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排序方式: 共有662条查询结果,搜索用时 15 毫秒
651.
TA Brown L Rajappannair AB Dalton R Bandi JP Myers CH Kefalas 《Clinical gastroenterology and hepatology》2007,5(8):969-971
A 72-year-old man was hospitalized for exacerbation of chronic obstructive pulmonary disease and was treated with oral prednisone and 7 days of moxifloxacin. Five days after completing the antibiotic course, he developed watery diarrhea and diffuse, crampy abdominal pain. On presentation he was afebrile, and abdominal examination revealed diffuse tenderness without peritoneal signs. Stool tested positive for Clostridium difficile toxin A by enzyme-linked immunosorbent assay. Despite starting oral metronidazole, the patient developed a fever of 101.2 degrees F 36 hours after his initial episode of diarrhea, 12 hours after admission. His abdominal pain intensified and became localized to the right and left lower quadrants. Computed tomography scan revealed both a thickened cecal wall and an edematous appendix with ileocecal stranding consistent with appendicitis. Appendectomy was performed, and the appendix was found to be suppurative in appearance and nonperforated. The cecum had mild edema and erythema, whereas the colon and rectum were grossly unaffected. Pathology examination revealed exudative material in the appendiceal lumen and a diffuse transmural inflammatory cell infiltrate. The patient had an uneventful recovery and continued to improve on oral metronidazole. Although Clostridium difficile colitis and appendicitis are each very common independently, C. difficile as an etiology of appendicitis is exceedingly rare. A review of the literature revealed 2 prior cases. We speculate that this association is underdiagnosed, because milder cases might respond to antibiotic therapy alone, and severe cases might involve the entire colon and require total colectomy. In each scenario, the involvement of the appendix might be overlooked. 相似文献
652.
Effect of cell concentration on bone marrow and peripheral blood stem cell cryopreservation 总被引:4,自引:1,他引:4
The effects of cell concentration during cryopreservation on bone marrow (BM) or peripheral blood (PB)-derived hematopoietic progenitor cells have not been described. The much greater numbers of cells harvested for autologous PB stem cell (PBSC) transplantation requires that the cells be frozen at higher cell concentrations, or in much greater volumes, compared with BM. We cryopreserved 108 PBSC collections from 30 patients at an average (+/- SD) cell concentration of 3.7 +/- 1.9 x 10(8) nucleated cells per mL in 127 +/- 45 mL. The proportion of mononuclear cells was 52.9% +/- 27.2%. The products also contained 2.9 +/- 2.1 x 10(9) platelets/mL and an average red cell proportion of 12.9% +/- 7.2%. The nucleated cell recovery after thawing was 75.4% +/- 13.0%. The nucleated cell concentration during freezing was not predictive for the postthaw recoveries of nucleated cells (P = .38), granulocyte-macrophage colony-forming unit (P = .06) or CD34+ cells (P = .54), or for the viability of mononuclear cells (P = .81). The platelet and red cell concentrations similarly were not predictive for these endpoints. Samples (3 BM, 7 PBSC) from 10 patients were simultaneously cryopreserved at two-fold, and from 5 additional patients (PBSC) at 6- to 24-fold differing cell concentrations. A lower recovery of erythroid burst forming unit was found for samples frozen at higher cell concentrations (P = .04), but no significant differences were found in the other endpoints listed above. The average cell concentration during freezing for each patient's PBSC collections (n = 34 patients) did not predict time to achieve a PB count of > 500 granulocytes/microL (P = .51) or platelet transfusion independence (P = .39). Patients achieved these endpoints of engraftment at medians of 12 and 13 days, respectively. The infusion of these products was generally well tolerated. Similarly, the cell concentration at which BM cells were frozen did not predict for the duration of granulocyte (P = .63) or platelet (P = .36) aplasias for 54 patients undergoing autologous BM transplantation. These data suggest that PBSC or BM cells collected for transplantation may be cryopreserved at very high cell concentrations without loss of engraftment potential or undue infusion-related toxicity. 相似文献
653.
Fujihara M; Takahashi TA; Azuma M; Ogiso C; Maekawa TL; Yagita H; Okumura K; Sekiguchi S 《Blood》1996,87(6):2386-2393
Ultraviolet-B (UV-B) irradiation of antigen presenting cells (APCs) modifies their allogenecity, resulting in inhibition of the proliferative response of T cells in mixed lymphocyte reaction (MLR). Costimulation by the CD28 ligand CD80 (B7/B7-1) and CD86 (B70/B7-2) plays an important role during T-cell proliferation by augmenting synthesis of interleukin-2 (IL-2) and other cytokines. In this study, we demonstrated induced expression of both CD80 and CD86 during allogeneic MLR, though human freshly isolated monocytes express CD86 constitutively with a much lower level of CD80. A monoclonal antibody (MoAb) against CD86, but not CD80, efficiently inhibited allogeneic T- cell proliferative responses stimulated with highly purified monocytes. UV-B exposure (0 to 1,000 J/m2) of monocytes inhibited the proliferation of T lymphocytes in MLR in a dose-dependent manner. Flow cytometric analysis showed that UV-B exposure of monocytes impaired the constitutive expression of CD54 (intercellular adhesion molecule-1) by 24 hours after irradiation, but the effect on CD86 was relatively less. The surface expression of CD80, CD86, CD54, and HLA-DR on monocytes was further augmented by interferon (IFN)-gamma; this cytokine-induced expression was dose-dependently reduced by UV-B irradiation. Similarly, the upregulation of these molecules following allogeneic MLR was downregulated by UV-B irradiation. UV-B irradiation of monocytes inhibited the expression of IL-2 mRNA in monocyte-stimulated allogeneic MLR. In contrast, the addition of anti-CD28 MoAb at the onset of MLR prevented, at least partially, the reduction of IL-2 mRNA. These results strongly suggest that the impairment of inducible expression of CD86 and CD80 may contribute to the reduced MLR response following exposure of monocytes of UV-B. 相似文献
654.
