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Newborn mongrel dogs were sensitized with conjugates of ovalbumin (OA) and 2,4-dinitrophenol (OA-DNP3) in the presence of Al(OH)3 to produce high levels of anti-OA and anti-DNP IgE antibody. At 4-6 months of age, when anti-DNP and anti-OA antibody levels reached titers of 64 by passive cutaneous anaphylaxis, the dogs underwent separate inhalation and intravenous challenges with conjugates of DNP and bovine gamma globulin (DNP15-BGG) and OA. Inhalation challenge with DNP15-BGG and OA resulted in 5- and 10-fold increases in airflow resistance, respectively. Intravenous challenge with either DNP15-BGG or OA produced profound anaphylaxis with 60-80% decreases in blood pressure, cardiac output and regional blood flows in the carotid, superior mesenteric and renal arteries, and the distal aorta. Treatment of sensitized dogs with 5 doses of 20 mg of conjugates of DNP and polyvinyl alcohol (DNP2-PVA) on alternate days resulted in suppression of anti-DNP IgE antibody production; abrogation of established airway and vascular anaphylactic sensitivities; no change in regional blood flows, and no effect on sensitivities to challenge with OA.  相似文献   
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Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve.  相似文献   
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PURPOSE: To report a retrospective study into the effects of trials on clinical decision-making regarding abdominal aortic aneurysm (AAA) patients suitable for both conventional open (OR) and endovascular aneurysm repair (EVAR). METHODS: A questionnaire was sent to 1400 Dutch surgeons and trainees. Interviewees had to choose between OR and EVAR for AAA patients with and without comorbidity. Specifically, their preferences before and after the publication of 2 randomized trials (EVAR-1 and DREAM) were polled. RESULTS: Of the 524 (37%) questionnaires returned, 223 (43%) respondents treated AAA patients. Before publication of the trials, 160 (72%) preferred OR for the patient without comorbidity and 169 (76%) preferred EVAR for the patient with comorbidity. In total, 72 (32%) respondents changed their preference after the trials were published; however, there was no overall major shift. Focusing on the different cases revealed that the OR preference was significantly enhanced for the patient without comorbidity (p<0.01), while the EVAR preference was significantly enhanced for the patient with comorbidity (p<0.05). CONCLUSION: The randomized trials have not induced major overall changes in surgical decision-making for AAA patients suitable for both EVAR and OR.  相似文献   
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Taurolidine (TRD) has antimicrobial and anti-inflammatory properties. However, the anti-inflammatory effects of TRD in inflammatory bowel diseases (IBD) have not been investigated. Here, we have analyzed the toxicity of TRD after oral long-term application in mice and examined the impact of oral TRD in a dextran sulfate sodium (DSS) model of experimental colitis. Female C57/BL6 mice received TRD in various concentrations (0.1% to 0.4%) for 60 days. Toxicity was evaluated by use of a disease activity index (DAI) and histological examination of major metabolic organs. Furthermore, the impact of 0.2% TRD on a chronic DSS colitis was examined by daily DAI, histological crypt damage score (CDS), bacterial translocation into mesenteric lymph nodes (MLN), and colonic expression of tumor necrosis factor (TNF) alpha, transforming growth factor (TGF) beta, interleukin (IL)-1beta, IL-6, cytochrome oxidase (COX)-2, and monocyte chemotactic protein (MCP)-1 by real-time polymerase chain reaction (PCR). Oral TRD administration for 60 days was well tolerated by the animals and did not show any toxic effects in terms of DAI and histological changes. TRD treatment of DSS colitis led to increased survival of 100%, compared to 33% in the untreated colitis group (p < or = .005). Clinical amelioration was mirrored by significantly reduced DAI and CDS in the TRD treated colitis. Colonic cytokine expression and bacterial translocation into MLN showed no differences between both groups. We thus report for the first time that oral application of TRD results in amelioration of an experimental IBD model. We hypothesize direct intraluminal antimicrobial effects of TRD as well as anti-inflammatory effects during the acute phase of DSS colitis.  相似文献   
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Tissue microarrays (TMA) consist of up to 1000 cylindrical tissue cores from different donor paraffin blocks relocated into one recipient block, allowing for efficient histopathological studies by fluorescence in situ hybridization, RNA in situ hybridization or immunohistochemistry. On the background of the increasing interest of the TMA technique in cancer research and the suggestion of its application also in studies of non‐neoplastic intracranial disorders, the technique was applied to pathologic white matter in AD brains. Eight cases with AD and concomitant white matter pathology were neuropathologically diagnosed on whole brain coronal slides. The TMA technique was used to grade severity of white matter pathology and to quantify small vessels with traditional staining and immunohistochemical markers. These measurements were compared with the whole brain neuropathological assessment. The technique produced good results with preserved tissue structures as confirmed by the whole brain evaluation. Severity of white matter pathology evaluated on the TMA cores correlated negatively with small vessel quantities, and statistically significant differences in vessel quantities paralleled different grades of white matter pathology. It is concluded that the TMA technique could be further utilized in studies of dementing disorders, and may have its advantages in large, clinically well‐characterized materials (e.g. in quantitative mapping of white matter changes).  相似文献   
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