutic mechanism – dramatic results have been demonstrated in a variety of studies involving different animal models of diseases, often describing discrete therapeutic mechanisms exerted by MSCs. This review will focus on recent data suggesting the involvement of hyaluronic acid (HA) in the beneficial effects of MSCs, evaluate the potential of MSC as modulators of HA and the implications of this modulation for disease therapy. 相似文献
999.
1000.
Anja K Wege Marcus Schmidt Elke Ueberham Marvin Ponnath Olaf Ortmann Gero Brockhoff J?rg Lehmann 《MABS-AUSTIN》2014,6(4):968-977
Humanized tumor mice (HTM) were generated by the co-transplantation of human hematopoietic stem cells and human breast cancer cells overexpressing HER2 into neonatal NOD-scid IL2Rγnull (NSG) mice. These mice are characterized by the development of a human immune system in combination with human breast cancer growth. Due to concurrent transplantation into newborn mice, transfer of MHC-mismatched tumor cells resulted in solid coexistence and immune cell activation (CD4+ T cells, natural killer cells, and myeloid cells), but without evidence for rejection. Histological staining of the spleen of HTM revealed co-localization of human antigen-presenting cells together with human T and B cells allowing MHC-dependent interaction, and thereby the generation of T cell-dependent antibody production. Here, we investigated the capability of these mice to generate human tumor-specific antibodies and correlated immunoglobulin titers with tumor outgrowth. We found detectable IgM and also IgG amounts in the serum of HTM, which apparently controlled tumor development when IgG serum concentrations were above 10 µg/ml. Western blot analyses revealed that the tumor-specific antibodies generated in HTM did not recognize HER2/neu antigens, but different, possibly relevant antigens for breast cancer therapy. In conclusion, HTM offer a novel approach to generate complete human monoclonal antibodies that do not require further genetic manipulation (e. g., humanization) for a potential application in humans. In addition, efficacy and safety of the generated antibodies can be tested in the same mouse model under human-like conditions. This might be of particular interest for cancer subtypes with no currently available antibody therapy. 相似文献