Perepechaeva ML Seredina TA Sidorova YA Pivovarova EN Markel AL Lyakhovich VV Grishanova AY 《Biomedical and environmental sciences : BES》2017,30(4)
<正>We studied effects of nutrient quercetin on cytochromes’Р450 1А(CYP1A)activities(measured spectrofluorimetrically using 7-ethoxy-resorufin for CYP1A1 and 7-methoxy-resorufin for CYP1A2 as substrates),on mR NA levels(measured by RT-PCR),and on DNA-binding activities(evaluated by an electrophoretic mobility shift assay)of proteins regulating CYP1A expression in untreated and benzo(α)pyrene(Ba P)-treated rats.Wistar rats 相似文献
655.
目的对中心注射室护理工作的满意度进行调查,了解影响医院护理工作满意度的因素。方法选择2011年1~12月在中心注射室接受治疗的患者252例为研究对象,采用问卷法对患者进行调查,并分析影响注射室护理工作满意度的因素。结果接受调查的住院患者中,患者的满意度得分与患者的年龄、受教育程度、收入水平、住院科室、住院天数以及是否手术存在相关性。结论护理人员应重视和加强护理工作质量和效率,提高临床患者对护理工作的满意程度。 相似文献
656.
Jonathan?M?Street Perdita?E?Barran C?Logan?Mackay Stefan?Weidt Craig?Balmforth Tim?S?Walsh Rod?TA?Chalmers David?J?Webb James?W?DearEmail author 《Journal of translational medicine》2012,10(1):5
Background
Exosomes are released from multiple cell types, contain protein and RNA species, and have been exploited as a novel reservoir for disease biomarker discovery. They can transfer information between cells and may cause pathology, for example, a role for exosomes has been proposed in the pathophysiology of Alzheimer's disease. Although studied in several biofluids, exosomes have not been extensively studied in the cerebrospinal fluid (CSF) from humans. The objective of this study was to determine: 1) whether human CSF contains exosomes and 2) the variability in exosomal protein content across individuals. 相似文献657.
目的:观察胆囊腺瘤和胆囊腺癌细胞中Survivin与p53蛋白定位表达和形态特征,研究其在病理诊断及鉴别诊断中的意义。方法:采用免疫组化方法(SP法)检测25例胆囊腺瘤和53例胆囊腺癌细胞中Sur-vivin与p53蛋白的表达。结果:25例胆囊腺瘤,23例Survivin蛋白细胞浆内表达,阳性率92%;其中21例核上表达,包括"核上核样"表达17例、"核上泥沙样"表达4例;细胞浆弥漫表达2例;p53蛋白在胆囊腺瘤组织中无表达。53例胆囊腺癌,Survivin蛋白细胞浆弥漫表达,阳性率75.47%;p53蛋白细胞核内表达,核内表达率77.36%。Survivin在胆囊腺瘤和胆囊腺癌中的表达阳性率虽无显著性差异,但表达部位和形态特征显著不同。结论:Survivin在胆囊腺瘤中的"核上核样"和"核上泥沙样"表达,特异性强,有望成为胆囊腺瘤的诊断性抗体;其与p53在胆囊腺癌组织中核阳性表达、胆囊腺瘤组织中无表达这个结果相结合,构成两者在分子形态学表达的差异性,可作为胆囊腺瘤和胆囊腺癌病理鉴别诊断中的一种分子学方法,结合HE切片,基本可解决胆囊腺瘤与胆囊腺癌的病理诊断与鉴别诊断问题。 相似文献
658.
目的基于时域有限差分(finite-difference time-domain,FDTD)法研究长骨弹性模量对超声导波传播特性的影响,为早期骨质疲劳的超声导波检测方法提供理论依据。方法对长骨进行理论建模,并对不同弹性模量下的长骨模型进行FDTD仿真;通过对仿真数据的分析,计算出不同模式导波的相速度、群速度、中心频率及能量等特性参数。结果长骨的弹性模量与超声导波的传播特性参数密切相关,各个导波模式的相速度、群速度、中心频率和能量均随弹性模量的减小而减小,其中L(0,5)模式的变化趋势最为显著。结论超声导波的传播特性参量能够反映出长骨弹性模量的变化,进而为长骨早期疲劳诊断提供了一种可能的方法。 相似文献
659.
660.
目的:评价我院口服心脑血管类中成药使用情况,为临床合理用药提供参考。方法:对我院2007~2009年口服心脑血管类中成药的种类、年销售金额、用药频度(DDDs)、日均费用(DDC)等进行统计分析。结果:我院2007~2009年口服心脑血管类中成药呈上升趋势;该类药品以胶囊、片剂及滴丸为首选剂型;排序比值同步性较好。结论:我院口服心脑血管类中成药临床使用基本合理,以新剂型、疗效确切、价格低廉的中成药在临床应用中具有优势,但也存在仍需改进的地方。 相似文献